The monsoons are nearly here but there is no sign of the innovative measures, which corporation officials claimed to have up their sleeves to tackle the mosquito menace that worsens with the flooding and water stagnation that accompany heavy rain.

Some corporation officers claim that while they had successfully experimented with alternative methods to deal with mosquitoes, they are not in use on account of the pesticide lobby which objected to them, afraid of losing its place in the scheme of things.

The corporation gave in to the companies that currently sell several tonnes of pesticides to it as they bring with them the promise of hefty commissions for continued business, they allege.

“It’s big business. Such corrupt practices are rampant in the corporation,” claims opposition leader, K.J. Jacob, underlining that unless they are checked and the pesticide lobby shown the door, the fight against mosquitoes is unlikely to succeed.

Although the corporation usually de-silts canals, cleans the drains by fogging and flushing them with saline water as a pre-monsoon precaution, it hasn’t done as much this season, people complain.

But, chairperson of the works standing committee, Soumini Jain, strongly refutes the charges. “We’re ready to face the monsoon. Work is in progress as we’ve already released nearly `2 crore for cleaning in 74 divisions,” she says.

Mosquitoes outdo innovations

The city is known for its mosquito menace and the city corporation has, from time to time, initiated various projects to get rid of this threat — from conventional drain cleaning to bacterial spraying. But, what happened to all the innovative measures it took up?

One such innovative programme was to deposit guppy fish in the drains. This was undertaken as part of the Integrated Mosquito Control Programme (IMCP). The programme however, failed because the guppy is essentially a freshwater fish and therefore couldn’t survive in contaminated drains.
“You find that the oxygen supply is much less in a contaminated drain.

The method is, of course, cheap compared to using pesticides. But, it didn’t work in the city as the drains here are highly contaminated which leaves no oxygen for the fish”, said chairman town planning committee, K.J. Sohan.

The corporation also experimented with the spraying of bacterial larvicides which kill the mosquito larvae. Interestingly the city corporation was the first in the country to employ such a technique in its drive against mosquitoes.

Spraying was done for a few years and it was a huge success. But, the civic body discontinued its application as it had to face allegations of corruption in the purchase of 5,000-litres of bio-larvicide.

Last year, the corporation came up with another innovative idea — distributing nets and steel meshes to households so that they could close the air-vents to prevent the entry of mosquitoes. In total, the corporation purchased 50,000 nets to cover all the houses in the city.

“As of now, we’ve covered 50 per cent of the households. Some modern houses already have this facility. So, we’ll cover the rest which have no such facilities very soon,” health officer Dr C. Santha said.
The corporation now plans aerial fogging in the marshy areas of Vypeen and Puthuvypu which have become breeding grounds for mosquitoes. It’s seeking the assistance of the Vector Control Research Centre (VCRC) Pudhucherry for this.

Interestingly, it was VCRC that developed the bio-larvicide and formulated a master plan for mosquito eradication here.

Diseases commonly caused by mosquitoes

1 Chikungunya

A viral disease transmitted to humans by the bite of infected mosquitoes.

2 Filariasis

A mosquito-borne disease caused by tiny thread-like worms that live in the lymph system

3 Dengue

Prevention requires control or eradication of the mosquitoes carrying the virus that causes dengue.

4 Malaria

Malaria is an infectious disease caused by a parasite, Plasmodium, which infects red blood cells.

measures to keep mosquitoes away

1. Cover water tanks and wells
2. Deposit guppy fish in wells and lakes
3. Destroy discarded containers and egg-shells properly
4. Stop littering plastics
5. Keep the bathrooms and lavatory dry
6. Remove stagnated water in sunshades at
periodical intervals
7. Cover air-pockets and windows with nets