8th Case of West Nile Reported in State

West Nile virus has reached “epidemic conditions” in portions of San Bernardino County, state health officials said Wednesday, after eight human cases were reported in the county in June.

San Bernardino is the first county in California where the mosquito-borne virus has reached such levels, said Vicki Kramer, chief of the vector borne disease section of the state Department of Health Services. All eight of the state’s cases are in the county.

She cautioned that “epidemic conditions” describes a health-alert level meant to trigger aggressive actions by public health and insect control agencies, such as spraying residential neighborhoods with pesticides. She said it does not mean that hundreds of people have contracted the potentially deadly virus.

“We are just going by the standard definition of an epidemic, which is more cases than you would expect in a given place at a given time,” said Kramer. “This is a new disease in California. We are certainly very concerned about the West Nile virus activity documented today, and because of this concern and elevated risk, actions are being taken by San Bernardino County to reduce the risk.”

On Friday, county vector control crews will spray older, heavily vegetated residential neighborhoods in Fontana where six of the eight county cases have been documented. The spray, commercially known as Scourge, is safe for humans and pets when used in low levels and applied properly, officials said.

The spray is extremely effective at eradicating adult mosquitoes, such as the type that have been found carrying the disease in several parts of Southern California.

“It literally knocks the legs off of them,” said Joan Mulcare, manager of the San Bernardino County Vector Control division, “if it doesn’t kill them.”

At higher levels, insecticides of this type can cause problems in humans, including dizziness, headaches, nausea, muscle twitching, convulsions and loss of consciousness, according to the federal Agency for Toxic Substances and Disease Registry.

Proposals to spray Scourge or similar insecticides triggered protests in New York, Connecticut, Ohio, Illinois, Texas and Colorado.

John Roehrig, chief of the arbovirus diseases branch of the federal Centers for Disease Control in Colorado, said San Bernardino County officials were right to begin “adulticizing” -- targeting swarms of adult mosquitoes and not just mosquito larvae in standing water -- as soon as possible. Usually, local officials try to eliminate larvae first because of the public’s concerns about the spraying of pesticides, he said. San Bernardino officials are doing that as well and said adulticizing is a “last resort.”

“It’s not only a public health decision, but a political decision, and that’s the problem.... Many residents don’t like being sprayed,” Roehrig said. “There’s no evidence that there’s human risk.”

San Bernardino County officials said they’ve already launched an all-out effort to suppress the fast-spreading virus, including knocking on doors to test family members of reported victims and conducting helicopter surveys of neighborhoods to locate dirty swimming pools and other stagnant water.

“We are doing what we’re supposed to be doing at epidemic levels,” said Mulcare.

Because the virus is new to the state, human immune systems have not developed strong resistance to it, although only the elderly or those with seriously compromised immune systems are at risk of serious illness or death, Kramer said.

The virus is usually transmitted through a mosquito bite. The insects are infected when they feed on virus-carrying birds, which public health officials believe are spreading the disease across the country.

Officials have long predicted that West Nile would hit California hard this summer, as part of its spread across the Western United States. In recent months, hundreds of infected mosquitoes and birds have been found in urban areas of Southern California.

More than 260 people died nationwide last year, with Colorado the hardest hit. Nearly 10,000 people across the U.S. became ill, most of them with mild, flu-like symptoms.

This year in San Bernardino County, six of the reported cases have been in Fontana, including five members of the Rigby family.

Rob Rigby, 41, said most of his family contracted the virus sometime in May. His wife, Jackie, 40, remembered a mosquito bite she got while camping in Riverside County over Mother’s Day weekend. A week later she was covered in a rash and tortured by headaches.

A co-worker told her about a friend’s fiance who had died after feeling similar symptoms, so Jackie Rigby went to her doctor. A week later, she was diagnosed with West Nile, her husband said.

The state health department went to the Rigby house after Jackie Rigby told her doctor about her children’s ailments: lower back pain, rashes, aching joints. The department took blood tests and diagnosed her then-19-year-old son and 12-year-old twins with West Nile. Jackie Rigby’s mother, who lives in Nevada but visits often, was also tested and was found to be infected.

Rob Rigby said the family had no idea about West Nile when they first developed symptoms.

“We’re pretty well-educated about it now,” he said. “We’re a healthy family, so I’m not too concerned....”

Rigby said he and his daughter were the only two on the camping trip who escaped infection. Aside from his wife, who still gets the occasional headache, everyone has recovered.

Earlier this week, health officials said a 61-year-old Colton man was infected in late May or early June. Wednesday, officials said a 75-year-old Rialto woman had been hospitalized with aseptic meningitis after probably being bitten by an infected mosquito. She was reported to be stable.

“This weather is very comfortable for people, and it’s very comfortable for mosquitoes, too,” said Mulcare, of the San Bernardino Vector Control Program.

Kramer said California has an edge over other states in controlling the virus because of its extensive, highly coordinated statewide network of vector control districts.

But Roehrig, the CDC official, predicted that hundreds if not thousands of Californians will probably contract the disease this summer, most in mild form. He said some deaths would occur, too, particularly among elderly people or those with compromised immune systems.

“I think the chances are good for having a fairly large epidemic of West Nile virus in California,” Roehrig said.

Dr. Jonathan Fielding, director of the Los Angeles County Department of Health Services, said the county had no plans to fog or spray infected areas. “We have a relatively low adult mosquito count in L.A. County. There are no plans to do what they’re doing in San Bernardino County.”

He said there are small areas in the county where there are routine “adulticide” sprayings because those areas are hard to reach because of high weeds. “We don’t think there is a justification at this point for doing that in L.A. County, but we certainly do understand the reason for it in San Bernardino County.”

Both Los Angeles and San Bernardino counties will be posting warning signs about the virus in coming days.

In Fontana, on the streets where the spraying Friday will occur, signs are being posted advising residents to stay inside during the early morning spraying, to bring pets inside and to cover fish ponds.