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It would be easy to dismiss bird-flu scaremongering were it not for history: In March 1918, a particularly virulent strain of flu broke out at a military base in Kansas and then stowed away to Europe inside American soldiers, who ferried it back to the States the same fall. Its spread, and the secondary pneumonia infections that often resulted, were devastating. As many as one-quarter of US citizens became infected, and by the time the "Spanish flu" pandemic flamed out, more than 600,000 Americans had died -- almost 200,000 succumbed in October 1918 alone. The virus culled not only the old and infirm but healthy young adults as well. As the 1999 PBS documentary Influenza 1918 showed, the scenes that ensued were worthy of Stephen King novels. Men walking down the street crumpled over and died. Death carts roamed Philadelphia. Undertakers had to hire guards to scare off coffin thieves. Some cities forbade public assembly, and thousands of schools closed down.
The United States had it easy: Estimates of the worldwide death toll range from 30 million to 50 million. And when scientists recently reconstructed the original, most virulent form of the virus from long-stored samples of victims' lung tissue, they confirmed that it was an avian flu.
If a pandemic of similar scale were to break out these days, the federal government estimates the US death toll could reach 1.9 million, more than double the number of Americans killed in all of our wars combined. Hospitals and morgues would be outmatched. Public panic is likely. And with people unable to work and conduct everyday commerce, the economy would almost certainly spiral into severe recession.
There are many forms of avian influenza, but the virulent H5N1 strain we're hearing so much about is particularly worrisome to public health officials because it is capable of jumping from birds into people. The first human case was reported in Hong Kong in 1997, and soon H5N1 began appearing all over Southeast Asia. Now the CDC considers it endemic to that region. Most of the poultry raised in countries such as Vietnam and Cambodia ranges freely outdoors, interacting with wild birds that have picked up the bug and flown it as far west as Romania, Turkey, and Croatia.
Based on available numbers, H5N1 is highly lethal: Of the 88 human cases reported to the World Health Organization since last December, 36 have proved fatal -- a 41 percent death rate -- and these are just the lab-confirmed cases.
The world now stands at stage three on the World Health Organization's six-step scale of pandemic risk, firmly in the yellow zone. The real nightmare scenario is that the bird flu will mutate, making it transmissible person to person and sparking a worldwide pandemic.
Even if that never occurs, H5N1 is likely to keep dogging the $23 billion US poultry industry. "This virus is a very serious virus, the likes of which we've never seen," says Carol Cardona, poultry health and food safety specialist with UC Davis Veterinary Extension.
Cardona studies avian influenza, and H5N1 concerns her for many reasons. "In the past, we have not seen a bird virus move between wild and domestic birds so easily," she says. "Most viruses are more species-specific, and don't cause more than a cold. That's something you can live with. This virus, however, appears to move in wild birds and then get into domestic poultry, and kills 100 percent of chickens. And that's not something that anyone can live with. Plus, the human transmissible potential is very frightening."
International agricultural agencies are desperately trying to get small farmers across Asia to fence in their poultry instead of letting them forage freely. At the first sign of H5N1's arrival on the continent, Europe, which seemed so far ahead of the States on the animal-welfare front, began to panic over free-range chicken and eggs. Authorities there have banned imports of live birds and forced cancellation of bird shows, while France, England, and the Netherlands have all asked free-range poultry farmers to bring their flocks indoors. Israel's Agriculture Ministry announced on November 1 that it was banning free-range poultry. Sales of free-range meat and eggs have dropped in Britain, despite assurances from health agencies that properly cooked meat and eggs pose no health risk.
Cardona believes the threat of H5N1 making it to the United States -- through wild birds migrating to Alaska over the Pacific Flyway, or infected birds shipped from Asia -- is relatively low. "But the stakes are too high to take any risks at all," she cautions. As the federal government girds for a possible epidemic, it is taking poultry into account. As part of President Bush's proposed $7.1 billion avian-flu response, the USDA has asked for $73 million to build the nation's animal-vaccine stockpile, monitor wild birds and bird smugglers, and conduct preparedness training.
Although most Californians have never heard of it, another virulent bird virus has left California's agricultural industry better prepared to deal with avian flu than our human public health system is. An outbreak of the exotic Newcastle virus among Southern California flocks in 2002 and 2003 led to the state's worst poultry crisis in more than three decades, and resulted in the slaughter of 3.1 million birds statewide. The USDA put the cost to federal and state agencies at $180 million. And when the USDA's Animal and Plant Health Inspection Service and the California Department of Food and Agriculture moved to control the outbreak, the two agencies were surprised to discover just how many people were raising poultry in their backyards. Those backyard chickens, Cardona adds, were the first flocks in which the virus took hold.
Even in the wake of exotic Newcastle, there are no national, California, or local biosecurity mandates for poultry, whether the birds are raised in massive barns or on someone's lawn. But during the 2002 outbreak USDA inspectors, state officials, and UC Davis all developed recommendations to help safeguard poultry flocks. Since then, the USDA has advertised its nationwide "Biosecurity for the Birds" campaign through such venues as feed stores and ethnic-community newspapers -- even printing messages on sacks of grain -- to get small-time growers to better protect their birds and report any signs of disease.
Some of the people raising poultry in our midst have heard of these precautions. The majority have not.