BCG acronym for Calmette-Guérin bacillus, which produces anciently terrifying and deadly tuberculosis. ( TB ) . Today the BCG vaccine is applied at discretion and under certain standards, especially to health workers. In countries with TB, mass vaccination of children under 5 years of age is used. A tuberculin skin test may then be done, which can come out positive, either by the effect of the vaccine itself or because the person has contracted the disease. Some synonyms, words or similar expressions may be bacillus of calmette guérin