Which of the following is NOT mosquito borne disease ?

The correct answer is C. Sleeping sickness, or human African trypanosomiasis, is caused by the protozoan Trypanosoma brucei and is transmitted by the tsetse fly (Glossina), not a mosquito. It is largely confined to sub-Saharan Africa.

The other three are classic mosquito-borne diseases:

• Dengue fever is caused by a flavivirus and spread mainly by Aedes aegypti.
• Filariasis is caused by filarial worms such as Wuchereria bancrofti and is spread mainly by Culex quinquefasciatus.
• Malaria is caused by Plasmodium and spread by female Anopheles mosquitoes.

The core concept is vector-borne disease, meaning the specific vector and pathogen pair. In India, the National Vector Borne Disease Control Programme under the Ministry of Health covers malaria, dengue, filariasis, kala-azar, Japanese encephalitis and chikungunya. For Mains, this links to public health governance and the Sustainable Development Goals on disease control.

Trap: Aspirants assume every tropical parasitic disease is mosquito-borne. Kala-azar is sandfly-borne, and sleeping sickness is tsetse-borne.