Dataset Information

BCG revaccination does not protect against leprosy in the Brazilian Amazon: a cluster randomised trial.

ABSTRACT:

Background

Although BCG has been found to impart protection against leprosy in many populations, the utility of repeat or booster BCG vaccinations is still unclear. When a policy of giving a second BCG dose to school children in Brazil was introduced, a trial was conducted to assess its impact against tuberculosis, and a leprosy component was then undertaken in parallel.

Objective

to estimate the protection against leprosy imparted by a second dose of BCG given to schoolchildren.

Methods and findings

This is a cluster randomised community trial, with 6 years and 8 months of follow-up.

Study site

City of Manaus, Amazon region, a leprosy-endemic area in Brazil.

Participants

99,770 school children with neonatal BCG (aged 7-14 years at baseline), of whom 42,662 were in the intervention arm (revaccination).

Intervention

BCG given by intradermal injection.

Main outcome

Leprosy (all clinical forms).

Results

The incidence rate ratio of leprosy in the intervention over the control arm within the follow-up, in schoolchildren with neonatal BCG, controlled for potential confounders and adjusted for clustering, was 0.99 (95% confidence interval: 0.68 to 1.45).

Conclusions/significance

There was no evidence of protection conferred by the second dose of BCG vaccination in school children against leprosy during the trial follow-up. These results point to a need to consider the effectiveness of the current policy of BCG vaccination of contacts of leprosy cases in Brazilian Amazon region.

SUBMITTER: Cunha SS

PROVIDER: S-EPMC2238709 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

BCG revaccination does not protect against leprosy in the Brazilian Amazon: a cluster randomised trial.

Cunha Sérgio S SS Alexander Neal N Barreto Mauricio L ML Pereira Emilia S ES Dourado Inês I Maroja Maria de Fátima Mde F Ichihara Yury Y Brito Silvana S Pereira Susan S Rodrigues Laura C LC

PLoS neglected tropical diseases 20080213 2

<h4>Background</h4>Although BCG has been found to impart protection against leprosy in many populations, the utility of repeat or booster BCG vaccinations is still unclear. When a policy of giving a second BCG dose to school children in Brazil was introduced, a trial was conducted to assess its impact against tuberculosis, and a leprosy component was then undertaken in parallel.<h4>Objective</h4>to estimate the protection against leprosy imparted by a second dose of BCG given to schoolchildren.< ...[more]

PMID: 18270542

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Dataset Information

BCG revaccination does not protect against leprosy in the Brazilian Amazon: a cluster randomised trial.

Background

Objective

Methods and findings

Study site

Participants

Intervention

Main outcome

Results

Conclusions/significance

Publications

BCG revaccination does not protect against leprosy in the Brazilian Amazon: a cluster randomised trial.

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