Project coordination
Institute of Tropical Medicine (ITG), Belgium

Aim: This “cluster randomized” trial on effectiveness of different modalities of Single Double Dose of Rifampicin Post-Exposure Prophylaxis (SDDR-PEP) for leprosy in the Comoros (Anjouan and Mohéli) and Madagascar. 

Full project title:
PEOPLE: Post ExpOsure Prophylaxis for LEprosy in the Comoros and Madagascar

Final project summary:
Leprosy remains a public health challenge in several endemic countries, and new approaches are needed to reduce transmission and prevent new cases. One promising strategy is post-exposure prophylaxis (PEP), in which contacts of people affected by leprosy receive preventive treatment. The PEOPLE project evaluated different approaches to delivering PEP in highly endemic communities in the Comoros and Madagascar.

The study compared four approaches. One group received the standard approach without PEP, while three intervention groups received a single double dose of rifampicin (SDDR): household contacts only; all contacts living within a 100-metre radius of an identified case; or household contacts plus individuals living within a 100-metre radius who tested positive for anti-PGL-I antibodies. Annual door-to-door screening was conducted and eligible participants received preventive treatment.

Between 2019 and 2023, the study registered a total population of more than 110,000 people across participating villages in the Comoros and Madagascar. Nearly 87% of registered individuals were examined at least once during follow-up, and almost 20,000 people received preventive treatment. Despite disruptions caused by the COVID-19 pandemic, all planned screening rounds were completed.

The study showed that PEP provided protection against leprosy at both the individual and community levels. The findings also demonstrated a strong relationship between geographical proximity to a person affected by leprosy and the risk of developing the disease. The results suggest that the greatest impact on transmission may be achieved through systematic screening of household contacts and people living in close proximity to diagnosed patients, combined with the provision of preventive treatment.

Alongside the intervention trial, researchers explored community perceptions and acceptability of the programme in the Comoros and Madagascar. Overall, the intervention was well accepted, although some challenges were identified, including limited awareness of early leprosy symptoms and concerns related to blood sampling. The study also highlighted the importance of migration and social networks in understanding how leprosy spreads within and between communities.

A molecular component of the project investigated patterns of transmission and monitored antibiotic resistance. Using a newly validated sequencing method, researchers found no evidence of resistance to rifampicin, fluoroquinolones, or dapsone among the samples tested. Genetic analyses also provided new insights into the diversity and distribution of Mycobacterium leprae strains in the study areas.

The project generated a range of scientific outputs and contributed to strengthening local research and clinical capacity. Large field teams were trained in leprosy diagnosis and surveillance, while new tools and methods for epidemiological mapping, data collection, and molecular testing were introduced and strengthened.

Overall, the PEOPLE project provides important evidence on the use of post-exposure prophylaxis as a tool for leprosy prevention. The findings support the value of targeted contact screening and preventive treatment and contribute to ongoing efforts to reduce transmission and improve leprosy control in endemic settings.

Impact

Hasker, E., Assoumani, Y., Randrianantoandro, A., Ramboarina, S., Braet, S. M., Cauchoix, B., ... & de Jong, B. C. (2024). Post-exposure prophylaxis in leprosy (PEOPLE): a cluster randomised trial. The Lancet global health, 12(6), e1017-e1026.

Main funder

European & Developing Countries Clinical Trials Partnership

Supported by the European Union