Contra Costa County vector control officials have confirmed the county's first case of a bird testing positive for the West Nile virus this year.
A stellar jay found in Pleasant Hill tested positive for the virus, the Contra Costa Mosquito and Vector Control District reported Thursday.
Finding a bird infected with the virus this early in the year could indicate a longer, more extreme West Nile season in the months to come, vector control district officials said.
Last year, the vector control district found its first bird of the season to be infected with the mosquito-borne virus on June 29.
"Mother Nature plays a significant role in virus risk," Craig Downs, the district's general manager, said in a statement.
"The mild winter has created a thriving environment for mosquitoes. We all need to be diligent about dumping out water where mosquitoes can live, such as rain gutters on houses, neglected swimming pools, boat covers, toys, even flower pot saucers can hold enough water to allow mosquitoes to thrive," Downs said.
West Nile virus affects the central nervous system and can carry serious symptoms including fever, aches, nausea, vomiting and sometimes a skin rash, according to the state Department of Public Health.
Those over 50 years old are at higher risk for developing serious symptoms.
To help avoid the virus, the vector control district recommends dumping standing water, using bug repellent and avoiding being outdoors when mosquitoes are present.
For more tips to guard against the disease, or to report neglected swimming pools where mosquitoes tend to breed, people can visit www.contracostamosquito.com.