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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 of Streptococcus pneumoniae isolated from blood cultures at Boston City Hospital between 1979 and 1982

M A Barry, D E Craven, M Finland

    The Journal of Infectious Diseases
    |March 1, 1984
    PubMed

    Insights

    Pneumococcal bacteremia serotypes were analyzed in children and adults. Most pediatric and adult cases involved serotypes covered by the 14-valent pneumococcal vaccine, indicating its broad effectiveness.

    Area of Science:

    • Medical Microbiology
    • Infectious Diseases
    • Vaccinology

    Background:

    • Pneumococcal bacteremia remains a significant cause of morbidity and mortality.
    • Understanding the prevalent serotypes is crucial for vaccine development and public health strategies.

    Purpose of the Study:

    • To identify and compare the serotypes of Streptococcus pneumoniae causing bacteremia in pediatric and adult populations.
    • To assess the coverage of the 14-valent pneumococcal vaccine against isolated serotypes.

    Main Methods:

    • Retrospective analysis of 271 pneumococcal isolates from blood cultures between January 1979 and December 1982.
    • Categorization of isolates by patient age (pediatric vs. adult).
    • Comparison of isolated serotypes with those included in the 14-valent pneumococcal vaccine.

    Main Results:

    • Streptococcus pneumoniae isolates were evenly distributed between children (48%) and adults (52%).
    • Common pediatric serotypes (14, 19, 18, 6, 4, 9) accounted for 90% of pediatric isolates.
    • Common adult serotypes (12, 9, 8, 4, 3, 6) comprised 55.3% of adult isolates.
    • The 14-valent vaccine covered >96% of pediatric isolates and 72.7% of adult isolates.

    Conclusions:

    • The majority of pneumococcal bacteremia cases are caused by serotypes included in the 14-valent pneumococcal vaccine.
    • While vaccine coverage is high for pediatric isolates, it is lower for adult isolates.
    • Minor shifts in prevalent pneumococcal serotypes causing bacteremia have been observed over the decade.

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