is an acute contagious disease caused by variola virus, a member of the
orthopoxvirus family. Smallpox, which is believed to have originated over 3.000
years ago in
In some ancient cultures, smallpox was such a major
killer of infants that custom forbade the naming of a newborn until the infant
had caught the disease and proved it would survive. Smallpox killed Queen Mary
The disease, for which no effective treatment was ever
developed, killed as many as 30% of those infected. Between 65–80% of survivors
were marked with deep
pitted scars (pockmarks), most prominent on the face. Blindness was another
complication. In 18th century
As late as the 18th century, smallpox killed every
10th child born in
In the early 1950s – 150 years after the introduction of vaccination – an estimated 50 million cases of smallpox occurred in the world each year, a figure which fell to around 10–15 million by 1967 because of vaccination. In 1967, when WHO launched an intensified plan to eradicate smallpox, the "ancient scourge" threatened 60% of the world's population, killed every fourth victim, scarred or blinded most survivors, and eluded any form of treatment.
Mass vaccination programs were successful in many Western countries; however, a different approach was taken in developing countries. This approach was known as surveillance and containment. Surveillance was aided by extensive house-to-house searches and rewards offered for persons reporting smallpox cases. Containment measures included ring vaccination and isolation of cases and contacts. Hospitals played a major role in transmission in a number of smallpox outbreaks.
Through the success of the global eradication
campaign, smallpox was finally pushed back to the horn of
A fatal laboratory-acquired case occurred in the
The WHO Orthopoxvirus Committees meeting in 1994 and
1999 have recommended that no one other than the two WHO collaborating centres
The World Health Organization is currently supporting several control programs and has not singled out another disease for eradication. The lessons learned from the smallpox campaign can be readily applied to other public health programs.
The WHO factsheet on smallpox.