The first vaccine, which was designed to protect against the disease of smallpox, was developed in the 1700s when no one had knowledge of the workings of the immune response. Thanks to keen observations by scientists and physicians like Edward Jenner, as well as the fortuitous antigenic similarity between the cowpox virus and the smallpox virus, material from cowpox sores was used as a vaccine to prevent smallpox. Almost 200 years later (in 1980), smallpox became the first disease to be eradicated globally due to worldwide intense efforts at vaccination. Below is a brief timeline of some of the historical highlights of vaccine development.