title: Nasopharyngeal carriage of Streptococcus pneumoniae in Romanian children before the introduction of the pneumococcal conjugated vaccination into the national immunization programme: a national, multi-centre, cross-sectional observational study.
abstract: OBJECTIVE
  We analysed the distribution of vaccine and non-vaccine Streptococcus pneumoniae serotypes and the antimicrobial susceptibility of pneumococcal strains isolated from healthy Romanian children.
  
  
  METHODS
  A multi-centre cross-sectional study was performed in four counties to evaluate carried strains of S. pneumoniae isolated from 2000 children aged 0-5 years.
  
  
  RESULTS
  S. pneumoniae carriage was detected in 25.25% of the tested children. Carriage increased from 16.7% among infants to 29.4% in 3-5-year-old children (p<0.0001). The proportions of the serotypes included in pneumococcal conjugate vaccines PCV7, PCV10, and PCV13 among our isolates were 39.9%, 40.1%, and 58.7%, respectively. Erythromycin resistance was 72.5%, and it was significantly lower in non-vaccine serotypes compared with PCV13 serotypes: 57.3% versus 83.6% (p<10(-7)). Penicillin minimum inhibitory concentrations (MICs) >0.064mg/l were recorded in 71.6%, but the penicillin MIC was >2mg/l for only 8.4% of tested isolates.
  
  
  CONCLUSIONS
  In Romanian children, the majority of carried S. pneumoniae isolates are vaccine serotypes. The isolates with MICs defining macrolide resistance were very frequent, as well as the isolates with MICs defining penicillin resistance in the case of meningitis or penicillin dose-dependent susceptibility for other infections, mainly for the strains belonging to PCV13 serotypes. The implementation of PCV13 within the Romanian national immunization programme could reduce the circulation of these strains with higher macrolide and/or penicillin MICs.
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania; University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania.
authors.forename: Monica
authors.initials: M
authors.lastname: Luminos
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania.
authors.forename: Olga
authors.initials: O
authors.lastname: Dorobat
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania; University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania.
authors.forename: George
authors.initials: G
authors.lastname: Jugulete
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania; University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania.
authors.forename: Gabriel Adrian
authors.initials: GA
authors.lastname: Popescu
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania.
authors.forename: Dragos
authors.initials: D
authors.lastname: Florea
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania.
authors.forename: Anca
authors.initials: A
authors.lastname: Draganescu
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania; University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania.
authors.forename: Anca Streinu
authors.initials: AS
authors.lastname: Cercel
authors.affiliation: National Institute for Infectious Diseases "Prof Dr Matei Bals", Grozovici 1, 021105 Bucharest, Romania; University of Medicine and Pharmacy "Carol Davila", Bucharest, Romania. Electronic address: arafila@yahoo.com.
authors.forename: Alexandru
authors.initials: A
authors.lastname: Rafila
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D024881:Drug Resistance, Bacterial; D004917:Erythromycin; D006801:Humans; D017589:Immunization Programs; D007223:Infant; D007231:Infant, Newborn; D018942:Macrolides / Q000494:pharmacology; D009305:Nasopharynx / Q000382:microbiology*; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology; D022242:Pneumococcal Vaccines; D012383:Romania; D065288:Serogroup; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification*; D014611:Vaccination; D018074:Vaccines, Conjugate
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides; D010406:Penicillins; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate; D004917:Erythromycin
keywords: Macrolide resistance; Penicillin MIC; Pneumococcal conjugated vaccine serotypes; Streptococcus pneumoniae carriage