What is BCG?

What is BCG?

The little round scar on your left upper arm – your BCG (Bacillus Calmette-Guerin) vaccination – will not stop you from being infected with tuberculosis (TB) as an adult. BCG is a vaccination used to prevent tuberculosis in children, referred to as BCG, which is made using live, non-toxic bovine tuberculosis.

Mycobacterium tuberculosis can attack other organs, including your brain, which we call meningitis TB. After vaccination, it can prevent the occurrence of childhood tuberculosis, especially those serious types of tuberculosis, such as tuberculous meningitis.

Uses of BCG

BCG vaccination can make the body resistant to tuberculosis to prevent tuberculosis. Infants and young children have the weakest resistance. If they are infected with tuberculosis bacteria, they are prone to acute tuberculosis, such as tuberculous meningitis, which is life-threatening.

Therefore, since 1961, all newborns in Malaysia have been given the BCG vaccine almost immediately after being born. In primary school, nurses will check the pupils’ upper left arm and if there is no BCG scar, they will revaccinate the children.

The World Health Organization (WHO) study confirmed that the average effective rate of BCG vaccination against tuberculous meningitis and disseminated tuberculosis is 86%; the effective rate of preventing tuberculosis-related deaths is 65%, and the effective rate of preventing tuberculous meningitis deaths is 64%, the effective rate of preventing disseminated tuberculosis death is 78%. Over the years, vaccination with BCG has saved thousands of lives.

BCG vaccination time

The main purpose of vaccination is to enable people who are not infected with tuberculosis bacteria to receive an artificial infection with attenuated tuberculosis bacteria in order to obtain artificial immunity against tuberculosis bacteria and prevent the onset of disease. Therefore, tuberculin-negative persons are the only targets.

According to national literature reports, the BCG vaccination time is generally within 24 hours after your baby is born or at the age of seven to prevent you from getting deadly forms of TB infections which children are at high risk of.

BCG vaccination response

After BCG vaccination, some children will develop reactions such as papules at vaccination sites that may occur in 2-6 weeks. This grows and flattens with scaling and crusting. Occasionally, a discharging ulcer may occur. This will heal leaving a scar of at least 4 mm.

What to do if the lymph gland is enlarged after BCG vaccination

Lymph node inflammation in the neck, underarms, clavicle, etc. may occur around 1-2 months after vaccination and can be treated with hot compresses. If there is lymphadenopathy within three months of BCG vaccination, you can continue to observe; if you still have swelling after three months and the reaction is too strong, you should go to the tuberculosis prevention and treatment center. It will gradually disappear after a period of time and does not require surgical treatment.

References

Loh, A., Xian, L., & Hilmy, I. (2019, September 19). BCG unable to Prevent TB in adults. Retrieved February 15, 2021, from https://www.thestar.com.my/news/nation/2019/09/19/bcg-unable-to-prevent-tb-in-adults
Paediatric Protocols for Malaysian Hospitals, 4th Edition, 2019 [Updated]