CD4 and COVID-19: Notably, as evident from Table 11, the IgG COVID-19 positive trial group candidates showed more reduced (mean difference BT-AT, p-value) lymphocyte subsets CD3+ (640, p = 0.00), CD4+ (315.14, p = 0.00), and CD8+ (265.14, p = 0.00) levels than antibody negative candidates in trial group (CD3+ 190.61; p = 0.01, CD4+ 64.65; p = 0.08, CD8+ 99.97; p = 0.02).