By Dinesh C Sharma
Melbourne/New Delhi: It may sound strange but scientists are generating evidence to show that the solution to eliminating dengue lies in breeding mosquitoes that are incapable of transmitting dengue, and possibly chikungunya and even zika.
Several research groups globally are engaged in developing new vaccines, drugs and are even breeding genetically modified (GM) mosquitoes to combat dengue, but with little success. The approach developed by scientists at Monash University in Melbourne is radically different. It involves using a naturally occurring bacteria called Wolbachia which when present in Aedes aegypti mosquito reduces its ability to transmit dengue.
Wolbachia is rather ubiquitous bacteria – present in 60% of 5 million insect species, but strangely not in Aedes aegypti mosquito which harbours and transmits dengue virus. Scientists have transferred Wolbachia (extracted from fruit flies) into Aedes aegypti – not by any genetic engineering but by injecting it into to mosquito eggs and then breeding such mosquito lines. They have shown that Wolbachia-carrying mosquitoes don’t transmit dengue because the dengue virus can’t replicate itself due to Wolbachia. And if enough number of such mosquitoes multiply in the environment, dengue transmission in a given area can possibly be halted.
The approach has generated huge interest in dengue-endemic countries, including India.Earlier this year, the Indian Council of Medical Research (ICMR) signed an agreement with Monash University to work on the new approach in India.