Smallpox was a highly contagious disease that affected millions of people throughout history, causing severe scarring, blindness, and even death. For centuries, there was no effective treatment for smallpox, and outbreaks turned quickly into devastating epidemics. On May 14, 1796, the smallpox vaccine was finally developed.
In the late 18th century, a British physician named Edward Jenner observed that milkmaids who had contracted a mild disease called cowpox seemed to be immune to smallpox (1). He hypothesized that exposing people to cowpox could protect them from smallpox and set out to test his theory.
Jenner conducted a series of experiments on volunteers, including his own son. He collected pus from cowpox lesions on the hands of milkmaids and used it to inoculate healthy individuals. He found that the inoculated individuals developed a mild form of cowpox but did not contract smallpox when exposed to the disease.
Jenner named his discovery “vaccination,” derived from the Latin word for cow, “vacca.” His method of vaccination became widely accepted and was instrumental in eradicating smallpox from the world.
The development of the vaccine was a significant scientific breakthrough that paved the way for the development of modern immunization techniques. Vaccines work by introducing a weakened or inactivated form of a disease-causing pathogen into the body, triggering the immune system to produce antibodies that can fight off the disease. This process creates immunity without causing the disease itself (2).
In 1980, the World Health Organization (WHO) declared that smallpox had been eradicated from the world thanks to the global vaccination campaign. This was the first time in history that a human disease had been eradicated (3).