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 What is BCG Vaccination?
Can BCG Prevent
TB in HIV- Positive Individuals?
Is BCG Safe in
Children with HIV/AIDS?
How effective
is BCG in General?
What is BCG vaccination?
Bacille Calmette Guerin (BCG) is a
live vaccine derived from an attenuated strain of M. bovis
and is named after the two doctorsCalmette and
Guerin who discovered it. BCG is effective in preventing disseminated form of
TB in children-, efficacy is debatable against adult
forms of TB. 
Can
BCG prevent TB in HIV- positive individuals?
BCG
cannot be expected to prevent TB in HIV-positive individuals since HIV
infection is usually acquired by young adults. As BCG is mainly given at
birth in developing countries, the immunity from it wanes by the age of young
adult; BCG cannot protect against the exogenous re-infection of TB in adults.
Is BCG safe In
children with HIV/AIDS?
BCG
is not safe in individuals with AIDS because of the risk of disseminated BCG
disease. Presently, WHO and UNICEF recommend that, for asymptomatic
HIV-infected children living in
Areas
where the risk of tuberculosis is high, BCG still be
given at birth or as soon as possible thereafter in accordance with standard childhoodimmunization policies, but that it be withheld
in infants thought to have symptomatic HIV-infection.
How effective is BCG in general?
The
effectiveness of BCG in general, particularly in developing countries where
it is given at birth or less than one year of age, is limited to protection
against the severe forms of TB in children. The degree of effectiveness
varies between 0 and 80% but the vaccine is unable to prevent most contagious
forms of TB in adults.
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