Smallpox vaccine Smallpox vaccine Smallpox vaccine, the first successful vaccine to be developed, was introduced by Edward Jenner in 1796. He followed up his observation that milkmaids who had previously caught cowpox did not later catch smallpox by showing that inoculated cowpox protected against inoculated smallpox. Dryvax is a freeze-dried calf lymph smallpox vaccine. It is the world's oldest smallpox vaccine, created in the late 19th century by American Home Products, a predecessor of Wyeth. By the 1940s, Wyeth was the leading US manufacturer of the vaccine and the only manufacturer by the 1960s. After world health authorities declared smallpox had been
Ring vaccination again, to the contacts' contacts. When responding to a possible outbreak, health officials should consider which is best, ring vaccination or mass vaccination. In some outbreaks, it might be better to only vaccinate those directly exposed; variable factors (such as demographics and the vaccine that is available) can make one method or the other safer, with fewer people experiencing side-effects when the same number are protected from the disease. Ring vaccination was used in the eradication of smallpox. It was also used experimentally in the Ebola virus epidemic in West Africa. In 2018, health authorities used a ring vaccination strategy