Duration of BCG protection against tuberculosis and change in effectiveness with time since vaccination in Norway: a retrospective population-based cohort study.

BACKGROUND Little is known about how long the BCG vaccine protects against tuberculosis. We assessed the long-term vaccine effectiveness (VE) in Norwegian-born individuals. METHODS In this retrospective population-based cohort study, we studied Norwegian-born individuals aged 12-50 years who were tuberculin skin test (TST) negative and eligible for BCG… (More)