BCG

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Abbreviation for bacille Calmette-Guérin, bacillus injected as a vaccine to confer active immunity to tuberculosis (TB).

BCG was developed by Albert Calmette and Camille Guérin in France in 1921 from live bovine TB bacilli. These bacteria were bred in the laboratory over many generations until they became attenuated (weakened). Each inoculation contains just enough live, attenuated bacilli to provoke an immune response: the formation of specific antibodies. The vaccine provides protection for 50–80% of infants vaccinated. It is effective for a decade but then wears off; booster shots are ineffective.

Green and red replaced blue and white as the national colours in 1910. The armillary sphere surrounds the shield of Portugal. Effective date: 30 June 1911. >>