Effects of pneumococcal conjugate vaccine 2 years after its introduction, the Netherlands

Emerg Infect Dis. 2010 May;16(5):816-23. doi: 10.3201/eid1605.091223.

Abstract

In the Netherlands, the 7-valent pneumococcal conjugate vaccine (PCV-7) was implemented in a 3+1-dose schedule in the national immunization program for infants born after April 1, 2006. To assess the vaccine's effectiveness, we compared disease incidence before and after vaccine implementation (June 2004-June 2006 and June 2006-June 2008, respectively). We serotyped 2,552 invasive pneumococcal isolates from throughout the Netherlands, covering 25% of the country's population. Clinical characteristics were extracted from hospital records. After June 2006, vaccine-serotype invasive pneumococcal disease (IPD) decreased 90% (95% confidence interval [CI] 68%-97%) in children age eligible for PCV-7; simultaneously, however, non-vaccine-serotype IPD increased by 71% (not significant), resulting in a 44% total net IPD reduction (95% CI 7%-66%). IPD rates did not change for other age groups. In the Netherlands, PCV-7 offered high protection against vaccine-serotype IPD in vaccinated children, but increases of non-vaccine-serotype IPD reduced net vaccine benefits.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Child
  • Child, Preschool
  • Heptavalent Pneumococcal Conjugate Vaccine
  • Humans
  • Incidence
  • Infant
  • Middle Aged
  • Netherlands / epidemiology
  • Pneumococcal Infections / epidemiology*
  • Pneumococcal Infections / etiology
  • Pneumococcal Infections / physiopathology
  • Pneumococcal Infections / prevention & control*
  • Pneumococcal Vaccines / therapeutic use*
  • Population Surveillance
  • Serotyping
  • Streptococcus pneumoniae / immunology
  • Streptococcus pneumoniae / isolation & purification
  • Time Factors
  • Treatment Outcome

Substances

  • Heptavalent Pneumococcal Conjugate Vaccine
  • Pneumococcal Vaccines