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Updated: Aug 15, 2026

Non-Invasive Model of Neuropathogenic Escherichia coli Infection in the Neonatal Rat
Published on: October 29, 2014
Fifteen years of experience with bacterial meningitis
K G Dawson1, J C Emerson, J L Burns
1Department of Pediatrics, University of Washington, Children's Hospital and Regional Medical Center, Seattle 98105, USA.
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.
Insights
Haemophilus influenzae type b (Hib) vaccine introduction significantly reduced Hib meningitis in children. Other bacterial meningitis pathogens like Streptococcus pneumoniae and Neisseria meningitidis remained steady.
Area of Science:
- Pediatrics
- Infectious Diseases
- Epidemiology
Background:
- Haemophilus influenzae type b (Hib) vaccines have significantly changed childhood bacterial meningitis epidemiology.
- This study aimed to document these epidemiological shifts within a pediatric teaching hospital setting.
Purpose of the Study:
- To describe the changes in bacterial meningitis patterns in children.
- To analyze the impact of Haemophilus influenzae type b (Hib) vaccine introduction on meningitis epidemiology.
Main Methods:
- Retrospective review of patient charts at Children's Hospital and Regional Medical Center, Seattle.
- Analysis of bacterial meningitis cases from 1981 to 1995, divided into three 5-year periods based on Hib vaccine availability (unconjugated, transitional, conjugate).
Main Results:
- A total of 806 bacterial meningitis cases were identified.
- Haemophilus influenzae was the predominant pathogen before conjugate vaccine availability (73% and 69% in the first two periods).
- Following conjugate vaccine introduction, Haemophilus influenzae cases dramatically declined to 16%, while Streptococcus pneumoniae and Neisseria meningitidis remained consistent.
Conclusions:
- The study observed a significant shift in childhood meningitis etiology post-Hib vaccine introduction.
- While Haemophilus influenzae meningitis decreased, the incidence of Streptococcus pneumoniae and Neisseria meningitidis meningitis remained stable.
Related Concept Videos
Bacterial Meningitis
Viral Meningitis
Cryptococcal Meningitis
Bacterial Meningitis I: Introduction
Bacterial Meningitis II: Pathophysiology
Brain Abscess l: Introduction

