The association of ethnicity with antibody responses to pneumococcal vaccination among adults with HIV infection.

Ethnicity may be associated with the incidence of pneumococcal infections and the frequency of protective vaccine responses. Earlier studies have suggested that HIV-infected persons of black ethnicity develop less robust immune responses to pneumococcal vaccination that may relate to their higher incidence of invasive disease. We evaluated the association of ethnicity with capsule-specific antibody responses to pneumococcal revaccination, with either the pneumococcal conjugate (PCV) or polysaccharide (PPV) vaccines among 188 HIV-infected adults. The proportion of the 77 African Americans (AA) and 111 Caucasians with comparable virologic and immunologic parameters who achieved a positive immune response (≥2-fold rise in capsule-specific IgG from baseline with post-vaccination value ≥1 μg/mL for ≥2 of 4 serotypes) at day 60 after revaccination was similar (43% vs. 49%, respectively, p=0.65). Results were also similar when vaccine types (PPV and PCV) were examined separately. Mean changes in log(10) transformed IgG levels from baseline to days 60 and 180 post-vaccination were also not significantly different between AA and Caucasians. In summary, in this ethnically diverse cohort with equal access to care, we did not observe differential antibody responses between AA and Caucasian HIV-infected adults after pneumococcal revaccination.