Of birds and men
A deadly virus is brewing in Asia. Could this be the next killer pandemic?
Jean Taylor is trying to figure out how to live with a killer, one that could wipe out tens of thousands of people in the state of Maryland in just a few weeks. The epidemiologist is asking where sick people will be taken if the hospitals are overwhelmed; when schools and businesses should be ordered closed to reduce the spread of infection; and who will still be standing to deliver food to supermarkets, to pump gas, to bury the dead.
Across the country, federal, state, and local officials like Taylor are trying to figure out how the United States would cope with a killer flu, one that would be very different from the usual influenza that strikes each winter. A global epidemic, or pandemic, would be caused by a new, lethal flu virus, one to which people would have no immunity. The new flu would spread around the world within weeks and could infect one third of all people, killing 1 to 5 percent of them. That's what happened in 1918, when the Spanish flu killed 25 million in six months; some historians place the total killed at 100 million. Since then, two other far less lethal flu pandemics, in 1957 and 1968, have swept the globe. "Nature is the worst terrorist you can imagine," says Harvey Fineberg, president of the Institute of Medicine and former dean of the Harvard School of Public Health.
Flu viruses are notoriously good at mutating into new strains, and sooner or later one will morph into a mass killer. No one can say when that will happen; scientists say it could be this year, or 20 years from now. But in recent months normally sanguine health officials have been making increasingly dire predictions of a nightmarish 1918-style assault, one that could kill up to 2.2 million people in the United States. "We at WHO believe that the world is now in the gravest possible danger of a pandemic," says Shigeru Omi, Western Pacific regional leader for the World Health Organization. Those words echo Julie Gerberding, director of the federal Centers for Disease Control and
Prevention, who called the current situation "a very high threat."
The doctors are spooked by the continuing outbreaks of a new strain of avian influenza that has sickened at least 69 people and killed 46 in Vietnam, Thailand, and Cambodia in the past 16 months. One more death, of a 26-year-old man in Cambodia, was reported last week, and Vietnamese authorities are investigating a village where a 5-year-old fell ill with the disease in mid-March, shortly after his 13-year-old sister died. This new virus, called H5N1, is from the same family as the killer 1918 strain. Flu typically kills the old and weak, but with the new flu, most of the victims have been healthy young people. The 1918 flu killed the young and healthy, too.
The doctors are alarmed not because of the number of people that "bird flu" has killed but because the H5N1 virus displays an ominous adaptability and persistence. About 70 percent of those infected so far have died. Since 1997, when the new virus first showed up in chickens and killed six people in Hong Kong, it has spread to birds in eight countries in the region despite repeated efforts to halt it by slaughtering millions of chickens. "The virus has gotten even more widespread," says Klaus Stohr, head of influenza for WHO.