Interventions for Tuberculosis Control and Elimination 2002
Interventions for Tuberculosis Control and Elimination 2002
Interventions for Tuberculosis Control and Elimination 2002
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BCG re-vaccination<br />
It is or has been the policy in many countries to re-vaccinate with BCG at<br />
school entry or later in life. There is no evidence that this increases protection<br />
against tuberculosis, 723,837,838 but in northern Malawi it has been<br />
shown to considerably increase protection against leprosy. 777 Re-vaccination<br />
schemes often fall into the lowest tuberculosis risk period in life (age<br />
five to 14 years) <strong>and</strong> target a population where protection from BCG vaccination<br />
is dubious or variable at best.<br />
Effects of BCG other than those directed<br />
against tuberculosis<br />
BCG has been shown to be protective against leprosy in some situations<br />
815-818,839 while not in others. 819 It has also shown to be effective against<br />
M. ulcerans, albeit with an apparently very short-lived protection. 840<br />
The best known indications <strong>for</strong> BCG against other than mycobacterial<br />
diseases are its use as an immunotherapeutic agent in the treatment of superficial<br />
bladder cancer 841-850 <strong>and</strong>, to a lesser extent, malignant melanoma. 851<br />
It has also been suggested that BCG reduces the risk of atopy <strong>and</strong> asthma,<br />
852-854 <strong>and</strong> reductions in the risk of intestinal nematodes in children 855 <strong>and</strong><br />
HIV-infected patients have been reported. 856,857<br />
Indications <strong>and</strong> recommendations <strong>for</strong> the use<br />
of BCG vaccination<br />
Approximately 100 million children now receive BCG every year. 723 The<br />
number of doses produced in the year 2000, in descending order, were the<br />
Copenhagen 1331 strain, D2PB302, Tokyo 172, Sofia SL 222, Pasteur 1173,<br />
Glaxo 1077, <strong>and</strong> the Russian strain. 723<br />
While there have been wide variations in the protection af<strong>for</strong>ded by<br />
BCG vaccination in different trials, the evidence is overwhelming that BCG<br />
provides protection against tuberculosis, especially against tuberculous meningitis<br />
<strong>and</strong> death from disseminated tuberculosis in children. Where it worked,<br />
its protective effect waned over time, to disappear after 15 to 20 years.<br />
The evidence <strong>for</strong> protection against bacteriologically confirmed tuberculosis<br />
in adults has been less consistent.<br />
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