CD4 and COVID-19: In the COVID-19(+) patients we noticed the lowest median proportion of CD25+ CD4+, and CD8+ CD25+ cells compared to the HC group and COVID-19(−) virus group (respectively for CD4+ CD25+: 3.0 vs. 19.8 vs. 24.1, for CD8+ CD25+: 0.2 vs. 2.5 vs. 3.4, p < 0.05) (Figure 1, Table 4).