While the pure panic over a global avian flu pandemic seems to have died down, the virus continues to spread. To date, H5N1 has showed up in 55 countries, but has not yet touched the Western Hemisphere. Also to date, the U.S. government has assumed that the most likely route for bird flu’s arrival into the lower 48 would be through wild birds; accordingly, they’ve put some $29 million into surveilling wild birds migrating from Asia to Alaska and down.

However, a study published yesterday in the Proceedings of the National Academy of Sciences by a few groups with looong names (deep breath: the Consortium for Conservation Medicine, Royal Society for Protection of Birds, and Smithsonian Institution’s National Zoo) suggests that the poultry trade is likely to be the biggest culprit if bird flu spreads to the Western Hemisphere. Indeed, instead of being infected by birds that wander through from eastern Siberia, the U.S. is more likely to be infected by birds traveling from our neighbors Canada and Mexico, or from Brazil. Mexico and Brazil have no testing or quarantine system for the hundreds of thousands of chickens imported each year; in its wisdom, the U.S. Department of Agriculture currently waives the normal 30-day quarantine on poultry imported from the Great White North. Brazil, Canada, and Mexico all trade poultry with other nations where birds have been infected by the avian flu virus.

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“There is overwhelming evidence that wild birds and poultry are both involved, and that the two synergistically enable a very rapid spread of the virus,” says disease ecologist Marm Kilpatrick. As to American readiness, the study concludes, “current American surveillance plans that focus primarily on the Alaskan migratory bird pathway may fail to detect the introduction of H5N1 into the United States in time to prevent its spread into domestic poultry.”

I hope we can pullet out.

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