What the small round scar on your arm might indicate

That Small Round Scar on Your Upper Arm Could Be a Sign of an Old Vaccine

I didn’t think much about it as a kid—just a small, round mark on my mom’s upper arm that looked a little different from the usual scrapes and bruises. Then years later, in a completely unrelated moment, I noticed the same circular scar on an older woman as I helped her step off continue reading …