title: [Epidemiology of nasopharyngeal carriage of Streptococcus pneumoniae in children < 6 years old in Seville].
abstract: BACKGROUND
  The aim of this investigation was to study the epidemiology of nasopharyngeal (NP) colonization with Streptococcus pneumoniae after the introduction of the heptavalent pneumococcal conjugate vaccine (PCV7).
  
  
  METHODS
  NP swabs were obtained from 848 children aged 6 months to six years seen in four primary care centres (healthy children) and in two emergency depeartments (sick children) from Seville. The study was conducted between February 2005 and June 2008.
  
  
  RESULTS
  A total of 278 (33%) children carried S. pneumoniae. Pneumococcal colonization was independently predicted by school attendance or child care participation (OR 2.21; 95% CI 1.54- 3.15; P=.0001) and younger age. Recent antibiotic use was protective (OR 0.68; 95% CI 0.48-0.94; P=.02). PCV7 uptake was 41%. Risk of carriage of PCV7- type pneumococci was lower among children who had received ≥1 dose of PCV7 (7% vs 29%; [OR 0.21; 95% CI 0.09-0.49; P=.0001]). The proportion of pneumococcal isolates with oral penicillin non-susceptibility and amoxicillin resistance were 33% and 3%, respectively. Amoxicillin resistance in colonized children was associated with prior antibiotic usage (OR 4.29; 95% CI 1.09-20.02).
  
  
  CONCLUSIONS
  NP colonization rates with PCV7- type pneumococci were low compared to those found in studies prior to PCV7 introduction, both in vaccinated and unvaccinated subjects. Factors related to age and overcrowding increased the prevalence of pneumococcal carriage. Use of antibiotics reduced the overall carriage of pneumococci, but was a risk factor for colonization with amoxicillin resistant pneumococci.
authors.affiliation: Sección de Infecciosos e Inmunodeficiencias, Hospital Infantil Universitario Virgen del Rocío, Sevilla, España. IOSANTAELLA@telefonica.net
authors.forename: Ignacio
authors.initials: I
authors.lastname: Obando
authors.forename: David
authors.initials: D
authors.lastname: Sánchez-Tatay
authors.forename: Agueda
authors.initials: A
authors.lastname: Molinos-Quintana
authors.forename: Isabel
authors.initials: I
authors.lastname: Delgado-Pecellin
authors.forename: Ana
authors.initials: A
authors.lastname: Porras
authors.forename: Beatriz
authors.initials: B
authors.lastname: Morillo-Gutiérrez
authors.forename: Asunción
authors.initials: A
authors.lastname: Fenoll
authors.forename: María José
authors.initials: MJ
authors.lastname: Lirola
mesh_terms: D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D004781:Environmental Exposure; D005191:Family Characteristics; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D022242:Pneumococcal Vaccines; D012703:Serotyping; D013030:Spain / Q000453:epidemiology; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification*; D014028:Tobacco Smoke Pollution; D014505:Urban Population; D014611:Vaccination / Q000706:statistics & numerical data
chemical_list: D022242:Pneumococcal Vaccines; D014028:Tobacco Smoke Pollution