The View from Sapsucker Woods

A Louisiana physician uttered a telling comment several years ago during the height of the West Nile virus media scare. Interviewed because the virus had spread west to the Mississippi River, he remarked, "I am fed up with seeing overweight patients who smoke heavily, drink too much, and never exercise, who tell me they are deathly afraid to go outdoors for fear of catching West Nile virus!" He spoke the plain truth about our need as a society for Risk Assessment 101.

According to the Centers for Disease Control (CDC), West Nile virus has killed a total of 782 humans in the United States since 1999, an average of about 111 deaths per year. This number is only marginally higher than the annual death rate from lightning strikes, which averages about 82 per year, according to the U.S. National Weather Service. In contrast, heart disease kills more than 927,000 Americans annually--about one death every 34 seconds, according to the CDC.

Our weakness at assessing risk and behaving accordingly reflects progressive dulling of our once-superb animal instincts. Most advances in human society, after all, represent progressive elimination of risk from our daily lives. Domesticating plants reduced our risk of starvation. The discovery of antibiotics dramatically reduced our risk of dying from infection. Anesthesia reduced our risk of debilitating pain and shock, thereby facilitating modern surgery. Gasoline, jet engines, and airbags reduced the unpredictability and hazards of travel. It is no wonder that by now few of us know how to gauge how much risk is really involved when we hear about a new disease potentially on the horizon. We should face this failure in ourselves, and consciously work to correct it, for the costs of needless fear can be staggering.

Bird flu, or avian influenza, is the disease du jour. Based on recent media coverage and public concern, one might never guess that in all of North America there have been no infections, let alone deaths, from the highly pathogenic H5N1 virus. This strain has caused 109 deaths in other countries, mostly Asia, since 2003, but even if it does make its way here there is no cause for panic. The disease is extremely difficult to contract, is not easily transmitted from birds to humans, and is even harder to move from human to human. In all well-documented cases, the disease is believed to have spread to humans through physical handling of infected poultry or poultry products.

There are no known cases of wild birds transmitting highly pathogenic H5N1 to humans, and the evidence is meager that any wild birds are moving it around the world. Yet we have begun hearing calls for culling wild birds and draining wetlands near human settlements, and we?ve even heard about people who are afraid to allow children to play outdoors. Such overreactions are unfounded, given all that is known about the disease. Monitoring the incidence of this disease in wild birds is warranted at this time, but discussions about wild bird control will never be. Detailed study of the ecology of high-path H5N1 is warranted. Fear is not.

If you are genuinely worried about avian flu, then here is what you should do: (1) cancel any upcoming tours you have booked to visit poultry farms in the Old World; (2) if you insist on visiting the poultry farms, don?t sleep with the chickens; (3) do not purchase wild birds that were illegally smuggled from foreign countries; (4) if you?re still worried, see page 16 for the tips we?re recommending about keeping your hands and bird feeders clean; (5) keep checking the Cornell Lab of Ornithology?s web site on avian influenza at www.birds.cornell.edu/birdflu to stay abreast of the latest information summarized from the international scientific community.

The best way to reduce risk is to be armed with facts and probabilities about what could go wrong, and then act logically with those facts as a guide. The best way to reduce hysteria is exactly the same.

--John W. Fitzpatrick, Louis Agassiz Fuertes Director

For permission to reprint all or part of this article, please contact Laura Erickson, editor, Cornell Lab of Ornithology, 159 Sapsucker Woods Rd., Ithaca, NY, 14850. Phone: (607) 254-1114. email: lle24@cornell.edu