Vaccines: 200 years of progress - and scepticism

Deadly and highly contagious smallpox, transmitted through open sores that scarred millions for life, ravaged populations for centuries until English doctor Edward Jenner notices that milkmaids who got cowpox never get smallpox.

source https://timesofindia.indiatimes.com/world/europe/vaccines-200-years-of-progress-and-scepticism/articleshow/79620077.cms