Mosquito, the most dangerous insect pest to man. Most species of mosquitoes are harmless. However, several species carry and transmit diseases. Mosquitoes are the only agents that carry and transmit malaria, yellow fever, dengue fever, and filariasis to man. They are leading agents in transmitting several forms of viral encephalitis. Mosquitoes also transmit certain diseases to animals.

Mosquitoes inhabit nearly all parts of the world except deserts. They have been found at altitudes of 14,000 feet (4,300 m), and some species live within the Arctic Circle. They have made some areas uninhabitable by man.

There are more than 3,000 known species of mosquitoes, divided into about 100 large groups, or genera (singular: genus). Among the best-known groups in North America are the Culex, the Aedes, and the Anopheles. In the United States, two species of Anopheles transmit malaria. Two species of Aedes and two species of Culex transmit viral encephalitis.

Facts in brief about mosquitoes
Number of eggs: 50 to 200 at a time, depending on species. As many as 1,000 a year for each female.
Length of life: 30 days or more for females; about 7 to 10 days for males.
Where found: All parts of the world.
Scientific classification: Mosquitoes make up the mosquito family, Culicidae. The scientific name of the common house mosquito is Culex pipiens. The yellow fever mosquito is Aedes aegypti, and the Asian tiger mosquito is A. albopictus.