Description
Since 2013, influenza A/H7N9 has emerged as the commonest avian influenza subtype causing human infection, and is associated with a high fatality risk. However, the characteristics of immune memory in patients who have recovered from H7N9 infection are not well understood. We assembled a cohort of forty-five H7N9 survivors and followed for up to 15 months after infection. Humoral and cellular immune responses were analyzed in sequential samples obtained at 1.5-4 months, 6-8 months and 12-15 months post-infection. H7N9-specific antibody concentrations declined over time while frequencies of virus-specific IFN-γ, IL-2 or TNF-α secreting T cells were higher at 12-15 months post infection than at earlier time points. Elevated levels of antigen-specific CD8+ T cells expressing lung-homing marker CD49a were observed at 6-8 months after H7N9 infection compared to samples obtained at 1.5-4 months. Our findings indicate the prolonged reconstruction and evolution of virus-specific T cell immunity, and provide implications for T-cell directed immunization strategies.
| Choose primary session | Vaccines and antivirals |
|---|---|
| Choose secondary Session | Pathogenesis |
