Bug Blog

Do DEET Bug Off Sprays work on Mosquitos?

Mosquito Immunity to DEET

Mosquitos have been making mincemeat of U.S. citizens this year, spreading potentially fatal diseases through their itchy bite. Spray insect repellents are pretty much our best defense against their terror, but new research tells a different tale. Scientists have discovered that certain mosquitos can develop a tolerance for DEET, desensitizing them to the repellent.

Some mosquitos carry a special genetic code for their smell receptors that gives them the ability to simply ignore the smell of DEET. That news is bad enough, but now scientists have found that other mosquitos can undergo a short-term change that desensitizes them to DEET rather than a genetic adaptation. Scientists did studies on the Aedes aegytpi mosquito species, which carry dengue fever, and found that they undergo a short-term change as soon as they come in contact with DEET that allows them to stomach is for a good three hours. These mosquitos were unaffected by the DEET smell and still attracted to the heat and scent of human skin. The scientists think that these mosquitos have built up this immunity through regular exposure to repellents. They claim it is similar to the way a human’s sense of smell can adapt to a certain odor after prolonged periods of exposure.

Does this news scare you? What do you think the next step to take against mosquitos is if insect repellents begin being ineffective?