NEW YORK (AP) -- A strain of encephalitis never before reported

in the United States is to blame for at least one of three deaths

in the city, federal health officials said.

Researchers at the Centers for Disease Control and Protection

identified a "West Nile-like" virus in the victim on Friday and

were continuing to determine the specific strain, CDC spokeswoman

Barbara Reynolds said.

"We're using the word 'like' to indicate that we still have

some more work to do to determine if it is a variation on the

strain of West Nile or a new virus," she said.

Health officials said last week that a virus believed to be West

Nile had been found in dead birds in the metropolitan region.

Reynolds said the West Nile virus is usually found in Africa and

Europe, never before in the United States.

Scientists earlier thought St. Louis encephalitis killed three

and sickened 15 other people in the city and neighboring

Westchester County.

It's possible the numbers could go higher. Spinal fluid samples

from 77 people who fell ill but tested negative for St. Louis

encephalitis would be re-examined for the West Nile or Kunjin

virus, city Health Commissioner Dr. Neal Cohen told The New York

Times. Seven of those 77 people died.

Officials said the unprecedented discovery of the virus in the

United States was no cause for alarm, since the pesticide spraying

now under way to combat St. Louis encephalitis should also work

against the mosquitoes that carry the West Nile virus.

Brain tissue from victims of the encephalitis outbreak has been

undergoing analysis at the CDC and at the Emerging Diseases

Laboratory at the University of California at Irvine.

W. Ian Lipkin, the director of the Irvine lab, said his

colleagues had identified either West Nile virus or a variant found

in Australia, Kunjin virus, in the brains of three encephalitis

victims from the city's Queens borough.

"The significance of this is that this particular agent has

never been reported in North America," Lipkin said Sunday.