title: Carriage of Streptococcus pneumoniae 3 years after start of vaccination program, the Netherlands.
abstract: To evaluate the effectiveness of the 7-valent pneumococcal conjugate vaccine (PCV7) program, we conducted a cross-sectional observational study on nasopharyngeal carriage of Streptococcus pneumoniae 3 years after implementation of the program in the Netherlands. We compared pneumococcal serotypes in 329 prebooster 11-month-old children, 330 fully vaccinated 24-month-old children, and 324 parents with age-matched pre-PCV7 (unvaccinated) controls (ages 12 and 24 months, n = 319 and n = 321, respectively) and 296 of their parents. PCV7 serotype prevalences before and after PCV7 implementation, respectively, were 38% and 8% among 11-month-old children, 36% and 4% among 24-month-old children, and 8% and 1% among parents. Non-PCV7 serotype prevalences were 29% and 39% among 11-month-old children, 30% and 45% among 24-month-old children, and 8% and 15% among parents, respectively; serotypes 11A and 19A were most frequently isolated. PCV7 serotypes were largely replaced by non-PCV7 serotypes. Disappearance of PCV7 serotypes in parents suggests strong transmission reduction through vaccination.
authors.affiliation: University Medical Center, Utrecht, the Netherlands.
authors.forename: Judith
authors.initials: J
authors.lastname: Spijkerman
authors.forename: Elske J M
authors.initials: EJ
authors.lastname: van Gils
authors.forename: Reinier H
authors.initials: RH
authors.lastname: Veenhoven
authors.forename: Eelko
authors.initials: E
authors.lastname: Hak
authors.forename: Ed P F
authors.initials: EP
authors.lastname: Yzerman
authors.forename: Arie
authors.initials: A
authors.lastname: van der Ende
authors.forename: Alienke J
authors.initials: AJ
authors.lastname: Wijmenga-Monsuur
authors.forename: Germie P J M
authors.initials: GP
authors.lastname: van den Dobbelsteen
authors.forename: Elisabeth A M
authors.initials: EA
authors.lastname: Sanders
mesh_terms: D000328:Adult; D002353:Carrier State / Q000382:microbiology*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D009426:Netherlands / Q000453:epidemiology; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000592:standards*; D015995:Prevalence; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000235:genetics / Q000502:physiology*; D014611:Vaccination
chemical_list: D022242:Pneumococcal Vaccines