Virus scare has experts going door to door, testing birds state
to state
By Verena Dobnick, Associated Press, 09/30/99
NEW YORK -- It's quite a scientific expedition -- testing
birds up and down the East Coast to track the encephalitis virus
that has killed five people and infected 38 others in the New York
City area.
"We've got to look at all kinds of urban birds -- crows, pigeons,
starlings and sparrows," said Andrew Spielman, an expert on
mosquito-borne diseases at the Harvard School of Public Health.
The West Nile strain of the virus has been found in dead crows in
the New York area. The U.S. Centers for Disease Control and
Prevention is now collecting blood samples from city pigeons and
also looking at ticks as possible carriers.
In New York's Queens borough, where the first cases of
encephalitis were reported last month, the CDC and the city's health
department planned to take blood samples door-to-door, with 300
households selected at random and on a voluntary basis.
"We hope to get a better understanding of the symptoms caused by
West Nile virus, as well as possible risk factors for infection,"
said Ned Hayes, the CDC's medical epidemiologist.
Fearing the infection might spread with the fall bird migration,
experts also are testing dead birds from Maryland to Florida. No
sign of the virus has appeared in those birds, said Roger Nasci, a
CDC entomologist.
The virus is believed to have been transmitted by mosquitoes that
typically feed off birds. Six new cases were confirmed Wednesday,
including a 79-year-old woman from the borough of Queens who died
Sept. 11.
New York, New Jersey and Connecticut have been spraying
pesticides to kill as many mosquitoes as possible before the first
winter chills.
Dr. Neal Cohen, the city's health commissioner, said mosquito
density has declined substantially, probably by 90 or 95 percent
since the second citywide spraying a few weeks ago.
The encephalitis cases found in New York originally were blamed
on the St. Louis strain. But late last month, some dead crows were
spotted near the Bronx Zoo. Subsequently, 20 zoo birds died and
tested positive for the African strain, said zoo spokeswoman Linda
Corcoran.
The West Nile virus -- never before recorded in the Western
Hemisphere -- probably entered the United States in infected
birds.
Symptoms of the strain -- fever and headache -- are similar to
those of the St. Louis strain but generally are milder. In rare
cases, the virus can cause neurological disorders and death. The
elderly, young and those with weakened immune systems are most
vulnerable.
