title: Molecular epidemiology of noroviruses associated with sporadic gastroenteritis in children in Novosibirsk, Russia, 2003-2012.
abstract: Noroviruses (NoVs) are an important cause of acute gastroenteritis worldwide. To monitor the molecular epidemiology of NoVs genogroup II (GII) in Novosibirsk, Russia, a total of 10,198 stool samples from young children hospitalized with acute gastroenteritis and two asymptomatic comparison groups were collected from 2003 to 2012. All samples were screened for the presence of NoV GII, rotavirus, and astrovirus by RT-PCR. The prevalence of NoV in gastroenteritis cases was 13.1%, varying from 7.1% to 21.3% in different seasons. Rotavirus and/or astrovirus were detectable in 25% of the NoV-positive samples. NoV was detected throughout the year with a seasonal increase during winter months. Based on sequence analysis of regions D and/or C within the VP1 gene, 892 identified NoV strains were divided into nine genotypes—GII.3 (51%), GII.4 (44%), GII.6 (2%), as well as GII.1, GII.2, GII.5, GII.7, GII.16, and GII.21 (totally, 3%). The prevalence of NoV in the comparison groups was considerably lower (∼2.5%); only GII.4 (n = 6), GII.21 (n = 2) and GII.1 (n = 1) genotypes were revealed. Based on phylogenetic analysis of the ORF1/ORF2 junction region sequences, GII.P21/GII.3 recombinant and GII.P4/GII.4 were prevalent genotypes (totally, 93%) and their ratio changed every season. The median age of children with NoV infection was 6.6 months (range, <1-35 months), but it was different depending on NoV genotype. Children infected with the NoV GII.3 were younger (median 6.2 months) than GII.4-positive patients (median 9.1 months). This is the first long-term systematic study of NoV molecular epidemiology in Russia.
authors.affiliation: Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.
authors.forename: Elena V
authors.initials: EV
authors.lastname: Zhirakovskaia
authors.forename: Artem Yu
authors.initials: AY
authors.lastname: Tikunov
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Bodnev
authors.forename: Vera V
authors.initials: VV
authors.lastname: Klemesheva
authors.forename: Sergey V
authors.initials: SV
authors.lastname: Netesov
authors.forename: Nina V
authors.initials: NV
authors.lastname: Tikunova
mesh_terms: D017250:Caliciviridae Infections / Q000453:epidemiology* / Q000821:virology*; D002675:Child, Preschool; D016000:Cluster Analysis; D005243:Feces / Q000821:virology; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology* / Q000821:virology*; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D029322:Norovirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D010802:Phylogeny; D015995:Prevalence; D012367:RNA, Viral / Q000235:genetics; D012426:Russia / Q000453:epidemiology; D012621:Seasons; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: D012367:RNA, Viral; D015678:Viral Structural Proteins
keywords: epidemiology; genotype; norovirus group II; phylogenetic analysis; sequencing