Google is seeking approval from U.S. authorities to release 32 million bacteria-treated mosquitoes in Florida and California, the move aims to combat the spread of mosquito-borne diseases.
The company plans to release as many as 16 million male mosquitoes per year for two years in both Florida and California.
The proposal is part of Google’s Debug initiative—launched in 2016—which aims to reduce the spread of mosquitoes by using a strain of Wolbachia pipientis bacteria in adult male mosquitoes to prevent them from reproducing.
The overall population declines when these males mate with wild female mosquitoes because the resulting eggs fail to hatch.
“We’re using an idea that’s been around since the 1950s. It’s called the Sterile Insect Technique (SIT), and it has worked on other kinds of bugs—like fruit flies, screwworms, and codling moths,” Debug said on its website. “The idea is simple: raise sterile males and release them into wild insect populations. When a wild female mates with a sterile male, her eggs won’t hatch. The population gets smaller with each generation.”
Mosquitoes, the world’s deadliest animal, transmit diseases like dengue, malaria, West Nile virus, chikungunya, yellow fever, and Zika.
Google’s initiative previously focused on Aedes aegypti, a mosquito species that transmits viruses such as dengue, Zika, yellow fever, and chikungunya. Its latest proposal targets Culex mosquitoes, the carriers of West Nile virus and St. Louis encephalitis, which are already circulating in California.
“Mosquitoes are fragile and difficult to rear in the necessary numbers,” it stated. “With Debug, we’re developing new technologies to make it possible.”
The U.S. Environmental Protection Agency acknowledged receipt of Google’s proposal in a notice published in the Federal Register in May, saying it “may be of regional and national significance”.
The agency said it was reviewing the request Google submitted in June 2025 and will decide whether to approve the experimental use permit after receiving public comments by June 5.
“EPA will decide whether to issue or deny the EUP request, and if issued, the conditions under which it is to be conducted,” the notice said. “Any issuance of an EUP will be announced in the Federal Register.”
Last year, the Florida Keys Mosquito Control District released Wolbachia-treated mosquitoes, a development that led to a significant drop in the mosquito population. The organisation will release more this year.
Success has been recorded using sterile insects to control the Mediterranean fruit fly and the New World screwworm, a fly whose larvae threaten livestock, wildlife, and pets.