Prior studies have not been consistent in indicating an increased risk of breakthrough infection in people with HIV (PWH), an immunocompromised population, vs people without HIV (PWoH); these studies were limited in geographic scope, number of PWH, and did not consider HIV viremia or CD4 T-lymphocyte count.10,11,12 Vaccine clinical trials were insufficiently powered to stratify outcomes by HIV status.1,2,3. This evidence concerns the gene CD4 and infection.