Relationship between serotypes, age, and clinical presentation of invasive pneumococcal disease in Madrid, Spain, after introduction of the 7-valent pneumococcal conjugate vaccine into the vaccination calendar

Clin Vaccine Immunol. 2011 Jan;18(1):89-94. doi: 10.1128/CVI.00317-10. Epub 2010 Nov 3.

Abstract

To assess invasive pneumococcal disease (IPD) clinical presentations and relationships with age and serotype in hospitalized children (<15 years) after PCV7 implementation in Madrid, Spain, a prospective 2-year (May 2007 to April 2009) laboratory-confirmed (culture and/or PCR) IPD surveillance study was performed (22 hospitals). All isolates (for serotyping) and culture-negative pleural/cerebrospinal fluids were sent to the reference laboratory for pneumolysin (ply) and autolysin (lyt) gene PCR analysis. A total of 330 IPDs were identified: 263 (79.7%) confirmed by culture and 67 (20.3%) confirmed by PCR. IPD distribution by age (months) was as follows: 23.6% (<12), 15.8% (12 to 23), 15.5% (24 to 35), 22.4% (36 to 59), and 22.7% (>59). Distribution by clinical presentation was as follows: 34.5% bacteremic pneumonia, 30.3% pediatric parapneumonic empyema (PPE), 13.6% meningitis, 13.3% primary bacteremia, and 8.2% others. Meningitis and primary bacteremia were the most frequent IPDs in children <12 months old, and bacteremic pneumonia and PPE were most frequent in those >36 months old. Frequencies of IPD-associated serotypes were as follows: 1, 26.1%; 19A, 18.8%; 5, 15.5%; 7F, 8.5%; 3, 3.9%; nontypeable/other 30 serotypes, 27.3%. Serotype 1 was linked to respiratory-associated IPD (38.6% in bacteremic pneumonia and 38.0% in PPE) and children of >36 months (51.4% for 36 to 59 months and 40.0% for >59 months), while serotype 19A was linked to nonrespiratory IPDs (31.1% in meningitis, 27.3% in primary bacteremia, and 51.9% in others) and children of <24 months (35.9% for children of <12 months and 36.5% for those 12 to 23 months old), with high nonsusceptibility rates for penicillin, cefotaxime, and erythromycin. After PCV7 implementation, non-PCV7 serotypes caused 95.5% of IPDs. The new 13-valent conjugate vaccine would provide 79.1% coverage of serotypes responsible for IPDs in this series.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Distribution
  • Bacterial Proteins / genetics
  • Child
  • Child, Preschool
  • Culture Media
  • Female
  • Heptavalent Pneumococcal Conjugate Vaccine
  • Humans
  • Immunization Schedule
  • Infant
  • Male
  • N-Acetylmuramoyl-L-alanine Amidase / genetics
  • Pneumococcal Infections / epidemiology*
  • Pneumococcal Infections / microbiology
  • Pneumococcal Infections / physiopathology*
  • Pneumococcal Infections / prevention & control
  • Pneumococcal Vaccines / administration & dosage*
  • Pneumococcal Vaccines / immunology
  • Polymerase Chain Reaction
  • Population Surveillance / methods
  • Serotyping
  • Spain / epidemiology
  • Streptococcus pneumoniae / classification*
  • Streptococcus pneumoniae / genetics
  • Streptococcus pneumoniae / immunology
  • Streptococcus pneumoniae / isolation & purification
  • Streptolysins / genetics
  • Vaccination

Substances

  • Bacterial Proteins
  • Culture Media
  • Heptavalent Pneumococcal Conjugate Vaccine
  • Pneumococcal Vaccines
  • Streptolysins
  • plY protein, Streptococcus pneumoniae
  • N-Acetylmuramoyl-L-alanine Amidase