The eradication of smallpox is one of the great success stories of modern medicine. As the clinical memory of smallpox fades from the imagination of both the public mind and the medical community, it is helpful to recall that in many ways even its distant past remains shrouded in mystery.
While it has been almost 40 years since the last known case of smallpox, the impact of this disease on the world population can hardly be overstated. In medieval Europe, it is estimated that almost a half million people died annually from this scourge, and survivors were left with a variety of permanent sequelae, including scarring and blindness.1