title: Molecular epidemiology of bovine noroviruses in South Korea.
abstract: Since the prevalence of bovine norovirus (BNoV) and their genetic diversity have only been reported in the USA, England, Germany and The Netherlands, this study examined the prevalence and genetic diversity of BNoVs in diarrheic calves in South Korea using 645 diarrheic fecal specimens from calves by RT-PCR and nested PCR assays. Overall, 9.3% of the diarrheic fecal samples tested positive for BNoVs by either RT-PCR or nested PCR, of which 5.9% samples also tested positive for other enteric pathogens including the bovine coronavirus, bovine viral diarrhea virus, bovine torovirus, bovine groups A, B and C rotaviruses, bovine enteric Nebraska-like calicivirus and Escherichia coli. The genetic diversity was determined by direct sequencing of the partial RdRp region of 12 BNoVs detected from the fecal samples by nested PCR. Among the BNoVs examined, one Korean BNoV strain had the highest nucleotide (86.8%) and amino acid (99.1%) identity with the genotype 1 BNoV (GIII-1) strain, while the remaining 11 Korean BNoVs shared a higher nucleotide (88.0-90.5%) and amino acid (93.5-99.1%) identity with the genotype 2 BNoV (GIII-2) strains. The phylogenetic data for the nucleotide and amino acid sequences also demonstrated that one Korean BNoV strain clustered with GIII-1 but the remaining eleven strains clustered with GIII-2. In conclusion, BNoV infections are endemic and there are two distinct genotypes with GIII-2 being the main genotype circulating in the calf population in South Korea.
authors.affiliation: Bio-therapy Human Resources Center, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, South Korea.
authors.forename: Sang-Ik
authors.initials: SI
authors.lastname: Park
authors.forename: Cheol
authors.initials: C
authors.lastname: Jeong
authors.forename: Ha-Hyun
authors.initials: HH
authors.lastname: Kim
authors.forename: Sung-Hee
authors.initials: SH
authors.lastname: Park
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Park
authors.forename: Bang-Hun
authors.initials: BH
authors.lastname: Hyun
authors.forename: Dong-Kun
authors.initials: DK
authors.lastname: Yang
authors.forename: Sang-Ki
authors.initials: SK
authors.lastname: Kim
authors.forename: Mun-Il
authors.initials: MI
authors.lastname: Kang
authors.forename: Kyoung-Oh
authors.initials: KO
authors.lastname: Cho
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D017250:Caliciviridae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D016000:Cluster Analysis; D003967:Diarrhea / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary; D005243:Feces / Q000821:virology; D005759:Gastroenteritis / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary; D014644:Genetic Variation; D005838:Genotype; D007723:Korea / Q000453:epidemiology; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D029322:Norovirus / Q000145:classification* / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D012680:Sensitivity and Specificity