I remember noticing a distinct scar on my mother’s shoulder as a child—a ring of small indents around a larger one. At the time, it fascinated me, though I later forgot about it. Years later, I saw the same scar on an elderly woman and asked my mother about it again. She explained it was from the smallpox vaccine.
Smallpox was a deadly viral disease, killing about 30% of those infected and leaving many disfigured. Thanks to widespread vaccination, it was declared extinct in the U.S. by 1952, and routine vaccinations stopped in 1972. Before then, all children were vaccinated, leaving behind a distinctive scar—a kind of early “vaccine passport.”
The scar forms because the vaccine was delivered with a two-pronged needle, creating multiple punctures. The virus in the vaccine caused bumps that developed into fluid-filled blisters, which scabbed over, leaving the familiar mark.