title: Molecular epidemiology of serotype 19A Streptococcus pneumoniae isolated from children in Beijing, 1997-2006.
abstract: BACKGROUND
  Despite the prevalence of Streptococcus pneumoniae serotype 19A, the molecular characteristics of this serotype are yet to be fully elucidated. The aim of this study was therefore to determine the homology of the serotype 19A in China.
  
  
  METHODS
  Pulsed-field gel electrophoresis and multilocus sequence typing were done to these forty-nine serotype 19A isolates to investigate the relationship between the strains prevalent in Beijing and other regions.
  
  
  RESULTS
  From 1997 to 2006, the percentage of serotype 19A isolates increased. The susceptibility rate to penicillin and amoxicillin decreased and the resistance rate to cefuroxime increased. ST320 was the most prevalent ST, followed by ST3546. There were six new STs identified in our study. The serotype 19A strains were classified into six different pulsed-field gel electrophoresis (PFGE) patterns. ST320, which was associated with two different PFGE patterns (A and D), accounted for 32 isolates, and ST3546, which was associated with two PFGE patterns (B and E), accounted for eight isolates.
  
  
  CONCLUSIONS
  From 2003 onwards, ST320 was the most common ST and the rate of resistance to cefuroxime increased significantly. Further long-term surveys of Streptococcus pneumoniae serotype 19A are required to monitor ST prevalence and antimicrobial resistance in this important human pathogen.
authors: Key Laboratory of Major Diseases in Children and National Key Discipline of Pediatrics, Ministry of Education, Beijing Pediatric Research Institute, Beijing Children's Hospital Affiliated to Capital Medical University, Beijing 100045, China.
authors: Lian
authors: L
authors: Xue
authors: Kai-Hu
authors: KH
authors: Yao
authors: Sang-Jie
authors: SJ
authors: Yu
authors: Zun-Jie
authors: ZJ
authors: Liu
authors: Jing
authors: J
authors: Qian
authors: Xu-Zhuang
authors: XZ
authors: Shen
authors: Yong-Hong
authors: YH
authors: Yang
mesh_terms: D002675:Child, Preschool; D002681:China; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D017720:Molecular Epidemiology; D011008:Pneumococcal Infections / Q000188:drug therapy / Q000382:microbiology*; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D013997:Time Factors