title: [Analysis of infection status and pathogenic features of human metapneumovirus among children in Hangzhou between year 2009 and 2011].
abstract: OBJECTIVE
  To study the infection status and pathogenic features of human metapneumovirus (hMPV) among children with acute respiratory tract infection in Hangzhou.
  
  
  METHODS
  A total of 372 children less than 14 years old with acute respiratory tract infections were recruited as subjects from the pediatric clinic or intensive care unit (ICU) of 3 hospitals in Hangzhou during November 2009 to January 2010, and November 2010 to January 2011. A total of 372 specimens were collected, including 351 respiratory swab, 9 nasopharyngeal aspirate material, 8 endotracheal aspirate material and 4 sputum. The total nucleic acid was then extracted from the specimens, and the nucleoprotein (N) gene of hMPV was amplified by RT-PCR, whose positive products were sequenced and analyzed. Africa green monkey kidney cells (Vero-E6) were applied to culture hMPV among the positive samples; meanwhile fluorescence quantitative RT-PCR was adopted to test other respiratory virus infection.
  
  
  RESULTS
  Out of 372 patients, 42 (11.2%) were positive for N gene of hMPV. The positive rate of hMPV among boys was 11.5% (26/226), and correspondingly 10.9% (16/146) among girls. The difference showed no statistical significance (χ(2) = 0.026, P > 0.05). The youngest patient was only 2 month-old and the eldest patient was 14 years old. The median of the patients' age was 24 months. Fifteen positive samples amplified by RT-PCR were sequenced, and all turned out to be subtype B1; whose similarity to GD165 found in Guangdong was 98.1% - 99.5% and similarity to BJ1897 in Beijing was 87.8% - 89.2%. The co-infection rate between hMPV and other respiratory virus was 45.2% (19/42); most of which was between hMPV and respiratory syncytial virus, whose rate at 26.1% (11/42).
  
  
  CONCLUSIONS
  hMPV was the single genotype relevant with the acute respiratory tract infection disease among children in Hangzhou district; however, the co-infection with other respiratory virus did exist.
authors.affiliation: Microbiology Laboratory, Hangzhou Center for Disease Contorl and Prevention, Hangzhou 310021, China. kouyu09@126.com
authors.forename: Yu
authors.initials: Y
authors.lastname: Kou
authors.forename: Xin-fen
authors.initials: XF
authors.lastname: Yu
authors.forename: Jin-cao
authors.initials: JC
authors.lastname: Pan
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Yan-ping
authors.initials: YP
authors.lastname: Wen
authors.forename: Yin-yan
authors.initials: YY
authors.lastname: Zhou
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D029121:Metapneumovirus / Q000235:genetics* / Q000302:isolation & purification; D018184:Paramyxoviridae Infections / Q000453:epidemiology / Q000821:virology*; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000821:virology*