Hansen disease (i.e. Leprosy) is a chronic infectious disease caused by a type of bacteria, Mycobacterium leprae.

Leprosy is a neglected tropical disease (NTD) which still occurs in more than 120 countries, with more than 200 000 new cases reported every year. Elimination of leprosy as a public health problem globally (defined as prevalence of less than 1 per 10 000 population) was achieved in 2000 (as per World Health Assembly resolution 44.9) and in most countries by 2010.

The disease predominantly affects the skin and peripheral nerves. Left untreated, the disease may cause progressive and permanent disabilities.

The bacteria are transmitted via droplets from the nose and mouth during close and frequent contact with untreated cases.

WHO released the Towards zero leprosy: global leprosy (Hansen’s disease) strategy 2021–2030 aligned to the neglected tropical diseases road map 2021–2030.

Leprosy is a curable disease. The currently recommended treatment regimen consists of three drugs: dapsone, rifampicin and clofazimine. The combination is referred to as multi-drug therapy (MDT). The duration of treatment is six months for PB and 12 months for MB cases. MDT kills the pathogen and cures the patient. Early diagnosis and prompt treatment can help to prevent disabilities. WHO has been providing MDT free of cost. Free MDT was initially funded by The Nippon Foundation and since 2000 it is being donated through an agreement with Novartis.

(WHO 2022)

Delay in detection is evidenced by the relatively high proportion of new cases with grade 2 disabilities. Causes may include lack of capacity to diagnose, lack of a point-of-care diagnostic test to detect leprosy infection or disease, weak case finding and contact tracing programmes, lack of community awareness, and the stigma associated with leprosy.

(WHO 2021. Towards Zero Leprosy. Global Leprosy (Hansen’s Disease) Strategy 2021–2030))