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How to combat dengue

November 17, 2011

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DENGUE is caused by a viral infection. You suffer from high fever with the body temperature being anything from 103 degrees F to 105 degrees F. Your entire body pains.

Besides, there is severe vomiting, loss of appetite and wastage of white blood cells (causing failure of the defence mechanism of the body). In case of a severe attack, there is cerebral failure, causing death.

So far, no preventive or curative medicine has been found. The patient automatically returns to normal within seven to 10 days. However, the disease leaves the patient so weak that s/he becomes unable to perform any work for about four to six weeks.

The virus is transmitted from a sick person to a healthy person through a certain species of mosquito. The mosquito lives on blood (preferably human blood). Its life during a favourable climate (25 degrees F to 35 degrees F with 60 to 70 per cent humidity) is up to 35 days. It sucks human blood every 48 hours to complete digestion. After taking its meal, it takes rest under the leaves of bushes, on trees, grass, etc.

On completion of digestion of the meal, the ovary becomes fully mature to deliver eggs. Thus it goes out of its resting place and finds out fresh water to drop the eggs. For this purpose, it may move within a one km radius.

After laying its eggs, it flies back to the same place from where it had flown. For laying eggs, it leaves its resting-place just before sunset and comes back for a meal soon after.

Since it lays eggs on clean water, therefore, edges of canals, streams, watercourses, agricultural fields, beds of flowering plants, lawns, abandoned utensils, pots lying on roofs, old tires, etc., are the best places for the purpose.

Transmission season: Ideal temperature and humidity is available in this part of the globe from July to October (monsoon season). A small period from the end of February to early April (also) is suitable for the mosquito to carry on the activity.

To suck blood, nature has bestowed the creature with piercing and sucking mouth parts (called proboscis) which is similar to syringe. It pierces the proboscis in the human body and sucks the blood. Small children and women are preferred victims but others are not disliked. After sucking its meals it rests for several hours before leaving the place for laying eggs.

How to combat? In towns and cities, larvae-ciding is the most effective method for controlling the mosquito. However, in rural areas where agricultural crops are sown and irrigation water is applied every seven to 10 days, larvae-ciding is not possible. The only way to contain the mosquito is through adulticiding.

Methodology: It is unfortunate that all government departments concerned are incapable of planning and executing the larvae-ciding or adulticiding. The operation needs to be planned out on a war footing and carried out as a campaign with dedication and spirit to a high degree of perfection.

If serious efforts are not undertaken soon, the disease will become unmanageable and a full-scale epidemic may break out during the 2012 monsoon. It will result in non-availability of agricultural and industrial labour, crippling the country and ruining its economy. We must understand the problem.

M. YUSUF BHATII Ex-malaria eradication worker Lahore