Kala-Azar

Definition

The most severe and often fatal form of leishmaniasis, characterized by fever, hepatosplenomegaly, pancytopenia, and hyperpigmentation of the skin; caused by protozoan parasites of the genus Leishmania (L. donovani, L. infantum, or L. chagasi) and transmitted to humans through the bite of infected female phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae). The term derives from Hindi 'kala' (black) and 'azar' (fever or disease), referring to the darkening of the skin in advanced cases. Kala-azar represents a critical interface between vector biology, parasitology, and public health in tropical and subtropical regions.

Etymology

Hindi kala (black) + azar (fever, disease), descriptive of the characteristic skin hyperpigmentation

Example

In the Indian subcontinent, Phlebotomus argentipes is the principal vector of kala-azar, with control efforts targeting breeding sites and residual insecticide spraying of dwellings.

Synonyms

• visceral leishmaniasis
• black fever
• dumdum fever

Related Terms

• Leishmaniasis
• phlebotomine
• Sand fly
• vector-borne disease
• Leishmania
• cutaneous leishmaniasis
• mucocutaneous leishmaniasis
• protozoan parasite
• Zoonosis

Usage Notes

Now largely replaced by 'visceral leishmaniasis' in scientific literature, though 'kala-azar' remains common in South Asian clinical and epidemiological contexts. The term specifically denotes the visceral form; do not use for cutaneous or mucocutaneous leishmaniasis. In entomological contexts, emphasizes the role of phlebotomine sand flies as obligate vectors and reservoir maintenance in canid or rodent hosts.