‘Prevailing weather likely to reduce dengue mosquitoes in city’

In the absence of much needed fumigation drives across the city, the only upside to the prevailing hot and dry weather could be eradication of mosquitoes especially those causing the dreaded dengue virus, according to Dr Arshad Azmi of the University of Karachi’s Department of Zoology.

“Today the temperature touched 41 degrees Celsius and is likely to be a degree higher in the coming days. Although it would get unbearable for city’s residents but it comes as a blessing in disguise,” Dr Azmi said.

He explained that it is difficult for the dengue mosquito – Aedes Aegypti – to survive in temperatures above 40 degrees Celsius. “If these weather conditions prevail for the next few days, a large number of these mosquitoes would die out.”

The haemorrhagic fever has so far claimed 11 lives in Karachi, majority of them in the month of September and first week of October. The city has become a favourable breeding ground for mosquitoes owing to its poor sanitation condition, observed the expert.

Where heaps of garbage spread across the city for past several months was not enough, accumulate of sewage and freshwater at various places did the rest of the damage. The city hospitals are daily being thronged by dengue and chikungunya (also caused by a mosquito) patients.

Dr Azmi explained that mosquitoes that cause malaria, however, have adapted to higher temperatures, but since extreme heat dries up stagnant water, mosquitoes would overall eventually die out.

“There is, however, an urgent need to improve sanitation conditions in the city, carry out extensive fumigation drives and remove garbage so that mosquitoes are unable to breed in the city at the rate at which they are currently growing,” the expert maintained.

The Pakistan Meteorological Department predicted a week-long spell of hot and dry weather in Karachi from past Saturday to Thursday. The change in weather has occurred as a low pressure area developed in the Indian West Coast that has suspended sea breeze. The low pressure is sucking in all the moisture from the air.

However, renowned microbiologist Dr Shahana Urooj Kazmi asserted that we can’t only rely on the weather alone to help us get rid of mosquitoes. Other drastic measures are required to eradicate the vector causing dengue and chikungunya as well as malaria, she said.

“There is an urgent need to carry out fumigation drives, spray larvacidal insecticides and improve sanitation conditions of the city,” said the microbiologist. Specialist in treating tropical diseases, Dr Zeeshan Ansari said prevention is the best option the city’s people have to avoid contracting these viruses.

He urged people to regularly use mosquito repellents, mosquito nets, wear long sleeve shirts. The expert also called for taking extraordinary precautionary measures for children and the elderly.

“If the municipal authorities have no regard for their responsibilities, it is the job of the citizens to take precautionary measures to protect themselves and their family members from these viruses,” he maintained.