title: [Epidemiological study of nasopharyngeal carriers of Streptococcus pneumoniae in children in Murcia region].
abstract: OBJECTIVE
  Streptococcus pneumoniae is a human pathogen that requires prior nasopharyngeal colonization to cause disease. An epidemiological study was conducted on nasopharyngeal carriers of pneumococci in healthy children in Murcia after the introduction of the VCN7, and immediately before the marketing of new vaccines, with the aim of determining the influence of vaccination in our geographic area, and other factors in relation to the state of being a carrier, and the different circulating serotypes.
  
  
  METHODS
  A multicentre study was conducted in in 60 primary care health centres in summer 2009 and winter of 2010. A nasopharyngeal swab was collected, and an epidemiological study was carried out on 1562 children aged 1 and 4 years. Of the 1562 nasopharyngeal samples, pneumococci were found in 489 of them, with 343 of them able to be serotyped (70.2%).
  
  
  RESULTS
  The prevalence of carriers was 31.3%. Of the patients included, 61.7% (964/1562) had received at least one dose of VCN7. Only 12.8% of the identified serotypes were vaccine serotypes. The independent protective factors against colonization were; Summer time in all age groups, previous vaccination in all the children (OR: 0.75; 95%CI: 0.56-0.93]; P=.01, and in 1-year-olds (OR: 0.6; 95%CI: 0.42-0.84; P=.002), and had taken antibiotics in the last month in the total cohort [OR: 0.69; 95%CI: 0.50-0.96). On the other hand, attendance at school or day-care centre (OR: 1.85; 95%CI: 1.27-2.18; P=.001), number of siblings (OR: 1.3; 95%CI: 1.01-1.91), and passive tobacco smoke exposure (OR: 1.33; 95%CI: 1.02-1.73), were colonization risk factors. The serotypes 6A, 19A, 23B, 15A/B, 11A, 14, 23A/F, 3 y 19F were the most prevalent.
  
  
  CONCLUSIONS
  A low proportion of SV was found, with 14, 23F and 19F are persisting. A high prevalence of serotypes 6A and 19A was found. Summer time, vaccination, and the prior administration of antibiotics proved to be protective against colonization, whereas schooling, smoking, and siblings contributed to it.
authors.affiliation: Servicio de Pediatría, Hospital Infantil Universitario Virgen de la Arrixaca, Murcia, España. Electronic address: santiagoalfayatem@gmail.com.
authors.forename: Santiago
authors.initials: S
authors.lastname: Alfayate-Miguélez
authors.affiliation: Servicio de Microbiología, Hospital Universitario Virgen de la Arrixaca, Murcia, España.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Ruiz-Gómez
authors.affiliation: Laboratorio de Referencia de Neumococos - Instituto de Salud Carlos III, Majadahonda, Madrid, España.
authors.forename: Asunción
authors.initials: A
authors.lastname: Fenoll-Comes
authors.affiliation: Servicio de Pediatría, Hospital Infantil Universitario Virgen de la Arrixaca, Murcia, España.
authors.forename: Manuel
authors.initials: M
authors.lastname: Sanchez-Solis-de Querol
authors.affiliation: Área del Hospital Morales Meseguer, Centro de Salud El Ranero, Murcia, España.
authors.forename: Antonio
authors.initials: A
authors.lastname: Iofrío-de Arce
authors.affiliation: Área del Hospital Virgen de la Arrixaca, Centro de Salud de Algezares, Murcia, España.
authors.forename: Angela
authors.initials: A
authors.lastname: Casquet-Barceló
authors.affiliation: Área del Hospital Reina Sofía, Centro de Salud de Vistabella, Murcia, España.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Sanz-Mateo
authors.affiliation: Área del Hospital Santa Lucía, Centro de Salud Barrio del Peral, Cartagena, Murcia, España.
authors.forename: Pilar
authors.initials: P
authors.lastname: Espejo-García
authors.affiliation: Área del Hospital Rafael Méndez, Centro de Salud de Totana, Totana, Murcia, España.
authors.forename: Sebastián
authors.initials: S
authors.lastname: Lorente-García
authors.affiliation: Área del Hospital del Mar Menor, Centro de Salud de San Pedro del Pinatar, San Pedro del Pinatar, Murcia, España.
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Sánchez-Andrada
authors.affiliation: Área del Hospital de Yecla, Centro de Salud Mariano Yago, Yecla, Murcia, España.
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Vigueras-Abellán
mesh_terms: D002353:Carrier State / Q000453:epidemiology*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000517:prevention & control; D012703:Serotyping; D013030:Spain / Q000453:epidemiology; D022541:Streptococcal Vaccines; D013296:Streptococcus pneumoniae / Q000145:classification / Q000302:isolation & purification*
chemical_list: D022541:Streptococcal Vaccines
keywords: Colonización nasofaríngea; Conjugate vaccines; Factores de riesgo; Nasopharyngeal colonization; Risk factors; Streptococcus pneumoniae; Vacunas conjugadas