- The Washington Times - Tuesday, August 1, 2000

New reports of West Nile virus in New York have area health officials on the alert, with Virginia instituting a program that puts "test" chickens on the front lines and Maryland conducting tests on 120 dead birds.

Following reports of infected mosquitoes found in New York this year, Maryland officials said they continue to worry about the potential threat to the state since a single dead crow infected with the virus was found in Baltimore last December. It is the farthest from New York that the virus has been discovered since it first appeared in the country last year.

The virus also has surfaced in New Jersey, Connecticut and Massachusetts, where two crows tested positive last week.

Health officials in Massachusetts are trying to minimize public concern and are advising residents to use insect repellent, to wear socks, shoes and long-sleeved shirts, and to remove sources of standing water near their homes.

The virus, which killed seven persons in New York last year, is transmitted from birds to humans via mosquitoes. It can cause potentially fatal diseases like encephalitis or aseptic meningitis in 15 percent of the people infected.

There is no known cure for the virus, believed to have originated in Africa, nor method of treatment.

"We have many parts in Maryland with large mosquito populations," said Cyrus Lesser, chief of mosquito control in the Maryland Department of Agriculture. This year's wet weather is also a cause for concern because it creates conditions ideal for mosquitoes to breed, he said.

The testing of mosquitoes and birds, which started May 19, is being carried out by Maryland's Department of Health and Mental Hygiene using guidelines from the federal Centers for Disease Control and Prevention, Mr. Lesser said.

So far, none of the tests has turned up positive, said J.B. Hanson, a spokesman for the department.

One official said the virus could pose a greater threat to urban areas because of the kind of mosquito most likely to carry it.

The northern house mosquito, which breeds in gutters and water containers, is the kind that most often carries the virus, said Assistant Agriculture Secretary Charles Puffinberger.

Because this mosquito likes to breed in urban areas, "the Baltimore-Washington corridor is a good place to find it," Mr. Puffinberger said.

The health department is taking reports of dead birds on its hot line and has been collecting samples of dead birds that do not show obvious signs of trauma, like a bird that died by flying into a window, Mr. Hanson said.

The hot line, set up last year, has been receiving between 30 and 35 calls every day, said John Tugwell, a spokesman for the Department of Natural Resources. Callers usually respond to a questionnaire to determine whether or not the bird may qualify for West Nile virus testing, he said.

Birds that are being tested include crows, which are the most vulnerable to the virus, predatory birds like falcons and hawks, and blue jays.

Human surveillance is also being carried out rigorously, and hospitals are asked to report every case of encephalitis that comes in within 24 hours, Mr. Hanson said.

In most cases, the infected may simply show flulike symptoms, including fever, body ache, headache and sometimes a rash. More severe symptoms include high fever, neck stiffness, stupor, disorientation, coma, tremors, occasional convulsions and paralysis. More fatalities are likely to occur in those over 50.

In Virginia, state health officials hope 200 chickens will alert them to any signs of potentially deadly mosquito-borne viruses.

They have placed 20 groups of so-called sentinel chickens in the Tidewater region and are testing them every week or two for exposure to West Nile virus and three types of encephalitis including "Triple-E" or eastern equine, St. Louis and LaCrosse. Health officials say chickens don't die from the viruses, but get a mild infection. However, humans can die from two of the viruses. So far no signs of infection have been detected in the birds.

Results are not yet available on tests on crow and bluebird carcasses for West Nile virus. So far around 73 birds have been tested and several pools of mosquitoes have been studied, said David Gaines, public health entomologist with the Office of Epidemiology in Virginia.

In April, Virginia announced the formation of the Virginia Interagency Arbovirus Task Force, which will monitor for the virus in mosquitoes, birds, horses and humans.

In the District, 50 birds have been tested for the virus since April, when mosquito season started, said Ted Gordon, senior deputy director of public health assurance at the D.C. Department of Health.

The District is not yet conducting any tests on mosquitoes, nor is it spraying for mosquitoes yet. He said they would spray if any infections are reported. But the Department of Health has been working to control mosquitoes by inspecting catch basins and introducing larvicide to control mosquito larva, he said.

The department had also recently completed an agreement with the Army's entomology program for testing mosquitoes in case the virus turned up in the city, Mr. Gordon said.

"We're always concerned with any potential health risk," he said.

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