The skin is punctured multiple times in a single spot, typically on the upper arm. This intentionally creates a small, localized infection—not with smallpox itself, but with a related, much milder virus called *vaccinia*—which prepares the immune system to fight the actual disease. Over the following 14–21 days, the area would blister and scab over before healing, leaving behind the small, round, slightly indented scar that many people recognize. Key takeaways:
The scar originates from the traditional method of administering the smallpox vaccine: a bifurcated needle was used to
