Contribution of drug-resistance and M. lepromatosis to persistent leprosy transmission in parts of Africa

In this cross-sectional observational study, we will test whether drug resistance and M. lepromatosis infections contribute to transmission of leprosy in four African countries. Out of the six African countries that have already conducted drug resistance screenings, only the Comoros and Ethiopia did not detect any resistance, albeit on few samples tested in Ethiopia. Therefore, we propose to recruit leprosy patients in the national leprosy control programs of Ghana, Burundi, Cameroon and the Democratic Republic of Congo. In collaboration with the implementers of the Biomeme platform we will screen biopsies from leprosy patients for the presence of the RLEP insertion sequence, specific for M. leprae. Positive DNA extracts will be tested for resistance mutations beyond the three known targets (folp1, gyrA, rpoB) by Hain LPA testing and all extracts (both positive and negative) for the presence of M. lepromatosis. External Quality Assurance (EQA) will be provided by Prof Cambau (INSERM, Paris), integrated with EQA for other skin NTDs such as M. ulcerans, prepared by the BU Labnet. Furthermore, by genotyping (by targeted- or whole genome sequencing) M. leprae in the samples of patients, we will test whether genotypic clustering of M. leprae is suggestive of recent transmission within the country and we will investigate if any other gene target is possibly related to drug resistance. As the endemic countries differ regarding available molecular platforms and expertise, capacity building will be adapted, with south-south exchanges and collaboration with BU Labnet encouraged. Bioinformatics analyses will be conducted jointly to enhance capacity.