Saturday , November 16 2024

Climate change is also responsible for the spread of diseases like dengue during monsoon, know how?

Dengue in Mumbai: There was a time when the monsoon would come and mosquito-borne diseases would spread. But now, due to climate change, mosquitoes do not have to wait for the monsoon to breed. Mosquitoes are able to spread diseases like malaria, chikungunya and dengue throughout the year. This year, from January to May, 92 cases of dengue have been reported in Vadodara alone. A large number of dengue cases have also been reported in cities like Ahmedabad and Anand. The situation is even worse in a metropolis like Mumbai.

Which mosquito causes dengue?

Humans are infected with the dengue virus through the bite of a female mosquito called 'Aedes aegypti'. Mosquitoes lay their eggs in waterlogged areas. The eggs hatch after ten days. The babies become adult mosquitoes and contribute to the dengue epidemic. The mosquito life cycle has four stages: egg-larva-pupa-adult, the first three of which occur in water, so it is important to eliminate them in water.

Earlier dengue used to spread only during monsoon, but now dengue is being seen even in non-monsoon season. There are many reasons for this.

Reasons for perennial dengue outbreaks

Due to changes in the environment in the last few years, mosquitoes are also changing their lifestyle. Mosquitoes that spread dengue and other similar viruses are now found throughout the year. Earlier, the rainy season used to come for four months. After that, there was no sign of rain throughout the year. For the last few years, there has been unseasonal rain in winter and summer, due to which water pits are filling up. If mosquitoes get even a little water, they lay eggs in it and start raising their family. Therefore, mosquito infestation is seen throughout the year.

Dengue has taken Mumbai hostage

Since the impact of dengue is more visible in the Mumbai metropolis, let us understand dengue in the context of that city. In the year 2023, 4400 cases of dengue were reported in Mumbai alone. Such a large number of dengue cases have not been reported anywhere in Maharashtra. By May 2024, the number of dengue cases in Mumbai has crossed 285. So then the question is why is there so much dengue in the metropolis?

The biggest problem of Mumbai, which has a population of more than two crore, is its population. Due to the dense population, mosquitoes have access to prey. Mosquitoes get breeding grounds due to reasons such as dirt in slums and water stagnation in open spaces. Tarpaulin is put on the roof of the house with a sheet or tube to prevent rainwater from entering the house during monsoon. The water that gets collected in it gives mosquitoes a chance to lay eggs. If that water dries up, the eggs remain alive and come out of the eggs when the water is filled again.

Like malaria, dengue is also a man-made epidemic. Urbanization without systematic planning also leads to an increase in mosquito-borne diseases. There are currently more than 60,000 construction projects going on in Mumbai alone. When a building is constructed, water is always required for its work. There is no one to check the condition of water stored in tanks, which drives away mosquitoes.

Mumbai's geographical location was also a factor. Situated very close to the sea, the city has a humid climate. Extreme heat during the day, coolness at night and rainfall in any season has led to diseases like dengue troubling Mumbai throughout the year. It is believed that mosquitoes breed in slums, but even residents of posh areas do not realize that places like flower pots kept in the balconies of their flats, plants planted in society gardens etc. are also home to mosquitoes.

What efforts are being made in Mumbai to control dengue?

There has been a steady increase in dengue cases across India, including Mumbai, in the last twenty years. The incidence of this case is particularly high in urban areas and densely populated areas. National Dengue Day is celebrated every year on 16 May by the 'Ministry of Health and Family Welfare'. Various programs are organized on that day to make people aware of dengue, but they are not enough.

The Public Health Department of Mumbai is doing remarkable and exemplary work in this regard. DDT is the most readily available weapon to control the spread of mosquitoes, but it is now losing its effectiveness. A new generation of mosquitoes, which have become thick-skinned after years of use of DDT, have developed immunity to it, due to which DDT is no longer able to control mosquito spread as effectively as before. New methods have been tried for this.

A Unique Weapon: Echo Bio Trap

A sachet (small bag) is placed in a medium-sized bucket made of cardboard. The vial is filled with an 'attractant' that 'invites' the female mosquito to lay eggs. As soon as the bucket is filled with water, the attractant starts working. The female mosquito comes and lays eggs in the bucket, but the eggs do not hatch due to the 'cidal ingredient' present in the bucket. The name of this mosquito killing device is Eco Bio Trap. One trap covers 400-450 square feet and lasts for a month.

The Mumbai Public Health Department has installed 38,000 traps in Dharavi and other slums. Considering that one trap lays about 1000-2000 eggs, this project will prevent the birth of crores of mosquitoes in Mumbai, which will ultimately prevent the spread of the disease. The Eco Bio Trap does not harm the environment as it is made of biodegradable material.

Conventional weapons are also being tested

To create awareness about the mosquito-borne disease, public health department staff in Mumbai go door-to-door to explain to people, take blood samples and test them so that the disease can be caught in the early stages. An app called 'Mumbai Against Dengue' was also launched in 2022, through which awareness is being spread among the people.

The number of reporting centres of the Public Health Department has increased from only 22 in 2023 to 880 by now, leading to more dengue cases but fewer deaths due to effective operation.