Tuberculosis (TB) kills or debilitates more adults aged between 15 and 59 years than any other disease in the world. TB is caused by Mycobacterium tuberculosis, an intracellular pathogen of the genus Mycobacterium that includes some 55 species, half of which may cause disease in humans.
BCG Vaccines (Tuberculosis)
In order to prevent further deviation from the original BCG, lyophilized seed lots of the vaccine strains have been kept by WHO since 1956. Vaccine strains are prepared from seed-lot material by growing the bacilli in an artificial medium, harvesting, concentrating, homogenizing, and the preparation is then lyophilized.
BCG Vaccine Standardization
WHO adopted requirements for BCG vaccine in 1965 and these were updated in 1978 to reflect the increased knowledge concerning the dose of vaccine to administer and the change to freeze-dried preparations. These were modified slightly in 1985 to update production and testing requirements, and amended again in 1987 to amend requirements concerning the expiry date.
Recommendations to assure the quality, safety and efficacy of BCG vaccines, Annex 3, Technical Report Series 979
WHO reference materials for BCG vaccine, BCG vaccine substrains (Tokyo 17, Danish 1331 and Russian BCG-I) are available to qualified applicants:
WHO Informal Consultation on Standardization and Evaluation of BCG Vaccines, 22-23 September 2009, WHO, Geneva, Switzerland
WHO discussion on the improvement of the quality control of BCG vaccines, Pasteur Institute, Paris, France, 7 June 2005
WHO Consultation on the characterization of BCG vaccines, WHO, Geneva, Switzerland, 8-9 December 2004
WHO Consultation on the characterization of BCG strains, London, UK, 15-16 December 2003
Prequalified BCG vaccines
BCG vaccines are prequalified for procurement by UN organizations: