Durability of Functional SARS-CoV-2-Specific Immunological Memory and T Cell Response up to 8-9 Months Postrecovery From COVID-19.

Research on long-term follow-up in individuals who have recovered from coronavirus disease-19 (COVID-19) would yield insights regarding their immunity status and identify those who need booster vaccinations. This study evaluated the longevity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific cellular and humoral memory responses, as well as T cell effector functionalities, at 1-2 months ( = 40), 8-9 months ( = 40), and 12 months/1 year ( = 27) following recovery from SARS-CoV-2 infection. CTL response by enzyme-linked immunospot (ELISPOT); levels of cytokine by Bio-Plex, natural killer (NK), CD4+ helper, and CD8+ cytotoxic T cell functionalities using flow cytometry; anti-SARS-CoV-2 IgG by ELISA; and levels of neutralizing antibodies (NAbs) by surrogate virus NAb assay were assessed.