STOPPING TRANSMISSION

Our goal is to interrupt leprosy transmission in the countries in which we work by 2030. To achieve this we are researching, developing, and implementing evidence-based tools to interrupt the transmission of leprosy, especially early diagnostic tests and post-exposure prophylaxis.

Improving preventative regimens through PEP++

TLM is partnering with NLR in the PEP++ study, which is taking place in Bangladesh, Brazil, India and Nepal. The COLEP study (Moet et al, 2008) demonstrated that a single dose of rifampicin given to contacts of leprosy patients reduces the chance of developing leprosy by about 60%. The PEP++ regimen of rifampicin plus clarithromycin seeks to reduce this to 80–90%. The study has two parts: PEP++ for close contacts, and a blanket SDR-PEP study. In Bangladesh, TLM has enrolled more than 50,000 people in each part of the study. Follow up of the close-contact study will continue until mid-2026 and will include testing for antimicrobial resistance in all new cases detected.

Monitoring the transmission of leprosy among children

We know that leprosy in children is a clear indication of recent transmission of M. leprae. In Bangladesh, the Child Serosurvey Study seeks to find out how many children have been exposed to M.leprae—even if they don't have symptoms yet. We have enrolled almost 6,000 children (aged between five and 10 years) in three districts in North-West Bangladesh. The team at Leiden University Medical Centre are supporting us to analyse the samples. The findings of will help identify areas where transmission of leprosy is still happening, and will inform decisions for more prevention activities.

A new, point-of-care diagnostic test for leprosy

Truenat is a chip-based, point of care, rapid molecular test for diagnosis of infectious diseases, and is already used by TB programmes in many countries, including India. The Leprosy Mission Trust India (TLMTI) has developed a multiplex PCR (mPCR) test for M. leprae using Truenat that is 100% accurate for MB leprosy and 88% accurate for PB leprosy.

STOPPING TRANSMISSION

Improving training for healthcare workers

In 2021, ILEP concluded that knowledge gaps exist at all levels of leprosy programmes and approaches used to train people were outdated and not sustainable. With that in mind, the LRI-funded Capacity Building in Leprosy project (CapaBLe) aims to study the effect of updated, modernised training materials developed for those working with people affected by leprosy in India and Nigeria. The training packages are being defined based on the needs of the target group in the two countries in close collaboration with the Ministries of Health. The results will be useful for improving training, to convince others to use the trainings in other countries, and to add more evidence to what we already know about certain training approaches.

Developing a new treatment for leprosy

The Leprosy Mission Trust India are conducting an open-label randomised clinical control non-inferiority trial of WHO-MDT versus rifampicin, moxifloxacin and clarithromycin for MB leprosy (RMC trial). The intervention group receive a monthly supervised regimen of rifampicin, moxifloxacin and clarithromycin which will be administered in doses of 600 mg, 400 mg, and 1000 mg respectively once a month. The control arm receives routine WHO MB MDT (rifampicin 600 mg, clofazimine 300 mg once monthly and clofazimine 50 and dapsone 100 mg daily). The duration of the treatment in both arms is 12 months. Participants in the study will undergo various assessments, including qPCR, clinical examination (skin and nerves) and Bacillary Index (BI). These assessments will occur at the start of the study and after 3, 6 and 12 months.

STOPPING TRANSMISSION

Understanding the role of B-cells and antibodies in leprosy

Current diagnostic tools for diagnosing leprosy aren't good enough—especially for use in remote or low-resource settings. Most diagnoses today still rely on visible symptoms, which appear only after the disease has progressed.

The '2B-or-not-2B' Study focuses on a specific part of the immune system: B-cells and the antibodies they produce. In many infections, antibodies help the body fight off disease. But in leprosy, people with the most severe form of the disease actually have high levels of antibodies against M. leprae, suggesting these antibodies might not protect the body in the usual way. The role of these antibodies—and the B-cells that make them—is still unclear.

TLM researchers in Nepal and Bangladesh are working with Professor Annemieke Geluk and her team at the Leiden University Medical Center to better understand how B-cells and antibodies behave in leprosy. They are studying blood and skin samples from leprosy patients, their close contacts, and people with other skin conditions.

The goal is to translate these findings into practical diagnostic tests. They will be simple, fast, and easy to use in the field—using just a small finger-prick of blood. For example, if certain types of antibodies or immune cell markers are found only in people with early leprosy, these could be detected using a rapid test—similar to a COVID-19 or pregnancy test.

These new diagnostics could help identify people who are infected before symptoms appear, making it easier to treat them early and prevent further transmission