Sustained responses to measles revaccination among Kenyan HIV-infected children on antiretroviral therapy
HIV-infected children have reduced rates of measles antibody production and immunologic memory after measles vaccination in the absence of antiretroviral therapy (ART). In this study, Kenyan HIV-infected children 15 months to 12 years of age on ART received an additional measles vaccine. Measles antibody concentrations were determined by enzyme-linked immunosorbent assay (ELISA) at enrollment, one month, and 12 months post revaccination. At enrollment, 125 (54%) of 232 study participants had protective levels of measles antibody. Seropositivity increased to 98% at one month post revaccination and 70% at 12 months post revaccination. Seroconversion and sustained seropositivity among those who were seronegative at enrollment was 37% at 12 months post revaccination. Low HIV viral load and increased height-for-age z-score were associated with sustained measles vaccination responses. Measles revaccination conferred a sustained antibody response in HIV-infected children receiving ART, especially those who had suppressed levels of HIV virus.