Safe Food_ Bacteria, Biotechnology, and Bioterrorism - Marion Nestle [154]
Anthrax is normally a veterinary problem. Infected animals are so visibly sick that farmers cull them before they get into the meat supply. Infected cows are too sick to produce milk, or they produce milk of unusable quality, which is why milk and cheese are not known sources of anthrax. Digestive acids and enzymes—and cooking—ordinarily kill the bacteria, and people seem to have some natural immunity. Because heavy bacterial infestations overcome these defenses and spores resist them, people occasionally acquire anthrax from eating undercooked meat from sick or downer water buffalo, goats, sheep, and cattle. Even so, food-borne anthrax is so rare that medical journals like to report the occasional cases. In August 2000, for example, Minnesota health officials described an outbreak of anthrax in a farm family whose members ate meat from a downer steer. When family members became ill, investigators discovered that the carcass was heavily infested with anthrax bacteria.25
Anthrax would be almost nonexistent in people if eating it were the only route of infection, but it also causes disease through the skin and lungs. The skin disease comes from handling infected carcasses. The lung disease comes from breathing in spores from infected animal skins or soil. These forms also are relatively rare. In the United States, health officials reported about 225 cases of the skin disease over the 50-year period from 1944 to 1994. In 2001, they added to this total a man in North Dakota who had disposed of five cows dead of anthrax. Officials logged only 18 cases of inhalation anthrax from 1900 to 1978, and just two from 1992 to 2000.26
Nevertheless, the hardiness and lethality of anthrax spores has long suggested their potential as agents of germ warfare, and numerous countries worked on secret anthrax bioweapons projects during the Cold War. Much of what is known about weapons-grade anthrax comes from studies of a single epidemic in the former Soviet Union in 1979. When the Soviet state collapsed, scientists were able to trace the epidemic to an accidental release of an aerosol of anthrax spores from a nearby germ weapons factory. Nearly all of the unlucky people and animals who developed the disease were downwind of the factory when the plume of invisible spores blew over.27 Even before the U.S. anthrax mailings in 2001, experts on bioterrorism understood that anthrax is simple to grow, is durable, and is suitable for many forms of delivery, and that many countries had stockpiled spores: “The long-dreaded concern that chemical and biological weapons might reach terrorist hands is now a reality.”28 The United States worked on inhalation anthrax during the Cold War, and although it and numerous other countries signed a treaty in 1993 against this use, at least 10 countries are thought to be working on such projects. Ironically, because the spores mailed in 2001 were weapons-grade, some experts suspected they must have come from a U.S. military insider eager to demonstrate the need for more research on biological weapons. They were proven correct after a long, poorly handled investigation.29
The effects were devastating. During the following year, health officials logged 22 cases of anthrax caused by the mailings, among them five deaths. They investigated hundreds of reports of possible exposure and closed several government buildings to clear them of spores. As political commentator Daniel Greenberg explained, it had taken a “malevolently brilliant [attack] ideal to reach the ears and fears of the public.” The attack focused attention