Exploring HIV infection and susceptibility to measles among older children and adults in Malawi: a facility-based study

Abstract

Background HIV infection increases measles susceptibility in infants, but little is known about this relationship among older children and adults. We conducted a facility-based study to explore whether HIV status and/or CD4 count were associated with either measles seroprotection and/or measles antibody concentration. Methods We conveniently sampled HIV-infected patients presenting for follow-up care, and HIV-uninfected individuals presenting for HIV testing at Chiradzulu District Hospital, Malawi, from January to September 2012. We recorded age, sex and reported measles vaccination and infection history. Blood samples were taken to determine CD4 count and measles antibody concentration. Results 1935 (1434 HIV-infected; 501 HIV-uninfected) participants were recruited. The majority of adults, and approximately half the children, were measles seroprotected, with lower odds among HIV-infected children (adjusted OR=0.27, 95% CI: 0.10-0.69, p=0.006), but not adults. Among HIV-infected participants, neither CD4 count (p=0.16) nor time on antiretroviral therapy (p=0.25) were associated with measles antibody concentration, while older age (p<0.001) and female sex (p<0.001) were independently associated with this measure. Conclusions We found no evidence that HIV infection contributes to the risk for measles infection among adults, but HIV-infected children (including at ages older than previously reported), were less likely to be seroprotected in this sample.