Extensively drug-resistant tuberculosis hotspots and sociodemographic associations in Durban, South Africa

Abstract

BACKGROUND : Extensively drug-resistant tuberculosis (XDR-TB) incidence is driven by transmission of resistant strains in KwaZulu-Natal, South Africa. Data suggests cases may be spatially clustered; we therefore sought to identify hotspots and describe these communities. METHODS : We enrolled XDR-TB patients diagnosed from 2011–2014 in eThekwini. GPS coordinates for participant homes were collected and hotspots were identified based on population-adjusted XDR-TB incidence. Sociodemographic features of hotspots were characterized using census data. For a subset of participants, we mapped XDR-TB case non-home congregate locations and compared to results including only homes. RESULTS : Among 132 participants, 75 (57%) were female and 87 (66%) lived in urban or suburban locations. Fifteen of 197 census tracts were identified as XDR-TB hotspots with ≥ 95% confidence. Four spatial mapping methods identified one large hotspot in northeastern eThekwini. Hotspot communities had higher percentages of low educational attainment (12% vs 9%), higher unemployment (29.3% vs 20.4%), and lower percentage of homes with flush toilets (36.4% vs 68.9%). Mapping congregate locations, including workplaces, for 43 (33%) participants shifted case density towards Durban. CONCLUSIONS : In eThekwini, XDR-TB case homes were clustered into hotspots with more indicators of poverty than non-hotspots. Prevention efforts targeting hotspot communities and congregate settings may be effective in reducing community transmission.