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Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction
04:25

Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction

Published on: February 24, 2014

Serotypes responsible for invasive Streptococcus pneumoniae infections among children in Connecticut

E D Shapiro1, R Austrian

  • 1Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520-8064.

The Journal of Infectious Diseases
|January 1, 1994
PubMed

Insights

Active surveillance identified key Streptococcus pneumoniae serotypes causing invasive infections in Connecticut children. Seven serotypes were responsible for 84% of infections, informing future vaccine development.

Area of Science:

  • Pediatric Infectious Diseases
  • Microbiology
  • Epidemiology

Background:

  • Streptococcus pneumoniae causes invasive infections in children.
  • Understanding prevalent serotypes is crucial for effective prevention strategies.
  • Active surveillance provides real-time data on infection patterns.

Purpose of the Study:

  • To identify the predominant serotypes of Streptococcus pneumoniae causing invasive infections in children in Connecticut.
  • To inform the development of targeted pneumococcal vaccines for pediatric populations.

Main Methods:

  • Prospective surveillance from July 1984 to March 1993.
  • Collection and serotyping (Quellung reaction) of Streptococcus pneumoniae isolates from normally sterile sites.
  • Analysis of isolates from 722 children, with a focus on those under 2 years old.

Main Results:

  • Serotype 14 was the most frequent cause, accounting for 29% of infections.
  • Seven specific serotypes (4, 6B, 9V, 14, 18C, 19F, 23F) caused 84% of all invasive infections.
  • These seven serotypes were responsible for 86% of infections in children younger than 2 years.

Conclusions:

  • The identified seven serotypes are critical targets for pneumococcal conjugate vaccines in the United States.
  • Vaccine formulations should prioritize these highly prevalent serotypes to maximize protection in young children.
  • Continued surveillance is essential to monitor evolving serotype distribution.

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