Thermal fogging kills no mosquitoes, cool fogging kills all: Experiments with both conducted in Hyderabad

A demo of cold fogging was organised at Greater Hyderabad Municipal Corporation (GHMC) headquarters in Hyderabad on Tuesday (October 8, 2024).
| Photo Credit: By Arrangement

After decades of using thermal fogging as vector control method, and spending several hundreds of crores of rupees on diesel and petrol, the Greater Hyderabad Municipal Corporation officials have realised to their dismay that hardly any mosquito is dying with the chemical being used as part of the fogging operations.

An experimental use of fourth generation chemical for vector control at three locations of the city as part of a pilot has shown that the thermal fogging is not killing even a single mosquito.

No need for petrol or diesel

Named cool fogging, the method under observation uses a water based insecticide Deltamethrin instead of Malathion used in thermal fogging. The odourless chemical will do away with the need for petrol and diesel for mixing the chemical, thus resulting in huge savings for the corporation.

Experiment with mosquitoes in small cages and bed nets

As part of the experiments conducted at Kundanbagh and Prem Nagar, mosquitoes were captured in small cages and bed nets, and were subjected to both thermal fogging and cool fogging. With cool fogging all the mosquitoes died within half an hour, while thermal fogging resulted in no mortalities.

“Mosquitoes have been getting immune to the third generation chemical sprays, and adapting to the changing environment, so much that they are getting smaller in size too. In order to effectively purge them, we need a fourth generation solution. This is a proven chemical spray, approved by the World Health Organisation, cost effective and eco-friendly and eradicates mosquitoes effectively,” Additional Commissioner, Health, S.Pankaja informed.

A demo of the spray was organised for the Mayor G. Vijayalakshmi, Commissioner Amrapali Kata and other officials at the GHMC headquarters on Tuesday. On October 14, the same will be repeated for the standing committee members.

Proposal to govt after consultations with IICT

Consultations will be held with the Indian Institute of Chemical Technology for third party verification, after which the proposal will be sent to the government for approval, Ms.Pankaja said.

One more method under consideration is effecting genetic modifications in the mosquitoes so that they become incapable of reproduction, which is already being used in Singapore, she said.