title: Fifteen years of experience with bacterial meningitis.
abstract: BACKGROUND
  Introduction of Haemophilus influenzae type b (Hib) vaccines has dramatically altered the epidemiology of bacterial meningitis in children. The goal of this study was to describe these changes in a pediatric teaching hospital.
  
  
  METHODS
  Patient charts at Children's Hospital and Regional Medical Center, Seattle, were identified by diagnosis codes and reviewed retrospectively. The 1981 to 1995 time period was chosen to incorporate three distinct 5-year periods: before the use of unconjugated Hib vaccine; between the unconjugated and conjugate vaccines; and after the conjugate vaccines were available for routine immunization of infants.
  
  
  RESULTS
  Bacterial meningitis was identified in 806 cases. In 13 premature infant cases Escherichia coli was most frequently isolated (6 cases). Group B Streptococcus, E. coli and Listeria monocytogenes were the most common pathogens in 87 neonatal cases. The most common pathogens in 706 cases of childhood meningitis were H. influenzae, Streptococcus pneumoniae and Neisseria meningitidis. H. influenzae was the most common pathogen in the first two time periods (73 and 69% of childhood cases, respectively), but not so in the third period (16%).
  
  
  CONCLUSIONS
  A changing pattern in childhood meningitis was observed during the study period. H. influenzae cases dramatically declined, altering the relative proportions of other pathogens, S. pneumoniae and N. meningitidis. However, the number of cases caused by these latter pathogens remained steady.
authors.affiliation: Department of Pediatrics, University of Washington, Children's Hospital and Regional Medical Center, Seattle 98105, USA.
authors.forename: K G
authors.initials: KG
authors.lastname: Dawson
authors.forename: J C
authors.initials: JC
authors.lastname: Emerson
authors.forename: J L
authors.initials: JL
authors.lastname: Burns
mesh_terms: D000293:Adolescent; D002555:Cerebrospinal Fluid / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D006192:Haemophilus Infections / Q000175:diagnosis / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D019741:Haemophilus influenzae type b / Q000276:immunology; D006776:Hospitals, Pediatric; D006784:Hospitals, Teaching; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016920:Meningitis, Bacterial / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D008585:Meningitis, Meningococcal / Q000175:diagnosis; D009345:Neisseria meningitidis / Q000302:isolation & purification; D011008:Pneumococcal Infections / Q000175:diagnosis; D012189:Retrospective Studies; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D014611:Vaccination / Q000706:statistics & numerical data*; D014861:Washington / Q000453:epidemiology
chemical_list: D018073:Haemophilus Vaccines