Mosquitoes are some of the deadliest creatures in the world, carrying diseases like Zika, dengue and chikungunya. In response, the U.S. government has given the green light to a unique strategy for ridding people’s yards of the disease-bearing pests.
In early November, the Environmental Protection Agency (EPA) granted commercial approval for the company MosquitoMate to release its special male Aedes albopictus mosquitoes, called ZAP mosquitoes, in 20 states and Washington DC. The company’s approach uses a type of bacteria called Wolbachia, which certain types of mosquitoes naturally carry. MosquitoMate has developed the ability to breed two types of mosquitoes that often carry diseases—Aedes albopictus and Aedes aegypti—that carry a different form of the bacteria that’s incompatible with the Wolbachia carried by their wild mosquito counterparts.
When MosquitoMate releases their ZAP male mosquitoes into the environment, the mosquitoes mate with wild females and pass on their Wolbachia to their offspring. Those offspring never actually hatch, however, because the Wolbachia interferes with the mosquitoes’ parental chromosomes, causing the the eggs to not develop.
They only release males, because male mosquitoes do not bite people.
So far, MosquitoMate trials in Kentucky, California and New York have shown that the ZAP mosquitoes can reduce the overall mosquito population of a given release area by more than 80%.
Stephen Dobson, the CEO of MosquitoMate and a professor and medical entomologist at the University of Kentucky, says he’s been working on the Wolbachia-carrying mosquitoes for about 20 years.
“A ‘self-delivering’ mosquito control approach is more effective than traditional methods that rely on people to find cryptic mosquito breeding spots,” says Dobson. He adds that the increase in invasive mosquito species, and the fact that mosquitoes are becoming resistant to existing pesticides, increases consumer desire for more effective ways to get rid of them. That this approach does not use chemicals like pesticides is also appealing, he says. MosquitoMate’s mosquitoes are also not genetically modified.
The Wolbachia approach has been used by other groups in Brazil and Australia. Another company called Oxitec also uses a live mosquito approach. Their male mosquitoes pass on a deadly gene to their offspring that kills them before they reach adulthood. Oxitec is also in discussions with the EPA for releases in the U.S.
The EPA has given commercial approval for MosquitoMates’s Aedes albopictus ZAP mosquitoes for five years. Dobson says it also has an experimental use permit for the company’s Aedes aegypti mosquitoes. The company plans to start selling the ZAP mosquitoes commercially to individuals or businesses like hotels in the spring, when mosquito season starts to kick off.