Tuberculosis among transhumant pastoralist and settled communities of south-eastern Mauritania

BACKGROUND: Transhumant pastoralists of Mauritania were assumed to have a high prevalence of tuberculosis (TB) because of reduced access to diagnostic testing. No population-based survey on TB has been published for Mauritania.
OBJECTIVE: The goal of this study was to estimate the prevalence of presumptive TB cases among mobile pastoralists and villagers in a remote zone of Mauritania.
DESIGN: In the south-eastern province of Hodh Ech Chargui, 250 adult pastoralists and 250 villagers were randomly enrolled using multistage cluster sampling in February 2012. A TB centre nurse examined participants using a standard clinical protocol, and a participant questionnaire was completed. Focus group discussions and interviews were conducted with community members and health personnel, respectively.
RESULTS: Fourteen new presumptive TB cases were identified, leading to an overall prevalence of 2.8%, (95% confidence interval (CI) 1.5-4.7%). The prevalence was non-significantly higher among villagers than pastoralists (3.6% vs. 2.0%). Assuming illness duration was 3 years and all presumptive cases started treatment, an overall crude incidence of 933 cases/100,000 was derived. Five of six presumptive cases in Djiguenni were confirmed by sputum smear microscopy, but none out of eight presumptive cases were confirmed in Néma, although the same nurse performed all clinical examinations in both departments. This result was attributed to the use of expired reagents in Néma. Communities mentioned distance rather than lack of information as the main constraint to seeking diagnosis, but poor diagnostic centre performance also delayed decision-making.
CONCLUSIONS: TB prevalences were high among both pastoralists and villagers. None of the 14 presumptive cases sought prior diagnostic testing. TB diagnostic centres in the remote rural study zone were poorly equipped. These centres must remain in operation to reduce TB incidence in vulnerable communities in insecure remote rural zones and to reach national health goals.