Humoral and cellular immune response levels at a 1-year follow-up after mild COVID-19.

The primary objective of this study was to establish a 1-year follow-up of patients after mild COVID-19 with no or only short-term detection of antibodies shortly after disease. At 1 year after disease, cellular memory against SARS-CoV-2, as measured by IFN-γ release by T cells, was detected in 76% (38/50) of participants. The data suggest that even if antibody levels decline after the primary infection has resolved, a cellular immune response may be detectable for longer.