Officials coordinate West Nile virus strategy

Tuesday, April 27, 2004 | 9:15 a.m.

Nevada and Clark County health officials are bracing for the West Nile virus to hit the state for the first time this summer, and health agencies are pooling their efforts to face it.

The Clark County Health District is leading the way with a $23,000 grant from the Nevada State Health Division for West Nile virus surveillance. Clark County vector control received another $7,000 for mosquito control.

If West Nile surfaces this summer, officials said they will try to wipe out infected mosquito populations.

County vector control monitors and eradicates mosquitos along with the Nevada Department of Agriculture.

"First and foremost we don't want people to be afraid," said Vivek Raman, an environmental health specialist with the health district. "This year we're going to have a more collaborative approach to this."

Health officials plan to place chickens as sentinels in areas of the Las Vegas Valley where mosquitos that might carry West Nile virus gather, Raman said. The chickens will then be tested every two weeks.

"That way we can look at whether these chickens have been infected with West Nile," Raman said.

Mosquito surveillance will include trapping insects to see which species are here and also how many are in the valley. A couple of migrating birds were discovered in Southern Nevada carrying Western equine encephalitis, but the virus has not been found in mosquito pools tested, Raman said.

This year the blood tests will be examined for West Nile, Western equine encephalitis and St. Louis encephalitis, Raman said.

The U.S Division of Wildlife Services relocates migratory birds from local watercourses at hotels and golf courses and places them in the wild.

In terms of monitoring, officials will watch ravens, magpies, owls and hawks this year in Southern Nevada. Those birds get infected with the West Nile virus most frequently, Raman.

Also participating are health and mosquito control districts in Washoe, Clark, Churchill and Douglas counties, and in Carson City and Mason Valley. The state is coordinating mosquito controls in other rural counties.

Nevada's 40,000 registered horses will be checked annually for the West Nile virus.

Last year Colorado was the state hardest hit by the virus. A total of 2,974 people became ill and 61 died, the Centers for Disease Control and Prevention said.

Nationwide a total of 9,858 people were diagnosed with health problems connected to the virus in 2003, and 262 died.

Two Nevadans were reported infected with the West Nile virus last year, but both contracted the disease out of state, health officials said.

West Nile virus first surfaced in New York in 1999. Since then, only Nevada and Oregon have escaped the infection.

West Nile virus is carried by infected birds. Mosquitoes that bite those birds draw the virus through the blood, then can transmit it to other birds, animals and people.

Most infected people show no symptoms. In most the disease is mild and flu-like, but in rare cases, the brain can swell and lead to death.

Experts expected the virus to reach Nevada last summer, but it didn't. Officials speculate that the drought conditions limited mosquito populations.

The virus has emerged in people, birds, mosquitoes and horses in neighboring Utah and Arizona. Virus-infected birds and mosquitoes were also discovered in San Bernardino, Calif.