Mosquito repellents have been a popular form of personal pest-mitigation for several decades. Until recently, it was believed that DEET (and other repellent compounds) simply interact with odor-recognizing cells inside female mosquitoes and prevent them from landing and feeding. Dr. Jillian Stanford and researchers from Towson University and the Agricultural Research Service (ARS) in Beltsville, MD, have discovered an interesting physiological twist in the interaction between mosquitoes and repellents. By collaring yellow fever mosquitoes, Aedes agypti, the team was able to attach tiny sensors to the area of a mosquito's mouthparts that first contacts human skin, and record electrical impulses in response to different repellent compounds. By measuring and comparing cellular activity after exposure to salts, sugars, and repellents (including DEET, picaridin, and others), the scientists determined that at least three sensory cells within the mouthparts were stimulated, one for each of the tested 'tastes'. This could mean that a mosquito that was undeterred by smelling DEET, may land on someone and then decide against feeding, if the person's skin tastes like DEET.

The paper, titled, "Gustatory receptor neuron responds to DEET and other insect repellents in the yellow-fever mosquito, Aedes aegypti" was published in the journal Naturwissenschaften.