San Mateo County Spraying Pesticide to Head Off West Nile Virus

Bay City News

San Mateo County mosquito control officials sprayed for mosquitoes in a roughly square-mile section of East San Mateo Wednesday night to prevent the spread of West Nile virus.

Five dead birds that tested positive for West Nile virus were found in San Mateo in June and July, raising concern about the spread of the disease, according to the San Mateo County Mosquito and Vector Control District.

Two of the dead birds, both crows, were found in San Mateo on July 21 and 23. The other three were found in San Carlos, Portola Valley and Menlo Park.

The district also found mosquitoes carrying the virus in San Mateo on Friday.

The area around where the mosquitoes were found -- in the 94402 ZIP code -- was sprayed with a material identified as Zenivex E4 from trucks to try to stop the spread of the virus to humans, district officials said.

The fogging took place between 9 p.m. Wednesday and 5 a.m. Thursday.

The area sprayed is roughly bordered by East Fifth Avenue, state Highway 92, Shoreview Avenue, Palm Avenue, Concar Drive and Roberta Drive, according to the district.

The district will collect mosquitoes again once the fogging is complete. If West Nile is detected again, there may be more fogging.

West Nile virus is transmitted through mosquitoes and can be carried by birds, humans and horses. It is not transmissible from human to human.

Residents can help prevent the spread of the virus by using bug spray, eliminating standing water and calling the district if they notice mosquitoes.

The district also asks anyone who finds dead birds or squirrels to report them to www.westnile.ca.gov or by phone at 877-WNV-BIRD.