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Avian Flu: What You Need to Know
Maybe it's winging its way here; maybe it isn't. Maybe it'll start jumping from human to human; maybe it won't. Here are the best-case, the worst-case, and the just-in-case scenarios.
By Barry Yeoman
Originally published in O, The Oprah Magazine, June 2006
THE DAILY NEWS IS SO FULL OF GRIM REPORTS about avian flu, it's hard not to be in a constant state of alarm. Once confined to Southeast Asia, the infamous H5N1 influenza strain has now spread to countries as far-flung as France, Iraq, Nigeria, Russia, and Turkey, causing as many as 200 million birds to be wiped out. More than 100 people have died from the disease, leading scientists to warn of a disaster comparable to the 1918 Spanish flu pandemic that left up to 50 million people dead worldwide. Marketers are starting to cash in on our fears: One of the first Web sites to pop up from a "bird flu" Google search predicts "long 'bread lines' of infected people" and "roving gangs wanting to steal your food," then advertises emergency equipment that many experts consider unnecessary.
In reality, how this flu will affect us is unclear. Yes, there is a distinct possibility that the virus will come to the United States. If infected waterfowl migrate to Alaska during the summer, for example, and mingle with other birds that travel throughout the lower 48 states, "we could see it as soon as this fall," says Richard Fulton, PhD, an associate professor of avian diseases at Michigan State University. But that wouldn't necessarily lead to a pandemic: In its current form, avian flu is quite difficult for people to catch. Most of the diagnosed cases have been caused by touching infected birds or surfaces contaminated with their droppings.
The real danger would come from a genetic mishap, an evolutionary hiccup that allows for easy human-to-human transmission. There are a couple of ways this could happen, but the most probable is called reassortment: If a person (or another animal, like a pig) contracted both human and bird flu simultaneously, the two strains could trade genetic information and produce a fast-spreading hybrid. This is easy for flu viruses to do, because they're composed of eight relatively interchangeable gene segments. Scientists believe it was reassortment that launched the last two pandemics—the 1957 Asian flu and 1968 Hong Kong flu.
The result of reassortment with H5N1 could be a new virus for which "there's no immunity in humans," says Jeremias L. Murillo, MD, an epidemiologist at Newark Beth Israel Medical Center. "So there would be virtually no protection." (The death rate for people infected with the current H5N1 strain has surpassed 50 percent because of that lack of immunity.) Reassortment is not inevitable, but an article in the journal Science predicted a 50-50 chance if more than 600 people worldwide get sick. As of late March, there were 186 confirmed cases.
Alternatively, H5N1 could gradually evolve into a more treacherous bug. Scientists note that it has already undergone some ominous changes, becoming increasingly lethal in wild birds and also infecting cats. "There's something a little sinister about it," says C.J. Peters, MD, a professor of pathology, microbiology, and immunology at the University of Texas Medical Branch in Galveston. "I'm not saying it's the virus that ate Manhattan. But if we end up with a highly virulent, highly transmissible strain, it would be the biggest health disaster we've ever seen in this country."
Scientists tracking the flu's mutations forecast different outcomes. "But most think that within a few years, it will be able to jump from person to person," says S. Ward Casscells, MD, vice president for biotechnology at the University of Texas Health Science Center at Houston. If that happens, proliferation would likely move from duck speed to jet speed overnight as infected citizens—not yet showing symptoms—continued to travel, lugging the virus with them. Trying to figure out just how rapidly the disease might spread, researchers at Johns Hopkins University used airline data to show that had the 1968 Hong Kong flu surfaced in 2000, it would have circled the globe within six months, almost twice as fast as it actually did.
That could wreak havoc in the United States. Human flu kills about 36,000 Americans each year, and avian flu would almost certainly take a higher toll. According to the U.S. Department of Health and Human Services, by the time a moderate pandemic runs its course, it could produce 209,000 fatalities in this country, while a severe one could raise the death toll to 1.9 million—not just children and the elderly but also young, previously healthy adults. Those who acquired the illness would likely suffer teeth-chattering chills, high fevers, muscle aches, and nausea, and if they survived, protracted convalescences. Unchecked, any flu can also cause delirium and pneumonia, though the avian version would be more likely to do so because of the lack of human immunity.
ACCORDING TO PLANNING DOCUMENTS from the U.S. Department of Health and Human Services and two regional health departments—New York State and Seattle—a serious bird flu pandemic could force schools and businesses to close. At its peak, it could drive up job absenteeism to 40 percent. Overrun hospitals would press medical students into service; a shortage of doctors and nurses might "also necessitate utilizing ill healthcare workers who are well enough to administer patient care," notes New York's pandemic-flu plan. Moreover, items like food and batteries could become scarce as factories lose workers and truckers refuse to enter affected areas.
Scientists are racing to avert such scenarios. The U.S. government is working on several bird flu vaccines in the hope that one of them will be effective. But a specific flu shot can't be developed until the exact strain in circulation is identified. It would then take about six months before the vaccine could become available—and by that time the avian virus would have already spread around the world, according to the Johns Hopkins model. Adequate supply is also an issue. The United States currently produces only enough vaccine to protect 50 million people a year, according to Robert Belshe, MD, director of the Center for Vaccine Development at Saint Louis University School of Medicine. "That wouldn't be nearly enough for a pandemic." What hampers production is that flu shots are made with an antiquated technology, calling for millions of fertilized chicken eggs to serve as hosts for the virus. In the case of bird flu, it's possible that chickens would be harder to come by.
At the same time, there could be a shortage of Tamiflu, the medication that offers the most promise against avian flu by stopping the virus's spread once someone is infected. That doesn't mean individuals should hoard Tamiflu, which is made by Roche Laboratories and already in short supply. "If people stockpile it, we won't have the drug available where we need it," says Neil Fishman, MD, director of healthcare epidemiology and infection control for the Hospital of the University of Pennsylvania. Besides, we don't even know if Tamiflu will prove effective against pandemic H5N1. "Unfortunately, there have been documented cases of avian flu resistance to Tamiflu," says Bruce Hirsch, MD, an infectious disease specialist at North Shore University Hospital in Manhasset, New York. "This medication that has been touted as the main weapon in our arsenal already has holes in it."
As fears about vaccine and drug shortages take hold, a whole underground disaster industry is gathering force. The Internet is overrun with marketers of products like equipment to produce colloidal silver, which one firm claims is a bird flu remedy (the U.S. Food and Drug Administration considers the substance medically risky). Self-styled Internet pharmacies, many of them over seas, illegally offer Tamiflu without a prescription. Experts urge consumers to turn to reputable information sources in stead. The federal government runs a comprehensive Web site at pandemicflu.gov, and the Centers for Disease Control and Prevention continuously updates information at www.cdc.gov/flu/avian. The University of Illinois offers information that you can download onto your cell phone: Go to publichealthgames.com.
Ultimately, despite all the dire predictions, we're much better off than in the past. The 1918 flu pandemic decimated a generation. The next one doesn't have to. "We have so many advantages," says Hirsch. "We have communications. We have technology. We have medications that show promise. But we need common sense." Americans must make sure everyone in the community gets the avian flu vaccine once it's out. Also, employees and students must be encouraged to take sick leave when necessary. "The bias we have against absenteeism in our bottom-line-oriented society will be seriously misplaced when we run up against a flu pandemic," Hirsch says. "A person who is sick and stays at home is a hero."
Most important is not to panic, says Felissa Lashley, PhD, interim director of the Nursing Center for Bioterrorism and Emerging Infectious Diseases Preparedness at Rutgers University. "We don't have avian flu here now," she says, and obsessing over what may or may not hap pen is a waste of energy. "People should continue to do the things they'd do anyway for good health: Eat right, wash your hands, don't cough and sneeze in people's faces. And I certainly wouldn't want to be mud-wrestling with a chicken."
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