International One Health Symposium 2025

Oct 13, 2025, 12:00 PM → Oct 15, 2025, 4:00 PM Europe/Berlin

https://www.hotel-berlin.de/en (Hotel Berlin, Berlin)

 

Welcome to the International One Health Symposium 2025

 

Date: October 13th - October 15th, 2025

Venue: Hotel Berlin, Berlin, Lützowplatz 17, 10785 Berlin

 

Participation fees:

€ 95 for undergraduate student, graduate student, PhD student

€ 290 for postdocs, senior scientists, public health workers, etc.

 

Preliminary program:

The preliminary program is online. Please note that there may still be changes.

 

The abstract submission deadline has been extended to June 15th, 2025.

Please submit your contribution on one of the following topics and read the instructions carefully:

• AMR

• Agriculture & Health

• AI in Health Research

• Climate Change & Health

• Conservation & Wildlife Health

• Emerging Pathogens

• Environmental Pollution & Health

• Genomics & Proteomics

• Novel Methods

• One Health in Public Health

• Pandemic Prepardness & Prevention

• Social Sciences & Health

• Vaccines & Immunology

• Vectors

 

Review results

August 20th + September 2nd: All results have been sent out.

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Note: Foreign participants from all countries (except Germany) who submit an abstract by June 15th, 2025 will have the opportunity to apply for one of five travel grants to cover their travel expenses.

We will automatically contact all eligible applicants by e-mail in the week from June 16th to 20th, 2025 and explain the next steps. If you have any questions about the travel grants, please contact: Anett Wagemann, info@onehealthplatform.net

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Conference language: English                                                                 

Please keep an eye on your e-mail for further announcements.

 

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Funded by:

                 

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Mon, October 13

12:00 PM → 1:00 PM Registration & Finger food

1:00 PM → 1:20 PM Welcome Note

Conveners: Stephan Ludwig, Rita Schwarzelühr-Sutter

1:00 PM Welcome Note: One Health Platform

Ladies and Gentlemen,
We are delighted to welcome you to the second International One Health Symposium in Berlin under the overarching topic “Challenges in a rapidly changing environment”.

Following the further development of the German Research Platform for Zoonoses, which was founded in 2009, into the One Health Platform (OHP), we are delighted that the path to establishing an interdisciplinary One Health research community has been a successful one. After almost two years of funding, the OHP has around 1700 members from various disciplines such as veterinary medicine, human medicine, biology, environmental as well as social sciences. The first pilot and inter- and/or transdisciplinary networking projects have now been launched and the enormous number of applications submitted shows us both your wealth of ideas for exciting One Health topics and the urgent need for research in this area.

In particular, networking with the environmental sector is a central concern of OHP in order to be able to address the topic of One Health in its entirety. This applies not only to the outlook for national research cooperation. Strengthening international networking in particular is a major task that OHP will continue to focus on in the coming years. This networking begins not only with the initiation of contacts between established scientists, but above all in the area of young scienstists, the strengthening of which is also one of the major priorities on the OHP's agenda.

This year's conference will showcase the lively discourse between the various One Health disciplines in an exciting program.

We wish you many interesting discussions over the next few days and look forward to an exciting meeting with you all.

On behalf of the Office of the One Health Platform

Prof. Dr. Stephan Ludwig, Prof. Dr. Martin H. Groschup, Prof. Dr. Fabian Leendertz

Speaker: Prof. Stephan Ludwig (One Health Platform Münster)

1:05 PM Welcome Note: Federal Ministries

Dear Ladies and Gentleman,

I am delighted to speak to you today on behalf of the Federal Environment Ministry and the five other federal ministries involved in the One Health research agreement.

Two years ago, the well-regarded German Research Platform for Zoonoses became the One Health Platform, broadening its focus beyond human and animal health to include environmental health. This was the right decision. The Platform involves six federal ministries – Health, Agriculture, Research and Technology, Economic Cooperation, Environment and Defence. I would like to thank the staff of the Zoonoses Platform office and the members of the Scientific Advisory Board, who have been instrumental in facilitating the transition to the new platform. Their experience and expertise lay the groundwork for managing and improving the new platform. Your work on the One Health Platform is invaluable. The Platform’s research agenda shows that you are already putting the principles of the One Health approach into practice.

At a time when we are facing global challenges such as pandemics, pollution, climate change and biodiversity loss, it is essential that we take an integrated view of human, animal and environmental health. And underscore the importance of One Health as an integral part of our political and scientific agenda. One good example of how human and animal health and the environment are closely interconnected is climate change: its far-reaching impacts are already being felt today but will become even more serious in future. Higher temperatures are negatively affecting human and animal health, and diseases once rarely seen at our latitudes are now spreading. And the impacts of climate change on the environment affect humans and animals, too – for example water scarcity – a problem compounded by increased pollution.

As a result of insights like this, the One Health approach has gained in importance in recent years, making its way into policies at national, European and international level. I would like to outline this briefly.

Speakers: Rita Schwarzelühr-Sutter (Federal Ministry for the Environment, Climate Action, Nature Conservation and Nuclear Safety (BMUKN)), Federal Ministry of Research, Technology and Space (BMFTR), Federal Ministry of Health (BMG) , Federal Ministry of Defence (BMVg), Federal Minister of Agriculture, Food and Regional Identity (BMLEH), Federal Ministry for Economic Cooperation and Development (BMZ)

1:20 PM → 1:50 PM Keynote I: Wim van der Poel: One Health Approach to Control Zoonoses in Changing Animal Production Systems

2:00 PM → 3:45 PM Session 1: AMR

Conveners: Roswitha Merle, Birgit Walther

2:00 PM Phenotypic resistant single-cell characteristics under recurring ampicillin antibiotic exposure in Escherichia coli

Non-heritable phenotypic drug resistance toward antibiotics challenges antibiotic therapies, and phenotypic resistance fosters the evolution of heritable resistance. Here, we describe single-cell characteristics of phenotypic resistant E. coli cells and compare those to characteristics of susceptible cells by exposure to different levels of recurrent ampicillin antibiotic. Contrasting expectations, we did not find commonly described growth arrest of cells. We find that under ampicillin exposure, phenotypic resistant cells reduced their growth rate by about 50% compared to growth rates prior to antibiotic exposure. The growth reduction is a delayed alteration to antibiotic exposure, suggesting an induced response and not a predetermined state as frequently described. Phenotypic resistant cells exhibiting constant slowed growth survived best under ampicillin exposure and, contrary to expectations, not only fast-growing cells suffered high mortality triggered by ampicillin but also growth-arrested cells. Our findings support diverse modes of phenotypic resistance, and we revealed resistant cell characteristics that have been associated with enhanced genetically fixed resistance evolution, which supports claims of an underappreciated role of phenotypic resistant cells toward genetic resistance evolution. A better understanding of phenotypic resistance will benefit combatting genetic resistance by developing and engulfing effective anti-phenotypic resistance strategies.

Speaker: Ulrich Steiner (Freie Universität Berlin, Institute of Biology, Berling, Germany)

2:15 PM The accumulation of antimicrobial resistance genes in a wild chimpanzee population over seventeen years.

The selective pressure exerted by the massive use of antibiotics has led to a rise in antimicrobial resistance (AMR), posing a serious global health problem. This issue is particularly concerning in many regions of Sub-Saharan Africa, where easy access to antibiotics without a prescription and frequent self-medication foster the emergence and spread of antibiotic resistance genes (ARGs). This environment is conducive to the selection and transmission of resistant bacteria, which can affect not only human health but also that of animals and surrounding ecosystems. However, understanding the actual impact of human activity on the spread of resistance genes requires overcoming a major challenge: the difficulty of distinguishing natural from acquired resistance. Here, we use a longitudinal approach to test whether the observed increase in AMR among humans and livestock in West Africa was accompanied by a flow of ARGs into wild chimpanzees (Pan troglodytes verus), our closest genetic relatives, in Taï National Park (TNP), Côte d’Ivoire,the largest remaining fragment of primary forest in West Africa. We analyzed 410 fecal samples from three groups (NEast = 9; NNorth = 15; NSouth = 17 years), collected over a 17-year period, using hybridization capture and high-throughput sequencing to screen for more than 2,000 ARGs to assess ARG richness and resistance type diversity. Both the abundance of ARGs and the diversity of antimicrobial resistance classes increased; we detected ARGs conferring resistance to drugs of high clinical importance (fluoroquinolones, peptides, aminoglycosides, beta-lactams, glycopeptides, glycylcyclines, macrolides, rifamycins, streptogramins, tetracyclines) and moderate importance (diaminopyrimidines, sulfonamides, lincosamides, phenicols, phosphonic acids, sulfonamides), providing strong evidence for ARG flow into this isolated population.

Speaker: Mr Coch Tanguy Floyde Tanga (Helmholtz-Zentrum für Infektionsforschung (HIOH))

2:30 PM Environmental characteristics associated with the resistome from wildlife populations of house mice

Antimicrobial resistance poses a significant challenge to global health. However, the factors that maintain antimicrobial resistance genes (ARGs) within wildlife microbiomes, particularly in species inhabiting human-dominated landscapes, remain unclear. In this study, we analysed ARGs in 846 faecal samples collected from house mice (Mus musculus) on farms in Germany between 2016 and 2022 using metagenomic sequencing. We fitted joint species distribution models to determine which characteristics of the mouse, landscape or climate explain the presence of ARGs within the house mouse microbiome. A model incorporating all identified ARGs revealed that environmental variables and livestock accounted for over 25% of ARG variance, whereas climatic and mouse-associated characteristics accounted for less than 4% each. When differences in genomic localisation, mobility potential and drug class between ARGs are included in the model, agricultural land use and exposure to livestock interacted with genomic mobility potential. In particular, pig density was strongly associated with integron-encoded genes conferring resistance to aminoglycosides and trimethoprim. Our data suggest that landscape conditions influence the presence of specific ARGs with mobility potential within the microbiomes of house mice. A better understanding of the factors impacting ARG prevalence in wildlife species is crucial for determining transmission of antimicrobial-resistant microorganisms from animal reservoirs.

Speaker: Víctor Hugo Jarquín-Díaz (Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany)

2:45 PM Occurrence and characteristics of methicillin-resistant Staphylococcus argenteus in food products in Germany

Staphylococcal species are well-known zoonotic opportunistic pathogens leading to clinical symptoms that range from skin and soft tissue infections to severe blood stream infections as well as human food poisoning. In 2015, S. argenteus was defined as a separate species within the S. aureus complex but with a similar pathogenicity in humans, proven by occasional infectious disease and foodborne poisoning outbreaks especially in Asia and Australia.
To identify methicillin-resistant S. argenteus in the German food chain, we analysed ~6000 presumptive methicillin-resistant S. aureus (MRSA) isolates that have been provided to the German NRL-Staph between 2014 and 2024, mostly in frame of the national zoonoses monitoring. In total, we identified and further characterised 12 mecA-positive S. argenteus strains by whole genome sequencing and phenotypic antimicrobial resistance (AMR) testing. Because all identified S. argenteus isolates originated from Asian seafood, a small study on fish and seafood imports to Germany followed in 2024/2025 which resulted in further ten isolates. All isolates showed a highly clonal structure and less AMR than MRSA from seafood, but harbored relevant virulence genes like staphylococcal enterotoxin and immune evasion cluster genes.
In conclusion, AMR and potentially virulent S. argenteus strains are regularly present in fish and seafood from Asian regions, but have not yet been observed in German food products. The strains might represent a threat to human health.

Speaker: Sven Maurischat

3:00 PM Food System Changes in One Health: Options for Reducing Antimicrobial Use

Background: Inappropriate use of antimicrobials has been linked to resistance to antibiotics in both humans and animals. About three quarters of total antimicrobial use (AMU) originates in agriculture, but a comprehensive understanding of options for reducing agricultural AMU is lacking. Here we estimate the effectiveness of mitigation options across the food system at global, regional, and national levels, including improvements in biosecurity, reductions in food loss and waste, and dietary changes towards healthier and more sustainable diets.

Methods: For our analysis, we first estimate agricultural AMU attributable to both livestock production and seafood production from aquaculture. To estimate AMU per product, we used region and commodity-specific AMU application rates and paired them with animal numbers corrected for their weight at treatment. We used a global food-system model with country-level detail to estimate the impacts of changes in food loss and waste, dietary changes to a set of healthy and sustainable diets (flexitarian, pescatarian, vegetarian, and vegan), and improvements in biosecurity measures on food production in 2030. We then paired the changes in food production across the different options and between 2020 and 2030 with the estimates of AMU per product.

Findings: We estimated agricultural AMU to be 102 kt in 2020, increasing by 18% to 120 kt in 2030, driven by population growth and dietary changes in middle-income countries. Improvements in biosecurity reduced AMU by 22% compared to no intervention in 2030, with greatest improvements in regions with high pork production such as Europe. Halving food loss and waste reduced AMU by 7%, with greatest reductions in regions with aquacultural production such as East Asia. Dietary changes to flexitarian or pescatarian diets reduced AMU by 42-44%, whereas adoption of vegetarian or vegan diets led to reductions of 88-99%, with greatest reductions in regions with high intake of animal source foods such as North America. Combining all measures increased the individual mitigation potentials (e.g., to 57% for combinations with flexitarian diets).

Interpretation: Achieving meaningful reductions in agricultural AMU will benefit most from a combination of measures, including improvements in biosecurity, reductions in food loss and waste, and dietary changes towards healthier and more sustainable diets with lower amounts of animal source foods. Dietary changes are not often considered One Health interventions, but their substantial mitigation potential warrants to be taken into account for effectively addressing the rapid emergence of antimicrobial resistant organisms.

Funding: Bundesministerium für Bildung und Forschung; Wellcome Trust

Speaker: Thomas Burke (University of Göttingen)

3:15 PM Landscape fragmentation and rural land-use drive antimicrobial resistance gene diversity in a wild primate

Antimicrobial resistance is a global health concern caused by the overuse of antimicrobials and environmental contamination. Wildlife exposed to disturbed environments can acquire resistant microorganisms, indicating environmental ARG (antimicrobial resistance genes) contamination and serving as ARG reservoirs. Here, we used a landscape-scale approach to test whether metrics of anthropogenic disturbance influence the abundance and diversity of ARG in brown howler monkeys (Alouatta guariba). We collected 377 fecal samples from 20 groups of howler monkeys. We extracted total DNA from pooled samples and performed shotgun metagenomic sequencing. We used the SqueezeMeta pipeline for metagenomic assembly and ARG identification based on the CARD database. We extracted landscape metrics representing habitat loss and fragmentation using ArcGIS. We applied generalized linear models to test the influence of landscape disturbance on ARG metrics. We identified 441 ARGs, mainly associated with aminoglycoside, carbapenem, and cephalosporin resistance. ARG richness increased with higher agricultural cover, habitat fragmentation, and water bodies in the landscape. ARG diversity and evenness were positively associated with pasture cover and water bodies. Landscapes with rural interfaces and higher fragmentation tend to increase the richness and diversity of ARGs in howler monkeys. Water bodies and pasture cover likely act as important environmental pathways for ARG dissemination.

Speaker: Vinícius Klain (Federal University of Rio Grande do Sul)

3:30 PM Anti-SARS-CoV-2 potential of RSK Inhibitors – Combining synergistic effectiveness and resistance prevention

SARS-CoV-2 infections can have severe consequences, especially for elderly and immunosuppressed individuals. Identifying novel antiviral treatment strategies is an important task, especially in preventing the selection of resistant virus variants. Such treatment strategies include host targeting antivirals (HTAs) and direct acting antivirals (DAAs), each with distinct benefits. Here, we show that SARS-CoV-2 is susceptible to inhibition of the 90kDa ribosomal S6 (RSK) kinases. RSK inhibitors (BI-D1870, BRD 7389) were tested as monotherapies and in combination with the DAAs Remdesivir (RDV) and Nirmatrelvir (NTV). Both RSK inhibitors exhibited anti-SARS-CoV-2 properties in a stand-alone treatment, as well as synergistic effects with the DAAs. Serial passage of B.1.617.2 under increasing inhibitor concentrations (BI-D1870, BRD 7389, RDV, NTV) led to the selection of DAA drug-resistant variants, while the virus remained fully susceptible to RSK inhibitors. Moreover, synergistic combination therapy (BRD+NTV) likewise did not select for resistant viruses. Testing DAA resistant viruses against RSK-inhibitor + DAA drug combinations still revealed a synergistic mode of action, whereas the RDV + NTV combination therapy showed antagonistic effects. In summary, we identified RSK kinases as so far unknown SARS-CoV-2 proviral factor and could show that combining HTAs and DAAs can be a promising new antiviral approach to increase the antiviral efficacy and mitigate resistance selection.

Speaker: Dr André Schreiber (University of Muenster)

2:00 PM → 3:45 PM Session 2: Emerging Pathogens I

Conveners: Corinna Pietsch, Sven Poppert

2:00 PM Epidemiology of Autochthonous West Nil Virus Infections in Lower Saxony in 2024

West Nile virus (WNV) is a mosquito-borne arbovirus causing West Nile fever (WNF) or neuroinvasive disease (WNND). WNV infections are notifiable according to the infection protection law. From May through November 30 there is mandatory screening of blood donors (BDs) for WNV in Germany.
In 2024 eight cases (5 BDs, 2 WNV, 1 WNND) of suspected WNV cases were reported to the local Public Health authorities; Thereof three cases were confirmed as autochthonous. Two of the reported WNV cases had been abroad. One BD was not confirmed. Two BDs were confirmed with Usutuvirus whereas two were confirmed with WNV clade II. Both WNV-positive BDs, from two different counties did not recall any symptoms prior to blood donation nor did they report any travel history outside Lower Saxony (LS) for the time period of 21 days prior to blood donation. After confirmation of the first WNV-positive BD in early September the public was informed by press release. Investigation of the WNND case revealed that the person contracted the infection in Lower Saxony. All three autochthonous WNV cases lived in or in the vicinity of counties where WNV-infections had been diagnosed among horses and birds prior or at the time of infection in 2024.
The occurrence of WNV cases in LS indicates that WNV circulates in Culex spp. populations in Lower Saxony. Awareness needs to be raised among the public towards preventive measures e.g. prevention of mosquito bites as well as eliminating breeding sites for mosquitos.

Speaker: Dr Christiane M Klier (Public Health Authority of Lower Saxony)

2:15 PM Viral Interference During Flavivirus Coinfections

Superinfection exclusion describes the phenomenon of closely related viruses being unable to simultaneously coinfect the same cells. Despite being reported across a wide range of virus families, no general mechanism responsible has been identified. To study how closely related viruses interact, it’s often necessary to use tagged or otherwise genetically modified viruses, since classic detection methods like antibodies or RNA/DNA probes are usually not specific enough to differentiate between them. This, however, comes with potential caveats: depending on the virus used, tagging it can lead to reduced replication rates, which could influence viral interactions. Additionally, any genetic modifications to a virus’s genome, even if not influencing its replication rate, could influence its interaction with the host or other viruses.
In this study, we describe an antibody-based staining method capable of differentiating the two closely related mosquito-borne Orthoflaviviruses WNV and USUV without any genetic modifications. We use it to characterize their interference with one another during simultaneous and sequential coinfections, finding evidence for superinfection exclusion occurring between them. We supplement our findings with qRT-PCR showing that reduced viral infection rates translate to reduced genome replication.

Speaker: Nils Tadewaldt (Friedrich-Loeffler-Institut)

2:30 PM Characterization of viral factors responsible for Arenavirus-host barriers in M. natalensis

Lassa virus (LASV) outbreaks cause up to 18,000 annual deaths in West Africa. Transmission mainly occurs through contact with infected rodents, with Mastomys natalensis as the primary reservoir host. Prior studies showed that homologous LASV strains (isolated from M. natalensis) cause persistent infections in Mastomys, while heterologous strains (isolated from other rodent species) are cleared rapidly. To identify viral factors driving these host restrictions, we created LASV chimeras by inserting single protein sequences from a heterologous strain into a homologous backbone.

The growth kinetics of chimeric and wild-type viruses were compared in vitro. Furthermore, one-week old Mastomys were inoculated with the different chimeras and monitored for four weeks. Virus titers in organs, as well as viral RNA levels and antibody presence in blood were analyzed.

All four chimeric viruses showed attenuated growth in vitro on Vero and Mastomys-derived cells. The homologous wild-type control caused strong systemic infections in vivo. The chimera with a heterologous Z protein showed a similar infection phenotype, however, it also caused pathogenicity. In contrast, the chimeras with the heterologous GP, NP, or L protein only led to low virus titers and rapid clearance, like the heterologous wild-type virus.

Our findings indicate that the LASV GP, NP, and L protein play important roles in the observed virus-host barriers, while the Z protein has minimal effect on host restrictions.

Speaker: Dr Chris Hoffmann (Bernhard Nocht Institute for Tropical Medicine, Virology Department, Hamburg, Germany)

2:45 PM A novel astrovirus isolated from a greater white-toothed shrew

Astroviruses are one of the major causative agents of non-bacterial gastroenteritis in children under the age of five. The number of astroviruses detected in different host species is increasing, but virus isolation remains rare, which limits subsequent investigations. In the present study, a novel astrovirus was isolated from a greater white-toothed shrew (Crocidura russula, family Soricidae), tentatively named CrussAstV.
Whole genome sequences of the virus isolate and of a C. russula were determined, and a close phylogenetic relationship to Jingmen shrew astrovirus 1, detected in Shantung white-toothed shrews, was demonstrated. Electron microscopy investigations confirmed the presence of virions with a star shaped morphology. The highest CrussAstV-RNA loads were detected in kidney tissue, which may indicate a potential transmission route via urine. Ongoing environmental and non invasive urine sampling of the C. russula colony, from which the original animal came from, has so far yielded negative results through RT-qPCR testing. Kidney samples from 24% of screened C. russula (n=243) carried CrussAstV-RNA, but none of 39 lesser white toothed shrews or 93 bicolored white-toothed shrews, even when trapped at the site of a positive C. russula.
In a One Health approach, future studies should evaluate the influence of anthropogenic land use and climate change on the range of these reservoir species to further assess the risk of spill over infections to other host species.

Speaker: Viola Haring

3:00 PM In Vitro Reassortment Between Eastern BTV-16 and Western BTV-1 Reveals Unique Genome Constellations

Bluetongue virus (BTV), an arbovirus transmitted by Culicoides biting midges and circulating as multiple serotypes, possesses a genome composed of 10 segments of double-stranded RNA. BTV evolution is strongly driven by genetic reassortment, which occurs during the co-infection of host cells by two or more BTV strains and may result in novel genotypes with unpredictable phenotypic traits. Therefore, the frequent co-circulation of multiple serotypes in the field increases the probability of such events. In this study, we investigated in vitro the reassortment potential between two genetically distant BTV strains: eastern BTV-16 (BTV-16e) and western BTV-1 (BTV-1w). Using co-infection in cell culture followed by plaque purification, we isolated 157 viral plaques. Among these, 111 were Seg-2 monotypic and included in downstream genomic analyses. Of these, 91 retained the complete genome constellation of either BTV-1w or BTV-16e, while 20 were reassortants, each displaying a unique genomic profile. Segment analysis revealed that BTV-1w predominantly contributed Seg-2 and Seg-7, whereas Seg-3 mostly originated from BTV-16e. Notably, 4 out of 20 reassortants harbored Seg-2 and Seg-6 from different parental strains, while the remaining 16 inherited both segments from the same parent. Ongoing studies are focused on evaluating the virulence and antigenic properties of these reassortant viruses to better understand their potential impact in natural settings and in serological diagnosis.

Speaker: Dr Shadia Berjaoui (Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale")

3:15 PM Middle East Respiratory Syndrome Coronavirus, an Emerging Zoonosis: 2022 Surveillance in One-Humped Camels in Nigeria

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a significant zoonotic virus that the World Health Organization (WHO) has classified as a priority pathogen due to its potential to cause epidemics. As of April 2025, an estimated 2,627 lab-confirmed cases of MERS-CoV, with at least 946 deaths across 27 countries, have been reported. Given Nigeria's porous borders and the transboundary movement of animals, the country is at risk for the transmission of zoonotic diseases, including MERS-CoV. From May to October 2022, we conducted a survey of slaughtered camels, collecting blood, nasal swabs, and tissue samples (n = 454 each; females n = 405; males n = 49) at the Kano abattoir in northwestern Nigeria. We analyzed the sera for MERS-CoV-specific antibodies using the EUROIMMUN® Anti-MERS-CoV ELISA kit and virus neutralization test (VNT). Nasal swabs and tissue samples were tested using an RT-qPCR assay, followed by sequencing. High MERS-CoV antibodies were detected by ELISA (74.8%) and VNT (95.5%). The seropositivity rate was higher in female camels (87.9% by ELISA) compared to male camels (12.0%, P > 0.05). MERS-CoV RNA was detected in 5.0% of nasal swabs and 3.7% of tissue samples. Phylogenetic analysis of the spike protein revealed a 99.9% nucleotide identity with Ethiopian strains, clustering within clade C. These findings confirm exposure of dromedary camels in Nigeria to MERS-CoV, highlighting the need for continuous monitoring using a One Health approach and increased awareness in at-risk groups.

Speaker: Bitrus Inuwa (National Veterinary Research Institute, Vom, Nigeria)

3:30 PM Risk Factors Associated with Mpox Infection: A Case-Control Study in Masaka City and District, Uganda, February–April 2025

Background:
In early 2025, Masaka City was identified as the epicenter of a rapidly growing Mpox outbreak in Uganda, reporting 105 and 125 confirmed cases in February and March, respectively. Preliminary evidence suggested that transmission was driven by close interpersonal contact and specific behavioral and environmental exposures. We conducted a case-control study to identify risk factors for Mpox infection to inform targeted public health interventions.
Methods:
A matched case-control study was conducted between February and April 2025, involving 86 laboratory-confirmed Mpox cases and 172 age- and neighborhood-matched community controls without Mpox history or symptoms. Data were collected using structured questionnaires on demographics, clinical history, behavioral risks, comorbidities, sexual practices, and household structure. Environmental assessments were conducted at case residences. Data were analyzed using Epi Info™ Version 7, and logistic regression was used to estimate crude and adjusted odds ratios (cOR, aOR) with 95% confidence intervals.
Results:
Eighty six Mpox cases were identified, with a mean age of 32 years; the majority were males (52%) and aged 25–34 years 39(45%). Common symptoms included rash (100%), fever (84%), and headache (64%). Multivariate analysis identified four independent risk factors: close contact with individuals with a rash (aOR: 2.5; 95% CI: 1.1–5.8), presence of comorbidities such as HIV or diabetes (aOR: 3.7; 95% CI: 1.6–8.2), male sex (aOR: 3.1; 95% CI: 1.5–6.4), and having multiple sexual partners (aOR: 9.5; 95% CI: 4.5–17.8). Environmental assessments revealed crowding and multifunctional households that impeded isolation.
Conclusion:
Mpox transmission in Masaka was associated with behavioral, clinical, and environmental risk factors. Targeted risk communication, behavior change interventions, early detection strategies, and urban planning reforms are essential to reduce Mpox transmission in high-risk urban settings.
Keywords: Mpox, case-control study, Uganda, outbreak, risk factors, urban health

Speaker: Ms Gertrude Abbo (Uganda National Institute of Public Health)

3:45 PM → 4:30 PM Coffee Break

4:30 PM → 5:00 PM Keynote II: Thomas Mettenleiter: One Health Governance – from national initiatives to the global pandemic agreement

Convener: Sascha Knauf

5:00 PM → 6:30 PM Session 3: Pandemic Preparedness & Prevention and Social Sciences & Health

Convener: Maresa Neuerer

5:00 PM SARS-CoV-2 evolution on a dynamic immune landscape

Since the onset of the pandemic many SARS-CoV-2 variants have emerged exhibiting substantial evolution in the virus’ spike protein, the main target of neutralizing antibodies. A plausible hypothesis proposes that the virus evolves to evade antibody-mediated neutralization (vaccine- or infection-induced) to maximize its ability to infect an immunologically experienced population. Because viral infection induces neutralizing antibodies, viral evolution may thus navigate on a dynamic immune landscape that is shaped by local infection history. We developed a comprehensive mechanistic model, incorporating deep mutational scanning data, antibody pharmacokinetics, and regional genomic surveillance data, to predict the variant-specific relative number of susceptible individuals over time. We show that this quantity precisely matched historical variant dynamics, predicted future variant dynamics and explained global differences in variant dynamics. Our work strongly suggests that the pandemic continuously shapes variant-specific population immunity, which determines a variant’s ability to transmit, thus defining variant fitness. The model can be applied to any region by utilizing local genomic surveillance data, allows contextualizing risk assessment of variants and provides information for vaccine design.

Speaker: Sofia Paraskevopoulou (Department MFI, Robert Koch Institute, Berlin, Germany)

5:15 PM Mx-mediated Host Restriction of Emerging Highly Pathogenic Avian Influenza H5N1 Viruses

Since 2022, H5N1 highly pathogenic avian influenza (HPAI) viruses of clade 2.3.4.4b caused unprecedented outbreaks in wild birds and increasing mammal infections, including spill-over into humans. These events raised concerns that H5N1 viruses may further adapt to humans. Indeed, some H5N1 viruses isolated from mammals carry adaptive mutations enhancing receptor binding and polymerase activity. However, efficient human-to-human transmission requires evasion of the human innate immune factor Mx1 (MxA), which restricts replication of zoonotic influenza A viruses (IAVs).
Here, we first investigated (i) if human MxA strongly suppresses H5N1 clade 2.3.4.4b viruses from mammals and (ii) when such H5N1 viruses can escape MxA restriction. Our results show that human MxA strongly suppresses replication of all tested H5N1 viruses in vitro and, to a lesser extent, in MxA-transgenic mice. Using a viral polymerase reconstitution assay, we found that replacing the H5N1 NP with that of a human-adapted H1N1 virus conferred MxA resistance. We further addressed reassortment potential of H5N1 with human-adapted IAVs carrying MxA-resistant NP segments. Using qPCR genotyping, we identified reassortants from co-infections and assessed their replication, polymerase activity and MxA evasion.
Our study reveals molecular barriers limiting transmission of zoonotic H5N1 and highlights genetic constellations possibly enhancing human adaptation, contributing to risk assessment and pandemic preparedness.

Speaker: Dr Jakob Ankerhold (University of Freiburg Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany)

5:30 PM The One Health Teaching Clinic: An Educational Model for Integrating One Health in Schools

Effective and contemporary educational strategies are essential components for integrating the concept of One Health into (formal) education in schools. In this talk, we present the One Health Teaching Clinic (OHTC) as an innovative educational model that connects future science teachers with One Health experts from medicine, veterinary science, and environmental fields to tackle today’s most pressing One Health research and sustainability challenges. Rooted in the One Health approach, the OHTC promotes interdisciplinary collaboration and practical problem solving in science education. During a 13-week course, student teachers co-create lesson plans with subject-matter experts, linking classroom learning to real-world issues such as pandemics, climate change, and biodiversity loss. The students then run One Health classroom interventions in schools. The OHTC program is running at six universities across Europe and has already involved around 200 future teachers and over 1,000 secondary school students from year 5 to 13. Early results show clear gains in science communication, systems thinking, and education for sustainable development. The OHTC offers a scalable blueprint for preparing the next generation of teachers to become effective change agents at the intersection of formal education and One Health.

Speaker: Ulrich Hobusch (University College of Agricultural and Environmental Education, Vienna, Austria)

5:45 PM Negotiating cohabitation in a Nigerian abattoir: One Health perspectives of human-animal-ecosystem interactions examined in the light of the SARS-CoV-2 pandemic

As urbanization reshapes ecosystems, human-animal-environment interactions intensify, increasing zoonotic disease risks. This One Health study investigates a key interface: a Nigerian abattoir during the SARS-CoV-2 pandemic. Combining ethnography with semi-structured interviews, and biological sampling of livestock, dogs, and small mammals, we explored zoonotic transmission pathways. Fieldwork in both rainy and dry seasons (2022) revealed the abattoir as a densely shared space, where seasonal rhythms shape interaction intensity. While no SARS-CoV-2 RNA was detected, antibodies were found in cattle, goats, sheep, dogs, and shrews, with notably higher seroprevalence during the rainy season—suggesting prior cross-species exposure shaped by environmental and behavioural dynamics. Our findings underscore the critical role of abattoirs as multispecies hubs and highlight the value of integrating qualitative and serological data in zoonotic surveillance. Strengthening interdisciplinary strategies in such high-contact settings is essential to mitigating emerging health threats and enhancing resilience across species.

Speaker: Valerie Allendorf (Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany)

6:00 PM Readiness for sampling from the environment for One Health Research: Findings from a Population-based Cohort (MuSPAD) in 2024

Introduction
Environmental sources can harbor zoonotic pathogens, and their sampling – central to the One Health approach – supports research at the human-animal-environment interface. This study aims to assess participants’ readiness to collect environmental samples over a two-year period.
Methods
We analyzed data from a test-focused subcohort (PCR-4-ALL) of the Multilocal and Serial Prevalence Study of Antibodies against (Respiratory) Infectious Diseases in Germany (MuSPAD). Participants’ readiness was assessed via an eResearch system.
Results
Overall, 585/1587 (37%) participants answered the questionnaire on readiness, of whom 445 (80%) were willing to sample their environment and 36 (7%) were uncertain. Readiness to collect water from any water source (e.g. puddles, seawater) was observed in 441 (92%) of the respondents, for any soil sample (e.g. garden, plantation) in 346 (72%), for any arthropods (e.g., fly, tick) in 217 (45%) and for leaf swabs in 307 (65%). Overall, collecting once a month consistently shows the highest proportion of readiness to sample.
Conclusion
Study findings suggest participants are willing to engage in research at the human-animal-environment interface, although arthropod collection may require additional education and support. Since this population is accustomed to regular self-testing, their readiness may be overestimated. Environmental DNA provides insights into local animal and microbial communities, complementing other data sources.

Speaker: Ms Dörthe Meyerdierks (Department of Epidemiology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany. Department of Epidemiology, Helmholtz Centre for Infection Research (HZI), Inhoffenstraße 7, 38124 Braunschweig, Germany; Ph.D. Programme "Epidemiology", Braunschweig-Hannover, Germany.)

6:15 PM Towards a One Health Region: Insights from Stakeholders of an Innovation Alliance in Western Pomerania, Germany

The BMBF-funded T!Raum alliance 'One Health Region Western Pomerania' aims to implement One Health principles in the region through transdisciplinary cooperation and knowledge transfer, and to anchor the One Health concept in all decisions by firms, policymakers, and the civil society. The concept of a ‘One Health Region’ is an innovation developed by the T!Raum alliance.
As a key component of the strategic project RegioTransformOneHealth, a broad stakeholder analysis was conducted, including 32 qualitative interviews with regional stakeholders from various sectors, such as veterinary and human medicine, environment, tourism, hunting, agriculture, and forestry. The interviews focused primarily on the necessity for transformation processes to establish a One Health Region in Western Pomerania.
Stakeholders were mainly positive about the establishment of a One Health Region. Necessary transformation processes include strengthening regional value chains, promoting environmental protection initiatives, recruiting qualified young talent for healthcare services, expanding public transport, and increasing cooperation between business and politics.
Collaboration between stakeholders and the T!Raum alliance has the potential to sustainably improve holistic health outcomes, thereby supporting the development of a One Health Region. A preventive and interdisciplinary approach can help mitigate health crises and foster innovative business models in healthcare and regional development.

Speaker: Susan Thomschke (Chair of Economic and Social Geography, University of Greifswald)

5:10 PM → 6:25 PM Session 4: Climate Change & Health

Conveners: Anja Widdig, Christiane Klier

5:10 PM Modeling the potential distribution of Wesselsbron, Sindbis, and Middelburg viruses and their vectors in Africa under future climatic and land-use changes

Outbreaks of zoonotic arboviruses originating in Africa have emerged amidst complex ecological changes. Despite sporadic epizootics and human cases of Wesselsbron virus (WSLV), Sindbis virus (SINV), and Middelburg virus (MIV) in Africa, knowledge of associated risks remains insufficient for prevention. Using the Maximum entropy approach, we developed species distribution models that predict the ecological drivers and niches of arboviral diseases in Africa. We used the ecological niches of Aedes circumluteolus and Aedes mcintoshi for WSLV; Culex univittatus and Culex pipiens for SINV; and Mansonia africana and Aedes mcintoshi for MIV. Mosquito species occurrence data were combined with climate and land-use data for current (2015) and future (2021 – 2040) scenarios under two shared socioeconomic pathways of emission and climate projections. Our analyses show that changing patterns in precipitation, especially precipitation in dry and warm seasons, urbanization, human population, livestock density, and climate change exacerbate mosquito expansion and risk for arboviral diseases into new geographic areas. The models predicted hotspots for WSLV, SIV, and MIV in Southern and Eastern Africa and future expansions to the Sahara Desert. Our study highlights the role of climate change in shaping arboviral disease transmission and provides spatial maps to aid targeted surveillance and early outbreak detection.

Speaker: Maureen Nabatanzi (Center for Development Research (ZEF), University of Bonn)

5:25 PM Regional and seasonal variations in the impacts of large-scale teleconnections of the European-North Atlantic region on mosquito abundance in Germany

Several parameters have been used in recent modelling studies to predict the distribution and abundance of arthropod vectors of medical importance. These include several climatological, meteorological and anthropogenic parameters which influence the lifecycle, traits, and flight activities of mosquito vectors. However, the impact of large-scale atmospheric teleconnection patterns in the European-North Atlantic (EUNA) region on mosquito populations is yet to be examined. This study therefore evaluates the potential of EUNA teleconnection patterns such as the North Atlantic Oscillation (NAO), Arctic Oscillation (AO), the Summer East Atlantic (SEA) pattern, East Atlantic Western Russia (EAWR) pattern and the Scandinavian (SCAND) pattern on mosquito abundance in Germany. Using a long-term German-wide mosquito surveillance dataset, time-series regression and temporal-mode principal component analysis (T-mode PCA), we investigated regional and seasonal-specific relationships between EUNA teleconnections and mosquito abundance and diversity in Germany. We found that the EAWR and SEA play a major role in the regional and seasonal variations of mosquito abundance in Germany. Using distributed lag nonlinear models (DLNMs), we found that the strength and mode of the main EUNA teleconnections in the hibernation seasons (winter: lag of 90 days) determine mosquito abundance in the emergence and activity seasons of mosquitoes (e.g., spring and summer). Mosquitoes are highly abundant in the warmest, driest and lowland regions of Germany. These findings contribute to the state-of-the-art on the impacts of natural climate variability on mosquito populations and serves as basis to advance and expand monitoring and forecasting tools of mosquito vectors – an important step to combat the recent surge of mosquito-borne diseases (MBDs) in Germany.

Speaker: Mr Emmanuel Adeleke (Chair of Regional Climate Change and Health, University of Augsburg)

5:40 PM Leptospirosis Occurrence in Europe: Understanding Environmental and Socio-Economic Drivers Using Machine Learning

Leptospirosis is a rodent-borne infectious disease posing a growing global health threat. Human infections occur through contact with environments contaminated by host urine. Recent ECDC reports indicate a rising trend in Leptospirosis cases across Europe, highlighting the need for improved public health measures. Understanding the factors driving leptospirosis occurrence can enhance surveillance and preparedness actions. Here, we investigate environmental drivers of leptospirosis in Europe using a predictive modelling framework. We implemented an XGBoost model to predict the occurrence of at least one leptospirosis case based on temperature, rainfall, environmental, and socio-economic factors, including population density and GDP. We developed the model using the ECDC leptospirosis patient data at the NUTS3 and monthly resolution. The dataset contains 3,868 occurrence and non-occurrence records from 2009 to 2021. We also conducted a SHAP analysis to understand the feature importance. We achieved 75.97% accuracy, 74.56% precision, and 82.93% recall for the model in prediction, indicating a balanced performance in detecting leptospirosis case occurrences and absences. The SHAP analysis revealed that temperature, livestock population, employment rate, and population density made the most considerable predictive contributions to a case occurrence. Our results contribute to developing spatial risk mapping and prediction to inform healthcare and prevention planning.

Speaker: Omid Airom (1. Heidelberg Institute of Global Health (HIGH), Heidelberg University Hospital, Heidelberg University, Heidelberg, Germany. 2. Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany.)

5:55 PM “Heat is a danger to my health even though I said I am used to it”: Qualitative insights of heat among Community Health Workers and Promoters in Kenya

Climate change is one of the most prominent environmental and health challenges of the 21st century. Variations in extreme temperature and weather events are intensifying occupational heat exposure and placing workers at increasing risk of heat-related illness (HRIs) and injury. Healthcare workers especially those in resource-limited, community-based, or mobile settings face significant occupational risks from rising temperatures, yet these challenges remain largely overlooked and insufficiently studied. This qualitative study based on semi-structured face-to-face interviews explores the experiences of Community Health Workers (CHWs) and Community Health Promoters (CHPs) in Kenya, examining how extreme heat affects their personal health, livelihoods, and the delivery of community-based health services. We conducted 41 in-depth interviews with CHWs and CHPs in Mombasa and Tana River counties. Data was managed using NVivo 14 and analysed drawing on tenets of reflexive thematic analysis. We identified a pattern of intersecting vulnerabilities shaped by economic inequality, work conditions, health disparities, climate variability, and gender. We also found that these overlapping factors not only shape the daily experiences of CHWs and CHPs but also constrains their resilience and effectiveness of community health service delivery. Our findings highlight the urgent need for climate-resilient health systems that not only improve the working conditions or protect CHWs and CHPs from extreme heat but also address the structural inequalities such as economic disparities and the challenges of gendered burdens that heighten their vulnerability. By incorporating intersectional approaches to policy and intervention design, our research calls for a more inclusive, equitable response to climate change within the health sector, ensuring that CHWs and CHPs are supported, valued, and equipped to continue their essential work in the face of a changing climate.

Speaker: Ms Teresia Wamuyu Maina (Heidelberg Institute of Global Health)

6:10 PM Water Reuse from the One and Planetary Health Perspective

Rising temperatures, changing precipitation patterns and increasing frequencies of drought periods have impacted the water availability in Germany. Especially agriculture is facing challenges due to an increasing demand for irrigation water. The use of reclaimed water, i.e. wastewater that has been treated to be suitable for another use, can help to alleviate the pressure on freshwater resources. However, water reuse comes with risks and potential trade-offs. Remaining pollutants, including contaminants of emerging concern (e.g. pharmaceutical residues, PFAS) as well as human pathogens can enter the food chain, can accumulate in soils, plants or reach groundwater and drinking water resources. Additional water treatment processes can be energy-intensive, contributing to an increase in CO2 emissions. Using the reclaimed water, instead of discharging it to the river, can have adverse impacts on the ecological flow. Water reuse thus requires to be assessed from a “One and Planetary Health” perspective to ensure an appropriate balance between healthy ecosystems, human and animal health, nutrition, socio-economic development as well as climate change mitigation and adaption. This has guided the interdisciplinary discussions on national requirements for water reuse complementing the EU regulation 2020/741 on minimum requirements for water reuse. The negotiations between the different objectives were partially hampered by the lack of a common tolerable risk level.

Speaker: Manuela Helmecke (German Environment Agency (UBA), Dessau, Section II 2.1 General Aspects Water and Soil)

6:30 PM → 8:00 PM Snacks & Poster Viewing I

Tue, October 14

8:30 AM → 9:00 AM Registration

9:00 AM → 9:30 AM Keynote III: Amy Pruden: Informing and prioritizing AMR mitigation strategies through 'omics-based environmental surveillance

Convener: Szilvia Neuhaus

9:30 AM → 11:00 AM Session 5: Environmental Pollution & Agriculture & Health

Conveners: Szilvia Neuhaus, Arne Hegemann

9:30 AM A rapid response mobile laboratory for (waste)water monitoring in emergency settings

Water monitoring represents a critical nexus in One Health frameworks, serving as the intersection where human, animal, and environmental health systems converge. Natural disasters frequently compromise water distribution networks and disrupt the laboratory infrastructure essential for water quality assessment. Here we present a portable laboratory utilizing commercially available testing platforms to deliver point-of-care water analysis capabilities. The system was deployed with the World Health Organization to a remote island near Madagascar, addressing critical water quality monitoring gaps following a post-cyclone emergency declaration.
The mobile laboratory incorporates a handheld device for comprehensive water analytics. The testing suite includes contamination indicator assays for alkalinity, free and total chlorine, phosphate, nitrate/nitrite, and ammonia, alongside rapid detection methods for manganese and arsenic. Microbiological assessment of E. coli and coliform bacteria is conducted through count plates and presence/absence tests. All analytical parameters operate within WHO standards. A rapid water concentration protocol enables efficient processing of surface water samples without requiring heavy laboratory equipment. The system features a mobile PCR component for detection of gastroenteric viruses and bacteria.
The demonstrable outcomes of this mobile laboratory deployment encompass enhanced emergency preparedness, inter-organizational collaboration, and operational adaptability. This integrated approach supports the maintenance of continuous water system surveillance, which is fundamental for preventing disease outbreaks, ensuring food security, and protecting vulnerable populations.

Speaker: Dr Arianna Ceruti (Institute of Animal Hygiene and Veterinary Public Health, Leipzig University)

9:45 AM The pESI plasmid may be a burden for Salmonella enterica serovar Infantis in plant environments

Plants serve very often as ecological niche for Salmonella enerica. Fresh plant foods consumed raw have been linked to numerous outbreaks. In recent years, one critical concern has been the multidrug resistance (MDR) observed in Salmonella strains. Among the many serovars, Salmonella serovar Infantis ranks as the fourth most commonly reported serovar in human infections. A megaplasmid named pESI (Plasmid of Emerging Salmonella Infantis) enhances Salmonella colonization in mammalian hosts and improves environmental fitness. It does so by carrying genes that confer resistance to various antibiotics. This megaplasmid is thought to contribute significantly to the successful spread of emerging S. Infantis strains. In our study, we used cress as a plant model for investigating Salmonella persistence. Two S. Infantis strains were included: one carrying the pESI megaplasmid and the other without it. Our results showed that the Infantis strain without pESI persisted better on cress. To explore this further, we obtained transconjugants by mating the two strains. These transconjugants were introduced separately onto cress. The findings confirmed that the strain without pESI exhibited better persistence, and the presence of pESI negatively impacted the strain’s ability to persist in the plant environment. The study revealed that, while pESI offers clear advantages for colonization in mammalian hosts, it acts as a burden for S. Infantis persistence in plant environments.

Speaker: Adam Schikora (Julius Kühn Institute (JKI))

10:00 AM The German Environmental Survey – 40 years of research on exposure to harmful pollutants in humans and their environment

The German Environmental Survey (GerES) is the largest study of human exposure to potentially harmful pollutants in Germany. Since the first cycle started in 1985, it has provided population-representative human biomonitoring (HBM) and ambient monitoring data for 40 years. The sixth cycle has just been completed, and recent samples of urine, blood, tap water, indoor and outdoor air, and house dust, alongside comprehensive questionnaire data (covering i.a. health status, living environment, dietary preferences, personal care product use, biocide application, environmental justice, climate change adaptation and sociodemographic information, among others), will again provide valuable insights into the environmental exposure of the German population. The combination of state-of-the-art analytical HBM methods, questionnaires and ambient monitoring allows for the identification of exposure sources and can also aid in quantifying exposure routes. This presentation introduces GerES as a prototype for a 'One and Planetary Health' survey that integrates human exposure and environmental pollution from various sources to facilitate effective policy advice on exposure reduction measures.

Speaker: Philipp Zimmermann (German Environment Agency, Berlin, Germany)

10:15 AM How soil health-promoting Streptomyces adapt to soil stresses

Actinobacteria of the genus Streptomyces play a crucial role in supporting a fertile and biologically active soil ecosystem due to their unique biological and ecological functions1. They secrete a broad array of hydrolases which break down complex organic compounds like cellulose and chitin needed for recycling of nutrients and enrichment of the soil. They also produce many different antibiotics that suppress soil-borne pathogens, promoting a healthier microbial balance. However, in their natural habitat soil, streptomycetes and other microorganisms are often exposed to rapid changes in their environment such as variations in osmolality due to rainfall or drought. How they adapt to different types of stresses they face in soil is not well understood.

Many strategies that bacteria evolved for the adaptation to stress involve complex second messenger signalling cascades2. Nucleotide-based second messengers are small, diffusible molecules which can be monomeric, such as 3´,5´-cyclic adenosine monophosphate (cAMP) or dimeric for example bis-(3´-5´)-cyclic dimeric adenosine monophosphate (c-di-AMP). Streptomyces use five different nucleotide-based second messengers for signal transduction with dedicated and to some extent overlapping functions3. c-di-AMP is produced out of two molecules of ATP by the deadenylate cyclase DisA and is hydrolysed to the linear pApA and further to AMP by the phosphodiesterase AtaC. Increased levels of the signalling molecule interfere with the formation of stress-resistant spores, while deletion of the deadenylate cyclase makes Streptomyces highly susceptible to osmotic stress4. The molecular mechanisms causing failures in cell functioning upon modulation of c-di-AMP are not yet fully understood. In our recent studies, we found that c-di-AMP affects a range of physiological functions at the cell-environment interface, such as transport and cell wall architecture, and thus fulfils a crucial role for stress adaptation in streptomycetes.

[1] Chater K.F., Biro S., Lee K.J., Palmer T., Schrempf H. The complex extracellular biology of Streptomyce. FEMS Microbiology Reviews, Volume 34, Issue 2, March 2010, Pages 171–198

[2] Bhowmick, S., Shenouda, M.L., and Tschowri, N. (2023). Osmotic stress responses and the biology of the second messenger c-di-AMP in Streptomyces. Microlife 4, uqad020

[3] Latoscha, A., Wörmann, M.E., and Tschowri, N. (2019). Nucleotide second messengers in Streptomyces. Microbiology 165, 1153-1165.

[4] Latoscha, A., Drexler, D.J., Al-Bassam, M.M., Bandera, A.M., Kaever, V., Findlay, K.C., Witte, G., and Tschowri, N. (2020). c-di-AMP hydrolysis by the phosphodiesterase AtaC promotes differentiation of multicellular bacteria. Proc Natl Acad Sci U S A 117, 7392-7400.

Speaker: Natalia Tschowri (Gottfried Wilhelm Leibniz Universität)

10:30 AM Environmental Burden of Disease of IQ loss attributable to lead exposure in Germany

Background: Lead is a pervasive environmental pollutant with no evidence for safe exposure levels in humans. Children represent a particularly vulnerable population due to higher absorption rates and their developing nervous system. Neurodevelopmental effects in children are the most sensitive health outcomes associated with lead exposure. This demonstrates the intricate connection between environmental and human health.
Methods: Environmental Burden of Disease (EBD) assessments enable the quantification of population health impacts attributable to environmental risk factors. We applied a probabilistic Monte Carlo simulation approach to EBD in order to comprehensively account for uncertainty across multiple input parameters. We used nationally representative human biomonitoring data from children and adolescents (3-17 years) in Germany to quantify neurodevelopmental effects from lead exposure.
Results: Our preliminary findings indicate ≈ 20.4 million IQ points lost (95% uncertainty interval [UI]: 12-28 million) attributable to lead exposure in German children. We estimated ≈ 85,000 (95% UI: 0 - 187,000) cases of mild intellectual disability (IQ <70) attributable to lead exposure. Further analyses to quantify Years Lived with Disability (YLDs) are currently ongoing.
Conclusion: Lead exposure in Germany remains a relevant public health concern. Our findings highlight the need for continued efforts to further reduce environmental lead concentrations and lead exposure of children.

Speaker: Paulina Sell (German Environment Agency, Exposure Assessment and Environmental Health Indicators, Berlin, Germany)

10:45 AM A holistic model to assess risk factors of fasciolosis in Ankole cattle

Contemporarily, remote sensing (RS) technology and geographical information systems (GIS) are increasingly used as tools for epidemiological studies and the control of zoonotic diseases. Fasciolosis, a zoonotic disease caused by a trematode parasite (Fasciola spp.), is a good candidate for the application of RS and GIS in epidemiology, strongly influenced by the habitat of the intermediate host. We examined variables which can increase the risk of fasciolosis in Ankole cattle, grazed in the degraded rangelands of north-eastern Rwanda. Risk variables considered included three environmental factors (normalized difference vegetation index, NDVI; normalized difference moisture index, NDMI; normalized difference water index, NDWI), two landscape metric variables (rangeland home-garden ratio, building density), two geological variables (percentage of poorly drained soil, elevation) and three husbandry variables (herd size, adult proportion, body condition score). Fasciola prevalence was used as the dependent variable, sampling season as a fixed factor and four principal components (condensed from the ten risk variables) as covariates in a univariate General Linear Model. Fasciola prevalence was positively correlated to rangeland proportion, cattle herd size, adult proportion and individual body condition. Moreover, high Fasciola prevalence was found in densely vegetated areas with high moisture (high NDVI and NDMI), in combination with large proportions of poorly drained soil at low elevations. Our study underlines the importance of ‘One Health’ and recommends a transdisciplinary approach for effective fasciolosis control integrating sustainable land management, enhanced livestock practices, and aims at public health interventions to mitigate the diseases’ impact on animals, humans, and the environment.

Speaker: Ping Sun (Leuphana University Lüneburg)

9:40 AM → 11:10 AM Session 6: Emerging Pathogens II

Conveners: Stephan Ludwig, André Schreiber

9:40 AM Comparative virology: Risk Group-4 viruses elicit divergent immune responses in the human endothelium

Andes virus (ANDV), Ebola virus (EBOV), and Nipah virus (NiV) are Risk Group-4 viruses that cause fatal zoonotic spillover in South America, Africa, and Asia, respectively. All three viruses cause severe vascular diseases, although they belong to distinct virus families. A major question in comparative virology is if different viruses have similar effects on the same cell-types they collectively target.
To address this, we innovated new approaches to generate nearly pure populations of artery or vein endothelial cells (ECs) from human pluripotent stem cells (hPSCs), a model that offers multiple advantages: they are genetically normal and more physiologically relevant than cancer cell lines prevalently used in research. Infecting hPSC-derived artery and vein ECs with ANDV, EBOV, and NiV revealed that these viruses elicit starkly different host effects. ANDV strongly induced interferon secretion, whereas EBOV and NiV did not. Therefore, while Risk Group-4 viruses are often assumed to block interferon production, ANDV remains an exception. Curiously, while EBOV did not induce interferon production, it strongly upregulated inflammatory cytokine IL-6. Therefore, EBOV appears to induce “immunological misfiring”, activating IL-6 while blocking interferon, thus decoupling these two arms of innate immunity.
This reveals starkly different effects of Risk Group-4 viruses on the human endothelium and highlight the utility of hPSC-derived vascular models to study high-risk pathogens.

Speaker: Dr Isabel von Creytz (Center for Biological Threats and Special Pathogens, Robert Koch Institute, 13343 Berlin, Germany)

9:55 AM A novel trans-Golgi-associated egress pathway of ORF3-deficient hepatitis E virus preserves quasi-envelopment in human hepatoma cells

Hepatitis E virus (HEV) normally exits host cells as quasi-enveloped particles by exploiting multivesicular bodies (MVBs), a process mediated by the accessory protein pORF3. To investigate the functional relevance of this pathway, an ORF3-deficient genotype 3c mutant (HEVΔORF3) was generated and analyzed in two human cell lines: hepatoma-derived PLC/PRF/5 and lung carcinoma-derived A549/D3 cells. While HEVΔORF3 reached wild-type levels of extracellular RNA in PLC/PRF/5 cells, it showed markedly impaired replication in A549/D3 cells, highlighting a strong cell-type dependency in the ability to compensate for the loss of pORF3. Despite reduced infectivity, virions from PLC/PRF/5 cells retained a quasi-envelope, as shown by gradient centrifugation, electron microscopy, and neutralization assays requiring detergent treatment. Confocal imaging revealed altered intracellular trafficking in HEVΔORF3-infected PLC/PRF/5 cells: pORF2 localization shifted from the MVB marker CD63 to the trans-Golgi marker TGN46. This switch was also reflected in virion composition, with TGN46 enriched in HEVΔORF3 particles. These findings identify an alternative, Golgi-associated egress route in hepatoma cells PLC/PRF/5 that preserves quasi-envelopment in the absence of pORF3. Given HEV's zoonotic potential and its ability to cross species barriers, identifying alternative release mechanisms is crucial for assessing host adaptation and transmission dynamics in the One Health context.

Speaker: Dr Nele Gremmel (University of Veterinary Medicine Hannover, Institute of Virology)

10:10 AM Risk assessment of Oropouche virus transmission by mosquitoes in Europe

Oropouche virus (OROV) has emerged as a significant health threat in Central and South America in 2024. Belonging to the genus Orthobunyavirus (family Peribunyaviridae), it is primarily transmitted by Culicoides midges; however, the role of mosquitoes in its transmission cycle has not been fully clarified. This study assesses the vector competence of five mosquito species (Culex torrentium, Cx. pipiens biotype pipiens, Aedes aegypti, Ae. japonicus, and Ae. albopictus) for OROV strain TR 9760 (isolated in 1955 from a febrile patient).
Performing infection via artificial bloodmeal and forced salivation assay under different temperature regimes and timepoints, no infection was detected in Ae. aegypti and Ae. japonicus, independent of timepoint or temperature regime tested. Interestingly, Cx. pipiens biotype pipiens and Cx. torrentium exhibited low-level susceptibility to OROV infection, but no virus was detected in their saliva, indicating they are unlikely to transmit OROV. In contrast, Ae. albopictus exhibited positive saliva, suggesting potential vector competence. Temperature-based risk analysis indicates that regions with established Ae. albopictus populations, may be at risk for OROV transmission.
These findings underscore the importance of virus surveillance and vector control in susceptible areas.

Speaker: Stephanie Jansen (BNITM/UHH)

10:25 AM Alphamesonivirus-1 in Culex pipiens: Genomic Insights and Diagnostic Tool Design

Mesoniviruses (Order: Nidovirales) are generally considered insect-specific viruses that do not infect vertebrates. However, this assumption was recently challenged by the detection of Alphamesonivirus-1 (AMV1) in two horses that died of acute respiratory syndrome in Italy (Jurisic et al.; J. Virol. 2025). Genetic analysis revealed a close relationship between the viral sequences isolated from the horses and those identified in local Culex mosquitoes, suggesting active local transmission. As part of metagenomic surveillance aimed at characterizing the virome of arthropod vectors, AMV1 RNA was detected in pools of Culex pipiens. These positive samples and the corresponding sequences were used to develop and validate a novel real-time RT-PCR assay for AMV1 detection, which was then compared to an existing pan-Mesonivirus qRT-PCR assay (Diagne et al.; Virus Res. 2020). The new assay was applied to hundreds of Culex mosquito pools collected across Italy to assess viral circulation. Additionally, AMV1 genomic variability was investigated. Three amino acid substitutions—located in ORF1a/ORF1b (RdRp), and ORF2a (Spike)—were uniquely identified in the horse-derived AMV1 sequence, potentially explaining the observed host switch. These findings underscore the importance of metagenomic surveillance in syndromic animals and highlight the need to monitor AMV1 circulation and evolution in Culex mosquito populations.

Speaker: Alessandra Spina (University of Teramo (UniTe), Teramo, Italy - Experimental Zooprophylactic Institute of Abruzzo and Molise (IZSAM), Teramo, Italy)

10:40 AM Multiplex serology to determine the role of wild boar as a reservoir host for hepatitis E virus and a sentinel host for West Nile virus and tick-borne encephalitis virus

Active wildlife surveillance, as part of a One Health approach, enables an early detection of emerging infections to allow the prevention of wildlife-human spillover events. The Eurasian wild boar (Sus scrofa) is a key wildlife species, which is widely distributed in Europe and easily adapts to different habitats. Wild boar and domestic pigs are the main reservoir for hepatitis E virus (HEV) genotype 3, which can be transmitted to humans mainly through consumption of undercooked meat. Wild boar can also serve as effective sentinels for emerging zoonotic pathogens like West Nile virus (WNV), a mosquito-borne orthoflavivirus, and the related tick-borne encephalitis virus (TBEV).
To establish an efficient multi-pathogen serological screening system for wild boar surveillance, we developed a multiplex Luminex magnetic bead-based assay for the detection of antibodies against HEV, WNV and TBEV. Screening of 960 wild boar sera collected in 2023 from eight districts in Saxony revealed high exposure levels to HEV and TBEV in wild boar, whereas WNV was detected at considerably lower levels. HEV RNA was found in five individuals, with phylogenetic analysis indicating a close relationship to subtype HEV-3i.
These findings provide evidence for the circulation of HEV, WNV and TBEV in Saxony, highlighting the value of multiplex serological screening in wild boar as an effective tool for wildlife-based surveillance of these viruses.

Speaker: Lydia Kasper (Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Novel and Emerging Infectious Diseases, Greifswald-Insel Riems, Germany)

10:55 AM Isolation of Chandipura virus from sandflies and detection of neutralizing antibodies in humans, Kenya

Chandipura virus (CHPV) is a sandfly-borne vesiculovirus, family Rhabdoviridae, causing outbreaks of febrile illness and severe neuroinvasive disease. Children can develop an acute encephalitis syndrome (AES) with a case fatality rate of 55-78%. Several outbreaks of CHPV have been reported in India. In 2024, India experienced a large outbreak with 245 cases of AES including 82 deaths. No human infections have been reported outside India, but CHPV has been found in a hedgehog from Nigeria and in sandflies from Senegal and recently from Kenya.
We isolated CHPV from sandflies collected in Kenya in 2019. The complete genomes of the two isolates showed 93-99% pairwise nucleotide identities to strains from Kenya, and 76-80% to those from India and West Africa. Comparative in-vitro phenotypic analyses of Kenyan, Indian, and Nigerian CHPV isolates in sandfly-, mosquito-, and human-derived cell lines, as well as in neuronal cells showed no impairment in genome replication rates and infectious virion production of the Kenyan isolate. Infection of mice with the Kenyan CHPV isolate resulted in rapid onset of neurologic disease and death with significantly higher viral loads in the brain than in other organs. CHPV neutralizing antibodies were detected in 19.4% (196/1.013) human sera collected from three counties in Kenya.
Our data provide evidence that CHPV is widespread in Kenya and infects humans. Testing for CHPV should be considered in patients with neuroinvasive disease in Kenya.

Speaker: Dr Inga Slothouwer (Institute of Virologie Charité Berlin)

11:15 AM → 12:15 PM Poster Slam Viewing

11:15 AM → 12:30 PM Sideprogram: One Health Career get-together

Convener: Sascha Knauf

12:30 PM → 1:45 PM Lunch

1:45 PM → 3:15 PM Session 7: One Health in Public Health I

Conveners: Corinna Pietsch, Michaela Projahn

1:45 PM Geographic dispersal of West Nile and Usutu virus in Berlin, 2023-24

West Nile virus (WNV) and Usutu virus (USUV) are closely related arboviruses that circulate between birds and Culex mosquitoes. WNV infection can cause severe neurological disease while USUV is considered non-pathogenic in humans. This study examined the geographic dispersal and infection rates in mosquitoes of both viruses across Berlin.
Mosquitoes were collected across Berlin covering 50 sites in 2023 and 75 in 2024, and tested for WNV and USUV infection by RT-PCR. In total, 27,793 and 78,434 mosquitoes were collected in 2023 and 2024, respectively. For 2024, two-thirds of the samples have been analysed so far.
We observed a strong increase of virus-positive sites and dispersal of both viruses across the city. WNVsite-specific detection rates increased from 32% to 69% and for USUV from 42% to 87%. With respect to infection rates, a slight decrease was observed for WNV while those of USUV massively increased. WNV was detected in 105 mosquito pools (3.1 %, minimum infection rate (MIR) = 3.78) in 2023 and in 147 pools (2.6%, MIR = 2.94) in 2024. USUV was found in 84 mosquito pools (2.5%, MIR = 3.0) in 2023 and in 247 pools (43.7%, MIR = 4.94) in 2024. Genome sequencing of detected strains is ongoing to investigate if viruses emerged from local amplification or were introduced, and to analyze their phylogeographic spread.
Our study provides evidence for the extensive circulation and ongoing distribution of WNV and USUV in Berlin. Public awareness campaigns should be considered.

Speaker: Dr Corinna Patzina-Mehling (Charité - Universitätsmedizin Berlin)

2:00 PM More than the Sum of Its Parts: Combining Genomic and Epidemiological Data for Comprehensive and Sustainable Pathogen Surveillance

Interconnecting multiple fields and methods has become a crucial part of surveillance systems throughout the recent decade. In this work, we developed a system to integrate data from Germany's mandatory notifications for infections with genomic data in a continuous manner. This constant flow of integrated data enables new insights into the dynamics of and serves as a benchmark for detecting logistical, technological, and scientific challenges of Germany’s surveillance system.
One crucial aspect represents the automation of processes by setting up new digital solutions and standards. The data integration requires a primary ID for sample identification, as well as a secure ID used exclusively for linking case and genomic data. A generic set of properties describes the biological sample and its journey to genomic sequencing. This metadata is utilized, among others, to assess turnaround time and identify potential improvements to expedite the process from sampling to the initialization of public health measures.
In conclusion, the digital developments and infrastructure in this work facilitate the integration of patient-related information with pathogen properties, providing the base for scalable and comprehensive surveillance. The patient's symptoms during their sickness, along with existing risk factors and mutations in the pathogen’s genome, allow us to detect correlations that serve as a basis for testing causation and identifying new areas for public health measures.

Speaker: Felix Hartkopf (Robert Koch-Institut)

2:15 PM A customized, lightweight mobile laboratory vehicle for outbreak investigations with highly dangerous pathogens - experiences from a field trial in Germany

In an EU Horizon program funded project, a prototype of a mobile laboratory was developed, combining proven mobile units with advanced high-security laboratory architecture in a optimized space. This innovative, game-changing laboratory can be easily transported to remote outbreak areas, and swiftly set up as a fully functional diagnostic laboratory for processing human, veterinary, and environmental samples.
The laboratory is equipped with a central safety area. This zone is sealed from the external environment by a HEPA-filtered, negative pressure system, ensuring the safe and secure handling of highly pathogenic agents, such as risk group 3 (e.g. West Nile virus) and risk group 4 pathogens (e.g. Crimean-Congo hemorrhagic fever virus). Beyond its first-class safety features, the laboratory is an example of forward-thinking sustainability. Equipped with cutting-edge photovoltaic systems, it operates with ultra-modern, energy self-sufficiency, underlining a strong commitment to environmental responsibility and green energy solutions. To assess its operational readiness of the mobile laboratory, a field trial was conducted in Germany, which included collecting and analyzing bird feces samples for the presence of avian influenza (proof of concept study). For this purpose, detection methods for AI were successfully established within the mobile unit, and samples were analyzed and the results communicated to the responsible authorities.

Speaker: Markus Keller

2:30 PM NGS-based genomic surveillance of West Nile virus in a One Health framework

West Nile virus (WNV) circulates primarily in an enzootic transmission cycle between Culex mosquitoes and birds, with mammals serving as accidental hosts. Humans infections can be asymptomatic or lead to flu-like symptoms, severe neurological disease and even death. WNV has been found almost worldwide, with the number of infections in humans and animals in Germany increasing over the last seven years. In addition to WNV hotspot areas such as Berlin, the virus spread also to other major cities such as Leipzig, Hamburg and Dresden. In the study presented here, we analysed the whole genomes of 86 WNV isolates from diseased birds collected in 2023 and 2024 by a nationwide bird surveillance network coordinated by the FLI. The sequencing results were assessed phylogenetically and -geographically. All WNV strains detected in 2023-2024 belonged to known lineage 2 clusters, with no evidence of new introductions. Most bird cases were linked to subcluster 2.5.3.4.3c. Phylogenetic analysis dates the most recent common ancestor to mid-2018, supporting a single introduction followed by local endemic spread. A few sequences clustered in subcluster 2.5.3.2, indicating additional independent introductions. The detection of novel mutations in certain samples raises the possibility of viral adaptation to local hosts or changes in transmission dynamics, underscoring the need for continued genomic surveillance and epidemiological monitoring as part of a One Health approach.

Speaker: Ms Anne Schwarzer (Friedrich-Loeffler-Institut)

2:45 PM Assessment of Toxic Heavy Metals in Soil, Vegetables and Grasses Irrigated with Healthcare Wastewater and Associated Health Risks in the Akaki River Catchment, Central Ethiopia

Healthcare facilities generate wastewater that contain a variety of potentially toxic heavy metals, including lead (Pb), cadmium (Cd), chromium (Cr), and zinc (Zn), which are often discharged into nearby rivers. This study investigates the concentration of heavy metals in healthcare wastewater (HCWW) released into the Akaki River Catchment (ARC) and assesses its potential health and environmental impacts in central Ethiopia. Samples of HCWW, soil, selected vegetables, and grasses were collected from discharge points and adjacent irrigation areas. Tap and wastewater samples were analyzed for physicochemical properties and heavy metal content, while soil, vegetables, and grass samples were analyzed specifically for heavy metals using photometry and the Agilent 5800 ICP-OES instrument. The estimated daily intake (EDI) of heavy metals was calculated based on their concentrations in vegetables and the typical consumption rates of those vegetables and grasses. Except temperature, all the measured physicochemical parameters were surpassed recommended maximum limits (RML). In vegetable samples, the mean concentrations of Cd, Cr, and Pb (ranging from 1.82-4.23, 0.03-7.22, and 1.78-26 ppm, respectively) exceeded the RML established by the joint WHO/FAO guidelines. Lettuce and tomato exhibited the highest levels of Pb and Cd, while salad, carrot and beetroots were notably contaminated with Zn and Cr. In soil samples, the mean concentrations of Pb (34.13-35.36 ppm), Zn (7.66-8.6 ppm), and Cd (3.25-4.23 ppm) also exceeded FAO's RML. Likewise, in irrigated wastewater samples, the mean concentrations of Cr (3.71ppm), Cd (2.68ppm), and Pb (0.04ppm) surpassed the limits set by the US EPA guidelines. Grasses from irrigated areas also contained Pb, Cd, Cr, and Zn of 13.53, 2.16, 0.03 and 5.47 ppm concentrations respectively with Pb, Cd and Zn being above the recommended limits. The EDI, transfer health index (THI), and hazard index (HI) calculated for vegetables and grasses consumed by humans and livestock indicated elevated exposure, particularly for Pb, Cd, and Zn. In conclusion, the discharge of healthcare wastewater has compromised the suitability of river water for urban agriculture, livestock drinking, and the safe consumption of vegetables and animal products grown in wastewater-irrigated areas. Improving river water quality is crucial to mitigate potential health risks and to ensure the sustainable use of water resources.

Speaker: Dr Jirata Shiferaw Abosse (Addis Ababa University, College of Veterinary Medicine and Agriculture)

3:00 PM Genomic Characterization of Highly Pathogenic H5N1 Avian Influenza Viruses in Wild and Domestic Animals in Argentina Using a One Health Approach

In 2022, HPAI H5N1 clade 2.3.4.4b (B3.2 genotype) reached South America, causing poultry outbreaks, mass die-offs in marine mammals, and a severe human case in Chile, highlighting its zoonotic potential.
Through collaborative efforts between virologists, ecologists, and public/veterinary health agencies, full-genome sequences of H5N1 viruses in Argentina were generated and we identified two distinct B3.2 introductions. The first, in Feb 2023, via wild birds in the northwest, spreading southward and mainly affecting poultry (limited wildlife spillover). The second, in Aug 2023, entered via marine mammals in southern Argentina, spread north along the Atlantic coast, and caused mass mortality in elephant seals and sea lions.
We showed that viruses from this second wave belong to a distinct “marine mammal” subclade, carrying mammalian-adaptive mutations (PB2-Q591K, D701N) that may enhance transmission among them. We further identified that these viruses diversified into two sublineages with different geographic patterns and retained the ability to infect seabirds, indicating an expanding host range.
In Feb 2025, after nearly a year without outbreaks, we detected a novel triple reassortant H5N1 virus in backyard poultry. Our phylogenetic analysis revealed the first reassortment between H5N1 B3.2 and South American low pathogenicity avian influenza viruses, underscoring the need for continued surveillance and genome sequencing to monitor zoonotic HPAI H5N1 evolution in the region.

Speaker: Agustina Rimondi (Robert Koch-Intitut)

1:45 PM → 3:15 PM Session 8: Genomics & Proteomics

1:45 PM Evolutionary Dynamics of Bluetongue virus Strains Circulating in Italy, 2024-2025

In 2024, Italy experienced a major resurgence of Bluetongue (BT), a viral disease of ruminants caused by Bluetongue virus (BTV), an RNA virus circulating in multiple serotypes transmitted by Culicoides midges. By April 2025, over 7,000 confirmed cases had been reported, mainly involving serotypes BTV-3, BTV-4, and BTV-8. We performed whole-genome sequencing (WGS) and phylogenetic analyses on BTV strains collected across multiple Italian regions in 2024. Among the BTV-3 strains, we identified at least three distinct genomic constellations: two resulting from multiple reassortment events with other European strains, and one closely related to Northern European BTV-3. BTV-4 strains also displayed diverse genomic profiles, with individual gene segments of varied origin. BTV-8 showed up to 100% nucleotide identity in segment 2 with strains from France, suggesting likely spread via trade of viremic animals. Moreover, BTV-8 genome segments were found within both BTV-3 and BTV-4 strains, highlighting the role of reassortment in shapingBTV evolution. These findings reveal the complex genomic landscape of BTV in Italy and emphasize the value of WGS for monitoring viral dynamics.

Speaker: Gloria Plebani (Università degli Studi di Teramo, Istituto Zooprofilattico Sperimentale Abruzzo Molise-Teramo)

2:00 PM Nanopore-Based Methylome Profiling of Microbial Communities

The methylome, defined as the complete set of genome-wide methylation marks, provides an additional layer of information beyond the genetic sequence, yet remains largely underexplored in bacterial genomics. Recent advances in Nanopore sequencing now allow investigation of DNA methylation not only in isolates but also at the community level, opening new opportunities to study epigenetic variation in complex microbiomes and better understand microbial ecology and adaptation.
We are analyzing the metagenome and the metamethylome of seal microbiomes using Nanopore sequencing, as part of a project investigating antimicrobial resistance (AMR) acquisition on those sentinel species. By applying state-of-the-art ONT basecalling tools combined with in-house pipelines, we examine how DNA methylation varies across species and strains. A complementary study investigates Klebsiella pneumoniae isolates from wastewater, providing insights into how methylation patterns differ between environmental populations and those from host-associated communities.
Beyond biological insights, we aim to integrate methylation data into metagenomic workflows. We assess how methylation can improve early-stage classification by filtering out eukaryotic sequences and enhancing binning accuracy, especially in linking mobile genetic elements like plasmids to host genomes. These efforts contribute to a deeper understanding of epigenetic mechanisms in AMR and support a broader One Health approach connecting environmental, animal, and human health.

Speaker: Valentina Galeone (RKI)

2:15 PM Combining Short- and Long-Read Sequencing to Investigate a Ralstonia pickettii Outbreak Linked to Contaminated Saline Solutions

In December 2023, the WHO reported a Ralstonia pickettii outbreak in Australia linked to contaminated saline solutions. Concurrently, German surveillance detected an increase in nosocomial R. pickettii bacteremia cases, prompting a national outbreak investigation.

From August 2023 to June 2024, 15 patient isolates were sequenced using Illumina whole genome sequencing. Five of these were additionally sequenced using Oxford Nanopore Technology (ONT). Combining short- and long-read data enabled the reconstruction of complete genomes. Similarities to publicly available data were assessed with core genome multilocus sequence typing (cgMLST), using a newly created scheme.

Six isolates from patients in three hospitals across different federal states clustered within ≤6 allele differences. German and Australian outbreak clusters differed by at least 43 alleles, requiring further investigation into their potential link.

Rapid genomic investigation enabled cluster identification and assessment of relatedness to the other outbreaks, supporting epidemiological investigation. The absence of a standardized cgMLST scheme, limited public data, and sparse documentation of analyses in prior studies posed key challenges. Although, ONT allowed the recovery of complete genomes and plasmids, its increased error rates inflated cgMLST distances, highlighting the usefulness of combined long- and short-read data for bacterial outbreak investigations.

Speaker: Dr Vladimir Bajić (Genome Competence Centre (MF 1), Robert Koch Institute, Berlin, Germany)

2:30 PM Multi-omics investigation of L-sorbose metabolism in high-risk Escherichia coli lineages linking fitness and virulence

Certain sequence types (STs) of Escherichia coli, such as ST131 and ST648, belong to high-risk clonal lineages that pose serious public health threats by combining antimicrobial resistance (AMR), fitness, and virulence. In contrast, other subtypes e.g., ST10 are typically harmless and beneficial colonizers. To identify characteristics beyond AMR, we analyzed over 22,000 E. coli genomes and discovered the L-sorbose (sor) phosphotransferase system (PTS) as a marker enriched in high-risk lineages but nearly absent in commensals. Multi-omics analyses revealed sor-dependent induction of the sor PTS and activation of associated pathways including motility, capsule biosynthesis, and purine and tryptophan metabolism. Functional validation via knockout mutants confirmed a fitness advantage linked to the sor-operon. Notably, introducing the operon into a commensal strain increased virulence in the Galleria mellonella model. The widespread presence and induction of the sor-PTS in high-risk clones highlight its potential role in linking metabolism, fitness, and virulence. Further studies, including in vivo models, are planned to elucidate its potential as a pathogen-specific target for alternative therapies. Such targeted strategies may reduce antimicrobial use and thereby resistance selection, supporting One Health goals by limiting AMR emergence and spread across human, animal, and environmental sectors.

Speaker: Lena-Sophie Swiatek

2:45 PM H7 highly pathogenic avian influenza A virus genomes from the first half of the 20th century

Highly pathogenic avian influenza viruses (HPAIV) cause severe outbreaks in poultry, leading to high mortality, economic losses, and occasional human infections. While H5 and H7 subtypes have dominated poultry outbreaks in the 20th century, the genomic diversity of HPAIV before widespread surveillance in the 1980s remains poorly characterized. So far, only a few complete genomes from before 1950 have been sequenced.

Historical pathology collections provide a unique window into the evolutionary history of pathogens and are a valuable resource for studying ancient HPAIV. To explore early HPAIV diversity, we analyzed 30 formalin-fixed avian tissue samples from the 1920s to 1960s, sourced from four historical pathology collections.

Using shotgun RNA sequencing, we detected HPAIV reads in five samples and reconstructed two near-complete genomes: H7N1 (1927) and H7N7 (undated). Three additional samples (1942–1960) yielded lower coverage genome-wide data. Interestingly, three specimens originally diagnosed as avian influenza only contained Newcastle disease virus sequences.

We are currently working to complete genome recovery from all HPAIV-positive samples. The resulting dataset will support phylodynamic analyses to reconstruct the history of HPAIV lineages and refine the evolutionary timeline of avian influenza viruses.

Speaker: Dr Annika Graaf-Rau (Department of Pathogen Evolution, Helmholtz Institute for One Health, Greifswald, Germany)

3:00 PM Automatic sequential clustering in the context of integrated genomic surveillance

Integrated Genomic Surveillance (IGS) enables the surveillance of various, public health-relevant bacterial and viral pathogens. For bacterial species, the identification of genomic clusters represents the foundation for outbreak investigations and epidemiological studies. Providing well-defined genomic clusters therefore represents an essential task of IGS, in order to support the surveillance of relevant bacterial species by the federal and local health authorities in Germany.

For the automatic computation and definition of genomic clusters, a diverse set of challenges has been identified: the dependence on external data silos should be minimized, the clustering and its nomenclature should be robust over time and the clusters should represent meaningful groupings, even in the presence of samples with lower quality (e.g. missing data).

Within this work, these challenges are addressed and advantages as well as disadvantages of some possible solutions are highlighted and discussed. Finally, the current analytical approach and the software implementation utilized within the IGS project, termed Seqsi (SEQuential SIngle-linkage clustering), is presented.

Speaker: Torsten Houwaart (Genome Competence Centre (MF1), Robert Koch Institute, Berlin, Germany)

3:15 PM → 3:45 PM Keynote IV: Andrea Winkler: 10 recommendations for a better life: The Lancet One health Commission Report.

Convener: Farbian Leendertz

3:45 PM → 5:15 PM Scientific Speed Dating

Convener: Sascha Knauf

5:15 PM → 6:00 PM Coffee & Poster Viewing II

6:00 PM → 7:30 PM Members Assembly & Election SAB

8:00 PM → 10:30 PM Conference Dinner

10:30 PM → 11:59 PM Party (aka "Music, Table Tennis & Drinks")

Wed, October 15

8:30 AM → 9:00 AM Registration

9:00 AM → 9:30 AM Keynote V: Mirjam Jenny: Health communication and human health behavior in times of climate change

9:30 AM → 11:00 AM Session 9: One Health in Public Health II

Conveners: Michaela Projahn, Katharina Schaufler

9:30 AM From Field to Genome: Genomic characterization of pneumococcal strains circulating at the human-wildlife interface in Sub-Saharan Africa

Lower respiratory tract infections are among the leading causes of death for children under five in Sub-Saharan Africa, with Streptococcus pneumoniae being the most common causative agent. Beyond its public health impact, S. pneumoniae has been shown to have implications for the conservation of endangered species, as humans have inadvertently transmitted the bacteria to wild great apes resulting in lethal outbreaks. Understanding serotype diversity and antimicrobial resistances at a local scale can guide tailored public health interventions, such as the selection of appropriate vaccines and antibiotic treatment, which can reduce disease burden and the risk of transmission to wildlife.

We conducted genomic characterization of pneumococcal strains carried asymptomatically by humans living and working in proximity to great apes in Taï National Park, Côte d’Ivoire, and Dzanga-Sangha Protected Areas, Central African Republic. A total of 473 nasopharyngeal swabs were collected; from these, 43 S. pneumoniae strains were isolated directly in the field using a solar-powered incubator. Molecular and genomic analyses were performed at the Institut Pasteur de Bangui, Centre Hospitalier Universitaire de Bouaké and the Helmholtz Institute for One Health in Greifswald. We revealed the circulation of multiple serotypes, including both vaccine-covered and non-covered types, and the presence of distinct antimicrobial resistance patterns. This study highlights how genomic surveillance can provide relevant data to inform prevention and treatment policies within a One Health framework.

Speaker: Moritz J.S. Jochum (Helmholtz Institute for One Health)

9:45 AM Anthrax outbreak associated with handling and consuming meat from animals that died suddenly, Kanungu District, Uganda, June–November 2024

Background: Anthrax is a recurrent zoonotic threat in Uganda, with eleven outbreaks reported in 2024. On September 17, 2024, the Ministry of Health confirmed two human anthrax deaths in Kanungu District–the first recorded outbreak in the district. We investigated to determine the scope, identify risk factors, and recommend evidence-based control measures.
Methods: We defined a suspected cutaneous anthrax case as skin lesions (papule, vesicle, or eschar) with ≥2 of skin itching, reddening, lymphadenopathy, fever, or malaise. Suspected gastrointestinal anthrax was abdominal pain with ≥2 of vomiting, diarrhea, fever, or loss of appetite in Kanungu residents (June 1–November 4). Confirmation required PCR detection of Bacillus anthracis. In a 1:2 unmatched case-control study, we enrolled all cases and asymptomatic neighbors from the two most affected sub-counties. Logistic regression identified risk factors.
Results: We identified 90 cases (86 suspected and 4 confirmed); 80% cutaneous, 11% gastrointestinal, 9% both. Males were more affected (AR=48/100,000) than females (AR=15/100,000). The case fatality rate was 6.7%. Bugongi (AR=257/100,000) and Katete (AR=224/100,000) were most affected. Risk factors included consuming meat from suddenly dead animals (aOR=5.8, 95% CI: 2.7–12.0), handling their carcasses (aOR=9.3, 95% CI: 2.5–15.0), and lower education (aOR=6.2, 95% CI: 2.5–15.0). Most cases bought meat from one butcher sourcing such animals.
Conclusion: The outbreak was linked to consuming and handling meat from animals that died suddenly. We recommend mandatory pre-slaughter inspections, safe carcass disposal, and targeted community education.

Speaker: Charity Mutesi (Uganda National Institute of Public Health)

10:00 AM Evaluating response to an anthrax outbreak using 7-1-7 metrics in Southwestern Uganda, September 2024

Background
Uganda has responded to 37 anthrax outbreaks in the past decade. In 2021, the country adopted the 7-1-7 framework which stipulates outbreak detection in 7 days, notification in 1 day and completion of early response actions in 7 days. Kanungu District at the border with Democratic Republic of Congo (DRC) reported its first known anthrax outbreak on September 17, 2024. We assessed response to this outbreak using the 7-1-7 approach.

Methods
We used the 7-1-7 metrics to document the dates of emergence, detection, notification, and completion of early response actions. We held discussions with the district leadership, health workers, and community members to establish key dates and facts, and to identify bottlenecks and enablers. Qualitative data were organized into themes to capture bottlenecks and enablers.

Results
The disease emerged in animals on June 15, 2024 and was detected after 85 days. In humans, the time from emergence (June 26, 2024) to detection was 77 days. The district One Health Team was notified 1 day after detection. Early response actions were jointly initiated after 5 days and completed in 13 days for human health, and in 14 days for animal health. Overall, the outbreak involved 111 sudden animal deaths, and 90 human anthrax cases with 6 (6.7%) human deaths. Enablers for immediate notification included presence of a real-time One Health communication platform for health workers. Bottlenecks included weak zoonotic disease surveillance characterized by understaffing, low suspicion index for anthrax, and weak coordination with private health facilities.

Conclusion
The response to Kanungu District’s first documented anthrax outbreak met only one (notification) of the 7-1-7 timeliness targets, facilitated by an existing real-time One Health communication platform. This study reveals missed opportunities for early detection and response, posing potential cross-border health risks. The findings underscore the need to adopt the 7-1-7 framework within Uganda’s animal health sector and to strengthen One Health coordination, event-based surveillance, and frontline veterinary capacity in high-risk areas

Speaker: Dr Hannington Katumba (Uganda National Institute of Public Health)

10:15 AM One Health in Austria: What agencies can do to implement international recommendations at national level

Inter-agency collaboration involves cooperation and/or coordination between two or more institutions or within components of the same institution. This collaboration can be defined as any joint activity that achieves a greater public benefit than if the institution were to act alone. Complex challenges such as climate change and preserving the health of humans, animals, plants and the environment require structured and holistic solutions enabled by systemic thinking.

Expert organizations such as AGES (Austrian Agency for Health and Food Safety) and GÖG (Austrian National Public Health Institute) make a significant contribution to health and health maintenance in Austria. Nevertheless, there are health threats that cannot be solved separately, as became clear during the COVID-19 pandemic. Even before, but especially during the pandemic, there was increased cooperation. The ad hoc structures and activities created were successful in the short term but were not a solution in the medium and long term, as the focus was exclusively on SARS-CoV-2.

In order to respond better, faster and more efficiently to future threats, the WHO recommends using the inter-pandemic periods for cross-institutional cooperation. These phases offer the opportunity to improve coordination and resource management, to make the exchange of information more effective and to develop joint strategies and measures - at global, regional and national level.

For this reason, AGES and GÖG began working on a joint memorandum of understanding and cooperation agreement on One Health at the end of 2024 and it was signed beginning of 2025. As part of a task force, a common understanding of One Health is being developed, within a joint workshop common One Health topics were identified and next workflows agreed on. This structured collaboration is the first step towards an integrative One Health strategy for Austria.

Speaker: Barbara Kovacs (AGES, Österreichische Agentur für Gesundheit und Ernährungssicherheit)

10:30 AM Screening of shrews for Borna disease virus 1 (BoDV-1) and its implications for public health management

Borna disease virus 1 (BoDV-1) causes mostly fatal encephalitis in humans and other mammals. Its distribution area is restricted to parts of Southern and Eastern Germany, Austria, Switzerland and Liechtenstein. Spillover to dead-end hosts results from direct and/or indirect contact to bicolored white-toothed shrews (Crocidura leucodon), the natural BoDV-1 reservoir, which shed the virus via urine, feces, saliva and skin, but remain unaffected by the disease.
As part of this project, 263 shrews, predominately from Bavaria, were tested for BoDV-1 and their species was determined by a newly established RT-qPCR assay targeting the cytochrome b gene. Twenty-four (26.4%) of 91 C. leucodon as well as one out of 11 (9.1%) Mediterranean water shrews (Neomys anomalus) tested positive for BoDV-1, all of which originated from Bavaria. Phylogenetic analyses demonstrated the BoDV-1 sequences to belong to the same local clusters as found in Borna disease cases in the respective regions.
Several BoDV-1-positive shrews were found in human dwellings. Environmental samples were collected in five instances two to four weeks later, revealing low levels of BoDV-1 RNA but no infectious virus. In two cases, submitters had experienced close contact to excretions of BoDV-1-positive shrews, initiating post-exposure prophylaxis and 12-months of monitoring.
This One Health approach refines BoDV-1 risk areas and provides valuable insights into the poorly defined human-animal interface of BoDV-1 infection.

Speaker: Lea Lenhard (Institute of Diagnostic Virology, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, Greifswald - Insel Riems, Germany; Bavarian Health and Food Safety Authority, Munich, Germany; Zoonotic Bornavirus-Focal Point Bavaria (ZooBoFo) 2.0, Germany)

10:45 AM Psychological impact and perceived mpox risk among frontline healthcare workers during early epidemic phase, Uganda, August–September, 2024

On July 24, 2024, Uganda confirmed its first mpox outbreak, with initial cases detected in Kasese and Mayuge Districts. As a newly emergent disease, mpox posed unfamiliar clinical and operational challenges for healthcare workers (HCWs), whose limited experience and stigma surrounding the illness risked eroding confidence and undermining psychological well-being. To guide tailored support measures, we assessed risk perception and psychological distress among HCWs. We conducted a cross-sectional study during August–September 2024. Self-administered questionnaires were filled out by consenting day-shift HCWs: sociodemographic, occupational behaviors, perceived risks, and psychological distress variables. We determined the prevalence of psychological distress as the proportion of HCWs with a General Health Questionnaire score >12. A higher score from the 25 concern statements signified a higher degree of risk perception. We identified associated factors using modified Poisson regression. Overall, 339 HCWs participated at an 80% response rate; 215 (63%) were female, and 253 (75%) were aged 18-35 years. HCWs, 208 (61%), reported a moderate level of perceived risk. The prevalence of psychological distress was 26% (n=88, 95%CI=17–35%). Moderate perceived mpox risk (aPR=10, 95%CI=2.5–37) and high perceived risk (aPR=14, 95%CI=3.6–56) were associated with psychological distress. HCWs lacking infection prevention and control (IPC) confidence (aPR=1.2, 95%CI=1.0–1.5) and those without a clear health facility IPC plan (aPR=1.3, 95%CI=1.1–1.6) had increased likelihood of psychological distress. Psychological distress was common among HCWs during the study period, driven by perceived mpox risk and inadequate IPC measures. There’s a need to combine mental health support with strengthened IPC protocols through hands-on training and clear operational guidelines to protect HCW well-being and maintain uninterrupted service delivery during mpox and future outbreaks.

Speaker: Mrs Joyce Owens Kobusingye (Uganda National Institute of Public Health)

9:40 AM → 11:10 AM Session 10: Vaccines & Immunology + Novel Methods + AI in Health Research

Conveners: Michael Mühlebach, Torsten Semmler

9:40 AM Development of broadly protective Outer Membrane Vesicle based intranasal betacoronavirus vaccine

Background: After the initial outbreak of SARS-CoV-2, other (partially) immune escape variants appeared rapidly highlighting the need to develop a vaccine that offers a broader protection not only against SARS-CoV-2 variants but also to other members of the betacoronavirus genus. Furthermore, the present SARS-CoV-2 vaccines are administered intramuscularly and do not elicit mucosal immunity, which is deemed important for protection against SARS-CoV-2 infections.
Objective: Here, we develop a new intranasal pan-Betacoronavirus vaccine using Intravacc’s established Neisseria meningitis derived Outer Membrane Vesicles (OMV), where the vesicle serves as carrier for viral antigens.
Methods and Results: As a first step, 75 candidates consisting of full spikes, chimeric spikes and Receptor Binding Domain concatemers (RBDs) were designed using 4 sarbecoviruses, 3 merbecoviruses and 4 embecoviruses pre- selected spike sequences. 44 proteins were successfully synthesized and screened by Enzyme linked immunosorbent assay (ELISA) using human sera that were pre-characterized for high titre-pan-coronavirus reactivity by Immunofluorescence assay (IFA). Subsequently, a pool of 22 vaccine candidates consisting of high and low reactive spikes along with 3 binary combinations of proteins were recommended for mice immunogenicity study. For the immunogenicity study, 10 BALB/cOlaHsd mice were vaccinated intranasally on day 0 and day 21 with 20µl of vaccine. The mice were sacrificed on day 35 under anaesthesia and their sera and lung homogenate were analysed. Pooled sera from the mice immunogenicity study were tested for neutralization (1:10-1:1280) against SARS-related CoV, SARS-CoV-2 and MERS-CoV Vesicular stomatitis virus pseudo_particles (VSVpp). Neutralization data showed that 4 candidates; a trimeric RBD concatemer, a hexameric RBD concatemer and 2 binary combination candidates consisting of MERS spike proteins and sarbecovirus tetrameric RBDs elicited broad neutralization until 1:1280 dilution of sera against all 3 above mentioned VSVpp. Furthermore, ELISAs performed for the same candidates with lung homogenate confirmed the presence of IgA and IgG antibodies (102-104). Currently, animal challenge studies for the selected candidates are in progress.
Conclusion: This new platform of intranasal pan corona vaccine can offer early robust mucosal protection against betacoronavirus infections and has the potential for expansion to other novel corona viruses in the future.

Speaker: Dr Kaneemozhe Harichandran (Charité-Universitätsmedizin Berlin, Institute of Virology, Germany)

9:55 AM Development and Evaluation of a Bivalent Vaccine Candidate for the Protection of Pigs against Infections with Pseudorabies and Nipah Virus

Nipah virus (NiV) infections pose a serious health risk to humans and livestock in Southeast Asia (SEA). Due to its high fatality rate in humans, the absence of licensed vaccines or therapies, and its likelihood to cause severe outbreaks, NiV has been added to WHO’s Blueprint list of ‘priority diseases’. Here, we developed a bivalent vaccine candidate to protect pigs simultaneously from infections with pseudorabies virus (causing Aujeszky’s disease) and NiV, both circulating in SEA, by engineering the live attenuated PrV vaccine strain Bartha K61 to co-express NiV F and G glycoproteins. Immunogenicity in pigs has been successfully demonstrated by analysis of NiV- and PrV-specific T-cell and antibody responses.
Based on these data, the protective effect in pigs against infections with PrV and NiV will now be assessed. First, the NiV infection model in pigs was established in the high containment animal unit at the FLI. Twelve pigs at the age of 10-12 weeks were infected oronasally with NiV, and were observed for up to 22 days. No severe clinical signs were monitored, confirming findings from published studies. Animals were sampled daily until 10 days post infection (dpi) to assess viremia, viral shedding and immune responses. Necropsies of two pigs each were performed at 4,5,7,8,21 and 22 dpi to analyze the progression of viral dissemination especially at early time point after inoculation. These data will allow a targeted sampling during the planned vaccine efficacy studies.

Speaker: Anne Balkema-Buschmann (Friedrich-Loeffler-Institut, Bundesforschungsinstitut für Tiergesundheit)

10:10 AM Magnetic bioprinted granuloma: a three-dimensional model for cattle tuberculosis

Tuberculosis (TB) continues to represent a significant global health concern, impacting both humans and livestock. Mycobacterium bovis is the causative agent of bovine TB, an important zoonosis, whereas Mycobacterium tuberculosis, an organism adapted to humans, can occasionally cause symptomatic infection in cattle. The formation of granulomas, defined as organized multicellular tissue lesions, has been identified as a hallmark of TB in all affected host species. We developed a three-dimensional granuloma model, termed in vitro granuloma-like structure (IVGLS), using bovine leukocytes and magnetic nanoshuttles. Stable IVGLS were bioprinted to resemble either TB granulomas at innate stage, composed of macrophages, or the adaptive stage, containing also lymphocytes. M. bovis Bacillus Calmette-Guérin (BCG) replicated within the IVGLS, inducing foamy cell formation and triggering apoptosis particularly in the presence of lymphocytes. IVGLS released chemokines and Th1 cytokines and rewired their metabolism towards glycolysis. Cattle IVGLS recapitulate features of TB granulomas and facilitate spatial mapping of the immune responses.

Speaker: Anca Dorhoi

10:25 AM Establishing a human stem cell-derived infection model to visualize the effects of Listeria monocytogenes on the developing brain

Zoonotic infections during pregnancy, especially those involving the central nervous system, are associated with an increased risk for neurodevelopmental disorders in offspring. Listeria monocytogenes is a key example, with prenatal exposure linked to long-term neurological impairments. To investigate underlying pathogenic mechanisms, we employed a human induced pluripotent stem cell (iPSC)-derived neurosphere model that mimics key aspects of fetal brain development.
A standardized infection protocol was implemented: Bacteria were cultured to 10⁸ CFU/mL (OD 0.5) and applied at multiplicities of infection (MOI) of 50, 100, and 150 for 1–4 hours. Following gentamicin treatment to eliminate extracellular bacteria, neurospheres were fixed at 1, 24, and 48 hours post-infection. Infection was validated via immunofluorescence using Listeria-specific antibodies and Phalloidin to label actin filaments. Variable invasion patterns were observed across conditions, reflecting clinical heterogeneity. All MOIs supported successful infection; MOI 50 was selected for subsequent analyses, as it more closely reflects physiologically relevant infection levels. Infections were more consistent following 2-hour exposures compared to 1 hour. Viability exceeded 80% and cytotoxicity remained below 5% of controls, indicating the model’s suitability for studying host-pathogen interactions without compromising neurosphere integrity.
Ongoing studies will evaluate infected cell populations, proliferation, migration, and electrophysiological alterations.

Speaker: Annika Fischer (Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany; Institute of Food Quality and Food Safety, University for Veterinary Medicine Hannover, Hannover, Germany; Charité – Universitätsmedizin Berlin, Einstein Center for Neurosciences Berlin, Berlin, Germany)

10:40 AM Towards Real-Time Detection of COVID-19 via Untargeted Volatile Organic Compound Profiling Using Online Gas Chromatography-Ion Mobility Spectrometry

Volatile organic compounds in exhaled breath reflect metabolic alterations during viral infection, offering potential for rapid SARS-CoV-2 detection. We developed an online gas chromatography-ion mobility spectrometry (GC-IMS) method for direct breath analysis from 119 participants with RT-PCR confirmed COVID-19 status. Participants breathed directly into the GC-IMS instrument (STEP, Pockau, Germany) through a mouthpiece for 4 seconds, followed by 209 seconds analysis. The system utilizes a 20-meter MXT-5 GC column (at 60°C) with tritium IMS detector operating at 400 V/cm. Measurements at ambient conditions use filtered air as drift gas. Ambient air samples enable background subtraction reducing environmental confounding. The platform achieves ppb-ppt detection limits with a computational pipeline for spectral processing and analysis. Comprehensive metadata including dietary intake accounts for confounding factors. This untargeted approach aims to classify COVID-19 patients using machine learning on breath VOC profiles. Previous experimentation distinguished antibiotic-resistant bacteria with similar instrumentation (MCC-IMS) in in vitro tests. The method provides rapid (< 4 minutes ), non-invasive screening with real-time results, offering potential for point-of-care diagnostics and high-throughput pandemic applications.

Speaker: Deevanshi Walia (Fraunhofer IZI)

10:55 AM Tackling One Health risks – From current practice to future perspectives

Microbial Risk Analysis (MRA)—comprising risk assessment, risk management, and risk communication—plays a pivotal role in protecting public health and ensuring food safety across the globe. Yet, the accelerating transformation of food systems, the emergence of novel microbial hazards, and the growing recognition of One Health interdependencies increasingly challenge the effectiveness of traditional MRA frameworks. Globalization, climate change, antimicrobial resistance, and biodiversity loss are reshaping the dynamics of pathogen emergence and transmission along the human-animal-environment interface, demanding risk analysis approaches that are flexible, adaptive, and fit for these complex realities.
In this contribution, we critically examine the current state of microbial risk analysis and explore pathways toward its future evolution in line with the One Health paradigm. Drawing on a systematic literature review, insights from a global survey of food industry professionals, and a computational proof-of-concept study using AI-based agent modeling, we provide an integrated perspective on methodological gaps, practical challenges, and opportunities for innovation. Our findings confirm that Codex Alimentarius-aligned risk assessment remains the prevailing standard. However, across sectors, there is a growing call for participatory and integrated approaches capable of addressing the complexity of emerging risks and diverse food system contexts. Survey results highlight substantial variation in risk perceptions, implementation strategies, and decision-making processes, particularly influenced by company size, regulatory environments, and geographic region. Misconceptions such as the belief in the feasibility of “zero risk” further emphasize the need for improved communication and stakeholder engagement.
To help bridge these gaps, we showcase the potential of AI-supported, agent-based modeling to facilitate transparent risk negotiation and consensus-building across stakeholder groups. By aligning scientific rigor with inclusive, participatory processes, we argue that MRA can be strengthened as a central pillar of One Health, supporting informed decision-making and balanced solutions in the face of complex, cross-sectoral challenges. Our work advocates for the evolution of microbial risk analysis into a dynamic, collaborative, and digitally empowered discipline—better prepared to address the interconnected risks of our shared ecosystems.

Speaker: Dr Alexandra Fetsch (Competence Centre for Food Safety, Chair of Food Microbiology, LMU Munich)

11:10 AM → 11:30 AM Coffee & Poster Viewing

11:30 AM → 1:00 PM Session 11: Emerging Pathogens III + Conservation & Wildlife

Conveners: Fabian Leendertz, Magdalena Meyer

11:30 AM Comparative Immune Responses to Pathogenic and Non-Pathogenic Mammarenaviruses in Human and Reservoir-Derived Antigen-Presenting Cells

Mammarenaviridae is a genus of ambisense RNA-viruses, with members that cause viral hemorrhagic fever, namely Lassa virus (LASV) and Lujo virus (LUJV) and members that have not been associated with disease, such as
Mopeia virus (MOPV). LASV infection results in 5000 to 10,000 deaths annually in sub-Saharan Africa, and LUJV has a case-fatality rate of up to 80%. The Natal multimammate mouse (Mastomys natalensis, NMM) has been identified as a natural reservoir of LASV and MOPV. However, these animals do not show clinical signs upon infection. In humans, LASV targets dendritic cells (DCs) and macrophages (MΦs), among other cells, and induces activation and maturation of DCs, but downregulates interferon response and fails to induce robust T-cell responses.
Given the lack of pathology of LASV infection in NMM, and the pivotal role of DCs and MΦs in the disease development in humans and non-human primates, the purpose of our study is to compare the immune profile of human and NMM-derived DCs and MΦs responses LASV, LUJV and MOPV infection. We differentiated DCs and MΦs from bone-marrow cells isolated from adult NMM or human monocytes and infected them with LASV, LUJV or MOPV. We sampled cells and supernatants at 2 days post-infection. As controls for the activation of the innate immune response in these cells, we stimulated the cells Sendai virus (SeV). We performed a characterization of immune profile of the cells the cells,
measured the transcript levels of immune-related genes and quantified viral loads. We describe the comparative immune-profile resulting of the infection with pathogenic vs. non-pathogenic Mammarenaviruses, in human and in a natural reservoir species. This gives us insights on the mechanisms of pathogenesis in humans and protection for the natural reservoir species. This highlights the importance on the insights on the immune mechanism that lead to a non-pathogenic infectious phenotypes and the relevance for natural reservoir's further studies.

Speaker: Nicolas Corrales (Robert Koch Institut)

11:45 AM Genomic characterization and mapping of molecular factors driving the increased replication fitness of Arabian MERS-CoV lineage B5

MERS-CoV is a highly pathogenic Betacoronavirus with a ~36% case-fatality rate and a zoonotic origin in dromedary camels. Clade B strains circulate in the Arabian Peninsula and are the primary cause of severe human infections, leading to sporadic outbreaks. In recent years, different clade B lineages have emerged, with lineage B5 replacing other clade B strains in the Middle East. Lineage B5 strains exhibit increased replicative fitness, higher resistance to type I interferons (IFNs), and reduced host immune activation, indicating enhanced viral fitness. Comparative genomic analyses with lineages B3, B4, and the EMC strain (clade A) reveal that B5 strains accumulate genetic changes, particularly in nsp3 and the Spike gene. To identify genetic determinants of B5 fitness, we used a reverse genetic system based on transformation-associated recombination (TAR) cloning. This system enables precise mapping of functional differences between recombinant MERS-CoVs. We generated 12 chimeric viruses by systematically exchanging genomic fragments between a lineage B5 strain and EMC. These were screened for replicative competence in Calu-3 cells, with or without type I IFN pre-treatment. Initial results suggest that genetic polymorphisms acquired in nsp3 and Spike could be responsible for the enhanced virulence of lineage B5 strains. Further assays are currently ongoing to depict specific virulence mechanisms and link them to fixed polymorphisms in B5 strains.

Speaker: Annika Beyer (Charité Institut für Virologie, Humboldt Universität zu Berlin)

12:00 PM Deciphering Lineage-Specific Determinants of Usutu Virus through Targeted prM/E Substitutions

Usutu virus (USUV) is an emerging mosquito-borne flavivirus that primarily affects birds but can also cause neuroinvasive disease in humans. Despite the growing number of outbreaks and increasing concern, many aspects of its biology remain poorly understood. Several viral lineages have been identified, but a systematic comparison of mutations within the pre-membrane (prM) and envelope (E) proteins has not yet been conducted. To investigate the functional impact of prM/E protein variations, we engineered a panel of six recombinant USUV strains using a common genetic backbone derived from aEU2 lineage strain. Within this conserved scaffold, the prM/E coding regions were replaced by reverse genetics with those from representative lineages, allowing for an in-depth evaluation of lineage-specific differences in these critical structural proteins. The resulting viruses are being extensively characterized in vitro in mammalian and mosquito cell lines, and in vivo experiments have been planned. Additional characterization is being conducted in ovo to explore infection dynamics in a vertebrate model. Embryonated chicken eggs are sampled over 5 days, and tissues are harvested for downstream analyses. Altogether, this comprehensive dataset is expected to provide valuable insights into the effects of prM/E mutations on key viral traits, contributing to a better understanding of USUV pathogenesis, host interaction, and lineage-specific phenotypes.

Speaker: Marialuigia Caporale (Experimental Zooprophylactic Institute of Abruzzo and Molise (IZSAM), Teramo, Italy. PhD National Programme in One Health approaches to infectious diseases and life science research, Departiment of Public Health, Experimental and Forensice Medicine, University of Pavia, Pavia, 27100, Italy)

12:15 PM Prevalence and associated factors of post-traumatic stress disorder, depression and anxiety disorders among mpox survivors, Uganda, 2024

Background: Mpox was declared an epidemic in Uganda on July 24, 2024. By December 30, 2024, approximately 800 mpox cases were reported across 53 districts, with Kampala Metropolitan Area (KMA) bearing two-thirds of the burden. Mpox response in Uganda is still deficient in aspects of mental health support to case-patients or survivors. We assessed the prevalence and associated factors of anxiety, depression, and posttraumatic stress disorder (PTSD) among mpox survivors in the most affected districts in Uganda.
Methods: This was a cross-sectional community-based study conducted from February 1–28, 2025. We selected respondents using simple random sampling of survivors from Kampala, Mukono, and Wakiso districts. The sampling frame were the lists of survivors from each of the 3 districts. Random numbers generated from excel were used to select participants for the study. Sample size was determined using Kish Leslie formula assuming a 50% prevalence of mental health disorder among survivors. Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale, while PTSD was evaluated with the PTSD Checklist DSM-5. Associated factors for each condition were determined using modified Poisson regression. The threshold for probable presence based on reported symptoms (caseness) for anxiety and depression was 8 and that of PTSD was 38.
Results: We enrolled 385 participants with a median age of 29 years (IQR: 25–35). A total of 230 (60%) were female, and 136 (59%) of these were female sex workers. The caseness prevalence of anxiety was 11% (95%Cl 8%–14%), depression was 14% (95%CI 11%–18%) and PTSD was 9% (95%CI 6%–12%). The general caseness prevalence of mental health disorders among mpox survivors was 22% (n=84; 95% CI 18%–26%). Factors associated with increased prevalence of mental health disorders were longer stay (>14 days) at the treatment unit (aPR=2, 95%CI 1.3–3.1), reports of poor management at the treatment unit (aPR=2.7, 95%CI 1.3–3.1), having suffered moderate (aPR=2.2, 95%CI 1.2–4.3) or severe (aPR=5.6, 95%CI 3.1–10.2) symptoms of mpox and having suffered stigmatization from society (aPR=2.2, 95%CI 1.4–3.6).
Conclusions: Approximately 2 in 10 mpox survivors surveyed experienced significant symptoms of a mental health disorder during the illness or recovery. These findings underscore the need for integrated mental health and psychosocial support in mpox outbreak responses to address the psychological impacts of affected persons.

Speaker: Emmanuel Okiror Okello (Uganda Public Health Fellowship Program, Uganda National Institute of Public Health, Kampala, Uganda)

12:30 PM 90 kDa ribosomal S6 Kinase 1 influences endosomal acidification during Influenza A virus infection

RSK kinases belong to the downstream targets of the classical MAPK/ERK pathway, which contributes to the release of the influenza virus (IV) genome via endosomal acidification. Here we show for the first time, that the kinase isoform RSK1 is also involved in this process.
Inhibition of RSK with the inhibitor BI-D1870 or siRNA mediated knockdown of RSK1 resulted in a decreased internalization of VSV-pseudotyped H1N1 viruses as well as endosomal acidification (EA). Super resolution microscopy (STED) and proximity ligation assays (PLA) revealed that not only ERK but also RSK1 colocalizes with the late endosomal marker CD63.
EA is controlled by v-ATPases which are phosphorylated by ERK or PI3K. We hypothesized that RSK1 also takes part in this process and found colocalization of RSK1 with the v-ATPase subunit A.
In conclusion, this work demonstrates, that RSK1 is misused by human IV and HPAIV in an isoform specific manner to promote the release of the viral genomes in the cytoplasm.

Speaker: Nicole Oberberg (Institute of Virology, UKM Münster)

12:45 PM Detection of Nairobi Sheep Disease Virus in Goats and Sheep and of Two Previously Unknown Nairoviruses in Rodents and Shrews in Uganda’s Albertine Rift

The genus Orthonairovirus contains tick-borne viruses with public and veterinary health importance, such as Nairobi Sheep Disease Virus (NSDV) which causes febrile illness in humans and lethal haemorrhagic gastroenteritis in goats and sheep with mortality rates of 90%. The aim of this study was to get insight into the genetic diversity of nairoviruses circulating in Uganda. Blood from cattle (n= 1064), goats (n= 1441), sheep (n=286), pigs (n=81), rodents and shrews (n=447) was collected in six areas in the Albertine rift valley in proximity to protected biodiversity hotspots and analysed using ultra-high-throughput sequencing and RT-PCR. NSDV was detected in 5 goats and 2 sheep from sampling sites across the rift valley, including Arua and Kasese Towns, as well as Semuliki and Bwindi Impenetrable National Parks. Complete NSDV genome analyses revealed nucleotide diversities of 0.5-25% to L, M and S segments of other NSDV strains. Further, two previously unknown nairoviruses were identified in rodents and shrews: one found in Bwindi Impenetrable National Park (n=3), and the others in Semuliki and Queen Elizabeth National Parks (n=5). The two novel viruses showed 85% pairwise nucleotide identities in their RdRp genes and maximal 65% pairwise identities to other rodent- and shrew-associated nairoviruses. These findings highlight the circulation of NSDV in goats and sheep and the presence of new nairoviruses in wildlife in Uganda, underscoring the need for an integrated One Health surveillance to prevent outbreaks.

Speaker: Mr Erick E. B. Kigai (Makerere University Kampala)

11:30 AM → 1:00 PM Session 12: Vectors

Conveners: Stefanie Becker, Sven Poppert

11:30 AM Simultaneous and Sequential Co-Infections with West Nile Virus and Usutu Virus in Culex pipiens biotype molestus

The epidemiological and geographical co-circulation of West Nile virus (WNV) and Usutu virus (USUV) poses the risk of potential co-infection in mosquito vectors. To investigate possible effects of co-infections in mosquitoes on the transmission of both viruses, a laboratory colony of Cx. pipiens biotype molestus was co-infected with WNV lineage 2 and USUV Europe 3, either simultaneously or sequentially in intervals of 7 days. Fourteen days after the last infection, infection and transmission were assessed.
After simultaneous co-infection, WNV transmission was increased compared to mono-infection, while USUV transmission was significantly reduced. In addition, WNV viral loads in mosquito bodies were significantly increased in mosquitoes with a concurrent USUV infection.
Similar effects on WNV loads were found in case of a WNV infection following a previous USUV infection; however, no significant impact on vector competence for USUV or WNV was observed. Initial experiments with a USUV infection after a previous WNV infection show a possible negative impact on USUV infection, indicating that WNV can outcompete USUV in any type of co-infection. Furthermore, possible negative effects of virus infection on mosquito fitness during sequential coinfection were observed, based on survival rates and biting behavior.
Further experiments will provide additional insights into the dynamics of WNV and USUV co-infections in mosquitoes, enabling risk assessment for regions with co-circulation.

Speaker: Christin Körsten (Friedrich-Löffler-Institut, Institute of Infectology)

11:45 AM A Multi-Ecosystem Analysis of the Links Between Land-Use Change, Mosquito Communities, and Virus Abundance

The emergence of mosquito-borne viruses is linked to land-use change and biodiversity loss, yet the ecological mechanisms driving these interactions remain poorly understood. This study aimed to identify common drivers for mosquito-borne virus emergence by studying the impact of land-use change on mosquito and virus community dynamics across lowland and montane rainforests and savannah.
A total of 32,632 mosquitoes, representing 130 species of 13 genera, were collected in disturbed and undisturbed sites. Mosquito species richness was significantly higher at undisturbed sites, with turnover rather than nestedness driving community differences across ecosystems. In total, we detected 665 viral sequences from 150 species, including 127 putative previously unknown viruses. Virus richness was higher at all undisturbed sites with more complex host-virus networks suggesting that land-use change homogenises mosquito-virus interactions, potentially altering transmission dynamics. Temperature was a key driver for mosquito abundance and diversity. Mosquito diversity correlated with virus diversity across ecosystems.
These findings highlight the role of vector communities in shaping viral communities. By using a multi-vector, multi-pathogen approach and integrating ecosystem-wide comparisons, this study advances our understanding of how anthropogenic disturbance influences vector-virus interactions and viral spread, with implications for public health and biodiversity conservation.

Speaker: Selina Graff

12:00 PM Studies on the co-localization of TBE-Virus and Borrelia species at selected TBEV-foci in Baden-Wuerttemberg

Ixodes ricinus is the main vector of several zoonotic pathogens in Central Europe, including Tick-Borne Encephalitis Virus (TBEV) and Borrelia burgdorferi sensu lato. Both are of major public health concern and call for integrated One Health surveillance. While co-circulation is known, co-localization in individual ticks remains largely unexplored.
In this study, 4587 ticks were collected in 2023–2024 from three confirmed TBEV microfoci and two TBEV-free sites in Baden-Wuerttemberg, Germany, and screened for both pathogens using molecular methods. TBEV-RNA was detected in 15 ticks and six of them (40%) were co-infected with different Borrelia species, mainly B. afzelii. Co-infections occurred in both nymphs and adult females.
Borrelia spp. prevalence across all sample sites ranged from 22% to 29%. The species detected were B. afzelii, B. garinii, B. valaisiana, B. burgdorferi s.s., B. lusitaniae and B. miyamotoi. Species composition was analyzed and compared between TBEV-endemic and TBEV-free sites.
These findings provide new evidence for the co-localization of human-pathogenic organisms in individual ticks. Co-infections may be more common than previously assumed and should therefore be considered both in diagnosis and in risk assessment.

Speaker: Ms Rebecca Vogt (University of Hohenheim, Department for Parasitology)

12:15 PM Plasticity in Thermal Tolerance, Vector Competence, and Metabolomic Responses of Culex pipiens under Seasonal and Microclimatic Variation

Due to global warming, vector-borne diseases are spreading worldwide. West Nile virus (WNV) outbreaks in Germany have increased since 2019, typically linked to hot summers. The main vector of WNV in Central Europe is the Culex pipiens species complex. While its role in transmission is well known, little is understood regarding how Culex pipiens responds physiologically and metabolically to heatwaves, raising questions about its climate resilience. We sampled six Culex pipiens populations along two urban-to-rural gradients in west and east Germany and across two seasons to assess survival and vector competence for WNV. To better understand their heat response, metabolomes of all populations were also analysed. Using random forest models, we evaluated the influence of biological factors (e.g. sex), climatic variables (micro- and macroclimate), and the experimental design (e.g. season) on heat survival and vector competence. Heat survival was affected by sex, age, season, and pre-oviposition microclimate, while vector competence was affected by season and especially the microclimate. Metabolomic profiling revealed differences between heat-treated and control individuals, as well as between populations, with the northernmost population possessing a distinct metabolic signature. These findings highlight the plasticity of thermal tolerance, metabolic response, and vector competence in Culex pipiens, with implications for WNV transmission under climate change.

Speaker: Isabelle Kramer (Goethe University Frankfurt)

12:30 PM Vectors on the rise – survivability of R. sanguineus s.l. in Germany

Changing temperatures and climate conditions led to expanding distribution areas and endemization of alien species in recent years. Rhipicephalus sanguineus s.l. is globally distributed and endemic in the Mediterranean region in Europe. Due to its close contact to dogs as hosts and its adaptation to dry and warm areas R. sanguineus s.l. is frequently introduced to Germany by vacationers with dogs and imported rescue dogs. These introductions led to infestations of homes including tick reproduction. Based on several reported autochthonous infestations, the question arose as to whether R. sanguineus s.l. survives in the field and possibly even form stable populations. Therefore, the ability of the two most frequently introduced species (R. sanguineus s.s. and R. linnaei) to survive under climatic conditions in Germany inside an experimental setup as close to nature as possible was investigated. For this purpose, the survivability of all developmental stages as well as of engorges females, the oviposition and the hatchability of egg masses was documented in weekly intervals from February 2023 to May 2024. R. sanguineus s.s. exhibited longer average survival time than R. linnaei at all developmental stages, whereas R. sanguineus s.s. survived outdoors for up to 44 weeks. Engorged females of both species successfully laid eggs from which viable larvae hatched. However, no stage of either species was able to survive the winter period (Nov. to Feb.) for more than 2–4 weeks.

Speaker: Katrin Fachet-Lehmann (University of Hohenheim, Parasitology)

12:45 PM Vector Behavior meets Transcriptomics: A Case Study of Ixodes ricinus and Harz Mountain Virus

Ticks are important vectors of emerging viruses, including the Jingmenvirus Alongshan virus strain Harz Mountain (ALSV_HM), recently identified in Ixodes ricinus ticks collected from game animals in Lower Saxony, Germany. To investigate the transcriptomic impact of ALSV_HM, adult I. ricinus were experimentally infected via intrathoracic injection and incubated for seven days. Subsequently, RNA sequencing was performed, and reads were aligned to the Ixodes scapularis genome. Infected ticks showed significant upregulation of gene transcripts related to immune response, intracellular signaling, and RNA/DNA-binding functions, suggesting a broad activation of antiviral pathways and transcriptional regulation. Transcripts encoding transport- and membrane proteins were downregulated, implying potential disruption of cellular homeostasis and molecular transport. Interestingly, transcripts associated with aggressive behavior in other arthropods were also differentially expressed. To test behavioral changes, vertical and horizontal repellency assays using Icaridin were used. ALSV_HM-infected ticks displayed reduced sensitivity to Icaridin during vertical questing, whereas horizontal movement remained unaffected. These findings suggest that ALSV_HM alters both gene expression and host-seeking behavior in I. ricinus, potentially enhancing transmission dynamics and underscoring the need for surveillance of novel tick-borne viruses in a changing environment.

Speaker: Paula Hornauer (Stiftung Tierärztliche Hochschule Hannover)

1:00 PM → 2:00 PM Lunch

2:00 PM → 2:30 PM Keynote VI: Joseph Prescott: BBats as reservoirs of viral zoonoses: How Egyptian fruit bats combat Marburg virus infection

Conveners: Kevin Ciminski, Lisa Oestereich

2:30 PM → 3:30 PM Poster Prize & Farewell

Conveners: Fabian Leendertz (HIOH Greifswald), Sascha Knauf (Friedrich-Loeffler-Institut)