title: Effectiveness of Haemophilus influenzae type b vaccination against bacterial pneumonia in Colombia.
abstract: OBJECTIVE
  To assess the effectiveness of a Hib vaccination program against X-ray defined bacterial pneumonia in children <2 years in Colombia.
  
  
  METHODS
  389 cases of radiologically confirmed pneumonia were recruited from hospitals in Bogota and Medellin, Colombia. Two controls per case, matched on age, sex, and socio-economic level, were selected from children attending child health services at the hospitals where pneumonia cases were admitted.
  
  
  RESULTS
  The risk of having X-ray confirmed pneumonia decreased with each Hib dose received; the vaccine effectiveness was 47% (2-72%) among those receiving one dose; 52% for two doses received, and 55% for three doses. These effectiveness levels remained after adjusting for other factors associated with risk of pneumonia.
  
  
  CONCLUSIONS
  This study indicates that trials may have underestimated the proportion of radiological pneumonia in the under 2s that is due to Hib. This suggests that the impact of the vaccination will be greater than expected if it can be extended to reach the poorest children, who are at the greatest risk.
authors.affiliation: Instituto Nacional de Salud de Colombia, Universidad Nacional de Colombia, Carrera 68D # 40A-50, apto 102 int 5, Bogota, Colombia. fdelahoz@007mundo.com
authors.forename: Fernando
authors.initials: F
authors.lastname: de la Hoz
authors.forename: Ana Betty
authors.initials: AB
authors.lastname: Higuera
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Di Fabio
authors.forename: Mauricio
authors.initials: M
authors.lastname: Luna
authors.forename: Alberto Gómez
authors.initials: AG
authors.lastname: Naranjo
authors.forename: María
authors.initials: M
authors.lastname: de la Luz Valencia
authors.forename: Desiree
authors.initials: D
authors.lastname: Pastor
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Hall
mesh_terms: D016022:Case-Control Studies; D003105:Colombia / Q000453:epidemiology; D006192:Haemophilus Infections / Q000453:epidemiology / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000008:administration & dosage*; D019741:Haemophilus influenzae type b / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018410:Pneumonia, Bacterial / Q000453:epidemiology / Q000517:prevention & control*
chemical_list: D018073:Haemophilus Vaccines