What That Small Round Scar on Your Arm Really Means
The small, circular scar that often appears on the upper arm is commonly mistaken for a childhood injury, insect bite, or skin condition. In reality, it is most often the result of the Bacillus Calmette-Guérin (BCG) vaccine, which is administered to protect against tuberculosis (TB). Unlike many modern injections, the BCG vaccine uses a weakened…