Spreading Its Wings
It's only a matter of time before Bird flu reaches the United States. Can we stop the killer virus?
"The poultry industry in the United States is well prepared to detect and manage an outbreak," says Nina Marano, associate director for veterinary public health for the Centers for Disease Control and Prevention, who specializes in zoonoses, or diseases like H5N1 and West Nile virus that pass from animals to humans. She frets more about protecting the country's approximately 50,000 hobby flocks, as well as exhibition birds and live poultry markets.
The country's major zoos, which are shelters of last resort for endangered species, and also commonly host chickens, wild ducks, and geese, are buttoning up plans to deal with H5N1. Those range from shutting down walk-through aviaries to quizzing visitors on their recent travels. "You can't eliminate wild birds," says Robyn Barbiers, a veterinarian at Chicago's Lincoln Park Zoo who chairs the American Zoo and Aquarium Association's animal health committee. When West Nile virus arrived in the United States in 1999 and started killing wild birds, everyone was nervous, she says. "We dealt with it," says Barbiers. "I don't think avian influenza is going to be as disastrous as people envision."
But H5N1 could prove disastrous in countries like Nigeria, where the virus has been detected on more than 130 poultry farms in the past month. Webster says when he lies awake worrying, it's about places like Africa where lab capacity, cash, and expertise are all scarce. "I worry that the virus will end up in humans and not necessarily be detected," he says. It would take just one sick person on an overseas flight to ignite a pandemic.
Last week, health officials from around the world met in Geneva to talk about how to stop a pandemic--something that has never been attempted, let alone realized. Intensive surveillance of animal and human flu cases would be essential to containment, providing enough time to vaccinate people and treat them with antivirals before the disease could spread.
Until H5N1, notes Webster, the world wasn't interested in bird flu. "Who gives a damn about a virus that's out there in wild birds and doesn't do anything? Now we know," he says, "that we do have to understand the natural history of these things, because they do have consequences."
Since 2003, the deadly H5N1 strain of avian influenza has spread from its origins in Asia into Europe and Africa, infecting millions of birds. At least 96 people have died.
First confirmed cases of H5N1 flu in birds
Sources: World Organization for Animal Health; World Health Organization