Tuberculosis Bacille Calmette-Guerin vaccine

Bacille Calmette-Guerin Vaccine (BCG). The BCG vaccine is an attenuated, hybridized strain of M. bovis. It was developed in 1921 and is used as a prophylactic vaccine against TB. Administration of BCG vaccine is compulsory in many developing countries and is officially recommended in many others. Vaccination with BCG produces a subclinical infection resulting in sensitization of T-lymphocytes and cross-immunity to M. tuberculosis, as well as cutaneous hypersensitivity and, in many cases, a positive tuberculin skin test. 

Bacille Calmette-Guerin (BCG) A vaccine prepared from a living attenuated strain of tubercle bacilli and used to vaccinate human beings against tuberculosis or treat some types of cancer. 

This vaccine is routinely given to infants and small children in countries where TB is common. This vaccine contains a live attenuated (weakened) strain of Mycobacterium tuberculosis, the bacterium which causes tuberculosis. The bacterium has been modified to produce a strain known as Bacille Calmette-Guerin, named after its discoverer. Killed vaccines (strain) can not be used to protect against tuberculosis infection since they do not produce the necessary cellular immune response. 

Clinical Use. Bacille Calmette-Guerin (BCG, TheraCys, others) is an active bacterial strain that can be administered systemically as a vaccine against tuberculosis. This agent may also stimulate immune function and can be administered locally within the bladder (intravesicularfy) to treat certain forms of superficial bladder cancer.66... 

Tuberculosis. Recent experimental evidence suggests that exposiue to Mycobacterium tuberculosis may reduce the risk of developing asthma. In a partly longitudinal study of children in Japan, an inverse relationship was found between tuberculin skin response, allergen-specific IgE and symptoms of asthma. However it is unclear whether Bacille Calmette Guerin (BCG) vaccination, primary tuberculous infection in childhood, or sensitisation to harmless environmental mycobacteria were responsible [155(111)]. (BCG vaccination is discussed below under Immunisation .)... 

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