Intro to mosquitoes
There are over 3,000 species of mosquitoes found worldwide, and 120 found in the United States. Mosquitoes are an annoyance because of their parasitic nature. They also can be a serious health hazard due to their ability to transmit blood borne parasites that cause disease.
Biology and behavior
Unfortunately, most people have encountered mosquitoes and with them, mosquito bites. What people might not know is the role these bites play in the mosquito biological cycle. Female mosquitoes require a blood meal to develop fertile eggs. Males, not having eggs, do not need blood meals and thus do not bite. The welts that result from mosquito bites happen because females inject saliva under the skin of hosts to prevent blood from clotting as it is sucked into the food canal. When people are allergic to the saliva, itchy welts are produced.
Since blood is used for reproduction only, not food, both males and females rely on sugar for energy. They get this from plant nectar, fruit juices, and oozing plants.
Mosquitoes are cold-blooded creatures; therefore, their activity level is based on the temperature. They thrive at 80 degrees, become lethargic at 60 degrees and can’t function below 50 degrees. Because of this temperature requirement, mosquitoes are active year-round in tropical climates and only in the summer in temperate climates. At the onset of cold in temperate climates, mosquitoes hibernate throughout the winter in places such as animal burrows, hollow logs, and basements.
Mosquitoes have four stages of development: egg, larva, pupa, and adult. In their larval and pupal stages, they stay in water, mainly still water. This is where the concept of mosquito control through water removal is important. By removing standing water from the premises of a property, removal of eggs, larva, and pupa is achieved as well. Many species overwinter in frozen water as eggs and, in the spring, emerge to start the cycle of reproduction again by seeking a bloodmeal and laying more eggs.
How exactly are mosquitoes attracted to people? The major way that they seek out hosts is by following the streams of carbon dioxide exuded through breathing. Other desirable factors include dark clothing, perspiration, and artificial fragrances from detergents, fabric softeners, and perfumes.
Mosquitoes and disease
Besides causing annoyances and minor discomfort, mosquitoes also cause disease. In fact, they are the most formidable transmitters of disease in the animal kingdom. Disease is transmitted when the mosquito picks up a parasite in the blood of a host. When inside the mosquito, the parasite will then continue in its life cycle, multiply, or change form. After laying eggs as a result of that bloodmeal, the mosquito will seek another host to continue laying more eggs. It is at this point that the parasite is transferred to the next host. Diseases transferred in this way are malaria, encephalitis, yellow fever, and West Nile virus amongst several others.
Prevention and elimination
To reduce the risk posed by mosquitoes, you need to reduce the risk of being bit. There are two ways to do this. The first is to eliminate population sources and the second is to protect your body. Following is a list of ways to reduce their breeding:
-Dispose of unwanted tin cans and tires
-Clean clogged roof gutters and drain flat roofs
-Flush sump-pumps weekly
-Stock ornamental pools with fish
-Change water in birdbaths, fountains, and troughs twice a week
-Clean and chlorinate swimming pools; when not regularly used, they should be emptied
-Turn over unused wading pools and other containers that tend to collect rainwater
-Cover containers tightly with window screen or plastic when storing rainwater for garden use during drought period
For personal protection for you and your family, follow these suggestions:
-Wear long-sleeved shirts and long pants
-Stay indoors at dawn and dusk when mosquitoes are most active
-Use mosquito netting on baby carriages and playpens when your baby is outdoors
-Make sure screens are repaired and tightly attached to doors and windows
-Avoid camping overnight near freshwater swamps to reduce your risk of exposure to mosquitoes
-Use mosquito repellent and follow manufacturer’s directions on the label
To expand on the last suggestion, to wear relent, there are certain precautions that should be taken when using DEET (N-N-diethyl-meta-toulamide) containing products. DEET can be applied to skin and clothing, but has the potential to damage certain fabrics and to be absorbed into skin. For this reason, no repellent with a concentration above 30-35% should be used on adults. Additionally, nothing over 10-15% should be used on children. Anything above 30-35% does not offer more protection, although it does last longer. In the interest of safety, it would be best to simply reapply repellent with a lower concentration of DEET. After your time outdoors, wash skin with soap and water and launder clothes that have been sprayed with repellent.