A severe form of leishmaniasis characterized by irregular bouts of fever, substantial weight loss, swelling of the spleen and liver, and anemia (which may be serious). If left untreated it may lead to death. Two species of Leishmania are known to give rise to the visceral form of the disease. The species commonly found in East Africa and the Indian subcontinent is L. donovani and the species found in Europe, North Africa, and Latin America is L. infantum, also known as L. chagasi. The disease is Monarch Disease Ontology term MONDO_0005445 (visceral leishmaniasis). Also known as: infection by visceral leishmaniasis, kala-azar, viscus leishmaniasis.