KARACHI, Sept 20: While the City District Government Karachi (CDGK) is starting the next round of anti-dengue fumigation drive on Wednesday, the official concerned has urged people to help make the campaign a success by ensuring that no water is accumulated around their houses as this becomes a breeding ground for mosquitoes.

CDGK official Dr Shaukat Zaman told Dawn on Tuesday that although the poisonous chemical being used in the fumigation drive was recommended by the World Health Organisation (WHO), coming in contact with it should be avoided as this could cause irritation of skin as well as eye and respiratory track problems.

He said that a dengue virus control room with telephone number 021-99230820 had been set up at the Civic Centre where people could report dengue cases/patients.

After receiving the report, a team would be dispatched to the house of the patients to fumigate the entire vicinity with Deltamethrin insecticide — being used by the CDGK for the first time.

He said that Deltametrin and Permethrin were being sprayed by CDGK workers using vehicle-mounted fogging machines. The government had provided 8,000 litres of insecticides for the purpose, he said, adding that 40 vehicles, with four CDGK workers each, were employed in the fumigation drive. They were carrying out fumigation early in the morning and then in the evening — the timings during which ‘Aedes aegypty’, the mosquito species that spreads dengue, comes out to feed and in the process also stings people.

Dr Zaman said that 20 vehicles were sent to one town in the morning and another town in the evening. “In this way, four towns are fumigated every day in order to cover the entire city in less than a week,” he explained.

The official said that this cycle would continue at least till the end of November after which the weather would turn chilly and mosquitoes, which could not survive extreme cold or hot weather, would die a natural death.

Besides fumigation that kills adult mosquitoes, CDGK workers are also carrying out cleaning and de-grassing of the storm-water drains in the mosquitoes anti-egg and anti-larvae operations. These drains are in bad shape as sewage that carries sludge etc is also drained in many of these channels.

Dr Zaman pointed out that many drains had been covered and structures like markets, offices, commercial concerns, etc had been built over them. Encroachments including houses that had been constructed and leased out over these drains had narrowed down the natural waterway, he added.

These structures hampered the cleaning exercise owing to which many of the drains remained choked or blocked and the entire area around them submerged during rains, he argued.

The official said that the CDGK was also planning to launch an awareness campaign in government schools so that students could be sensitised on hygiene and they in turn could spread the awareness among their parents, relatives and friends telling them not to avoid stagnant water around their houses and also to keep water always in properly covered containers at home. Private schools would also be asked to join in the campaign, which would be monitored by the officials concerned, he added.

While the current extensive anti-dengue fumigation activity would come to an end after a couple of months, the routine fumigation would be continued round the year, except in peak winter and peak summer, he said.

Meanwhile, an environment expert, F. H. Mughal, told Dawn that owing to the adverse effects of the chemicals on human health, people should be informed of the scheduled fumigation in their respective areas in advance so that they remained indoors and took precautions, besides covering eatables, fruit, vegetables, drinking water, etc.

Depending on the severity of exposure, the insecticides could cause skin, eye and respiratory track problems and, in some cases, dizziness. Extreme exposure could even prove fatal, he added.

Mr Mughal said that effect of the chemicals on the environment was local as they would dilute in the air. It must be ensured that a drinking water source was not infected with the chemical, he said, adding that mosquitoes liked moist spaces where they could comfortably breed.