More virus cases expected

Friday, July 23, 2004 | 11:31 a.m.

After two Nevada residents were identified as possibly suffering from West Nile virus, just three days after state officials confirmed its existence in a bird and mosquitoes in Northern Nevada, health officials fear they will find more cases.

As a result, efforts to monitor, test and eradicate mosquitoes are being stepped up locally. In Southern Nevada the biggest swarms of the insects appear near the Las Vegas Wash and its tributaries.

Most Las Vegas residents had not heard Thursday night about the two West Nile virus cases in people.

Mike Jilgan, 26, and a native of Las Vegas said he had never noticed mosquitoes in town. "I've had a problem at Lake Mead and on the Colorado River," he said, noting he takes a week every year to kayak on the lake and river.

Copeland Sports store manager Keith Guy said he had not noticed an increase in the sale of insect repellent.

"We've had people going overseas, wanting DEET," Guy said after learning about the virus in Nevada. "I'm sure we will be moving our product up front."

Longs Drugs pharmacist Anne Hartig, of upstate New York, said all she had heard about was the West Nile virus in birds.

"We haven't had anybody ask about it yet," Hartig said, although she was well aware of the virus.

If tests confirm that a Southern Nevada resident does have West Nile, the person, whom health officials would not identify, would be the first to contract the disease within the state, health officials said Thursday.

Dr. Donald Kwalick, chief health officer for Clark County, announced the potential West Nile virus case during a board meeting on Thursday morning. The federal Centers for Disease Control and Prevention in Atlanta is conducting laboratory tests to confirm the virus with results expected in about a week.

The patient, described as younger than 50, had preliminary tests indicating that it was West Nile virus with symptoms of meningitis, an inflammation of the tissues that cover the brain and spinal cord.

The affected person had traveled to Nye County for a camping trip over the July Fourth weekend.

"The incubation period fit for the virus developing after the camping trip," Clark County Health District spokeswoman Jennifer Sizemore said.

Once a mosquito bites a person, it takes from three to 14 days for symptoms to appear, Sizemore said. While most West Nile virus victims won't know they have the virus because no symptoms appear, about 20 percent of those infected develop flu-like symptoms called West Nile fever, she said.

In some cases, 1 in 150 on average, more serious complications develop, including meningitis and encephalitis, or an inflammation of the brain.

The Southern Nevada patient, who had been hospitalized, is recovering at home, health officials said.

A Reno patient, also younger than 50, developed an illness earlier this month, then was hospitalized with meningitis and has since fully recovered. Preliminary tests conducted in Nevada and California indicate the illness was associated with West Nile virus, which affects the central nervous system, state epidemelologist Randy Todd said.

Nevada's detection of the virus and then the report of two human cases indicates how quickly it can spread from bird to human.

Clark County Vector Department is expanding its mosquito monitoring, entomologist Richard Hinks said. Results were not available yet from mosquitoes and birds sent to the state laboratory, he said.

"This thing starts to roll and then it snowballs," Todd said. "I hope we don't have seriously ill people."

Washoe County health officials are unable to pinpoint where the Northern Nevada patient contracted the illness, Todd said.

People who develop flu-like symptoms in the summer should stand out to physicians.

"This is not flu season, so these symptoms are unusual," Todd said. "Those people may have West Nile fever."

Those older than 50 are most at risk to suffer from a more severe form of the disease, Todd said.

Precautions people should take if they are outdoors at dawn or dusk include wearing insect repellent with DEET in it, long-sleeve shirts and long pants to protect from mosquito bites, he said.

Homeowners need to remove any standing water in their yards. Mosquitoes breed in still, shallow water.

"A coffee can left for several days with water in it can become a breeding site," Todd said. Even swamp coolers can create enough of a puddle underneath to offer mosquitoes breeding grounds.

Dead or ill birds, especially crows, ravens and magpies, should be reported to local authorities, Todd said. In Clark County the phone number to make a report is 383-1251.

Birds of prey such as eagles, hawks, falcons or owls are also considered to be reservoirs for the virus, Todd said.

"Those birds are a high priority for testing if someone sees them sick or recently dead," Todd said.

Birds dead less than 24 hours can better be tested for West Nile virus than those that are stiff or decaying.

Nevada officials had expected to see West Nile virus last summer, Todd said.

"Fortunately, we got a one-year reprieve," he said.

The West Nile virus first appeared in the United States in New York during 1999 and has been spreading westward. It has killed more than 560 people in the past five years. The disease has sickened nearly 200 people across the country so far this year, the CDC said.

California health officials announced the death of an Orange County man from West Nile virus on Thursday, the first human fatality in the Golden State from the illness.

The 57-year-old man died June 24 and was believed to have contracted the virus in Orange County, said Robert Miller, a spokesman for the California Department of Health Services. The cause of death was confirmed Wednesday.

There have been 35 human cases of West Nile virus reported in California this year.