title: Revaccination with Bacillus Calmette-Guerin (BCG) vaccine does not reduce morbidity from malaria in African children.
abstract: BACKGROUND
  Studies in West Africa and elsewhere have suggested that Bacillus Calmette-Guérin (BCG) vaccine given at birth is beneficial for child survival. It is possible that this effect is mediated partly through an effect on malaria, a hypothesis supported by animal studies. We investigated whether revaccination with BCG at 19 months of age reduced morbidity from malaria.
  
  
  METHODS
  In the capital of Guinea-Bissau, between January and November 2003, children who had previously received BCG vaccination and who did not have a strong reaction to tuberculin were individually randomised to either receive revaccination with BCG at the age of 19 months or to be a control. Episodes of malaria were recorded during the 2003 malaria transmission season through passive case detection at health centres in the study area and at the national hospital. Cross-sectional surveys were carried out at the beginning and at the end of the rainy season.
  
  
  RESULTS
  Incidence rates of first episodes of malaria associated with any level of parasitaemia were 0.16 episodes per child-year among 713 revaccinated children and 0.12 among 720 control children [incidence rate ratio (IRR) = 1.37; 95% confidence intervals (CI): 0.84-2.25]. Results were similar when the diagnosis of malaria was based on the presence of parasitaemia >5000 parasites/microl (IRR = 1.30; 95% CI: 0.61-2.77). The incidence of all-cause hospitalisation was higher among BCG-revaccinated children than among controls (IRR = 2.13; 95% CI: 1.10-4.13). There were no significant differences in the prevalence of parasitaemia between the two groups of children at cross-sectional surveys.
  
  
  CONCLUSIONS
  We found no evidence that BCG revaccination reduces morbidity from malaria.
authors.affiliation: Projecto de Saúde de Bandim, Guiné-Bissau, Bissau. a.rodrigues@bandim.org
authors.forename: Amabelia
authors.initials: A
authors.lastname: Rodrigues
authors.forename: Joanna Armstrong
authors.initials: JA
authors.lastname: Schellenberg
authors.forename: Adam
authors.initials: A
authors.lastname: Roth
authors.forename: Christine Stabell
authors.initials: CS
authors.lastname: Benn
authors.forename: Peter
authors.initials: P
authors.lastname: Aaby
authors.forename: Brian
authors.initials: B
authors.lastname: Greenwood
mesh_terms: D001500:BCG Vaccine / Q000008:administration & dosage*; D003430:Cross-Sectional Studies; D005260:Female; D006169:Guinea-Bissau / Q000453:epidemiology; D006760:Hospitalization; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary / Q000379:methods*; D015994:Incidence; D007223:Infant; D008288:Malaria / Q000097:blood / Q000453:epidemiology / Q000517:prevention & control*; D008297:Male; D009017:Morbidity; D018512:Parasitemia / Q000453:epidemiology / Q000517:prevention & control; D015995:Prevalence; D017678:Sex Distribution; D016896:Treatment Outcome; D014373:Tuberculin / Q000276:immunology
chemical_list: D001500:BCG Vaccine; D014373:Tuberculin