Along with the arrival of rainy season, many ditches and pits get full of rain water. This rain water remains in such ditches for many days which is even known as stagnant water. And we already know that stagnant water is the breeding place for many harmful insects such as Mosquitoes. Mosquito bites can be taken as one of the greatest problems that get created in the rainy season. Due to the mosquito bites, people and other animals not only get irritated but also they have to be victims of many dreadful diseases such as Malaria, Elephantiasis, Dengue Fever, Yellow fever, Encephalitis etc. In order to control mosquitoes and prevent such kind of dangerous diseases, there are some methods which can be adopted in order to destroy the mosquitoes and their habitat. The methods are described below in points:
1. Destruction of Breeding Places
The larvae and pupae of mosquitoes develop in stagnant water; therefore destruction of breeding places is a must. Swampy areas and stagnant water should be drained out. Water should also be prevented from standing in gutters, drains and depressions. The domestic species can be largely controlled by eliminating receptacles that hold water such as tincans, buckets, cisterns, barrels etc. The breeding grounds may also be filled up if possible. Similarly, the bushes and shrubs should also be cleared off.
2. Destruction of Larvae and Pupae
If it is not possible to fill up or drain out the swamps or lakes and ponds, the larvae and pupae may be killed by covering or spraying the surfaces of water with petroleum, paraffin oil, crude oil or kerosene oil These substances produce a thin film of oil on the surface so that the larvae and pupae of the mosquitoes die due to suffocation or lack of respiration. The oil also enters the spiracles, blocks the tracheae and poisons the whole body. Oil solutions or emulsions of DDT and Benzene Hexachloride are effective larvicides. Larvicidal fishes like sticklebacks, minnows, trouts etc. should be introduced in the ornamental fountains, ditches, ponds, lakes, canals, tanks etc. Aquatic nymphs and adult insects (dragon flies), which are natural enemies of mosquitoes should be encouraged. Keeping the lakes, reservoirs and streams free of aquatic vegetation and other floating material provides the top-feeding minnows (Gambusia) better opportunities to search out and feed upon the larvae and pupae.
3. Destruction of adult mosquitoes
The main habitat of adult mosquitoes are the houses of human beings. Mosquitoes should be driven out of the houses or killed by fumigation with substances like pyrethrum, sulphur etc. Occasionally spraying of houses and adjoining lands with DDT, flit pyrethrum and other insecticides prove useful. Residual sprays of DDT may remain effective for several months.
4. Defence against Mosquito Bites
Houses in mosquito-infected areas should be made mosquito-proof by screening all the doors and windows. While sleeping, mosquito nets, mosquito repellent liquids etc. should be used to keep away the mosquitoes. The exposed parts of the body may be protected by the use of veils, gloves and boots, or by the application of repellents such as anti-mosquito creams, mustard oil, mixture of kerosene oil and eucalyptus oil or cintrinella and coconut oil etc.