Two Northern California counties report human West Nile cases. Both people severely ill
Health officials in Northern California’s Yuba-Sutter bi-county region recently detected a human case of West Nile virus in each county, their first such cases of 2022.
Both are “experiencing severe illness,” county health officials and the Sutter-Yuba Mosquito and Vector Control District said Friday in a joint news release.
“We continue to see ongoing virus activity and detections in our surveillance system,” district manager Stephen Ashbier said in a prepared statement.
“The risk for human infection is high.”
The bi-county region first detected West Nile virus activity in late June, in mosquito samples.
The Sacramento region detected its first human case of the virus this year, in a Yolo County resident who became ill in July following a mosquito bite.
Severe illness from West Nile virus is rare, officials said in Friday’s news release, affecting only about one in 150 people who become infected.
Symptoms of severe West Nile in humans include neurological conditions such as encephalitis and meningitis.
Mild or moderate symptoms include fever and fatigue. About 80% of human West Nile cases are asymptomatic.
“The best way to prevent West Nile virus infection is to avoid mosquito bites,” Dr. Phuong Luu, health officer for Sutter and Yuba counties, said in a statement. “We want to remind everyone to stay protected by wearing long pants and long sleeves, especially at dawn.”
Residents are also urged to drain standing water on their properties. They may also consider using insect repellent.
West Nile virus activity is highest from June through October.
Officials said Sutter County has now detected West Nile virus in one human, four dead birds, 31 mosquito samples and nine chickens this year. Yuba County has detected it in one human, one dead bird, 12 mosquito samples and nine chickens.
California confirmed 129 human cases and 12 deaths from West Nile virus in 2021, officials said.
