The BCG vaccine, which stands for Bacille Calmette-Guérin, is a live attenuated vaccine used primarily to prevent tuberculosis (TB). It’s a single-dose vaccine, typically administered to infants in countries with high TB prevalence. BCG offers protection against severe forms of TB, like meningitis and disseminated TB, particularly in children.
Purpose: Primarily to prevent tuberculosis (TB) in children and individuals at high risk. Administration: Usually given as a single dose intradermally (between the layers of skin) on the upper arm of infants. Effectiveness: BCG is most effective against severe forms of TB, like meningitis and disseminated TB, but less effective in preventing lung TB. Side effects: Common side effects include a local reaction at the injection site, which may include a small pustule and scar. More serious reactions, such as lymphadenitis, abscesses, or severe ulcerations, are rare but can occur.
BCG SCAR
A small scar is expected at the BCG vaccine injection site, and it’s a sign that the vaccine has taken effect. This scar is often used as evidence of previous vaccination. The scar typically appears as a red, raised bump that may weep or ooze before crusting over and leaving a small, permanent scar.
Here’s a more detailed explanation:
Normal Development: After the BCG vaccine, a red, raised bump may appear at the injection site within 1-6 weeks. This bump may then turn into a small, weeping sore, which can take up to 3 months to heal. Scar Formation: The sore will eventually heal, leaving a small, permanent scar, which is a normal response to the vaccine.
Sign of Protection: The presence of a BCG scar indicates that the vaccine has been effective and is a marker of successful vaccination.
Clinical Use: The scar can be used to verify previous vaccination, especially in areas where vaccination records might not be readily available, according to the National Institutes of Health (NIH).
Aftercare: Keep the area clean and dry, and avoid covering it with plastic dressings or ointments.
Scar Size: The mean scar diameter can vary, with studies reporting an average of around 3-4mm.
Variations: While a scar is generally expected, not all individuals will develop one. Factors like the strain of the vaccine, the administrator, and the age of administration can influence scar formation.
