[Retrospective evaluation of the effectiveness of the BCG vaccine campaign in newborns of Barcelona].

BACKGROUND

The aim of this study was to know the efficacy of the BCG vaccination campaign of the newborns of Barcelona carried out during the period from 1966-1974.

METHODS

To achieve this aim an epidemiologic investigation was undertaken by an observational analytical study of paired cases and controls. Two hundred and fifty randomly selected cases were studied between 1978-1988 from between 4-21 years of age during the study period. The cases were paired with 750 controls (1:3) with identical conditions and age, sex and place of residence. Statistical analysis of data was performed by the specific methods for this type of study.

RESULTS

The estimated gross odds ratio was 0.68; the interval of confidence 95% and 0.51-0.91 (p < 0.025). The efficacy of this vaccination campaign was estimated as weak at 32%, in the age group and investigation time being greater in males and diminished with time. The percentage of new cases of tuberculosis potentially prevented by this campaign was calculated at 13%.

CONCLUSIONS

The weak efficacy of the BCG vaccination campaign may be attributed not only to the unforeseen effects of this vaccine but also to the deficient operative aspects of the campaign itself.