title: Identification of a novel cosavirus species in faeces of children and its relationship with acute gastroenteritis in China.
abstract: OBJECTIVE
  To assess the prevalence of human cosavirus (HCosV) in China and to determine the association of a novel HCosV (Cosa-CHN) with acute gastroenteritis (AGE).
  
  
  METHODS
  A case-control study with 461 paired stool samples from diarrhoea and healthy children was conducted. Real-time PCR and nested PCR were used to detect the HCosVs. Rapid amplification of cDNA ends was used to obtain the ends of the Cosa-CHN.
  
  
  RESULTS
  Known HCosVs were detected in two control samples, while Cosa-CHN was detected in eight (1.7%) and six (1.3%) of the case and control samples respectively. The complete genome of Cosa-CHN comprises 7213 bp. The P1 and P2 regions of the Cosa-CHN were closely related to those of HCosV B, while the P3 region was most similar to that of HCosV D, albeit with low amino acid identities (66 and 67% respectively). Phylogenetic analyses of the polyprotein and partial VP3/VP1 regions indicated that Cosa-CHN could be classified as a novel species (tentatively named HCosV G) in cosavirus. There was no significant difference in detection rate (p 0.59) or mean virus load (p 0.43) of Cosa-CHN between the cases and controls. Statistical analysis revealed no association between Cosa-CHN and AGE (p 0.76), and the virus did not exacerbate clinical symptoms.
  
  
  CONCLUSIONS
  A low prevalence of HCosV was detected, but a novel Cosavirus species was found in children with and without gastroenteritis in this study. The evidence did not support a causative role for the novel virus in paediatric AGE.
authors.affiliation: Institute for Viral Diseases Control and Prevention, Beijing, China.
authors.forename: J-M
authors.initials: JM
authors.lastname: Yu
authors.affiliation: Institute for Viral Diseases Control and Prevention, Beijing, China.
authors.forename: Y-Y
authors.initials: YY
authors.lastname: Ao
authors.affiliation: Institute for Viral Diseases Control and Prevention, Beijing, China.
authors.forename: L-L
authors.initials: LL
authors.lastname: Li
authors.affiliation: Institute for Viral Diseases Control and Prevention, Beijing, China. Electronic address: zhaojund@126.com.
authors.forename: Z-J
authors.initials: ZJ
authors.lastname: Duan
mesh_terms: D000818:Animals; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D005243:Feces / Q000821:virology*; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D007223:Infant; D008297:Male; D010802:Phylogeny; D010849:Picornaviridae / Q000145:classification* / Q000302:isolation & purification*; D010850:Picornaviridae Infections / Q000453:epidemiology / Q000821:virology*; D016133:Polymerase Chain Reaction; D015995:Prevalence; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
keywords: Acute gastroenteritis; Case–control study; Children; Diarrhoea; Novel cosavirus