Visceral leishmaniasis: a forgotten epidemic

Abstract

Visceral leishmaniasis (VL or kala-azar) is most endemic in Asia and Africa and commonly affects young children. It is usually caused by Leishmania donovani or Leishmania infantum that are transmitted by Phlebotomine sand flies. Transmission may be anthroponotic or zoonotic or both, depending on the endemic area. Clinical features include fever, hepatosplenomegaly, weight loss and pancytopenia. Younger age, malnutrition and immunosuppression (HIV infection, use of immunosuppressive drugs) are risk factors. Many infections remain asymptomatic. Diagnosis is made by demonstration of the Leishmania parasite in aspirates of lymph node, bone marrow or spleen. Serological tests such as rK39 strip test are widely used but the sensitivity varies. qPCR is useful to detect low numbers of parasites and to monitor treatment. Treatment is with AmBisome monotherapy in most areas but with drug combinations elsewhere. HIV co-infected patients are most difficult to treat and often relapse. Control efforts focus on case finding, availability of diagnostic tools, reservoir control and protection from sand flies (insecticides, bed nets). There is no human vaccine.

Geo‐climatic factors in a newly emerging focus of zoonotic visceral leishmaniasis in rural areas of north‐eastern Iran

“…The clinical manifestations range from self‐limited but chronic cutaneous leishmaniasis (CL) to disfiguring muco‐CL (MCL) and fatal visceral leishmaniasis (VL) that is often incurable if left untreated (WHO, ). VL is endemic in 79 countries and mostly found in South Asia, South and Central Americans and horn of Africa and with a lower prevalence in the Far East, Central Asia, the Middle East and the Mediterranean Basin (Alvar, ; Zijlstra, ). L. donovani is mainly found in Africa and the Indian subcontinent as causative agent of anthroponotic VL (AVL), and L. infantum/chagasi is the most important causative agent of zoonotic VL (ZVL) in Americans, the Mediterranean Basin, the Middle East and other endemic areas.…”

“…L. donovani is mainly found in Africa and the Indian subcontinent as causative agent of anthroponotic VL (AVL), and L. infantum/chagasi is the most important causative agent of zoonotic VL (ZVL) in Americans, the Mediterranean Basin, the Middle East and other endemic areas. L. infantum/chagasi has a zoonotic cycle that often involves infants and children in endemic regions where dogs and other canids are the main reservoirs of the parasite (Schonian, Mauricio, & Cupolillo, ; Zijlstra, ).…”

Population structures of Leishmania infantum and Leishmania tropica the causative agents of kala-azar in Southwest Iran

“…Leishmaniasis is a complex of neglected tropical diseases, caused by different species of Leishmania, which are present in five continents (Zijlstra 2016). Visceral leishmaniasis (VL) is the most severe form of disease and is potentially fatal if untreated.…”

“…VL causing species vary geographically, Leishmania donovani in South Asia (Bern et al 2007;Rijal et al 2010;Singh et al 2010) and East Africa (Elnaiem 2011;Zijlstra 2016), and Leishmania infantum (L. chagasi) in Central and South America, the Middle East, Mediterranean Basin, Central Asia and China (WHO 2010). VL caused by Leishmania tropica, a species that causes Old World cutaneous leishmaniasis (CL), has been reported sporadically in humans in South Asia and humans and dogs in the Middle East and North Africa (Mebrahtu et al 1989;Guessous-Idrissi et al 1997;Alborzi et al 2006;Hajjaran et al 2007;Khanra et al 2012;Hosseininasab et al 2014).…”

Pediatric Visceral Leishmaniasis Caused by Leishmania infantum in Northern Cyprus

“…In such patients, symptoms may be nonspecific, with overlap between those of the underlying disease and VL, with fever absent and pancytopenia and weight loss the only signs reported 5,6…”