Where is leprosy found?
Historically, leprosy was found worldwide; today it is mainly found in 14 countries: Bangladesh, Brazil, DR Congo, Ethiopia, India, Indonesia, Madagascar, Mozambique, Myanmar, Nepal, Nigeria, Philipppines, Sri Lanka and Tanzania. More than half of all leprosy cases are diagnosed in India.
How is leprosy spread?
Leprosy is only mildly infectious. How a person acquires Mycobacterium leprae and develops the disease remains uncertain, although it is currently thought likely that it is spread when healthy individuals inhale water droplets coughed or sneezed by infected people. Prolonged, close contact with someone suffering from leprosy is needed to catch the disease, and more than 95% of people have natural immunity to the disease.
Currently, leprosy has to be diagnosed using clinical symptoms as there is no diagnostic laboratory screening test.
Is leprosy curable?
Leprosy is curable with antibiotic treatment for 6-12 months. Unfortunately, for many people living in poverty around the world, diagnosis is too late to avoid limb damage or blindness, and the stigma associated with these injuries and a leprosy diagnosis.
Vaccines against leprosy
There is currently no vaccine specifically for leprosy. BCG was developed as a vaccine against tuberculosis (TB), and it also affords some protection against leprosy because Mycobacterium tuberculosis and Mycobacterium leprae are highly related. However, BCG is protective against leprosy to very varying degrees and only in some populations, and even where protection is observed it drops off over time. Leprosy remains endemic in some countries where BCG vaccination is widespread, so we clearly need to improve on BCG.
There are few leprosy vaccines in development, although three are currently in Phase 3 clinical trials which means they have shown promise and are now being tested on a large scale in many hundreds of subjects.
A successful leprosy vaccine would be a critical step in controlling the epidemic by preventing disease and transmission, and could be used in conjunction with other strategies, including better diagnostics, increased awareness, and the development of new drugs, to finally eradicate this disease.
How is VALIDATE helping?
At the VALIDATE Network, by bringing together leprosy researchers from around the world we hope to speed up progress towards an improved vaccine against this neglected disease.
Further information (find more on our Publications page)
How leprosy affects the body and the impact it can have on a person’s life – The Leprosy Mission
WHO Leprosy fact sheet
CDC Hansen's Disease webpage
International Leprosy Foundation (ILEP) Zero Discrimination campaign
New Face of Leprosy Project