In 1721 Dr. Zabdiel Boylston vaccinated his six-year-old son and two servants against smallpox. These were the first vaccinations given for the disease in the United States.
- Smallpox is a contagious disease caused by the variola virus.
- Smallpox was the first disease to be eliminated from the world through public-health efforts and vaccination.
- Smallpox still poses a threat because existing laboratory strains may be used as biological weapons.
- Smallpox causes high fever, prostration, and a characteristic rash. The rash usually includes blister-like lesions that occur everywhere on the body.
- Approximately one-third of people with smallpox died from the disease. Survivors were scarred for life. If the eye was infected, blindness often resulted.
- There are new experimental medications that might be effective in smallpox, but these have not been tested in human cases since the disease has been eradicated.
- The smallpox vaccine contains a live virus called vaccinia. It is administered by dipping a pronged piece of metal into the vaccine and then pricking the skin.
- The vaccine has uncommon side effects that may be fatal, including infection of the heart and brain with the vaccinia strain. Serious side effects are more common with the initial vaccine and are uncommon with second doses.
- The vaccine is currently only given to selected military personnel and laboratory workers who handle the smallpox virus.
Smallpox is thought to have existed for more than 12,000 years. Evidence of infection can be found in mummies from ancient Egypt, including the mummy of Ramses V. Smallpox entered the New World in the 16th century, carried by European explorers and conquistadors. Because the aboriginal inhabitants had no immunity to the disease, smallpox often decimated native populations. There are even reports where infected blankets were used to intentionally infect Native American populations in the 18th century — one of the early examples of biological warfare. During the 20th century, it is estimated that there were 300 million to 500 million deaths from smallpox worldwide, compared to 100 million from tuberculosis.
Currently, the risk factors are working in highly specialized laboratories that may still have smallpox viruses in storage by accident or become contaminated while either working with the viruses or using the viruses as a biological weapon. Continue Reading