Community-level variation in TB testing history: analysis of a prevalence survey in Blantyre, Malawi

Equitable access to tuberculosis testing is vital for achieving global treatment targets, but access to diagnostic services is often worse in poorer communities. The SCALE survey to estimate TB prevalence in Blantyre city, Malawi, also recorded engagement with TB services. We explored variation in self-reported TB testing history between 72 community clusters - adjusting for sex, age and HIV status - and investigated whether residual differences could be explained by household poverty. We observed substantial variation between clusters in the prevalence of ever-testing for TB, with little correlation between neighbouring clusters. Participants in poorer households had, on average, lower odds of ever-testing, yet adjusting for poverty did not reduce cluster-level variation. We conclude that, despite a decade of increased active case finding efforts, access to TB testing is inconsistent across the population of Blantyre, likely reflecting health inequities that also apply to TB testing in many other settings.