title: The impact of a change in bacille Calmette-Guérin vaccine policy on tuberculosis incidence in children in Cape Town, South Africa.
abstract: BACKGROUND
  A decision by the South African National Department of Health to change the route of administration and strain of bacille Calmette-Guérin (BCG) vaccine was implemented in Cape Town, South Africa, between July and December 2000. This provided an opportunity to compare the incidence of tuberculosis and proportion with disseminated disease in children less than 2 years old before and after the changeover from percutaneous (PC) Tokyo 172 BCG to intradermal (ID) 1331 Danish BCG immunization.
  
  
  METHODS
  Clinical records of all tuberculosis patients aged less than 2 years at diagnosis and born between January 1, 1999, and June 30, 2000 (PC cohort) and between January 1, 2001, and June 30, 2002 (ID cohort) were collected. All cases were reviewed for likelihood of TB, its severity and disease dissemination.
  
  
  RESULTS
  The number of reported patients with tuberculosis in the PC cohort was 1369 and in the ID cohort 1397, giving incidence rates of 866 (95% confidence interval [CI], 821-913) and 858 (95% CI, 814-904) per 100,000 person-years, respectively. The proportion who had disseminated disease (meningitis and/or miliary spread) was significantly lower in the ID cohort (4.7%) than in the PC cohort (8.6%) (relative risk, 0.54; 95% CI, 0.40-0.72). Those not vaccinated had a significantly higher proportion of disseminated disease cases (29.2%) than the PC and ID groups combined (6.6%) (relative risk, 4.4; 95% CI, 2.7-6.7).
  
  
  CONCLUSIONS
  A program using Danish 1331 BCG given intradermally did not prevent more tuberculosis cases in children overall as compared with a program using Tokyo 172 BCG given percutaneously but reduced the proportion with disseminated disease.
authors.affiliation: South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa. hassan@rmh.uct.ac.za
authors.forename: Hassan
authors.initials: H
authors.lastname: Mahomed
authors.forename: Maurice
authors.initials: M
authors.lastname: Kibel
authors.forename: Tony
authors.initials: T
authors.lastname: Hawkridge
authors.forename: H Simon
authors.initials: HS
authors.lastname: Schaaf
authors.forename: Willem A
authors.initials: WA
authors.lastname: Hanekom
authors.forename: Karen
authors.initials: K
authors.lastname: Iloni
authors.forename: Desiré
authors.initials: D
authors.lastname: Michaels
authors.forename: Lesley
authors.initials: L
authors.lastname: Workman
authors.forename: Suzanne
authors.initials: S
authors.lastname: Verver
authors.forename: Lawrence
authors.initials: L
authors.lastname: Geiter
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Hussey
mesh_terms: D015331:Cohort Studies; D006291:Health Policy; D006801:Humans; D017589:Immunization Programs; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D009163:Mycobacterium bovis / Q000276:immunology*; D013019:South Africa / Q000453:epidemiology; D014376:Tuberculosis / Q000453:epidemiology* / Q000276:immunology* / Q000473:pathology; D032581:Tuberculosis Vaccines / Q000276:immunology*; D014390:Tuberculosis, Meningeal / Q000453:epidemiology; D014391:Tuberculosis, Miliary / Q000453:epidemiology
chemical_list: D032581:Tuberculosis Vaccines