The Birds: A key to tracking West Nile virus

DELMAR, N.Y. - Dead birds are piling up at Ward Stone's door by the van load - a blue jay in a picnic cooler, frozen crows packed in dry ice, sparrows, hawks and warblers.

The birds are potentially infected with the deadly West Nile virus, and Stone, New York state's wildlife pathologist, will pluck some out for examination. Organs of sick-looking birds will then receive a final diagnosis at a lab nearby, where Dr. Laura Kramer and her staff are already inundated with hundreds of bird parts and thousands of mosquitoes.

This is how the West Nile virus is being tracked.

The mosquito-borne virus, which can cause encephalitis, a brain inflammation, killed seven people in the New York City area last year during its first known appearance in the United States and has become a public health threat this summer, too.

Three elderly New York City residents tested positive for the disease in the nation's only confirmed cases this summer. All three are recovering.

Most people who contract the disease experience flu-like symptoms. But the virus can be dangerous in children under 5, the elderly and people with compromised immune systems.

Given that threat, New York is among 44 states, along with the District of Columbia and New York City, getting funding from the Centers for Disease Control and Prevention for surveillance of mosquito-borne diseases.

Infected birds and mosquitoes can serve as an early warning system for the presence of the West Nile virus. So at the urging of New York health officials, counties and private citizens have been sending dead birds to Stone's wildlife pathology lab just outside Albany.

So far this summer, scores of infected birds have been found in New York, New Jersey, Connecticut, Massachusetts and Rhode Island, with nearly 300 in New York state alone, most of them crows discovered in the New York City area.

The findings have prompted insecticide spraying in New York City and other regions.

Analyzing the dead birds is a huge and exhausting job. Researchers at the New York state Health Department's West Nile virus lab, which Kramer heads, work weekends and the office is running out of space for specimen jars. Stone starts at 3 a.m. and puts in 16-hour days to keep up.

''I don't think I go five minutes in a day without thinking of West Nile,'' Stone said.

Stone and his small staff perform triage on the hundreds of bagged and boxed birds arriving daily. They must decide which birds to perform a necropsy on - fresh carcasses are better than old ones, crows are better indicators than some other birds.

Stone looks for West Nile symptoms such as lesions on the birds' hearts or enlarged livers and spleens. If he finds symptoms in a bird, four specimen jars are shipped to the state Health Department's nearby Griffin Lab - one jar each for a bird's brain, heart, spleen and kidney.

Kramer's staff, working in the tight confines of a converted horse stable, performs molecular tests on the tissue for a final diagnosis.

Kramer's lab receives about 200 birds a week. On top of that, tests are done each week on some 600 pools of mosquitoes shipped in on dry ice from around the state.

Kramer came out from California in May to head the lab and has been hustling to keep up since.

''I really am amazed at the level to which the virus has spread,'' Kramer said.

Other states have also kept busy. For instance, Connecticut has trapped and tested 104,000 mosquitoes. But New York is believed to be doing more testing than any other state.

Stone said the work may not let up until a little after Labor Day. With luck, disease-carrying mosquitoes will perish with the first frost. The would give Stone a chance to get back to his other pathology work, such as checking contaminated turtles and diseased ducks. Kramer wants to spend the winter researching West Nile research, instead of reacting to it.

And after that?

Theodore Andreadis, chief medical entomologist for Connecticut's Agricultural Experiment Station, offered this gloomy assessment: ''Next year, we're going to be doing this all over again.''

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On the Net:

New York State Health Department: http://www.health.state.ny.us/nysdoh/westnile/index.htm

Centers for Disease Control and Prevention: http://www.cdc.gov/ncidod/dvbid/westnile/index.htm