Bird flu panic.

The state of the universe.
May 8 2006 1:39 PM

The Mutant Chickens Are Coming!

The silliness of bird flu panic.

Joely Richardson, Justina Machado, and Stacy Keach.  Click image to expand.
Joely Richardson, Justina Machado, and Stacy Keach 

Millions die, heaps of bodies are set alight on mass pyres, and government officials wearing moonsuits mumble bad dialogue in Fatal Contact: Bird Flu in America, a made-for-TV disaster movie airing on ABC Tuesday night. The premise is that avian influenza is about to mutate and become unstoppable, reducing much of the United States to ruins. ABC says the movie has been vetted by specialists and "meticulously researched"—the idea of researching something that has not happened being the latest frontier in "truthiness." Airing during May sweeps, Fatal Contact is supposed to represent an awful vision of a future that actually might come to pass.

OK, it's a disaster movie, so of course it's over the top. But television programmers are hardly the only ones over the top on bird flu. David Nabbaro, a World Health Organization official, has said a bird flu pandemic might kill 150 million people; the WHO formally warns of up to 7.4 million global deaths. The White House's avian flu response plan, announced last week, projects that as many as 2 million Americans might die. The president should be prepared to send the Army into cities to put down bird flu riots, the plan asserts. Robert Webster, a prominent influenza researcher, told ABC's World News Tonight that a pandemic might kill half of the human population. Webster says he is keeping a three-month supply of food and water at his home, apparently in case the American economy collapses during a bird flu outbreak. Paranoid? Michael Leavitt, secretary of the Department of Health and Human Services, recently advised Americans to stockpile six weeks' worth of food, water, and medicine in their homes. Specifically, Leavitt recommends storing powdered milk and tuna fish under the bed. Last week, a report by the consulting firm Booz Allen Hamilton even speculated that "the Internet could shut down within two to four days" of a bird flu outbreak.

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All this for a disease that since 2003 has killed 113 people worldwide. During the same span, about 4 million have died worldwide in traffic accidents. The number of these deaths is rising steadily in most nations, with road fatalities on track to become the world's third-leading cause of death—that is, traffic accidents look exactly like a pandemic. Also since 2003, at least 6 million people worldwide have died of diarrheal diseases, with about 1.5 million of those deaths attributed to rotavirus, which has spread in pandemic fashion. Yet the panic button has been pushed only for bird flu. Why?

There is one justifiable reason and lots of bad ones. The justifiable reason is that recent experience shows pushing the panic button is an effective way to prevent a disease from taking hold. In the last two decades Ebola, SARS, and West Nile virus have all been the subjects of doomsday prophecies followed by panicky government response, and all have been contained with little general harm, except in a few parts of Africa. Overreaction by the WHO, Western donor governments and, especially, Asian governments is far preferable to inaction.

At the same time, a bird flu pandemic appears extraordinarily unlikely. First, a pandemic would require the worrisome H5N1 strain to mutate significantly. Currently H5N1 is not transmissible from person to person. A bird can transmit the disease to another bird, and a person who is in close contact with an infected bird can catch it from the bird, but an infected person cannot transmit the disease to another person. Since the overwhelming majority of the global population never comes into close physical contact with birds, the existing H5N1 strain poses almost no threat—as evidenced by the low fatality numbers thus far. If bird flu mutated in a way that allowed person-to-person transmission, this would be very dangerous. But the odds of such a mutation appear low, as explained in depth here.

Animal influenzas have become person-to-person transmissible in the past. Many commentators who have looked at the flu pandemic of 1918-19, which the WHO says killed 20 million to 40 million people, projected the same death rate onto today's far larger global population, and gasped. But there were three flu pandemics during the 20th century, and each was lessvirulent than the last. The 1957 pandemic, caused by the H2N2 virus, killed 1 million to 4 million worldwide, though the global population was significantly higher in 1957 than in 1918-19. The 1968 Hong Kong flu, caused by the H3N2 strain, also killed 1 million to 4 million, but again the global population had increased. (Go here and click "influenza pandemics of the last century.") In other words, the death ratio of flu pandemic declined throughout the century—fewer killed compared to larger numbers of people alive.

Contemporary bird flu panic is most mistaken in overlooking the improvements in global public health made since the pandemics of the past. The 1918-19 pandemic came before antibiotics and sulfa drugs and occurred at a time when public health was poor in many nations owing to five years of brutal war. Post-antibiotics and with most of the world at peace, the 1957 and 1968 pandemics were much less destructive. Today, a person-to-person H5N1 strain would be loosed on a globe where public health has made further gains and which is mostly at peace.

The point isn't that antibiotics could be used against the flu, which is unaffected by the chemical descendants of penicillin. It's that antibiotics, vaccines, and many other public health improvements make today's global population more resistant to all diseases than populations of the past. Whether a person exposed to a pathogen contracts the disease is tremendously influenced by the state of the person's health. The body of a person in good basic health—that is, not already sickened by something else—will fight off most pathogens. This is why hospital patients often contract pneumonia, strep, and staph while doctors and nurses do not contract these diseases. Today the majority of the citizens of the world are in good basic health. If a transmissible H5N1 mutation happens, it likely won't jump wildly from person to person, leaving piles of the dead to be placed upon pyres, because most people's bodies will defeat the pathogen.

The global decline in malnutrition will also help us. A malnourished person is far more susceptible to disease than a well-nourished person. "Chronic hunger is on the decline," the latest report from the United Nations' Food and Agriculture Organization states. (Go here and click "United Nations 2005 hunger report.") Today an estimated 17 percent of citizens of developing nations are malnourished. That figure is an outrage. But it is also believed to be the lowest such figure in human history. About a third of the developing world was malnourished when the 1968 pandemic occurred. And perhaps as much as half the developing world was malnourished in 1918-19.

The lack of mention of improved global public health in discussion of bird flu hazards is telling. One reason for it is that the media and politicians often seem uninformed about public health trends. (Quickly, are cancer rates rising or declining? OK, I gave it away.) Another reason is a lack of basic understanding of evolutionary biology; runaway genetic effects are not observed in nature because natural selection has spent eons conditioning living things to resist runaway genetic effects. Then there is science fiction, from Kurt Vonnegut's "ice nine" to Michael Crichton's Andromeda Strain, which has created the illusion that very tiny amounts of something can instantly cause global catastrophe. (In Fatal Contact, one single exposed person rapidly infects much of the population of United States.) Finally, preposterous movies such as Outbreak and best sellers such as The Cobra Event, which depicted an unstoppable super-ultra-plague and which Bill Clinton read while at the White House, have left our collective heads spinning. Right now the ultimate book proposal might be for a plagiarized "memoir" full of invented scenes about someone who contracts bird flu while finding suppressed documents about Jesus. Hmm—excuse me, I gotta call my agent!