The Truth About the Scar on Your Upper Left Arm

Many of us have a small, round scar on our upper arms as a result of the smallpox vaccine, which was common prior to the 1970s. This vaccination used live Vaccinia virus to stimulate an immune response to the lethal Variola virus, which causes smallpox.

It used live Vaccinia virus in order to trigger an immune response that would protect people against the dangerous Variola virus that caused smallpox. After the vaccination, blisters forms at the vaccination area, crusted over, and healed in a couple of weeks.

“After receiving the shot, blisters appear at the injection site, which eventually heal and leave a circular scar,” according to the beginning of the article.

The scars are apparent because each needle puncture provided a dose of the vaccination, resulting in blisters. The injection site expands slightly after the shot before returning to normal. However, 6 to 8 weeks later, a lump resembling a mosquito bite develops into a tumor. It later opens, exudes fluid, and develops into an ulcer before mending into an indelible scar.

Smallpox was eradicated in most of the Western world by the early 1970s, and immunizations were discontinued in the 1980s due to a lack of exposure to the Variola virus. The scar serves as a historical record of a once-dangerous disease.