A mourning dove and red-tailed hawk found dead in Half Moon Bay early August tested positive for West Nile virus (WNV).
The mourning dove was picked up on Aug. 9, marking the San Mateo County Mosquito and Vector Control District's second bird to test positive for an acute WNV infection in San Mateo County in 2012.
The first bird to test positive for an acute WNV infection was a red-tailed hawk on June 11 in Woodside.
Additionally, a red-tailed hawk picked up on Aug. 10 in Half Moon Bay tested positive for a chronic infection of WNV.
Animals testing positive for a chronic infection are unlikely to have been infected recently, while an acute case indicates a recent infection. Because WNV is contracted from the bite of a virus- carrying mosquito, an acute case of WNV is more likely to mean that virus may still be circulating in the environment.
Vector control technicians are conducting extra mosquito monitoring in neighborhoods where positive birds and squirrels have been found to minimize the risk of contracting WNV. All mosquitoes trapped and tested in the county this year have been negative for the virus.
“This has been a hot season for West Nile virus across the state,“ said Angie Nakano, Acting Laboratory Director for the San Mateo County Mosquito and Vector Control District. “These virus-positive birds and squirrels are good reminders to avoid mosquito bites,” added Nakano.
The district recommends using mosquito repellent, as well as limiting outside activities at dawn and dusk, when mosquitoes bite most often. Dump out containers with standing water, and report neglected or abandoned swimming pools to the district at (650) 344-8592.
Fresh carcasses of birds or tree squirrels can be reported to the West Nile virus hotline, online at www.westnile.ca.gov or by phone at 877-WNV-BIRD (877-968-2473).
People can have a mild case of West Nile and not realize it. Mild symptoms, according to the Pennsylvania West Nile Virus Control Program, include:
- Body Aches
- Occasional Skin Rash
- Occasional Swollen Lymph Glands
More severe symptoms include:
- High Fever
- Neck Stiffness
- Muscle Weakness
For more information on West Nile virus and district services, visit www.smcmad.org.