Year’s First West Nile Cases Found

Two wild birds captured at a Fullerton park have tested positive for West Nile virus, marking the first cases in California this year and bringing an early -- and potentially dangerous -- start to mosquito season.

“It is earlier than I think a lot of folks had expected,” said Howard Sutter, spokesman for the Orange County Health Care Agency. West Nile virus, he said, “made its introduction in California last year, and the pattern across the country is that the second year typically is worse than the first.”

The health agency and the county’s Vector Control District, which discovered the virus in the birds, are urging residents to take basic precautions against mosquitoes, which can transmit the potentially fatal disease from birds to humans, horses and other animals.

“Our message to the public hasn’t changed,” said vector control spokesman Michael Hearst. “They need to be careful of breeding sources in the backyard. Anything that will hold water for a week can produce mosquitoes. When it’s as warm as it has been this past week, they can go from egg to mosquito in less than a week.”

Even the tray under a flowerpot can provide a breeding ground, he said. About half the county’s mosquitoes are probably bred in backyards.

Southland residents are also advised to use insect repellent, make sure screens are in good condition, and limit outdoor activity at dawn and dusk, when mosquitoes are most active.

Last year, at the end of the season, county officials trapped two birds that tested positive for the virus. Three dead birds also tested positive. Only one person tested positive for the virus in Orange County, but healthcare officials said it was not acquired locally.

The same year, however, a Riverside County resident came down with the disease after being bitten by a mosquito in Moreno Valley, where he worked on drains, sewers and other infrastructure surrounding the Santa Ana River. The man eventually recovered.

West Nile virus -- it usually causes no symptoms or mild ones, such as fever, headache and nausea -- first appeared in the United States in 1999, killing seven people in the New York area. Since then it has swept steadily west, causing 240 deaths nationwide last year.

About one in every 150 people infected with the virus develops a serious illness, whether meningitis or encephalitis. Orange County’s first probable victim was a 70-year-old man who spent two days at a Newport Beach hospital after coming down with the disease in 2002. That was after a visit to Central City, Neb., where he was believed to have been bitten by a mosquito. He made a full recovery.

There is no human vaccine for West Nile.

Two adult female house finches captured March 2 at Craig Regional Park in Fullerton tested positive for West Nile, Hearst said. The results have been retested and reconfirmed.