Community-level variation in TB testing history in Blantyre, Malawi

SETTING: Equitable access to TB testing is vital for achieving global diagnosis and treatment targets, but access to diagnostic services is often worse in poorer communities. The SCALE (Sustainable Community-wide Active case-finding for Lung hEalth) survey estimated TB prevalence in Blantyre City, Malawi, and recorded previous engagement with TB services.OBJECTIVE: To explore local variation in the prevalence of ever-testing for TB in Blantyre and investigate potential socio-economic drivers.DESIGN: We fit a mixed-effects model to self-reported prior TB testing from survey participants across 72 neighbourhood clusters, adjusted for sex, age and HIV status and with cluster-level random intercepts. We then evaluated to what extent cluster-level variation was explained by two alternate poverty indicators.RESULTS: We observed substantial variation between clusters in previous TB testing, with little correlation between neighbouring clusters. Individuals residing in less affluent households, on average, had lower odds of having undergone prior testing. However, adjusting for poverty did not explain the cluster-level variations observed.CONCLUSION: Despite a decade of increased active case-finding efforts, access to TB testing is inconsistent across the population of Blantyre. This likely reflects health inequities that also apply to TB testing in many other settings, and motivates collection and analysis of TB testing data to identify the drivers behind these inequities.