CD4 and COVID-19: Specifically, PLWH not on antiretroviral therapy, with detectable viral loads and low CD4+ T cell counts (<200 cells/mm3) and/or with low CD4+ T cell count nadir, showed a higher risk of developing an anomalous immune response—characterized by delayed or insufficient antibody production after SARS-CoV-2 infection, as well as a greater risk of severe COVID-19 [20,21,22,23].