Mosquitos

Mosquito-borne diseases affect millions of people worldwide each year. In the United States, some species of mosquitoes can transmit diseases such as encephalitis, dengue fever, and malaria to humans, and a variety of diseases to wildlife and domestic animals. To combat mosquitoes and the public health hazards they present, many states and localities have established mosquito control programs. These programs, which are based on surveillance, can include nonchemical forms of prevention and control as well as ground and aerial application of chemical and biological pesticides.

Mosquitoes develop from two main sources: local breeding in standing water, and flying in from nearby breeding areas. Many problems with mosquitoes can be traced to backyard containers of water such as children’s toys, pots and cans, tire swings, urns, animal tracks and plugged rain gutters. Nearby areas include cemetery pots, construction sites and trash dumps. Most mosquitoes remain within a mile of their hatching place, however, the floodwater mosquitoes fly many miles.

The harmful form of the mosquito is the female which in most cases must have a blood meal before laying eggs. The females’ persistent search for blood brings them into households and yards where their contact with people results in an annoying pest situation. Other than a localized reaction to the saliva injected by the female while withdrawing blood, there is no damage from the annoying bites, but certain mosquitoes are vectors of human diseases such as eastern equine encephalitis (EEE), West Nile encephalitis, and canine heartworm that is transmitted to healthy dogs.

You can do much to control mosquitoes in your neighborhood. Check surrounding areas for mosquito breeding spots. If a dump area with standing water is located, local residents can cooperate in a cleanup operation.

The most effective way to control mosquitoes is to eliminate standing water that serves as prime breeding areas. Excluding mosquitoes from the house is necessary also. Chemical treatment of breeding sites and/or the house may be indicated.

To eliminate mosquito breeding from the property, one must locate and eliminate standing water. Some typical actions include:

• Remove old tires, tin cans, buckets, glass jars, broken toys, and water-catching objects.
• Check rain barrels for mosquito larvae. A tight cover will prevent egg laying. A thin layerof oil will kill mosquitoes already present.
• Keep swimming pools covered when not in use. For pools in use, the filtering action should eliminate mosquitoes. Small wading pools provide excellent breeding places. Change the water in wading pools frequently.
• Change water in bird baths by flushing with a hose at least once a week.
• Fill tree holes with sand or cement or drill holes to allow drainage.
• Examine rain gutters to see that water runs freely; remove leaves that may block water flow.
• If you have a flat roof, check for standing water several days after a rain.
• Check flower pots and drain for excess water.
• Ponds with fish are not a problem, since fish feed on wrigglers and tumblers. Dense vegetation prevents fish from finding the mosquitoes. Clean out vegetation, particularly from pond edges.
• The mosquito-eating fish "Gambusia affinis" and goldfish are planted in many impoundments and waterways. A single "Gambusia affinis" may consume over a hundred mosquito larvae in one day.

Keep mosquitoes out of the house with adequate screening. For mosquitoes inside the house, use a fly swatter or an aerosol insecticide labeled for flying insects.

Repellents can help maintain personal comfort outside the house. Since people vary in their attractiveness to mosquitoes, the success and length of effectiveness of any one repellent depends somewhat on the individual.

Repellents can protect humans from mosquito bites for one to five hours, depending on the amount of perspiration and rubbing of the skin and abundance of mosquitoes. Evenly cover the areas of the skin to be protected because mosquitoes will bite untreated spots. Spray on the outer clothing and on exposed parts of the body.

Be sure to keep the windows, doors and porches tightly screened to exclude as many mosquitoes as possible. Avoid spraying food, dishes and other eating utensils.