The West Nile virus has re-emerged in Orange County, with local officials now reporting positive tests among mosquito samples and the unfortunate discovery of an infected dead bird. The detection of the virus occurred in Anaheim and Garden Grove, alerting public health agencies to the potential risk at hand. According to NBC Los Angeles, this marks the first confirmation of West Nile virus within the county for this year.
The Orange County Mosquito and Vector Control District has captured mosquitoes in several neighborhoods, including those close by to Euclid Avenue and the 5 Freeway in Anaheim, and near Brookhurst Street and Garden Grove Boulevard in Garden Grove, that have tested positive. "Multiple mosquito samples and a dead bird testing positive for West Nile virus indicate that the virus is circulating in the community," Amber Semrow, Director of Scientific and Technical Services at OCMVCD, told The Orange County Register. No human cases have been reported in Orange County this year, however, with the warm summer weather ideal for mosquito breeding and transmission, the risk could escalate.
So far in California, cases of West Nile virus have been confirmed in Tulare, Stanislaus, and Kings counties. As the summer season progresses, the Orange County officials have begun implementing increased measures for mosquito surveillance and control, including the posting of warning signs in affected neighborhoods. In a public advisory, OCMVCD through a social media post emphasized the importance of area residents wearing mosquito repellent during peak activity times of dawn and dusk to mitigate the risks associated with this virus.
OCMVCD has confirmed mosquito samples testing positive for West Nile virus in the Cities of Anaheim and Garden Grove. Residents can take precautions by wearing mosquito repellent when mosquitoes are most active (dawn/dusk).
— OCMVCD (@OCVector) July 22, 2025
For more information visit- https://t.co/3w8voZwYRp pic.twitter.com/o1pMaOhwGo
Among the recommended precautions, officials are urging the public to eliminate any standing water where mosquitoes could breed, which includes residential features such as pet water bowls and bird baths. They also advise ensuring window screens are in good repair to prevent mosquitoes from entering homes. For those venturing outside during dawn or dusk when mosquitoes are most active, wearing long sleeves is also encouraged. "Dumping and draining standing water is the most effective and environmentally friendly way to rid mosquitoes from our communities," said OCMVCD Public Information Officer Brian Brannon, in a statement obtained by NBC Los Angeles.
The threat of the virus, which is spread primarily through the bite of an infected mosquito, remains a public health concern. While the Centers for Disease Control and Prevention note that most people infected with the West Nile virus will not exhibit symptoms, a fraction will develop more serious conditions, highlighting the critical nature of these preventative measures. As communities in Orange County face the reality of this year's West Nile presence, cooperation and vigilance remain essential in preventing its spread.
