The latest on this exciting research in Bangladesh
The Leprosy Mission’s team in Bangladesh are working on a research project that could dramatically reduce the rate of leprosy transmission within communities and prevent people from developing leprosy-related disabilities because of late treatment. By developing a new field-friendly diagnostic tool and testing preventative medicines, the team are hoping to take big strides towards our goal of zero leprosy.
This image and cover image: © Tom Bradley
Did you know that a person with leprosy can be asymptomatic, and that we have no lab test that can confirm whether they have leprosy or not?
Researchers estimate that there are “missing millions” of asymptomatic or undiagnosed leprosy cases, and that these untreated cases are the reason leprosy transmission continues to stably persist in populations.
Currently, only those with detectable symptoms can be conclusively diagnosed with leprosy and treated; and signs and symptoms are often delayed 2-5 years and up to 30 years. Late diagnosis can also lead to nerve damage and disability.
In order to impact transmission, we need a reliable diagnostic test that is capable of detecting asymptomatic and early leprosy cases. This is a key priority for TLM research.
At the moment, a household contact or close neighbour of a newly diagnosed person won’t be tested for leprosy because there is no effective diagnosis tool. They could have contracted the disease and be infectious, but no one will be able to tell because they don’t have any symptoms yet.
In partnership with Dr Annemieke Geluk and her team at Leiden University Medical Center, TLM Bangladesh is performing field trials of a finger-prick test, much like the one used to diagnose diabetes. The aim is to test 10 household or neighbouring contacts from 100 leprosy cases. This means, if you are diagnosed with leprosy, 10 of your household contacts and neighbours will receive a finger-prick blood test.
They will be initially tested four times over a period of six months to track crucial biomarkers. After six months, the contacts will be followed up annually over the next few years to see if any do develop leprosy symptoms or not. In this way, they can correlate which finger-prick results indicated asymptomatic or early leprosy.
Dr Annemieke Geluk and her team have been developing leprosy diagnostics over many years, across continents and countries – including both TLM Bangladesh and Nepal. But this is the first study that will simultaneously test for six different biomarkers in the blood.
Our researchers hope that it could prove an effective way to diagnose leprosy in a person and give them treatment long before they develop leprosy-related complications. Further to this, these tests could significantly impact and reduce the numbers of hidden cases of leprosy and persistent transmission, helping to bring about the eventual defeat of this horrible disease.
© Tom Bradley
The biomarkers that the team are testing show whether or not a person has asymptomatic leprosy; so, while they are testing for these biomarkers, they are also testing different forms of PEP (Post-Exposure Prophylaxis) treatment to see which is better at preventing a leprosy development in contacts.
PEP is a prophylaxis, or a treatment that reduces the risk of a person developing leprosy. With PEP, a person who is a close contact of a recently diagnosed person is given a dose of Rifampicin, one of the antibiotics used to treat leprosy.
In a previous TLM Bangladesh study, run in partnership with Dr Jan Hendrik Richards and Erasmus University, a single dose of Rifampicin as PEP was seen to reduce the risk of developing leprosy by an average of 57 percent; however, protection was highest for furthest away neighbours and lowest for household family.
In the current study, our team are looking at whether two doses of Rifampicin is more effective by tracking these crucial biomarkers for indications of growing leprosy infections after PEP treatment.
This research could push us towards zero leprosy
The new finger-prick test could go a long way to identifying leprosy patients earlier than ever before. As well as this, knowing the right dose of Rifampicin to give to a potential patient is crucial in our efforts to stop the disease spreading further. The discoveries we might make through this research could enable us to achieve our goal of zero leprosy transmission by 2035.
