Transient lymphocytopenia is frequently observed in acute phase of coronavirus disease 2019 (COVID‐19). It remains a concern whether impairment of cellular immunity may be retained after COVID‐19. Here, we demonstrate by extensive lymphocyte profiling in 44 adults after mild COVID‐19 that cellular immunity is not fundamentally altered in convalescent patients. Except for increased activated CD8+ lymphocytes, total counts of B, T, and NK cells and their subsets did not differ significantly between patients after COVID‐19 and healthy controls after a median of 27 days (range 13–45) suggesting no residual cellular immune deficiency after recovery from mild COVID‐19.
Sustained cellular immunity in adults recovered from mild COVID‐19