California State Health Department Reports Number of WNV Infections in 2005 Surpasses Total for 2004

SACRAMENTO, Calif. --  The number of West Nile virus (WNV) human infections reported this year in California has surpassed last years total, according to interim state public health officer Dr. Howard Backer. California has recorded 832 West Nile virus (WNV) human infections so far this year, compared with a total of 830 last year.

"Although mosquito season is starting to slow down, recent mild temperatures mean that residents need to remain vigilant in protecting themselves and their loved ones from mosquito bites," Backer said. "West Nile virus was still being diagnosed in humans as late as Oct. 30 last year."

A total of 832 individuals from 39 counties have been diagnosed with WNV this year, surpassing 2004 by two infections and 16 counties. There have been 16 WNV-related deaths so far this year, compared with a total of 28 last year. Alpine, Del Norte, Sierra and Trinity are the only counties where the virus has not been reported.

Since July, California has provided $10.5 million to 80 local agencies to enhance and expand mosquito control across the state. The funding is part of the $12 million included in the state budget by Gov. Arnold Schwarzenegger to enhance resources of existing programs and to expand efforts in areas of the state not currently covered by mosquito control services. "Backer said, "Without this supplemental funding for mosquito control, Californians would have experienced much higher rates of illness and even death from West Nile virus."

The states interagency surveillance system for WNV continues to test dead birds, mosquito pools and sentinel chickens. A total of 2,747 dead birds in 52 counties have tested positive for WNV in 2005.

Most individuals who are infected with WNV will have no symptoms. Less than 1 percent of infected individuals will develop serious neurologic illness such as meningitis and encephalitis. The elderly and those with lowered immune systems are more susceptible to serious illness.

Source: California Department of Public Health