The mosquitoes are engineered by the company MosquitoMate so that they deliver the bacterium to wild mosquitoes when released, killing off insects that could transmit viruses such as dengue, yellow fever and Zika.
Not only are mosquitoes annoying, but they can transmit a whole host of unsafe viruses. MosquitoMate will have a five-year license to sell in 20 different states and Washington, DC. These diseases are a large health threat and now the EPA has decided which direction they will take to reduce the threat. The eggs produced from the infected male and wild female mosquitoes will also be infected and won't hatch because the paternal chromosomes are infected with Wolbachia. The mosquitoes will be raised to contain the bacterium Wolbachia pipientis and the males are sorted out from the females. Trials have already been conducted in California and NY, which "demonstrated a greater than 80% reduction of the biting mosquito populations", according to MosquitoMate.
Only males will be released outside of the lab because they do not bite. As the number of released males increases, then the total population eventually declines. Image credits: Centers for Disease Control and Prevention's Public Health Image Library. Targeting the mosquito population of an entire city would require the weekly production of millions of the special mosquitoes.
Mosquitoes, though, are too fragile to blast with rays of radiation and still be capable of mating in the wild, forcing scientists to turn to other techniques such as genetic engineering or, in this case, the Wolbachia bacterium. The fact that it was able to conduct tests in the Keys is promising enough, considering a United Kingdom firm called Oxitec failed to secure permission to test its genetically modified moquitoes in the area. However, Florida has been hosting trials of the more-controversial genetically modified versions of the Zika vector, Aedes aegypti.
Most of the disease-carrying mosquitoes in the country are of a species called Asian tiger mosquitoes.