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Erythromycin-nonsusceptible Streptococcus pneumoniae in children, 1999-2001

M Catherine McEllistrem1, Jennifer M Adams, Kathleen Shutt

  • 1University of Pittsburgh Graduate School of Public Health and School of Medicine, Pittsburgh, Pennsylvania 15213-2582, USA. mcellistremc@msx.dept-med.pitt.edu

Emerging Infectious Diseases
|June 21, 2005
PubMed

Insights

Invasive Streptococcus pneumoniae infections in children decreased significantly after 1999. This decline in erythromycin-nonsusceptible strains was linked to the pneumococcal 7-valent conjugate vaccine.

Area of Science:

  • Pediatric infectious diseases
  • Bacteriology
  • Vaccinology

Background:

  • Invasive Streptococcus pneumoniae infections pose a significant public health threat, particularly in pediatric populations.
  • Erythromycin resistance in Streptococcus pneumoniae has been a growing concern, complicating treatment options.
  • The England14-9 clone carrying the mefE gene has been identified as a significant contributor to antibiotic resistance.

Purpose of the Study:

  • To analyze trends in invasive erythromycin-nonsusceptible Streptococcus pneumoniae infections in children in Baltimore, Maryland.
  • To investigate the potential impact of the pneumococcal 7-valent conjugate vaccine on these infection rates.
  • To identify specific bacterial clones associated with observed changes in antimicrobial susceptibility.

Main Methods:

  • Retrospective analysis of pediatric invasive Streptococcus pneumoniae isolates.
  • Surveillance data from Baltimore, Maryland, spanning 1995-2001.
  • Antimicrobial susceptibility testing and molecular typing of isolates.

Main Results:

  • Invasive erythromycin-nonsusceptible Streptococcus pneumoniae rates increased from 1995 to 1999.
  • A significant decrease of 53.6% in these infection rates was observed between 1999 and 2001.
  • The decline was partially attributed to a reduction in strains related to the mefE-carrying England14-9 clone.

Conclusions:

  • The widespread use of the pneumococcal 7-valent conjugate vaccine likely contributed to the observed decline in invasive erythromycin-nonsusceptible Streptococcus pneumoniae infections.
  • Continued surveillance is crucial to monitor antibiotic resistance trends and vaccine effectiveness in pediatric populations.

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