SMART NEWS

How Mosquitoes Are Out-Smarting Humans

Mosquitoes have figured us out and have started biting during the daytime

Contributor

October 4, 2012

Mosquitoes. We all hate them. That buzzing, biting, itchiness-inducing insect is not only super annoying but also super dangerous. Mosquitoes transmit malaria, West Nile virus, dengue fever, Rift Valley fever, yellow fever and various forms of infections that cause brain inflammation. Fun.

If you live in an area with a lot of malaria-carrying mosquitoes, you probably sleep under a mosquito net. Since mosquitos are nocturnal, this simple technology keeps people safe from the bugs snacking on them in the night. But not any longer. Mosquitoes have figured us out and have started biting during the daytime.

A recent study in the Journal of Infectious Diseases suggests that mosquitoes are no longer sticking to their night time feasts. They’re biting in the early morning now.

Bora Zivkovic at A Blog Around the Clock explains how they did the study:

They collected mosquitoes in large numbers and recorded the time of day they caught mosquitoes. In addition, they used morphology to identify the genus, and PCR to identify the species. Every single mosquito was Anopheles funestus. They tested the caught mosquitoes for pyrethrin resistance and did not detect any – every single mosquito died. Thus all the changes were strictly behavioral.

And what they found:

During the period of just a few years as the bed nets got implemented in the two villages, local mosquitoes dramatically shifted the timing of activity. Instead of 2 or 3am, they now predominantly bit humans around 5am.

Uh oh. Of course, it’s not as simple as: mosquito bites earlier, everyone dies of malaria. There are lots of factors here, including the animals that feed on those mosquitoes, and the behavior of the humans the mosquitoes feed on. Chances are there will be downsides to this new early morning strategy. But if more people are being bitten by mosquitoes because they’re not protected by the netting, that’s probably a bad thing.