Mosquitoes testing positive for West Nile virus were discovered in Anaheim and Garden Grove, the Orange County Mosquito and Vector Control District reports.

There have been three human cases of West Nile Virus in California this year, with one fatal case, according to the California Department of Public Health.

The Mosquito Control Division of the city of Aberdeen has identified West Nile virus as well as an increasing population of the Culex Tarsalis species, which is identified as one of the most common carriers of the virus.