Project coordination
NLR, the Netherlands

Partners
Erasmus University Medical Center Rotterdam (Erasmus MC), the Netherlands
DAHW Deutsche Lepra- und Tuberkulosehilfe e. V., Germany
Ministry of Health, Community Development, Gender, Elderly and Children - Tanzania, United Republic of Tanzania
Catholic University of Health and Allied Sciences-Bugando (CUHAS), United Republic of Tanzania
Ministerio da Saúde – Mozambique, Mozambique
Universidade Lúrio, Mozambique
Federal Democratic Republic of Ethiopia Ministry of Health (FMOH), Ethiopia
Armauer Hansen Research Institute (AHRI), Ethiopia

Aim: The aim of the PEP4LEP study was to contribute to interrupting the transmission of M. leprae by identifying the most effective and feasible method of screening people at risk of developing leprosy and administering chemoprophylaxis in Ethiopia, Mozambique and Tanzania.

Full project title:
PEP4LEP: Chemoprophylaxis for leprosy: comparing the effectiveness and feasibility of a skin camp intervention to a health centre based intervention. An implementation trial in Mozambique, Ethiopia and Tanzania.

Final project summary:
A single dose of rifampicin (SDR) can reduce the risk of developing leprosy by nearly 60% when given to people who have been in contact with a person affected by the disease. Although the World Health Organization (WHO) recommends this form of post-exposure prophylaxis (PEP), there is limited evidence on the most effective and practical way to deliver it in routine health services.

The PEP4LEP project was established to compare two approaches to leprosy screening and SDR-PEP delivery in Mozambique, Ethiopia, and Tanzania. The first approach used community skin camps, while the second relied on household contact screening through health centres. To reduce stigma and increase the broader health benefits of screening, participants were not only examined for leprosy but also for other skin diseases. Eligible contacts received SDR-PEP following screening.

The study compared the two approaches by assessing case detection rates, delays in diagnosis, cost-effectiveness, and acceptability among health workers, participants, and other stakeholders. Both interventions also incorporated the NLR SkinApp, a mobile health tool developed to support health workers in conducting skin examinations in settings where access to dermatological expertise is limited.

The project included approximately 30,000 contacts of people affected by leprosy and generate evidence to inform future national and international guidelines on leprosy screening and prevention.

During the study period, data collection continued across all three countries, alongside ongoing data quality assurance activities. Additional work was conducted to support the cost-effectiveness and acceptability components of the study, including literature reviews, questionnaire development, adaptation and translation of study tools, and the transcription and translation of interviews. Two doctoral candidates successfully completed their dissertations based on the project, while a third planned to do so in 2025. Preliminary findings were presented at scientific meetings and conferences, and several peer-reviewed articles were published.

Project implementation was affected by global rifampicin shortages linked to the COVID-19 pandemic. However, once medication supplies became available again, all participating countries were able to resume recruitment and project activities.

A total of 177 index patients were enrolled in the community skin camp intervention and 3,375 index patients in the health centre-based intervention. In the community skin camp approach, 18,632 contacts were screened, resulting in the identification of 240 newly diagnosed leprosy patients. In addition, 9,080 participants (48.7%) were found to have one or more skin conditions. In the health centre-based screening approach, 1,269 contacts were examined, of whom 28 were diagnosed with leprosy, while 146 individuals (11.5%) were identified as having at least one skin condition.

The project findings have been shared nationally and internationally, and draft guidelines on leprosy screening and prevention have been developed. Study materials and publications have been made openly available to healthcare workers, researchers, and policymakers. A further outcome of the project was the integration of the NLR SkinApp into the WHO Skin NTD App, incorporating updates generated through the PEP4LEP study.

The project consortium also secured support to continue data collection beyond the original study period through a follow-on initiative, PEP4LEP 2.0, funded under the Global Health EDCTP3 programme. This continuation was established to enable the completion of research activities that had been affected by disruptions during the COVID-19 pandemic.

Overall, the PEP4LEP project has generated important evidence on different approaches to contact screening and SDR-PEP delivery while also strengthening the integration of skin disease screening into leprosy control activities. The findings are expected to contribute to future policy and programme development for leprosy prevention and early case detection.

Impact

Hambridge, T., Coffeng, L. E., De Vlas, S. J., & Richardus, J. H. (2023). Establishing a standard method for analysing case detection delay in leprosy using a Bayesian modelling approach. Infectious diseases of poverty, 12(01), 71-81.

Mwageni, N., van Wijk, R., Daba, F., Mamo, E., Debelo, K., Jansen, B., ... & Mshana, S. E. (2024). The NLR SkinApp: Testing a supporting mHealth tool for frontline health workers performing skin screening in Ethiopia and Tanzania. Tropical Medicine and Infectious Disease, 9(1), 18.

Mamo, E., van Wijk, R., Schoenmakers, A., Bobosha, K., Legesse, M., Hambridge, T., ... & Mieras, L. (2024). Case detection delay in leprosy: Testing tool reliability and measurement consistency in Ethiopia, Mozambique, and Tanzania. PLoS neglected tropical diseases, 18(7), e0012314.

Main funder

European & Developing Countries Clinical Trials Partnership

Supported by the European Union