Matriz de codificación axial 1

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pulmonary edema are more common in pregnant women with P falciparum infections.

Pregnant women should be treated promptly with appropriate doses of antimalarials.

Quinine does not appear to induce labor as was once thought. Pregnant women with chloroquine-sensitive P vivax infections should be treated with chloroquine to eliminate the erythrocyticstage infection and then placed on weekly chloroquine to prevent relapse, as the safety of primaquine in pregnancy is not known (CDC, 1996).

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Most control operations are targeted against three different problems; Nuisance mosquitoes which bother people around homes or in parks and recreational areas.

Economically important mosquitoes which reduce real estate value, adversely affect tourism and related business interests or negatively impact livestock orpouffiy production.

Public health which is the focus when mosquitoes are vectors or transmitters of infectious diseases (CDC, 2006). Depending on the situation, source reduction, biocontrol larviciding (control of larva) or adulticiding (control of adults) may be used to manage mosquito population. The techniques are accomplished using habitat modification, pesticide, biological-control agents and trapping (Cheviilon et al., 1999). Control of adult mosquitoes is the most farmiliar aspect of mosquito control to most of the public. It is accomplished by ground based application of chemical pesticides. Generally, modern mosquito control programs in developed countries use low volume application of pesticides.

Dichlorodiphenyl - Trichloroethane (DDT) was formerly used throughout the world for large area mosquito control but it is now banned in most developed countries and controversially remains in common use in many developing countries since insecticides still remain the cornerstone of control strategy (CDC, 2006).

Other methods include a light trap that attracts and captures mosquitoes. A newer approach to killing mosquitoes in a non-toxic way is to use a device that burns propane, thus generating CO2, warmth and water vapour. These three elements, often coupled with a chemical attractant heated in this process, draws the mosquitoes towards the propane flame, where they are then sucked into a net or holder where they collect (Cheviilon et al., 1999).

A traditional approach in controlling mosquito population is the use of lethal ovitrap by providing artificial breeding spots for the mosquitoes but destroy the developing larvae.

Another approach is to focus attention on larvicides. Mosquito NETS and mosquito

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screening can reduce the risk of acquiring malaria and other mosquito borne diseases (Chevillon et al, 1999) and FMH 2010).

2.6.1 Biological Control

Biological control is the use of living organism to control a vector. Biological control methods are very important in protecting the public from mosquitoes. The primary biological control we use is the mosquitofish, Gambusia affinis. The mosquitofish preys on mosquito larvae allowing us to keep mosquito populations under control (WHO, 2005a).

The Fisheries Department is responsible for breeding mosquitofish and other fish species that prey on mosquito larvae. Mosquito-eating fish are readily available for our field technicians and to the general public through a service request program. We maintain 23 ponds which produce 2000-7000 pounds of fish annually. Today, we are one of the largest mosquitofish producing facilities in the nation. The most successful biological tool against immature mosquitoes in California is the mosquitofish, Gambusia affinis. When introduced to a mosquito breeding source, the mosquitofish quickly adapts, multiplies and is capable of controlling mosquitoes in a given area (CDC, 2006).

The mosquitofish, a live-bearing American fish, is utilized as a predator of mosquito larvae in many diverse aquatic habitats. A small species, the full-grown females are usually less than 2½ inches in total length, while males are typically under 1½ inches. The muted silver and light olive green body color is common to both sexes. In addition, they are able to lighten or darken their body color to closely match their immediate environment (Greenwood, 1997). Fish such as guppies, which breed rapidly and eat mosquito larvae, are valuable especially in water tanks, and other enclosed water collections.Two bacteria which produce toxin and kill larvae which eats them are Bacillus thuringiensis and B. shaerirus

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(Numerous other mosquito pathogens and predators have been tried:- viruses, bacteria, protozoa, fungi and nematodes worms. Male mosquito can be sterilized by chemicals or x-ray fat will still mate. Release of large number of infertile males can reduce mosquito breeding because the female's Anopheles mate once in her life time. Some species of frogs feed on mosquitoes and other insects and this could also served as biological control measure for mosquitoes (CDC, 2006).

2.6.2 Environmental Control

This include all methods of reducing the number of breeding site of mosquito such as drainage, edge of stream, old tyres, abundant containers, grasses and vetations clearance,proper refuse disposal and properly constructed gutters to allow flow of water and dirts. Other relevant methods in the environmental control of mosquitoes include steps that can take to reduce mosquito populations without using insecticides. Elimination of important breeding sites aimed to prevent mosquito bites such flower pots, birdbaths, pet water dishes, cans, gutters, tires and buckets regularly to disrupt the mosquito breeding cycle, keeping windows and door screens in good working order to prevent mosquitoes from entering your home (WHO, 2005a).

If possible, the use of long-sleeved shirts and long pants while outdoors should be practiced, protective measures while staying indoors early in the morning and evening when mosquitoes are most active. Maintainance of swimming pool to prevent mosquito breeding, and report abandoned pools to your local health department and the use of mosquito netting over infants carriers when infants are outdoors. It is also important to consider using an insect repellent, be sure to follow the label directions for applying the repellent. For help selecting a mosquito repellent, try our Insect Repellent Locator (CDC,

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2006). Insecticides are usualyl used to help control mosquitoes. Some products are designed to be applied directly to water to control mosquito larvae, while others are used more broadly to control adult mosquitoes. Some community agencies provide mosquito control as a service to the public and may apply pesticides by trucks or planes. Visit the links below to get more information about how to control mosquitoes (CDC, 2006).

2.6.3 Personal Protection

Precaution is the best self care for malaria infection. Sensible precaution by individual to avoid mosquito bites reduce substantially both the risk and the transmission of malaria e.g weaving clothes with long sleeves and trouser at night, proper use of net preferably with one impregnated with residual insecticide in houses. Electronic vaporizers are commendable during sleeping hours. Use of prophylactics drugs as recommended, use of repellants on exposed skin, use of insecticide (Chen et al., 2000). Exmpls includes wearing of protective clothes, sleeping under protective or insecticide treated mosquitoes nets and limiting the number of hours of stay outdoors at nights to prevent outdoor human mosquitoes bites.