The Revenge Of the Birds

By Anthony Spaeth/Hong Kong

The white coffin of Kaptan Boonmanuj, 6, is installed in the front room of his family's farmhouse in western Thailand. A framed photo shows Kaptan in his school uniform; nearby, someone has parked his little bicycle. Kaptan fell ill a few days after the New Year with a mysterious fever that developed into lung complications. "Mum," he told his mother, "my chest feels like it is going to explode." When he died last week, Kaptan became Thailand's first confirmed victim of avian influenza, the latest scourge to emerge from Asia. Inside the Boonmanuj household, relatives burn incense and quietly weep. Outside, chickens scratch around the yard freely--birds not so different from the ones that made Kaptan sick.

The bird flu that is spreading with alarming speed through Asia's poultry farms--killing thousands of chickens in 10 countries and forcing the slaughter of millions more--has so far infected a relatively small number of humans. Fewer than a dozen people in Vietnam and Thailand have caught the flu, all by direct exposure to infected chickens, and there is no evidence yet of the disease spreading from one person to another. But when humans do catch it, it is extremely deadly; at least eight people have already died, most of them children like Kaptan. And the great fear of health officials around the world is that the virus could, like SARS, jump the species barrier, mutate into a deadly and highly contagious form and set off a worldwide pandemic.

The odds of that happening are still small, and the risk to Westerners who do not come into direct contact with Asian birds is infinitesimal, according to the U.S. Centers for Disease Control. But the farther the virus spreads, and the more people who become infected with it, the greater the risk.

Health officials have long been worried that the next deadly global epidemic--a slate wiper, as epidemiologists call it--would be a new kind of deadly flu to which humans have no resistance. And since the 1960s, their fears have been focused on the H5N1 virus, a bird pathogen that is generally harmless in its host species (ducks and other wildfowl) but extremely deadly when contracted by chickens. It was H5N1 that struck Hong Kong in 1997, where it went straight from chickens to humans. Authorities quickly killed 1.4 million birds, and although six people died, the disease never managed to mutate into a highly contagious form.

What scares scientists most about H5N1 is that someone eventually will be stricken by the bird flu and a human flu at the same time, allowing the viruses to swap genetic material. The resulting hybrid could be both deadly and virulent. Even if it weren't immediately contagious, it could quickly evolve. A study published last week in the journal Science reported that the SARS virus mutated in a matter of months from a form that could infect only 3% of people who came in contact with it to one that infected 70%. Once it mutated, SARS quickly spread around the world, infecting thousands and killing more than 900. A hybrid H5N1 could be far deadlier.

Hong Kong's 1997 experience alerted the world to the dangers of bird flu and offered a lesson on how to control it: kill sick chickens, and do it as fast as possible. That lesson obviously didn't sink in. Vietnam, the third country to acknowledge the presence of bird flu (after South Korea and Japan) in December, had outbreaks as far back as July. Birds started dropping dead in Thailand in early November, but the government insisted until last week that the chickens merely had a bacterial ailment. Heavily populated Indonesia has been hard hit but refused to cull any of its flocks until last week.

The virus probably originates in southern China, but no one knows how it has spread so widely. Transport of infected birds to chicken farms is one theory, but it's also possible that migratory birds such as ducks and geese are spreading it through their droppings. "Did birds in Hong Kong, which nest in Siberia and North Korea, somehow spread the virus elsewhere?" asks Robert Webster, an expert in animal influenzas at St. Jude Children's Research Hospital in Memphis, Tenn. "That's a frightening possibility." If H5N1 does evolve into a flu that humans can spread, a vaccine could be developed but would take months. "Once you know this virus can spread from human to human, region to region," says Dr. Yi Guan, a SARS and avian-flu expert at the University of Hong Kong, "it's already too late."

Dissembling and stalling by local governments have already allowed the pathogen to spread in Asia--not only in birds but also among the men and women who raise them for a living and the kids who gather eggs or simply kick up infected dust in their villages. "If I had known about the bird flu," says Roongroj Boontang, the uncle who allowed Kaptan Boonmanuj to play with his fighting roosters, "my nephew would still be alive." --Reported by Andrew Perrin/Ben Ya Pad, Karl Taro Greenfeld and Bryan Walsh/Hong Kong and David Bjerklie/New York

With reporting by Andrew Perrin/Ben Ya Pad, Karl Taro Greenfeld and Bryan Walsh/Hong Kong and David Bjerklie/New York