Smallpox, a deadly viral infection, caused severe fever and skin rashes, claiming 3 out of 10 lives and leaving survivors with scars. The variola virus was responsible, and scientists developed a vaccine using the related vaccinia virus. This vaccine spurred immune responses that led to smallpox’s eradication by the early 1950s. A smallpox vaccine scar, often round or oblong, resulted from an invasive bifurcated needle used to deliver the vaccine. This method caused scabbing, and as the body healed, a noticeable scar remained, marking the immune response to the vaccine
