Scourge: The Once And Future Threat of Smallpox

Smallpox, the only infectious disease to have been eradicated, was one of the most terrifying of human scourges. It covered the skin with hideous, painful boils, killed a third of its victims, and left the survivors disfigured for life. In this riveting, often terrifying look at the history of smallpox, Jonathan B. Tucker tells the story of this deadly disease, the heroic efforts to eradicate it worldwide, and the looming dangers it still poses today.

Jonathan B. Tucker is an expert on biological and chemical weapons in the Washington, D.C., office of the Monterey Institute of International Studies.

Chapter One

MONSTER ON DEATH ROW

    In a maximum-security facility in Atlanta, the world's most dangerous prisoner sits in solitary confinement, awaiting execution. Wanted for the torture and death of millions of people, this mass murderer was captured in a global dragnet lasting more than a decade. Although the prisoner has been condemned to death, the jailers are debating whether or not to carry out the sentence. Some believe that studying the killer's methods could help to develop better defenses against such crimes, yet others fear that the prisoner could escape and wreak mayhem on an even greater scale. While the debate continues, the execution has been postponed.

    The world's most dangerous prisoner is the smallpox virus, and it is held inside two padlocked freezers in a secure room at the U.S. Centers for Disease Control and Prevention in Atlanta. Some 450 samples of the virus in neatly labeled, half-inch plastic vials are arrayed on metal racks and immersed in a bath of liquid nitrogen that keeps them deep-frozen at -94 degrees Fahrenheit. Access to the smallpox repository requires two sets of keys controlled by different people; closed-circuit television cameras and electronic alarm systems maintain continuous surveillance. A second set of smallpox virus stocks lies in a similar vault at a Russian laboratory in Siberia.

    The scientific name for the smallpox virus is variola, the diminutive of the Latin word varius (spotted) or varus (pimple). Consisting of little more than a set of genetic instructions in a long ribbon of DNA, coiled up inside a biscuit-shaped protein shell, the variola virus cannot grow or metabolize and has no means of locomotion. Its sole function is self-replication, which it accomplishes by entering human cells and commandeering their biochemical machinery to churn out more virus particles. When variola existed in the wild, it came in two distinct varieties: Variola major caused a serious disease that killed between 10 percent and 30 percent of its victims, whereas variola minor gave rise to a much milder illness called alastrim, with a case mortality rate of less than 1 percent. Because the two types of smallpox virus produced similar symptoms, it is not known why one was so much more lethal than the other.

    Now confined to a few laboratory freezers, variola major once rampaged through the human species and caused the most feared of deadly scourges. After a two-week incubation period, smallpox racked the body with high fever, headache, backache, and nausea, and then peppered the face, trunk, limbs, mouth, and throat with hideous, pus-filled boils. Patients with the infection were in agony--their skin felt as if it was being consumed by fire, and although they were tormented by thirst, lesions in the mouth and throat made it excruciating to swallow. The odor of a smallpox ward was oppressive: The rash gave off a sweetish, pungent smell reminiscent of rotting flesh. For those who survived, the disease ran its course in a few weeks. Pustule formation concluded on days eight to ten of the illness, after which the boils scabbed over and were gradually reabsorbed. On days fifteen to twenty, the crusty dry scabs separated and fell off, leaving depigmented areas of skin that later turned into ugly, pitted scars.

    Even as smallpox victims were suffering the torments of the disease, they were spreading it to others. Lesions in the patient's mouth and throat shed millions of virus particles into the saliva and mucus, so that talking or sneezing expelled virus-laden droplets that floated in the air and could be inhaled. The virus was also present in patients' urine and in pus from unhealed skin lesions. When clothing and bed linens contaminated with dried pus were handled, virus particles could be resuspended in the air, so that laundry workers who washed the sheets and blankets of smallpox patients were at great risk of infection. The corpses of smallpox victims were also dangerously contaminated and could spread the disease to undertakers or to family members who prepared a loved one's body for ritual burial.

    Over the course of human history, smallpox claimed hundreds of millions of lives, far more than plague--the dreaded Black Death of the Middle Ages--and all the wars of the twentieth century combined. Although those lucky enough to survive a bout with smallpox acquired lifelong immunity, they usually suffered some type of permanent damage. Nearly all were disfigured with pockmarks, and one in ten was rendered partially or completely blind. Smallpox often caused miscarriage in pregnant women and stunted the growth of young children.

    As recently as 1967, the disease sickened between ten million and fifteen million people each year in forty-three countries and caused an estimated two million deaths. On May 8, 1980, however, the World Health Organization (WHO) declared that humanity had finally been freed from the torments of smallpox, the culmination of a global campaign lasting more than a decade and employing up to 150,000 health workers at various times. The conquest of smallpox, the first--and so far, only--infectious disease to have been eradicated from nature by human effort, was among the greatest medical achievements of the twentieth century.

    After the WHO formally certified the eradication of smallpox in May 1980, all member countries agreed to stop vaccinating their civilian populations because the potential risk of complications from the vaccine now outweighed the tiny chance that smallpox might re-emerge from natural sources. Since then, the horrors of the disease have faded from public consciousness like the memory of a nightmare. Fewer and fewer individuals bear the round, mottled scar of a smallpox vaccination on their upper arm or thigh, let alone the disfiguring pockmarks that were once the hallmark of the disease. But although some would relegate the history of smallpox to the dusty shelves of a medical library, such complacency would be premature. In 1992, a senior Russian official defected to the United States and told the CIA that the Soviet Union, even as it had supported the smallpox eradication campaign with vaccine and expertise, had secretly developed the virus into a military weapon and stockpiled enough of it to kill millions of people. News of the Soviet betrayal sparked official concern in Washington, London, and other capitals that samples of the virus might fall into the hands of "rogue" states and terrorist organizations.

    Because the immunity induced by the smallpox vaccine fades after about a decade, most of the world is now susceptible to infection. Responding to this potential threat, the United States and other countries are undertaking urgent efforts to strengthen their medical defenses against this supposedly eradicated disease. Every human being on the planet has a stake in the fate of the smallpox virus, for we are all ultimately at risk.

Excerpted from Scourge by Jonathan B. Tucker. Copyright © 2001 by Jonathan B. Tucker. Excerpted by permission. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.