NEW YORK December 4, 2006 Scientists at the Consortium for Conservation Medicine (CCM), the Royal Society for the Protection of Birds, and the Smithsonian Institution's National Zoo report that H5N1 avian influenza is most likely to be introduced to countries in the Western Hemisphere through infected poultry trade.

Following the initial outbreaks of H5N1 avian influenza in Hong Kong, scientists and government officials worldwide have debated exactly how the virus was being spread and what could be done to stop it.

Dr. Marm Kilpatrick, senior research scientist with the Consortium for Conservation Medicine, led the team in their efforts to predict the most likely method of introduction to the U.S. Dr. Kilpatrick and colleagues predict that bird flu will most likely be introduced to countries in the Western Hemisphere through infected poultry trade rather than from migrating birds from eastern Siberia, as previously thought. The subsequent movement of infected migrating birds from countries south of the U.S. would be a likely pathway for H5N1 avian influenza to reach the USA.

The research will be published online in the Proceedings of the National Academy of Sciences in December.

Avian influenza has reached more than 50 countries, and millions of chickens have been either infected and/or culled to prevent the spread of the virus to other poultry farms. Estimated financial losses are in the tens of billions of dollars from its spread. In addition, 258 people have been infected and 153 human deaths have occurred, with most cases in Vietnam, Indonesia, Thailand, and China.

This new research set out to identify the pathways for individual H5N1 introductions as the virus spread through Asia, Europe and Africa. The predictive modeling approach used by the researchers offers substantial promise for understanding past introductions, the pathway for new introductions, and ways to prevent future spread of the deadly virus.