Vaccination resulted in seroconversion and neutralizing antibody responses in PLWH on ART who were virally suppressed with good CD4+ T cell counts. Neutralizing antibody and anti-S antibody titres were like those displayed by healthy controls, even when stratified according to the CD4+ T cell countPLWH with prior SARS-CoV-2 infection displayed higher anti-S antibody titres (P = 0.0007) and neutralizing antibody activity in sera (P = 0.0007) than COVID-19-naïve PLWH. Here, CD4 is linked to COVID-19.