top of page

Smallpox is still the only disease completely eradicated by vaccination efforts

Children holding their vaccination certificate in Cameroon | Robert J. Baldwin

The smallpox vaccine recently came back into public focus when it was revealed that it was effective at controlling monkey pox, a disease that had been making international headlines during a lull amidst the global COVID-19 pandemic. It's interesting to note that smallpox is the only disease ever to be completely eradicated in the wild by humans. The U.S. military still stocks the vaccine because the smallpox virus is still in storage in a few military and scientific laboratories.

What is smallpox?

Smallpox is a highly contagious and deadly disease caused by the variola virus. It is characterized by a fever and a distinctive rash that spreads over the body. The rash begins as small red spots that develop into raised bumps that eventually fill with pus and then crust over. The disease can cause severe complications, including blindness, encephalitis (inflammation of the brain), and death. Smallpox was responsible for countless deaths throughout history, particularly before the development of a vaccine in the 18th century.

It was a disease that affected people worldwide and was responsible for several devastating pandemics in the past.

Cow pox and monkey pox are milder viruses that are closely related to smallpox. They all belong to the orthopoxvirus family of viruses.

How was the smallpox vaccine developed?

The first smallpox vaccine was developed by Edward Jenner in 1796. Jenner observed that milkmaids who had contracted cowpox, a disease similar to smallpox but less severe, did not contract smallpox. He hypothesized that cowpox provided immunity to smallpox and tested his theory by injecting a boy with material taken from a cowpox blister. The boy did not contract smallpox when he was later exposed to it. Jenner's vaccine was made by infecting a person with cowpox and then using the material from the resulting blister to infect another person. Over time, the vaccine was refined and made safer, eventually leading to the global eradication of smallpox in 1980.

How was smallpox eradicated?

Smallpox was eradicated through a global vaccination campaign led by the World Health Organization (WHO). The campaign began in 1967 and used the smallpox vaccine, which had been in use for over 150 years, to protect individuals from contracting the disease. The strategy for eradication involved mass vaccination of the population and isolation and vaccination of individuals who had been in contact with smallpox cases. The campaign was successful in stopping the spread of smallpox and reducing the number of cases. By the 1970s, smallpox was only present in a few countries in Africa and Asia. In 1977, the WHO launched a "Final Push" to eradicate the disease completely. This involved increasing the number of vaccination teams and focusing on the remaining areas where smallpox was still present. In 1980, the WHO declared that smallpox had been eradicated, making it the first disease to be eradicated by human effort.

Concluding thoughts

The success of the smallpox eradication campaign has been credited to a combination of factors, including the effectiveness of the vaccine, the coordination of the global effort, and the ability to quickly isolate and contain outbreaks. For future eradication efforts to be successful, we need continuing public support and cooperation throughout the world. Unfortunately, trust in vaccines and trust in public health projects in general is one the wane so we will likely see the resurgence of some terrible diseases like polio--but hopefully not smallpox!


bottom of page