Guarding the Henhouse

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By contrast, the 2004 outbreak--also a low-pathogenic strain of H7N2, which struck on the Delmarva Peninsula--was discovered right away, and both the states and the industry jumped into gear, euthanizing flocks, setting up quarantines and compensating farmers for their downed birds. "You had guys from Mountaire Farms and Perdue Farms working side by side," says Chisholm. "That's unusual because this is a competitive business." The quick response limited damage to just three farms.

Of course, before you can contain a sick farm, you have to know where it is. That's where the latest in geolocating devices comes in. Poultry veterinarians have been mapping U.S. commercial farms with handheld GPS tools (similar to the electronic navigational readers many people have in their cars) and entering the locations into large computerized databases for use in an emergency. They have even used the popular free software program Google Earth to fine-tune the positions of some chicken houses. That way, if the industry's testing program ever turns up evidence of H5N1 infection, officials will know exactly which flocks to sacrifice and where to draw the quarantine lines.

Vaccinating against avian flu could potentially avoid those problems since inoculated chickens don't get sick in the first place. But while some European farmers have begun doing just that, the idea seems impractical in the U.S. "If you have to put down a flock, you lose maybe 50,000 birds," notes Lobb. "That is much easier than trying to vaccinate 10 billion birds, which is about what we will produce this year."

Another way to protect flocks is to block the virus from ever alighting here. Whether that can be done depends on how the pathogen arrives. Everybody's favorite suspects these days seem to be migrating birds. If you check a map of migration flyways, it's pretty easy to trace a potential route for an infected bird from Europe to Canada and then on down through the U.S. But would that really happen?

"Even though the big flyway maps look like they overlap, the birds themselves don't," says Dr. William Karesh, director of the field veterinary program of the Wildlife Conservation Society. Gene studies of avian-flu strains from the past 30 years seem to confirm that, with no evident commingling among the viruses. "The birds of the New World and the birds of the Old World don't share their viruses," Karesh says. "That doesn't mean it's impossible. That would be irresponsible. But it doesn't happen normally."

In any event, most commercial chicken houses (where the birds spend their entire lives indoors) have no contact with migratory birds. Even free-range chickens are generally not clucking all over hither and yon and so can easily be brought indoors if need be. That still leaves the exotic-pet market (legal and illegal) and the illegal importation of poultry products. Connecticut recently confiscated a load of imported chicken feed labeled JELLYFISH.

Whatever measures the government imposes, commercial poultry farmers are about as prepared as they can be. "You can't stop bringing feed to the farm," says Doug Green, 53, who has four chicken houses in Princess Ann, Md. "You can't stop bringing fuel. There's a certain amount of interaction that has to go on." Controlling that amount is where the difference between sick flocks and healthy ones will lie