Male mosquitoes sometimes suck, too

Male mosquitoes also could be nearly as bloodthirsty as females under certain conditions, new research suggests. That upends the notion that simplest female mosquitoes bite, drink blood and spread diseases while males sip nectar.

The finding hints that males aren’t entirely innocuous and will play a tiny role in disease spread.

Male Culex tarsalis and Aedes aegypti mosquitoes, which are in general disinterested in blood, will take blood meals when humidity is low and so they'll’t get sugar, researchers report October eight in a preprint submitted to bioRxiv.org.

A graduate student in entomologist Jason Rasgon’s lab at Penn State noticed that some male mosquitoes would every so often feed on blood through a skinny synthetic membrane when researchers dropped the humidity and took away their usual nectar meals.

Rasgon desired to know if parched males would are trying and get blood from someone, so he stuck his hand in cages containing male mosquitoes. Hydrated males mostly now now not noted him, but dehydrated males would land and probe his skin. One even bit him. “It just barely got into the primary layer of the skin,” Rasgon says. “I transform taken aback [and] transform now now not anticipating that to happen.”

Male’s long tubelike mouth parts aren’t ready to piercing deeply enough to draw blood. But a scratch delivered by Rasgon’s cat, Jiji, allowed him to test whether males may maybe get blood differently. Sure enough, dehydrated male mosquitoes sipped blood from the open wound.

In a single more experiment, A. aegypti males genetically engineered to be unable to sense humidity didn’t take blood meals more often when humidity transform low. Those findings suggest that males may go for blood to slake their thirst.

One previous research paper indicated that blood is toxic to male Culex quinquefasciatus mosquitoes, and scientists thought all male mosquitoes lacked the ability to digest blood. But in Rasgon’s experiment, blood-fed male C. tarsalis mosquitoes lived goodbye as those who didn’t get blood, and even a smidge longer.

In nature, A. aegypti is the main carrier of yellow fever, but may maybe also spread Zika, chikungunya and dengue, while female C. tarsalis can spread West Nile, St. Louis encephalitis and related diseases (SN: eight/26/24; SN: 6/2/15). Male C. tarsalis mosquitoes also could be infected with West Nile virus and produce infectious virus in their saliva clone of females can, the researchers found.

Rasgon doubts males are important spreaders of disease, but scientists should reassess the basis that male mosquitoes don’t feed on blood and will to know about whether, in rare instances, males can provide the prospect to spread viruses.