title: A case-control study of protection against tuberculosis by BCG revaccination in Recife, Brazil.
abstract: METHODS
  Metropolitan region of Recife, Brazil.
  
  
  OBJECTIVE
  To estimate the additional protection against tuberculosis (TB) provided by a second dose of bacille Calmette-Guérin (BCG) vaccine.
  
  
  METHODS
  Case-control study. Cases were cases of TB newly diagnosed by the TB control programme, independent of clinical form. Three matched neighbourhood controls were selected using a systematic routine, starting from the case's address. The matching was within the age groups 7-9, 10-14 and 15-19 years.
  
  
  RESULTS
  Analysis was conducted among 169 cases and 477 controls. For the efficacy of BCG revaccination against TB overall, matched (crude) vaccine effectiveness (VE) was -3 (95% CI -50-29) and matched (adjusted) VE was 8 (95% CI -77-52).
  
  
  CONCLUSIONS
  This study suggests that a second dose of BCG does not offer additional protection. Revaccination should not be offered. As large numbers of subjects are already vaccinated and vaccine appears to offer some protection in older subjects, further studies with larger sample sizes could investigate the potential efficacy of revaccination with BCG in the age group > or = 15 years.
authors.affiliation: Department of Mother and Child Health, Federal University of Pernambuco, Recife, Brazil. odimariles@globo.com
authors.forename: O M S
authors.initials: OM
authors.lastname: Dantas
authors.forename: R A de A
authors.initials: RA
authors.lastname: Ximenes
authors.forename: M de F P M
authors.initials: Mde F
authors.lastname: de Albuquerque
authors.forename: N L C L
authors.initials: NL
authors.lastname: da Silva
authors.forename: U R
authors.initials: UR
authors.lastname: Montarroyos
authors.forename: W V
authors.initials: WV
authors.lastname: de Souza
authors.forename: T C C
authors.initials: TC
authors.lastname: Pereira
authors.forename: A R L
authors.initials: AR
authors.lastname: Campelo
authors.forename: L C
authors.initials: LC
authors.lastname: Rodrigues
mesh_terms: D000293:Adolescent; D000328:Adult; D001500:BCG Vaccine / Q000008:administration & dosage*; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D012959:Socioeconomic Factors; D014376:Tuberculosis / Q000453:epidemiology / Q000517:prevention & control*; D014505:Urban Population
chemical_list: D001500:BCG Vaccine