On October 2, 1980, a 47-year-old woman from south lake Tahoe, California, lost her 9-month-old pet cat to an acute infection. Three days later, the woman's own temperature shot up, but she still went to her job at a day-care center. The fever worsened; she developed chest pains and shortness of breath. Two days later she drove herself to the hospital. The diagnosis was pneumonia, and she was treated with tetracycline. Shortly afterward the woman died.
Not until four days later did anyone realize that the woman had died of plague. Fearing that treatment might arrive too late, doctors rushed prophylactic antibiotics to the children and staff at the day-care center. Luckily, no one exposed to the woman fell ill. In this country, we tend to think that the horrors of plague are confined safely to the past. Plague, the black death, burned through the medieval world of Europe, killing about one of every four people. But by the mid-18th century, epidemic plague had died down. The terrible days of deserted cities and heaps of the dead fell into the dim past on the Continent, although plague never disappeared—more than 10 million died of it in India less than a century ago.
Plague's current sluggishness poses a number of questions: How could a disease that does not seem to be highly contagious, as evidenced by the story of the woman who worked at the day-care center, slaughter millions in a short period of time? Why does plague move from a smoldering to an explosive phase, and back again? And most important, is it possible that epidemic plague could return?
For biodefense experts the questions are serious, but they are not always about plague. "To Russian and American scientists, plague and anthrax seem like mirror images of one another. We worry about anthrax; they worry about plague," says Paul Keim, a molecular biologist at Northern Arizona University who specializes in the DNA fingerprinting of dangerous pathogens. Keim says anthrax terrifies our scientists more than plague because anthrax spores remain indestructible for long periods of time. A bioterrorist attack with anthrax could render an area infective for generations.
