A smallpox vaccine scar is a distinctive mark that smallpox vaccination leaves behind.
The scar may be round or oblong, and it may appear deeper than the surrounding skin. Usually, the scar is smaller than the diameter of a pencil eraser, though it can be larger.
In some people, smallpox vaccination scars are itchy or uncomfortable. This is part of the body’s normal response to scarring.
A scar forms in response to an injury, such as the puncture involved in smallpox vaccination. As the body repairs the damage, it forms scar tissue.
In most people, this scar tissue is small. However, some people experience an inflammatory response to the injection of the vaccine, which can lead to a larger, raised scar.
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