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- Mosquitoes have had a big impact on human history -

Summary: Mosquitoes are probably the most important of all insects in terms of their direct impacts on human health. Mosquito-borne diseases like malaria still account for millions of deaths annually world-wide and contribute to global poverty by sickening whole communities.

Jack DeAngelis, PhD
OSU Ext. Entomologist (ret.)

What are mosquitoes?

Mosquitoes are small, delicate flies (see drawing lower right) that have had a huge impact on human history. Their extremely annoying bite carries with it the possibility of disease. Malaria, yellow fever, and, more recently, West Nile virus are a few of the better known mosquito-transmitted human diseases. Malaria alone kills millions of people each year worldwide and contributes to global poverty by weakening entire populations.

Other animals suffer from mosquito-borne illness as well. West Nile virus is often fatal to birds and horses, and heartworm is a very serious and often fatal mosquito-borne disease of dogs (see Related Articles below for more information).

Mosquitoes develop in standing water

Mosquito larvae (see picture top right) develop in standing water and breathe air either through a siphon tube or by swimming to the water surface. Even the water in small puddles or ornamental ponds and faulty rain gutters can support many larvae. Female mosquitoes require a blood-meal to produce healthy eggs. During feeding disease organisms may be transmitted to the host animal in the mosquito's saliva.

common misspellings and alternate names: mosquitos, mosquito repelants, mosquito repellants, mossie, skeeters

yellow fever mosquito larvae
mosquito adults (line drawing)

Yellow fever mosquito larvae (top) suspended, head down, from water surface by siphon tubes. Line drawing (bottom) of adult mosquitoes.

Mosquito control

Protection from mosquito bites and the diseases they can spread involves (1) control of mosquito larvae and/or biting adult mosquitoes, (2) elimination of temporary breeding sites and (3) use of insect repellents and bed nets (see Using Insect Repellents and How to Control Mosquito Larvae In Standing Water). A variety of mosquito control products can be found here (DoMyOwnPestControl).

Mosquitoes tend to be more of a problem in warm tropical climates and less so in cool dry climates. However, mosquitoes occur on nearly every continent and are more often correlated with bodies of standing water like lakes and ponds rather than air temperature. As an example, cold high mountain lakes in the Pacific Northwest are notorious for swarms of biting mosquitoes.

Diseases transmitted by mosquitoes

In the US West Nile virus and heartworm are now the most important mosquito transmitted diseases. West Nile virus can cause serious human illness in a small percentage of the population but is also causes fatal disease in horses and birds. Heartworm is a nematode that causes an often fatal disease in dogs and other unprotected animals.

In many parts of the world malaria is still the most important mosquito-borne illness. And, until a vaccine was developed yellow fever epidemics routinely swept through populations killing hundreds or thousands of people each year.

Related Articles

Using Mosquito Traps for Adult Mosquitoes

What is Malaria?

What is West Nile Virus?

What is Heartworm in Pets?

'Bugs Needs Your Support!




Jack DeAngelis, Ph.D.

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