Verily to release 20 million sterile male mosquitoes in Fresno

Verily, the life sciences division of Google’s parent company Alphabet has begun releasing bacteria infected male mosquitos in Fresno, California. The release is a part of the Debug Fresno project, a field study that aims to rid the central California county of Aedes aegypti mosquitoes. First arrived in the area in 2013, the mosquitos are known to spread the Zika virus, dengue and chikungunya.

Earlier this year, a woman contracted the first confirmed case of Zika in Fresno through sexual contact with a partner who had been travelling. Verily’s plan hopes to now wipe out this potential Zika-carrying mosquito population to prevent further infections.

According to media reports, the mosquitoes are not genetically-modified. The mosquitoes have been rendered essentially sterile by infection with a bacterium called Wolbachia pipientis, which naturally colonizes mosquitoes and other insects in the wild. The bacterium is considered harmless to humans. When these mosquitos mate with and infect their female counterparts, it makes their eggs unable to produce offspring. Bonus, male mosquitoes don’t bite, so Fresno residents won’t have to worry about itching more than they usually would.

Verily plans to release about 1 million mosquitoes a week over a 20-week period in two 300-acre neighborhoods in the Fresno area — the largest U.S. release to date of mosquitoes infected with the Wolbachia bacteria.