Medical Q&As

BCG - not vaccinated?

My daughter is 18 and she did not have BCG vaccination as a child. She is about to begin studying medicine abroad and must have proof of vaccination against TB before commencing her studies. Can she be vaccinated now as an adult, and if so, where?

BCG (Bacille Calmette Guerin) vaccination is used to protect against TB. Since your daughter is about to embark upon the study of medicine it is most important that she be adequately protected against this potentially serious disease. During the course of her medical studies it is highly likely that she will come in contact with several cases of TB and she would be at risk of acquiring this disease if she were not protected. She is not too old to be vaccinated but prior to receiving the vaccine it is likely that she will first undergo a special test called the Mantoux test. This test involves the injection of a small amount of tuberculin protein into her skin. The injection site is then inspected a couple of days later to ascertain if her immune system has reacted against the protein. If the test result is negative it indicates that she has not been exposed to TB. In that situation she would be given the BCG vaccine. However, the interpretation of a positive test is less straight forward. The test is positive in those individuals who have received BCG vaccine as well as those that have been exposed to TB in the past or present. Since your daughter has not been vaccinated with BCG she would need to be assessed further. However, the overwhelming balance of probability is that your daughter will have a negative test result and will be given the BCG vaccine. BCG is usually administered through health board clinics on certain days of the month. Your local health board office or clinic will be able to advise you when the next clinic will be taking place. BCG is not available through your GP.