title: Colonisation by Streptococcus pneumoniae and Staphylococcus aureus in healthy children.
abstract: A trial with a 7-valent pneumococcal-conjugate vaccine in children with recurrent acute otitis media showed a shift in pneumococcal colonisation towards non-vaccine serotypes and an increase in Staphylococcus aureus-related acute otitis media after vaccination. We investigated prevalence and determinants of nasopharyngeal carriage of Streptococcus pneumoniae and S aureus in 3198 healthy children aged 1-19 years. Nasopharyngeal carriage of S pneumoniae was detected in 598 (19%) children, and was affected by age (peak incidence at 3 years) and day-care attendance (odds ratio [OR] 2.14, 95% CI 1.44-3.18). S aureus carriage was affected by age (peak incidence at 10 years) and male sex (OR 1.46, 1.25-1.70). Serotyping showed 42% vaccine type pneumococci. We noted a negative correlation for co-colonisation of S aureus and vaccine-type pneumococci (OR 0.68, 0.48-0.94), but not for S aureus and non-vaccine serotypes. These findings suggest a natural competition between colonisation with vaccine-type pneumococci and S aureus, which might explain the increase in S aureus-related otitis media after vaccination.
authors.affiliation: Department of Paediatrics, Erasmus University Rotterdam, Rotterdam, Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Bogaert
authors.forename: A
authors.initials: A
authors.lastname: van Belkum
authors.forename: M
authors.initials: M
authors.lastname: Sluijter
authors.forename: A
authors.initials: A
authors.lastname: Luijendijk
authors.forename: R
authors.initials: R
authors.lastname: de Groot
authors.forename: H C
authors.initials: HC
authors.lastname: Rümke
authors.forename: H A
authors.initials: HA
authors.lastname: Verbrugh
authors.forename: P W M
authors.initials: PW
authors.lastname: Hermans
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D002353:Carrier State / Q000382:microbiology; D002648:Child; D002656:Child Day Care Centers; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000382:microbiology; D022242:Pneumococcal Vaccines; D012008:Recurrence; D012016:Reference Values; D012703:Serotyping; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D013296:Streptococcus pneumoniae / Q000145:classification / Q000302:isolation & purification*
chemical_list: D022242:Pneumococcal Vaccines