title: [Molecular characteristics of acute gastroenteritis outbreaks caused by norovirus, in Jiangsu province].
abstract: OBJECTIVE
  To study both the epidemiologic and molecular characteristics of outbreaks caused by norovirus (NoV) with its variants, in Jiangsu.
  
  
  METHODS
  67 specimens from seven gastroenteritis outbreaks were collected from October 2012 to March 2013 in Jiangsu. NoV gene group was detected by Real-Time RT-PCR. NoV portions of RdRp gene and VP1 gene were amplified under RT-PCR.
  
  
  RESULTS
  Seven gastroenteritis outbreaks were caused by NoV. Among all the fecal specimens,45 (67.2%) showed positive to NoV G II. Study on the genotype was conducted through analyzing the nucleotide sequence of RdRp gene. Based on the RdRp region, 7 strains appeared to be G II, with 3 and 38 strains belonged to G II.4--Sydney variants. Results from phylogenetic analysis confirmed that 38 variants shared 99% identity with G II.4--Sydney. We also amplified the VP1 genes from 6 variants and comparing with 9 epidemic strains on the sequence amino acid sequence. All the strains showed mutation in amino acid sequence at some key sites which were closely related to the forming of neutralizing epitopes.
  
  
  CONCLUSIONS
  The short interval periods between all 7 NoV outbreaks with identical viral strain indicated the emergence of a new NoV variant in Jiangsu province,that had caused a number of epidemics abroad. Results from our study suggested that the development of monitoring programs on this novel G II.4--Sydney variant should be a part of the NoV surveillance in Jiangsu province or even in the country.
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Jian-Guang
authors.initials: JG
authors.lastname: Fu
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ai
authors.affiliation: National Institute for Viral Diseases Control and Prevention, Chinese Center for Disease Control and Prevention.
authors.forename: Miao
authors.initials: M
authors.lastname: Jin
authors.affiliation: Suzhou Center of Disease Control and Prevention.
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.affiliation: Wuxi Center for Disease Control and Prevention.
authors.forename: Dan
authors.initials: D
authors.lastname: Sha
authors.affiliation: Changzhou Center for Disease Control and Prevention.
authors.forename: Ping
authors.initials: P
authors.lastname: Yao
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Qi
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Chang-Jun
authors.initials: CJ
authors.lastname: Bao
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Ye-Fei
authors.initials: YF
authors.lastname: Zhu
authors.affiliation: Key Lab of Enteric Pathogenic Microbiology, Ministry of Health, Jiangsu Provincial Center of Disease Control and Prevention, Nanjing 210009, China.
authors.forename: Fen-Yang
authors.initials: FY
authors.lastname: Tang
mesh_terms: D000595:Amino Acid Sequence; D017250:Caliciviridae Infections / Q000453:epidemiology / Q000821:virology*; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology*; D005838:Genotype; D006801:Humans; D029322:Norovirus / Q000235:genetics*; D010802:Phylogeny; D012367:RNA, Viral
chemical_list: D012367:RNA, Viral