NEW DELHI: A laboratory in Madurai is planning to release infected mosquitoes to cut the risk of dengue.
The Centre for Research in Medical Entomology (CRME), under the Indian Council of Medical Research (ICMR), is in the process of producing the bacteria-infested ‘strain’ of Aedes aegypti, which causes dengue.
The infected mosquitoes will eventually overpopulate the ordinary Aedes aegypti.
If successful, this will help find a solution to dengue and similar fevers which have been wreaking havoc in the country, according to official sources. The method has been considerably successful in Australia.
Scientists have planned to conduct meetings in Shillong and Rameswaram, two places with diversified ecosystems, for public opinion and awareness in about a year.
Meghalaya and other parts of the North East record high rate of mosquito-borne disease like dengue and malaria and if the experiment is successful, then the places will have a long-term solution to the health problems.
The Wolbachia bacteria, which are commonly found in many insect species like Culex but not in Aedes aegypti, are harmless to humans.
The University of Monash in Australia first found that Aedes aegypti infected with Wolbachia turns resistant to dengue virus.
A memorandum of understanding has been signed with Monash University for implementing the method in India.
When released into the environment, the Wolbachia-infected mosquito will infect the wild Aedes aegypti and experiments in Australia have shown that the number of dengue carriers came down.
The research is on at the Vector Control Research Centre in Puducherry.
If found to be adapting to Indian conditions, it will be tested in field experimental cage and released into the environment in a year, the sources said.
The field experimental cage will enable scientists to study how the modified and normal mosquitoes survive in an environment.
Producing a ‘strain’ of Wolbachia-infected Aedes aegypti involved making many micro injections.
If a thousand mosquito eggs were given micro injections of Wolbachia, only one may be infected which has to be developed into a strain of mosquito. In short, scientists will create a trans-species, which will not be a vector for dengue.
When the Wolbachia-infected female mosquitoes mated with males in the wild, they will produce a progeny with the Wolbachia.
An area into which the Wolbachia-infected Aedes aegypti is released will be monitored periodically.
If the number of infected mosquitoes is found to be less, a booster dose of a new batch of mosquitoes will be released into the area. The ambitious project — the field experimental cage to be established on an acre of land in Vadapalanji in Nagamalai Pudukottai in Madurai — is expected to be complete in a year at Rs 2 crore.
The project is a long-term one and the facility will include human habitations, artificial ponds, streams, grazing land and other aspects of a natural habitat enclosed in a dome of wire mesh.
It will also have a mosquito colony and microbiology facility.
The entrance to this facility will be protected by an air curtain to prevent the entry of mosquitoes from the outer environment.
Releasing the modified mosquitoes into the open environment was a policy decision and it will not be done without public opinion, the scientists said.
