The California Department of Public Health (CDPH) announced today the first confirmed death in California due to West Nile virus (WNV). The death occurred in San Luis Obispo County.
West Nile virus is transmitted to humans and animals by the bite of an infected mosquito. As of July 9, WNV has been detected in 45 dead birds from 6 counties and 177 mosquito samples from 13 counties.
West Nile virus is influenced by many factors, including climate, the number and types of birds and mosquitoes in an area, and the level of WNV immunity in birds. The risk of serious illness to most people is low. However, some individuals – less than one percent – can develop serious neurologic illnesses such as encephalitis or meningitis.