Environmental reservoirs of Mycobacterium bovis and Mycobacterium tuberculosis in the Ruaha region, Tanzania

This study was designed to investigate the prevalence of members of the Mycobacterium tuberculosis complex (MTBC) in the environment of pastoralists and villagers in the Iringa district, adjacent to the Ruaha National Park in Tanzania. Utilising specific qPCR assays, both Mycobacterium bovis and Mycobacterium tuberculosis were detected in cattle faeces, boma soil, water and household dust. M. bovis was also found in goat faeces and goat boma soil. This is the first report of faecal shedding of M. bovis in goats and the first molecular survey of faecal shedding in cattle. The prevalence of both bacterial species varied by village, area, season and sample type. Geographical and temporal correlations across sample types were suggestive of cross species transmission. This non-invasive test has previously been rigorously validated for screening other mammals; in this study it has successfully been applied to detect M. bovis and M. tuberculosis in livestock faeces and the environment.