Mosquitoes transfer parasites and diseases that kill millions of people every year. While Africa currently suffers the most fatalities from mosquito-borne illnesses (primarily malaria), the rest of the world is not immune to the illness and sorrow mosquitoes can bring.
The Facts
Most types of female mosquitoes enjoy animal and human blood. When mosquitoes bite (using a needle-like appendage--mosquitoes don't have teeth), they release saliva into the victim's bloodstream. A mosquito's saliva contains blood-thinning substances as well as substances that cause the well-known swelling and itchiness. This release of saliva doesn't just cause discomfort--it is also how parasites and diseases transfer from mosquitoes to humans or animals.
Risk Factors
Mosquito bites put many people at risk for malaria, West Nile virus, dengue fever, yellow fever, several varieties of encephalitis, and other diseases. Malaria and yellow fever are currently not a problem in North America, but both diseases are prolific in Africa and parts of South America. In North America, mosquitoes sometimes carry La Crosse encephalitis, Eastern Equine encephalitis, Western Equine encephalitis, St. Louis encephalitis, or West Nile virus. Less common in North America, but still of concern for some southern states, is dengue fever.
People aren't the only creatures to suffer from mosquito-borne illnesses--pets can get heartworm from mosquitoes infected with the parasite. Some topical flea medicines provide some protection against mosquitoes---however, only heartworm preventatives offer full protection from heartworm. There have also been cases of encephalitis and West Nile virus in pets, and other animals, bitten by mosquitoes.
Identification
There are about 3.000 varieties of mosquitoes worldwide. Anopheles mosquitoes are responsible for transmitting malaria. Culex mosquitoes are the primary carriers of West Nile virus. (See Resources for photos.)
Time Frame
Within a few minutes to a few hours after a mosquito bites, the bite itches and inflammation appears. If the mosquito has transferred West Nile or another disease, symptoms may also appear within as little as a few hours, though usually several days pass before any symptoms appear.
Geography
Mosquitoes prefer warm temperatures and must have access to standing water in order to breed. They live anywhere that gets warm enough at least once a year. The minimum temperature for mosquitoes to develop is approximately 50 degrees Fahrenheit. Areas that do not reach above this temperature, any season of the year, rarely have a mosquito problem. Most of the world, therefore, is home to mosquitoes.
Significance
If global temperatures continue to increase, as some scientists predict, mosquitoes will become a bigger problem than they already are. Vigilant mosquito control and personal protective measures may be necessary in more regions to prevent common mosquito-borne illnesses. Using bed nets and mosquito repellent, and avoiding outdoor activities at dusk and dawn are some of the primary ways you can avoid mosquito bites and the diseases they transmit.
Tags: West Nile, Nile virus, West Nile virus, North America, dengue fever, encephalitis West, encephalitis West Nile