The Heat Is Online

West Nile Virus Seen Spreading Through Western Hemisphere


WASHINGTON, DC, July 6, 2000 (ENS) - West Nile virus, the bird carried disease that killed seven New York residents last year, may have now spread throughout North and South America, U.S. researchers warn. The U.S. Gulf Coast is considered the likely site for a new outbreak of the virus, reports "New Scientist" magazine.

"The virus is probably in every corner of North America by now" as well as parts of South America, said John Rappole of the Smithsonian Institution's zoo in Front Royal, Virginia. Another outbreak could occur anywhere there are enough infected birds, possibly this summer. "We think the next outbreak will be along the Gulf coast, where northern migrants remain concentrated." In the July issue of the journal "Emerging Infectious Diseases," Rappole and his colleagues report that 77 migratory bird species from the New York area are capable of carrying the virus from mosquito infested wetlands to areas throughout the Western hemisphere.

The scientists recommend monitoring of bird populations to identify high risk areas that could be sprayed with insecticide to kill the mosquitoes that transmit the virus to people. The infection is endemic to Africa, Asia and Europe, where it resides harmlessly in many bird species but kills others, said Bob McLean, head of the National Wildlife Health Center in Madison, Wisconsin. Humans usually get the disease from mosquito bites when the population of infected city birds is large enough to infect enough mosquitoes. By late last summer, the virus "had already infected more than half the local geese and sparrows. That's scary," said McLean.