West Nile virus is generally a risk from June through October. Mosquitoes become infected when they feed on infected birds and can transmit the virus to humans and animals through their bites. MPG file photo

YUBA-SUTTER, CA (MPG) - Yuba and Sutter counties have each confirmed their first human case of West Nile virus this year as mosquito control officials warn of increased virus activity and an elevated risk of infection across the region.

Sutter County Public Health confirmed its first case Aug. 17, three days after Yuba County Public Health announced its first case Aug. 14. The Yuba County patient was briefly hospitalized and has since recovered. Officials did not release additional information about either patient. 

The local cases come during an active West Nile season across Northern California. Neighboring Butte County reported its first West Nile-related death of the year Aug. 13. The individual was between 80 and 90 years old and died from complications related to the illness.

Statewide, the California Department of Public Health had reported 30 human cases, including three deaths, across 14 counties as of the end of last week, according to Sutter County Public Health. The number of human cases statewide was double the number reported at the same point last year.

"We continue to see increased virus activity and detections in our surveillance system. The risk for human infection is elevated," Sutter-Yuba Mosquito and Vector Control District Manager Stephen Abshier said. "Residents need to remain vigilant in protecting themselves from being bitten by mosquitoes."

West Nile virus is generally a risk from June through October. Mosquitoes become infected when they feed on infected birds and can transmit the virus to humans and animals through their bites.

"The best way to prevent West Nile Virus infection is to avoid mosquito bites," Sutter County interim Public Health Officer Dr. Gail Newel said. "Stay protected when outdoors by wearing long sleeves and long pants, especially at dawn and dusk, when mosquito activity is highest. Wear an effective mosquito repellent. And drain any areas of standing water where mosquitoes could breed."

Most people infected with West Nile virus do not develop symptoms. About one in five develop mild to moderate illness with symptoms that can include fever, fatigue and body aches. Fewer than one in 150 develop severe neurological illness, such as encephalitis or meningitis. Severe illness can result in lasting disability or death.

Officials recommend following the "Three Ds" to reduce the risk of infection: use an effective mosquito repellent such as DEET, take precautions during dawn and dusk when mosquitoes are most active and drain standing water where mosquitoes breed.

Residents should regularly check flowerpots, tires, rain gutters, pet bowls and other containers for standing water. Regular landscape irrigation can also create mosquito breeding areas. For water that cannot be drained, including fountains and ponds, officials recommend mosquito-control products or mosquitofish that feed on mosquito larvae.

The Sutter-Yuba Mosquito and Vector Control District will continue trapping mosquitoes for testing and treating areas with high West Nile activity using truck-mounted foggers. Residents can view planned spray areas and a surveillance map showing West Nile-positive dead birds, mosquito collections and sentinel chickens at http://sutter-yubamvcd.org.

Additional information about West Nile virus and statewide activity is available at westnile.ca.gov.