In this picture, Edward Jenner vaccinates a reluctant patient with cowpox matter to prevent the more serious smallpox. Meanwhile, those already vaccinated show many, er, unusual side effects from the process. Previously innoculations for smallpox involved cutting the skin and using actual smallpox matter. It was called variolation and was much riskier. The word vaccine comes from Jenner’s method and takes its name from “vacca,” the Latin word for cow. Then as now, new developments could be met with skepticism.