BCG or bacille Calmette-Guerin is a vaccine for tuberculosis (TB) disease which is caused by Mycobacterium tuberculosis.
Symptoms of TB disease depend on where in the body the TB bacteria are growing. TB bacteria usually grow in the lungs (pulmonary TB) which may cause symptoms such as a bad cough that lasts 3 weeks or longer, pain in the chest, coughing up blood or sputum (phlegm from deep inside the lungs). Other symptoms of TB disease are weakness or fatigue, weight loss, no appetite, chills, fever, sweating at night.
People infected with TB bacteria have a lifetime risk of falling ill with TB of 10%. However, persons with compromised immune systems, such as people living with HIV, malnutrition or diabetes, or people who use tobacco, have a much higher risk of falling ill. Tuberculosis infection can cause complications such as joint damage, lung damage, infection or damage of your bones, spinal cord, brain, or lymph nodes, liver or kidney problems and inflammation of the tissues around your heart which may turn fatal.
BCG vaccine can protect about 50% of recipients against TB of the lungs. People who are vaccinated may also become sick with TB, but 80% of them are still protected from life threatening forms of disease such as miliary disease and meningitis. Vaccination in earlier childhood improves the chances of prevention.
The Indian Academy of Pediatrics (IAP) & Centers for Disease Control and Prevention (CDC) strongly recommend children receive all vaccines according to the recommended Vaccination schedule.