[GH85Carrera]

Two 13-year-old boys caught smallpox at the same time in 1910.
One had been vaccinated as a child and he developed only mild symptoms, with just a few scabs that healed quickly. The other, unvaccinated, suffered the full, severe form of the disease, which could be disfiguring or deadly.
English physician Edward Jenner developed the first smallpox vaccine back in the late 1700s after discovering that exposure to cowpox could protect people from smallpox. Still, despite clear proof that it worked, anti-vaccine movements existed even then, spreading fear about side effects and even outlandish rumors that people might turn into cows, since the vaccine came from cowpox.
Smallpox was finally eradicated globally in 1980.