Objective: Adults living with HIV (ALWHIV) on antiretroviral therapy (ART) are at high risk of pneumococcal carriage and disease. To help evaluate carriage risk in African ALWHIV at least 4-years after infant pneumococcal conjugate vaccination introduction in 2011, we assessed association between pneumococcal carriage and potential risk factors.
Methods: Nasopharyngeal swabs were collected from adults aged 18-40 years attending an ART clinic during rolling, cross-sectional surveys in Blantyre, Malawi between 2015-2019. We fitted generalised additive models to estimate the risk of sex, social economic status (SES), living with a child <5y, and ART duration on carriage.
Results: Of 2,067 adults, median age was 33y (range 28-37), 1,427 (69.0%) were females, 1,087 (61.4%) were in low-middle socio-economic-status (SES), 910 (44.0%) were living with a child <5y, and median ART duration was 3.0 years (range 0.004-17). We estimated 38.2% and 60.6% reductions in overall and vaccine-serotype carriage prevalence. Overall carriage was associated with low SES, living with a child <5y and shorter duration on ART. By contrast, vaccine-type carriage was associated with living without a child <5y and male sex.
Conclusion: Despite temporal reductions in overall and vaccine-serotype carriage, there is evidence of incomplete vaccine-serotype indirect protection. A targeted-vaccination campaign should be considered for ALWHIV, along with other public health measures to further reduce vaccine-serotype carriage and therefore disease.
Thindwa D, Mwalukomo TS, Msefula J, Jambo KC, Brown C, Kamng’ona A, Mwansambo C, Ojal J, Flasche S, French N, Heyderman RS, Swarthout TD.