what strategies are adopted to control mosquitoes.
Control of mosquito populations will depend on the mosquito species:
1. Anopheles – malaria
There are various strategies to control the Anopheles mosquito:
A. To Reduce the Source:
1. Site selection: From a malaria control perspective, any displaced population camp or evacuation site should be located one to two kilometers upwind from potential vector breeding sites whenever an additional clean water source can be provided for the camp population. In this case they have less direct need to be sited close to natural water sources.
2. Environmental control: If the Anopheles breeding sites are limited and circumscribed then larval control may be possible through draining or applying a larvicide. Anopheles funestus breeds in permanent water bodies with
vegetation, including ponds and swamps.
3. Chemical and biological control: If larviciding is chosen, there are only two main larvicides that can be safely applied on water that is used for drinking.
a. temephos (an organophosphate insecticide better known as Abate) widely used in control of dengue, onchocerciasis, and guinea worm
b. Bacillus thuringiensis israelensis (a biological insecticide)
B. To Minimise Transmission: For control against the adult Anopheles mosquito, it is important to remember that species generally bites late in the night. Therefore, if repellents coils, fumigants, and aerosol sprays are applied in the early evening.
the protection they provide may not last long enough to have a significant impact. Where available, repellants and coils may be in use on an individual basis and theiruse should be encouraged
2. Aedes – yellow fever and dengue
a. Aedes aegypti is a daytime biting mosquito that does not rest on walls. It prefers to rest on hanging clothing..
Therefore, neither insecticide-treated materials (ITMs) nor indoor residual spraying are effective control measures.
Many programs carry out space spraying with thermal fogs or ultra-low volume insecticides. This is very expensive, but may be necessary during epidemics and should always be combined with larval control
b. The following three methods are effective for larval control:
Environmental sanitation: Clean-up, bury or dispose of “non-essential” water containers, including old tires, tin cans, broken jars, plastic bottles, etc.
Prevent breeding: empty and clean domestic water containers once a week. Since it takes 10 days for the mosquito to develop from egg to adult, cleaning and covering the jars once a week will prevent adults from emerging.
Use larvicide such as temephos (Abate),
डेंगू , मलेरिया मच्छरों से बचने के उपाये | Pesticide for mosquito control | How to control mosquitos
3. Culex quinquefasciatus Culex mosquitoes are more often nuisance biters and are less easily controlled by insecticide-treated mosquito nets or residual house spraying. Larval control can be achieved through environmental sanitation,
improved latrines, and applying insecticides, oils, and polystyrene beads on the surface of pit latrines and cesspools.
4. Explain how non biting flies are controlled.
There are various strategies to control non-biting fly populations:
To Reduce the Source:
a. The most important control measure is to ensure there are enough fly proof latrines:
- Provide a water seal or functioning VIP latrines.
- Provide covers for other types of latrines.
- If defecation fields are used in the early stages of a refugee settlement, they should be at least 500 metres down wind from the nearest household and 30 metres from a water source.
b. Asecond important control measure is to regularly dispose of all garbage.
- Collect refuse from households, markets as well as from refuse sites at least twice a week in order to limit the number of flies that reproduce.
- All refuse should be finally disposed in covered garbage pits or by burying. The Shaded, damp environment with organic matter mixed with mud provides a perfect breeding site for houseflies and bottle flies.
c. Dead animals and wastes from slaughter houses should be buried as soon as possible.
Explain how biting flies are controlled. what strategies are adopted to control mosquitoes.
It is important to control biting flies such as tsetse_flies, sandflies wherever they cause major disease epidemics
1. Tsetse Fly sleeping sickness There are various ways of controlling tsetse fly populations.
a. Traps: The biconical trap, pyramidal trap and vavoua trap are made up of blue and black cloths and mosquito netting. Flies get attracted to the brightly colored mosquito netting over the traps and are unable to escape after
entering. Traps are cheap, easy to transport, completely safe for the user and very effective means for control of biting flies. Because they do not require any specific training to use, they are ideal for use by individuals or communities.
b. Insecticide Treated Targets: these consist of impregnated traps and screens, which are more effective since they kill any flies that land on them. They may be impregnated by the same pyrethroids used for impregnating
mosquito nets (may be effective for upto 3 months).
c. Insecticide Spraying: Aerial and ground spraying of insecticides may be the preferable method of control during acute epidemics of sleeping sickness, river blindness or leishmaniasis. Daytime resting places such as tree trunks, twigs and roots should be target, Because of its high cost, need for special equipment and trained workers,
spraying is not recommended as a routine control measure.
Traps attract more flies than screens and require less handling. Screens are much cheaper than traps and can cover a larger area. However, traps continue to be effective in catching flies once the insecticide wears out, screens are only effective as long as the insecticide is active.
2. Sandflies – leishmaniasis
The infection and spread of leishmaniasis may be controlled in the following ways:
- Personal Protection: avoid being bitten by keeping away from areas that sandflies are known to breed or rest, and by using bednets, repellents, clothing
- Residual Spraying: although spraying the interior and exterior sides of doorways and windows, and the inner walls is effective against indoor-resting sandflies, malaria control is the primary reason for spraying wherever leishmaniasis is a problem.
- Control of animal reservoir : controlling the animal reservoir population eine rock hyrax in Ethiopia, dogs or other domestic animals) may reduce the incidence of leishmaniasis.
Also Read This