NTDs are a diverse group of 20 diseases that prevail in tropical and subtropical climates.

These diseases disproportionately affect the poorest and the most marginalized communities, primarily women and children. Data from a landmark study in 2013 showed that NTDs were responsible for the loss of 17 million healthy years globally that year, with a high proportion being lost in sub-Saharan Africa.

(FIND 2023)

• Leishmaniasis is caused by protozoan parasites which are transmitted by the bite of infected female phlebotomine sandflies.
• There are 3 main forms of leishmaniases: visceral (the most serious form because it is almost always fatal without treatment), cutaneous (the most common, usually causing skin ulcers), and mucocutaneous (affecting mouth, nose and throat).
• The disease affects some of the world’s poorest people and is associated with malnutrition, population displacement, poor housing, a weak immune system and lack of financial resources.
• An estimated 700 000 to 1 million new cases occur annually.

(WHO Leishmaniasis key facts 2023)

Leishmaniasis is caused by a protozoa parasite from over 20 Leishmania species. Over 90 sandfly species are known to transmit Leishmania parasites.

In visceral leishmaniasis, diagnosis is made by combining clinical signs with parasitological, or serological tests (such as rapid diagnostic tests). In cutaneous and mucocutaneous leishmaniasis serological tests have some value and clinical manifestation with parasitological tests confirms the diagnosis.

(WHO, Leishmaniasis Key Facts 2023)

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.

Leprosy is curable with multidrug therapy (MDT).

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