Anopheles gambiae; Culicidae family
Flying – Biting
The length of the body is rarely greater than 0.62 inches and the total weight is usually less than 2.5 milligrams.
The body of the adult Anopheles mosquito is dark brown to black in colour and has 3 sections which are the head, thorax and abdomen.
Males live for about a week, feeding on nectar and other sources of sugar. Females will also feed on sugar sources for energy, but usually require a blood meal for the development of eggs. After obtaining a full blood meal, the female will rest for a few days while the blood is digested and eggs are developed. This process depends on the temperature, but usually takes 2–3 days in tropical conditions. Once the eggs are fully developed, the female lays them and resumes host-seeking.
The cycle repeats itself until the female dies. While females can live longer than a month in captivity, most do not live longer than one to two weeks in nature. Their lifespans depend on temperature, humidity and their ability to successfully obtain a blood meal while avoiding host defences.
Malaria is transmitted among humans by female mosquitoes of the genus Anopheles. Female mosquitoes take blood meals to carry out egg production and such blood meals are the link between the human and the mosquito hosts in the parasite-life cycle. The successful development of the malaria parasite in the mosquito depends on several factors. The most important is ambient temperature and humidity (higher temperatures accelerate the parasite growth in the mosquito) and whether the Anopheles survives long enough to allow the parasite to complete its cycle in the mosquito host (“sporogonic” or “extrinsic” cycle, duration 10 to 18 days). Differently from the human host, the mosquito host does not suffer noticeably from the presence of the parasites.
Anopheles gambiae is one of the best-known mosquitoes, because of its predominant role in the transmission of the most dangerous malaria parasite species to humans, the Plasmodium falciparum.
Malaria is nowadays limited to tropical areas, most notoriously the regions of sub-Saharan Africa. The CDC (Center for Disease Control and Prevention) warns, however, that “Anopheles that can transmit malaria are found not only in malaria-endemic areas, but also in areas where malaria has been eliminated. The latter areas are thus constantly at risk of reintroduction of the disease.
Tips for Control
Complete control or elimination of malaria mosquitoes around any property is not possible. Mosquito reduction, however, is very possible and involves a number of components:
Habitat reduction; getting rid of any item that could contain water and hold it for more than seven days needs to be addressed.
Empty and refill birdbaths at least once per week.
Drill holes in the bottom of tire swings to prevent rainwater from accumulating.
Avoid using barrels or other containers to capture rainwater unless the container is emptied every few days.
Empty children’s “kiddie” pools regularly.
Examine gutters regularly. Conditions, such as debris or loose guttering, should be corrected.
Fill in accessible tree holes with a material that will not harm the tree. Check with a local nursery for advice.
Use soil to fill in low areas in lawns and landscaped areas that allow rainwater to collect and stand for more than seven days.
Install an agitator in garden ponds used in landscaping or buy fish that eat mosquito larvae. The wave actions created by an agitator can prevent mosquito adults from successfully emerging from pupae.
Controlling Mosquito Larvae: for properties that have ditches, small ponds or decorative garden ponds, environmentally friendly mosquito larvicides can be applied to the water by a pest professional in areas in which mosquitoes can breed.
The Insect Growth Regulator (IGR), methoprene, affects only insects, interfering with a mosquito larva’s ability to pupate into an adult. IGR products are generally applied about once every 30 days to help reduce mosquito populations.
Bacterial mosquito control products that affect only mosquito larvae also can be used, but such products require specific timing in order to obtain maximum results.
Controlling Adult Mosquitoes: the best way to limit mosquitoes is to prevent adult mosquitoes from developing by eliminating or treating breeding sources as described above. Because some adult mosquitoes are most likely always going to be present, treatments can be applied around a home to control as many as possible.
A pest professional can apply residual products to shrubs and other vegetation around the home and yard. Since mosquitoes spend most of their time during the day resting in vegetation, such treatments can effectively reduce mosquito populations. Such treatments need to be periodically reapplied during the warm months when mosquitoes are active.
Some of the mosquito traps available commercially do attract and capture large numbers of mosquitoes. Concern may exist that such traps may draw mosquitoes from adjacent properties, so locating the trap at the perimeter of the property is preferable to placing it next to the patio, deck, etc. where people are active.
Mosquito control treatments are available in some areas of the country. Consult your pest control professional for tips and assistance in reducing mosquito populations.
Malaria control is carried out through the following recommended malaria treatment and prevention interventions. The choice of interventions depends on the malaria transmission level in the area.
Case management (diagnosis and treatment) of patients with malaria
o Insecticide-treated nets (ITNs)
o Intermittent preventive treatment of malaria in pregnant women (IPTp)
o Intermittent preventive treatment of malaria in infancy (IPTi)
o Indoor residual spraying (IRS)
o Indoor and outdoor mosquito traps.
Occasionally, other interventions are used:
Larval control and other vector control interventions
Mass drug administration and Mass fever treatment
In addition, several companies and groups are at work on developing a malaria vaccine, but there is currently no effective malaria vaccine on the market.