The Indian Express (Delhi Edition)
HORMONES CONTROL MOSQUITOES’ ATTRACTION TO BLOOD: STUDY
A NEW study has suggested that a pair of mosquito hormones work in tandem to activate or suppress the insects’ cravings for blood.
Female mosquitoes consume animal blood in order to develop their eggs. But after their meal, they lose their appetite till such time they lay their eggs.
Entomologist Michael Strand, of the University of Georgia in Athens, studied what controls this cycle. He, and his colleagues, found that the levels of a mosquito gut hormone called F(NPF) spiked when the creatures were looking for a host, and dropped once they were done feasting. NPF levels also closely mirrored mosquitoes’ interest in humans.
Another gut hormone, Ryamide, was found to work in the opposite way. As NPF levels fell down after a blood meal, Ryamide levels went up, and vice versa. The researchers thus surmised that NPF and Ryamide work together to stimulate and suppress mosquitoes’ attraction to humans and other hosts.
Mosquitoes are the deadliest animal on the planet. They act as vectors for diseases such as malaria, dengue, West Nile virus, yellow fever, Zika, chikungunya, and lymphatic filariasis, which together kill around 700,000 people in the world. The mosquito menace is getting worse with climate change, as mosquitoes can now survive in places that were hitherto too cold for them.
The recent discovery will aid scientists’ effort to fight mosquitoes. “The discovery could provide new pesticide targets for preventing mosquito reproduction and disease transmission,” Zhen Zou, an entomologist at the Chinese Academy of Science’s Institute of Zoology in Beijing, told nature.com.