Danger Dust

While a mosquito bite is often no more than a temporary bother, in many parts of the world it can be scary. One mosquito species, Aedes aegypti, spreads the viruses that cause over 100,000,000 cases of dengue, yellow fever, Zika and other diseases every year. Another, Anopheles gambiae, spreads the parasite that causes malaria. The World Health Organization estimates that malaria alone causes more than 400,000 deaths every year. Indeed, their capacity to transmit disease has earned mosquitoes the title of deadliest animal.

Male mosquitoes are harmless, but females need blood for egg development. It's no surprise that there's over 100 years of rigorous research on how they find their hosts. Over that time, scientists have discovered there is no one single cue that these insects rely on. Instead, they integrate information from many different senses across various distances.

A team led by researchers at UC Santa Barbara has added another sense to the mosquito's documented repertoire: infrared detection. Infrared radiation from a source roughly the temperature of human skin doubled the insects' overall host-seeking behavior when combined with CO2 and human odor.