Scientists wean mosquitoes off blood with dieting drugs

By Dr. Ananya Mandal, MDFeb 7 2019

Researchers have found a way to reduce the blood thirst of mosquitoes and prevent mosquito bites and spread of mosquito borne illnesses such as Zika, dengue fever, malaria and chikungunya. The results of their findings in a study titled, “Small-Molecule Agonists of Ae. aegypti Neuropeptide Y Receptor Block Mosquito Biting,” have been reported in the latest issue of the journal Cell.

Aedes aegypti mosquito on human skin. Image Credit: khlungcenter / Shutterstock

The team from Rockefeller University in New York City has developed means by which the mosquitoes would feel too full to bite. Still at preliminary stages of their research, the team says that they used Aedes aegypti mosquitoes for their study. They explain that the females of these species are attracted to human blood because they need a protein from human blood for producing their eggs. When fed on blood, these mosquitoes may not take another blood meal in days, they explain.

For their experiment, the team fed these female mosquitoes a saline solution containing diet drugs used in humans. They found that the mosquitoes promptly lost their appetites after having fed on diet drugs. They even used a piece of a nylon stocking with the body odour of study author Laura Duvall, a postdoctoral fellow at Rockefeller University to lure the mosquitoes. The insects were still not interested.

Next up the team looked at the neuropeptide receptors of the mosquitoes and found that one of the drugs was numbing their receptors and making them unresponsive to the odours. With this knowledge the team could next learn where this neuropeptie reseptors lay and how they could be controlled to get the mosquitoes off human blood. Senior author Leslie Vosshall, head of the laboratory of neurogenetics and behaviour at Rockefeller University said, “We're starting to run out of ideas for ways to deal with insects that spread diseases, and this is a completely new way to think about insect control. Insecticides are failing because of resistance, we haven't come up with a way to make better repellents, and we don't yet have vaccines that work well enough against most mosquito-borne diseases to be useful.”

Researcher Ms Duvall, said that this was a great idea to focus on the appetites of the mosquitoes. She said that this would not eliminate the mosquitoes but their diet might be controlled. She said, “We are multiple steps away from using this in the field, and we will always need other complementary strategies alongside this.” She speculated they might use traps for mosquitoes laced with these drugs to stop them from biting.

Authors conclude that they, “...show that these drugs can inhibit biting and blood-feeding on a live host, suggesting a novel approach to control infectious disease transmission by controlling mosquito behaviour,” adding that this study may “have broad applications across blood-feeding arthropods that spread disease to hundreds of millions of people each year.”