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Certain vaccines, such as the Bacillus Calmette–Guérin (BCG) vaccine, leave a characteristic round scar.
These scars form because the injection creates a localized immune response in the skin, leaving a small circular mark once healed.
The BCG scar is usually slightly raised and darker than surrounding skin.
2. Bug Bites or Skin Infections
Insect bites, like those from mosquitoes or spiders, can sometimes leave small, round scars, especially if scratched excessively.
Localized skin infections, such as boils or abscesses, can also heal with a circular scar.
Healing depends on how the wound was treated and whether infection was prevented.
3. Medical Procedures
Minor medical procedures like mole removal, cyst excision, or immunotherapy shots can leave small round scars.
The scar size is typically proportional to the size of the intervention.
Proper post-procedure care often reduces the prominence of the scar.
4. Skin Conditions
Conditions like chickenpox or localized skin cysts can result in circular scars after the lesions heal.
Scars may be flat, depressed, or slightly raised depending on the severity of the initial lesion.
Why These Scars Form
When the skin is injured, the body begins a natural healing process:
Inflammation: Blood and immune cells rush to the site to prevent infection.
Tissue Formation: New collagen is laid down to repair the wound.