West Nile's North American spread described

November 3, 2008

The rapid spread of West Nile virus in North America over the past decade is likely to have long-lasting ecological consequences throughout the continent, according to an article in the November issue of BioScience. The mosquito-borne virus, which was little known before its emergence in New York in 1999, has since been found in all 48 contiguous states.

West Nile virus has killed hundreds of millions of birds and more than 1000 people in North America, and new outbreaks occur each year. Horses are also commonly infected. Though populations of house wrens and blue jays have returned to normal levels, most of the bird species that suffered large population declines, such as the American crow, American robin, Eastern bluebird, and Tufted titmouse, have yet to recover. The extent of mortality in birds of prey and other affected animals remains largely unknown. Changes in seed dispersal, insect abundances, and scavenging services resulting from the virus's effects on wildlife "are probable and demand attention," according the article's authors, Shannon L. LaDeau of the Smithsonian Migratory Bird Center in Washington, DC, and three others.

LaDeau and colleagues emphasize that research has yet to provide a clear picture of why species vary in their vulnerability to infection by the virus and in their probability of transmitting it, via mosquitoes, to other animals. For humans, living close to vegetation cover within a city appears to increase the risk of infection, but scientists still have much to learn about how temperature, precipitation, and changing landscapes interact in fostering outbreaks. Research on how these factors affect susceptible wildlife and mosquitoes could lead to better predictions and possibly public warnings and expanded mosquito abatement programs in vulnerable areas.

Source: American Institute of Biological Sciences

Explore further: Determining America's most lethal animal

Related Stories

Determining America's most lethal animal

August 13, 2015

Animal attacks have been in the news a lot. Late last year, a 22-year-old student in New Jersey was killed by a black bear he had been photographing. This summer, swimmers off the coast of North Carolina have suffered a record ...

US turns to rewards in hunt for overseas cyber criminals

March 19, 2015

The FBI considers Evgeniy Bogachev one of the world's most prolific and brilliant cyber criminals, slapping his photos—bald, beefy-faced and smiling faintly—on "Wanted" fliers posted online. The Russian would be an ideal ...

Cyber threats expanding, new US intelligence assessment says

February 26, 2015

(AP)—The U.S. has elevated its appraisal of the cyber threat from Russia, the U.S. intelligence chief said Thursday, as he delivered the annual assessment by intelligence agencies of the top dangers facing the country.

Avian malaria also affects wild birds in Austria

February 10, 2015

Avian malaria is not uncommon in Central Europe, as many endemic wild birds are infected with species of Plasmodium, which cause avian malaria. In most cases these blood parasites, transmitted by mosquitoes, do not produce ...

Recommended for you

Detecting HIV diagnostic antibodies with DNA nanomachines

October 7, 2015

New research may revolutionize the slow, cumbersome and expensive process of detecting the antibodies that can help with the diagnosis of infectious and auto-immune diseases such as rheumatoid arthritis and HIV. An international ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.