CD4 and COVID-19: Previous research has demonstrated increased antigen-specific T-cell responses and decreased functionality in those with moderate-to-severe acute COVID-19 as early as 1-month postsymptom onset.60,61 When stimulated with either SARS-CoV-2 peptide pool, 2 (4.9%) and 4 (20%) of the COVID and HIV + COVID groups, respectively, had a CD4+ T-cell AIM response.