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Sample records for gii-4 norovirus variant-specific

  1. Immunogenetic Mechanisms Driving Norovirus GII.4 Antigenic Variation

    PubMed Central

    Donaldson, Eric F.; Corti, Davide; Swanstrom, Jesica; Debbink, Kari; Lanzavecchia, Antonio; Baric, Ralph S.

    2012-01-01

    Noroviruses are the principal cause of epidemic gastroenteritis worldwide with GII.4 strains accounting for 80% of infections. The major capsid protein of GII.4 strains is evolving rapidly, resulting in new epidemic strains with altered antigenic potentials. To test if antigenic drift may contribute to GII.4 persistence, human memory B cells were immortalized and the resulting human monoclonal antibodies (mAbs) characterized for reactivity to a panel of time-ordered GII.4 virus-like particles (VLPs). Reflecting the complex exposure history of the volunteer, human anti-GII.4 mAbs grouped into three VLP reactivity patterns; ancestral (1987–1997), contemporary (2004–2009), and broad (1987–2009). NVB 114 reacted exclusively to the earliest GII.4 VLPs by EIA and blockade. NVB 97 specifically bound and blocked only contemporary GII.4 VLPs, while NBV 111 and 43.9 exclusively reacted with and blocked variants of the GII.4.2006 Minerva strain. Three mAbs had broad GII.4 reactivity. Two, NVB 37.10 and 61.3, also detected other genogroup II VLPs by EIA but did not block any VLP interactions with carbohydrate ligands. NVB 71.4 cross-neutralized the panel of time-ordered GII.4 VLPs, as measured by VLP-carbohydrate blockade assays. Using mutant VLPs designed to alter predicted antigenic epitopes, two evolving, GII.4-specific, blockade epitopes were mapped. Amino acids 294–298 and 368–372 were required for binding NVB 114, 111 and 43.9 mAbs. Amino acids 393–395 were essential for binding NVB 97, supporting earlier correlations between antibody blockade escape and carbohydrate binding variation. These data inform VLP vaccine design, provide a strategy for expanding the cross-blockade potential of chimeric VLP vaccines, and identify an antibody with broadly neutralizing therapeutic potential for the treatment of human disease. Moreover, these data support the hypothesis that GII.4 norovirus evolution is heavily influenced by antigenic variation of neutralizing epitopes

  2. Recombination within the Pandemic Norovirus GII.4 Lineage

    PubMed Central

    Eden, John-Sebastian; Tanaka, Mark M.; Boni, Maciej F.; Rawlinson, William D.

    2013-01-01

    Norovirus (NoV) is the leading cause of viral gastroenteritis globally. Since 1996, NoV variants of a single genetic lineage, GII.4, have been associated with at least six pandemics of acute gastroenteritis and caused between 62 and 80% of all NoV outbreaks. The emergence of these novel GII.4 variants has been attributed to rapid evolution and antigenic variation in response to herd immunity; however, the contribution of recombination as a mechanism facilitating emergence is increasingly evident. In this study, we sought to examine the role that intragenotype recombination has played in the emergence of GII.4 variants. Using a genome-wide approach including 25 complete genome sequences generated as part of this study, 11 breakpoints were identified within the NoV GII.4 lineage. The breakpoints were located at three recombination hot spots: near the open reading frame 1/2 (ORF1/2) and ORF2/3 overlaps, as well as within ORF2, which encodes the viral capsid, at the junction of the shell and protruding domains. Importantly, we show that recombination contributed to the emergence of the recent pandemic GII.4 variant, New Orleans 2009, and a newly identified GII.4 variant, termed Sydney 2012. Reconstructing the evolutionary history of the GII.4 lineage reveals the widespread impact of both inter- and intragenotype recombination on the emergence of many GII.4 variants. Lastly, this study highlights the many challenges in the identification of true recombination events and proposes that guidelines be applied for identifying NoV recombinants. PMID:23536665

  3. Mechanisms of GII.4 Norovirus Persistence in Human Populations

    PubMed Central

    LoBue, Anna D; Cannon, Jennifer L; Zheng, Du-Ping; Vinje, Jan; Baric, Ralph S

    2008-01-01

    Background Noroviruses are the leading cause of viral acute gastroenteritis in humans, noted for causing epidemic outbreaks in communities, the military, cruise ships, hospitals, and assisted living communities. The evolutionary mechanisms governing the persistence and emergence of new norovirus strains in human populations are unknown. Primarily organized by sequence homology into two major human genogroups defined by multiple genoclusters, the majority of norovirus outbreaks are caused by viruses from the GII.4 genocluster, which was first recognized as the major epidemic strain in the mid-1990s. Previous studies by our laboratory and others indicate that some noroviruses readily infect individuals who carry a gene encoding a functional alpha-1,2-fucosyltransferase (FUT2) and are designated “secretor-positive” to indicate that they express ABH histo-blood group antigens (HBGAs), a highly heterogeneous group of related carbohydrates on mucosal surfaces. Individuals with defects in the FUT2 gene are termed secretor-negative, do not express the appropriate HBGA necessary for docking, and are resistant to Norwalk infection. These data argue that FUT2 and other genes encoding enzymes that regulate processing of the HBGA carbohydrates function as susceptibility alleles. However, secretor-negative individuals can be infected with other norovirus strains, and reinfection with the GII.4 strains is common in human populations. In this article, we analyze molecular mechanisms governing GII.4 epidemiology, susceptibility, and persistence in human populations. Methods and Findings Phylogenetic analyses of the GII.4 capsid sequences suggested an epochal evolution over the last 20 y with periods of stasis followed by rapid evolution of novel epidemic strains. The epidemic strains show a linear relationship in time, whereby serial replacements emerge from the previous cluster. Five major evolutionary clusters were identified, and representative ORF2 capsid genes for each

  4. Serological Correlates of Protection against a GII.4 Norovirus

    PubMed Central

    Bernstein, David I.; Lyon, G. Marshall; Treanor, John J.; Al-Ibrahim, Mohamed S.; Graham, David Y.; Vinjé, Jan; Jiang, Xi; Gregoricus, Nicole; Frenck, Robert W.; Moe, Christine L.; Chen, Wilbur H.; Ferreira, Jennifer; Barrett, Jill; Opekun, Antone R.; Estes, Mary K.; Borkowski, Astrid; Baehner, Frank; Goodwin, Robert; Edmonds, Anthony; Mendelman, Paul M.

    2015-01-01

    Noroviruses are the leading cause of acute gastroenteritis worldwide, and norovirus vaccine prevention strategies are under evaluation. The immunogenicity of two doses of bivalent genogroup 1 genotype 1 (GI.1)/GII.4 (50 μg of virus-like particles [VLPs] of each strain adjuvanted with aluminum hydroxide and 3-O-desacyl-4′monophosphoryl lipid A [MPL]) norovirus vaccine administered to healthy adults in a phase 1/2 double-blind placebo-controlled trial was determined using virus-specific serum total antibody enzyme-linked immunosorbent assay (ELISA), IgG, IgA, and histoblood group antigen (HBGA)-blocking assays. Trial participants subsequently received an oral live virus challenge with a GII.4 strain, and the vaccine efficacy results were reported previously (D. I. Bernstein et al., J Infect Dis 211:870–878, 2014, doi:10.1093/infdis/jiu497). This report assesses the impact of prechallenge serum antibody levels on infection and illness outcomes. Serum antibody responses were observed in vaccine recipients by all antibody assays, with first-dose seroresponse frequencies ranging from 88 to 100% for the GI.1 antigen and from 69 to 84% for the GII.4 antigen. There was little increase in antibody levels after the second vaccine dose. Among the subjects receiving the placebo, higher prechallenge serum anti-GII.4 HBGA-blocking and IgA antibody levels, but not IgG or total antibody levels, were associated with a lower frequency of virus infection and associated illness. Notably, some placebo subjects without measurable serum antibody levels prechallenge did not become infected after norovirus challenge. In vaccinees, anti-GII.4 HBGA-blocking antibody levels of >1:500 were associated with a lower frequency of moderate-to-severe vomiting or diarrheal illness. In this study, prechallenge serum HBGA antibody titers correlated with protection in subjects receiving the placebo; however, other factors may impact the likelihood of infection and illness after virus exposure. (This

  5. Serological Correlates of Protection against a GII.4 Norovirus.

    PubMed

    Atmar, Robert L; Bernstein, David I; Lyon, G Marshall; Treanor, John J; Al-Ibrahim, Mohamed S; Graham, David Y; Vinjé, Jan; Jiang, Xi; Gregoricus, Nicole; Frenck, Robert W; Moe, Christine L; Chen, Wilbur H; Ferreira, Jennifer; Barrett, Jill; Opekun, Antone R; Estes, Mary K; Borkowski, Astrid; Baehner, Frank; Goodwin, Robert; Edmonds, Anthony; Mendelman, Paul M

    2015-08-01

    Noroviruses are the leading cause of acute gastroenteritis worldwide, and norovirus vaccine prevention strategies are under evaluation. The immunogenicity of two doses of bivalent genogroup 1 genotype 1 (GI.1)/GII.4 (50 μg of virus-like particles [VLPs] of each strain adjuvanted with aluminum hydroxide and 3-O-desacyl-4'monophosphoryl lipid A [MPL]) norovirus vaccine administered to healthy adults in a phase 1/2 double-blind placebo-controlled trial was determined using virus-specific serum total antibody enzyme-linked immunosorbent assay (ELISA), IgG, IgA, and histoblood group antigen (HBGA)-blocking assays. Trial participants subsequently received an oral live virus challenge with a GII.4 strain, and the vaccine efficacy results were reported previously (D. I. Bernstein et al., J Infect Dis 211:870-878, 2014, doi:10.1093/infdis/jiu497). This report assesses the impact of prechallenge serum antibody levels on infection and illness outcomes. Serum antibody responses were observed in vaccine recipients by all antibody assays, with first-dose seroresponse frequencies ranging from 88 to 100% for the GI.1 antigen and from 69 to 84% for the GII.4 antigen. There was little increase in antibody levels after the second vaccine dose. Among the subjects receiving the placebo, higher prechallenge serum anti-GII.4 HBGA-blocking and IgA antibody levels, but not IgG or total antibody levels, were associated with a lower frequency of virus infection and associated illness. Notably, some placebo subjects without measurable serum antibody levels prechallenge did not become infected after norovirus challenge. In vaccinees, anti-GII.4 HBGA-blocking antibody levels of >1:500 were associated with a lower frequency of moderate-to-severe vomiting or diarrheal illness. In this study, prechallenge serum HBGA antibody titers correlated with protection in subjects receiving the placebo; however, other factors may impact the likelihood of infection and illness after virus exposure. (This

  6. Emergence of GII.4 Sydney norovirus in South Korea during the winter of 2012-2013.

    PubMed

    Kim, Hyun Soo; Hyun, Jeongwon; Kim, Han-Sung; Kim, Jae-Seok; Song, Wonkeun; Lee, Kyu Man

    2013-11-28

    Norovirus is the major cause of acute gastroenteritis worldwide. Between November 2012 and June 2013, 1718 stool samples were requested for norovirus antigen testing in the metropolitan areas of South Korea, and 91 samples were genotyped. The norovirus antigen-positive rate peaked at 52.8% in December 2012. [corrected]. A novel norovirus GII.4 variant, GII.4 Sydney 2012, was the most frequently found genotype (60.4%) during this period. This study demonstrates that norovirus activity increased during the winter of 2012-2013 in South Korea and that norovirus GII.4 Sydney 2012 was the cause of the norovirus epidemic during this period.

  7. Epidemiological dynamics of norovirus GII.4 variant New Orleans 2009.

    PubMed

    Medici, Maria Cristina; Tummolo, Fabio; De Grazia, Simona; Calderaro, Adriana; De Conto, Flora; Terio, Valentina; Chironna, Maria; Bonura, Floriana; Pucci, Marzia; Bányai, Kristián; Martella, Vito; Giammanco, Giovanni Maurizio

    2015-09-01

    Norovirus (NoV) is one of the major causes of diarrhoeal disease with epidemic, outbreak and sporadic patterns in humans of all ages worldwide. NoVs of genotype GII.4 cause nearly 80-90 % of all NoV infections in humans. Periodically, some GII.4 strains become predominant, generating major pandemic variants. Retrospective analysis of the GII.4 NoV strains detected in Italy between 2007 and 2013 indicated that the pandemic variant New Orleans 2009 emerged in Italy in the late 2009, became predominant in 2010-2011 and continued to circulate in a sporadic fashion until April 2013. Upon phylogenetic analysis based on the small diagnostic regions A and C, the late New Orleans 2009 NoVs circulating during 2011-2013 appeared to be genetically different from the early New Orleans 2009 strains that circulated in 2010. For a selection of strains, a 3.2 kb genome portion at the 3' end was sequenced. In the partial ORF1 and in the full-length ORF2 and ORF3, the 2011-2013 New Orleans NoVs comprised at least three distinct genetic subclusters. By comparison with sequences retrieved from the databases, these subclusters were also found to circulate globally, suggesting that the local circulation reflected repeated introductions of different strains, rather than local selection of novel viruses. Phylogenetic subclustering did not correlate with changes in residues located in predicted putative capsid epitopes, although several changes affected the P2 domain in epitopes A, C, D and E.

  8. Characterization of GII.4 noroviruses circulating among children with acute gastroenteritis in Pune, India: 2005-2013.

    PubMed

    Kulkarni, Ruta; Patel, Amit; Bhalla, Shilpa; Chhabra, Preeti; Cherian, Sarah; Chitambar, Shobha D

    2016-01-01

    Genogroup II genotype 4 noroviruses (GII.4 NoVs), an important cause of sporadic childhood gastroenteritis worldwide, undergo continuous evolution leading to the periodic emergence of novel variants. The present study was undertaken for surveillance of GII.4 NoVs and identification and characterization of GII.4 variants circulating among children with sporadic gastroenteritis in Pune, India during 2005-2013. Among the 12 GII genotypes detected in the study, GII.4 was predominant. Sequencing and phylogenetic analysis of ORF2 (major capsid protein VP1 gene) of the GII.4 NoVs revealed circulation of seven GII.4 variants, Hunter_2004 (2005-2007), Yerseke_2006a (2006), DenHaag_2006b (2007), Osaka_2007 (2007-2009), Apeldoorn_2007 (2008), New Orleans_2009 (2008-2012) and Sydney_2012 (2013), with the Pune strains grouping with the contemporary global reference strains. The Hunter_2004, Osaka_2007 and New Orleans_2009 variants showed prolonged circulation, with the Hunter_2004 and New Orleans_2009 variants differentiating into temporally separated sub-clusters. Analysis of VP1 sequences and predicted structures of the GII.4 variants identified variant specific amino acid positions, particularly in and near (within 8A(°)) the epitopes A-E, displaying differences in the sequence and physicochemical characteristics of the different variants. Comparison with the reference strains of each of the GII.4 variants revealed up to 11 amino acid substitutions at the variant specific positions in the GII.4 strains from Pune. Amino acid variations were also noted among the strains of the same GII.4 variant in Pune. The strains of different sub-clusters identified in the Hunter_2004 and New Orleans_2009 variants showed differences in sequence and physicochemical properties of either or all of the epitopes A, C and E. The study thus describes the temporal variations and diversity of the GII.4 strains in Pune and emphasizes continuous monitoring and analysis of the GII.4 variants

  9. Emergence of a Norovirus GII.4 Strain Correlates with Changes in Evolving Blockade Epitopes

    PubMed Central

    Lindesmith, Lisa C.; Costantini, Verónica; Swanstrom, Jesica; Debbink, Kari; Donaldson, Eric F.; Vinjé, Jan

    2013-01-01

    The major capsid protein of norovirus GII.4 strains is evolving rapidly, resulting in epidemic strains with altered antigenicity. GII.4.2006 Minerva strains circulated at pandemic levels in 2006 and persisted at lower levels until 2009. In 2009, a new GII.4 variant, GII.4.2009 New Orleans, emerged and since then has become the predominant strain circulating in human populations. To determine whether changes in evolving blockade epitopes correlate with the emergence of the GII.4.2009 New Orleans strains, we compared the antibody reactivity of a panel of mouse monoclonal antibodies (MAbs) against GII.4.2006 and GII.4.2009 virus-like particles (VLPs). Both anti-GII.4.2006 and GII.4.2009 MAbs effectively differentiated the two strains by VLP-carbohydrate ligand blockade assay. Most of the GII.4.2006 MAbs preferentially blocked GII.4.2006, while all of the GII.4.2009 MAbs preferentially blocked GII.4.2009, although 8 of 12 tested blockade MAbs blocked both VLPs. Using mutant VLPs designed to alter predicted antigenic epitopes, binding of seven of the blockade MAbs was impacted by alterations in epitope A, identifying residues 294, 296, 297, 298, 368, and 372 as important antigenic sites in these strains. Convalescent-phase serum collected from a GII.4.2009 outbreak confirmed the immunodominance of epitope A, since alterations of epitope A affected serum reactivity by 40%. These data indicate that the GII.4.2009 New Orleans variant has evolved a key blockade epitope, possibly allowing for at least partial escape from protective herd immunity and provide epidemiological support for the utility of monitoring changes in epitope A in emergent strain surveillance. PMID:23269783

  10. Characterization of a Novel Conformational GII.4 Norovirus Epitope: Implications for Norovirus-Host Interactions

    PubMed Central

    Carmona-Vicente, Noelia; Vila-Vicent, Susana; Allen, David; Gozalbo-Rovira, Roberto; Iturriza-Gómara, Miren

    2016-01-01

    ABSTRACT Human noroviruses (NoVs) are the main etiological agents of acute gastroenteritis worldwide. While NoVs are highly diverse (more than 30 genotypes have been detected in humans), during the last 40 years most outbreaks and epidemics have been caused by GII.4 genotype strains, raising questions about their persistence in the population. Among other potential explanations, immune evasion is considered to be a main driver of their success. In order to study antibody recognition and evasion in detail, we analyzed a conformational epitope recognized by a monoclonal antibody (3C3G3) by phage display, site-directed mutagenesis, and surface plasmon resonance. Our results show that the predicted epitope is composed of 11 amino acids within the P domain: P245, E247, I389, Q390, R397, R435, G443, Y444, P445, N446, and D448. Only two of them, R397 and D448, differ from the homologous variant (GII.4 Den-Haag_2006b) and from a previous variant (GII.4 VA387_1996) that is not recognized by the antibody. A double mutant derived from the VA387_1996 variant containing both changes, Q396R and N447D, is recognized by the 3C3G3 monoclonal antibody, confirming the participation of the two sites in the epitope recognized by the antibody. Furthermore, a single change, Q396R, is able to modify the histo-blood group antigen (HBGA) recognition pattern. These results provide evidence that the epitope recognized by the 3C3G3 antibody is involved in the virus-host interactions, both at the immunological and at the receptor levels. IMPORTANCE Human noroviruses are the main cause of viral diarrhea worldwide in people of all ages. Noroviruses can infect individuals who had been previously exposed to the same or different norovirus genotypes. Norovirus genotype GII.4 has been reported to be most prevalent during the last 40 years. In the present study, we describe a novel viral epitope identified by a monoclonal antibody and located within the highly diverse P domain of the capsid protein

  11. Complete Genome Sequence of Human Norovirus GII.4_2006b, a Variant of Minerva 2006.

    PubMed

    Yang, Zhihui; Mammel, Mark K; Kulka, Michael

    2016-01-28

    In 2006, the National Calicivirus Laboratory at the U.S. Centers for Disease Control and Prevention (CDC) confirmed multistate outbreaks of norovirus infection and identified two new GII.4 norovirus strains (Minerva and Laurens) through partial sequencing of the major capsid (VP1) gene. Here, we report the first complete genome sequence of the GII.4 Minerva isolate. Copyright © 2016 Yang et al.

  12. Emergence of the GII-4 Norovirus Sydney2012 Strain in England, Winter 2012–2013

    PubMed Central

    Allen, David J.; Adams, Natalie L.; Aladin, Farah; Harris, John P.; Brown, David W. G.

    2014-01-01

    Norovirus is the commonest cause of acute gastrointestinal disease and is the main aetiological agent of outbreaks of gastroenteritis, particularly in semi-closed environments. Norovirus infections in England typically peak between December and March each year. The most commonly detected norovirus strains belong to the genetically diverse genogroup-II genotype-4 (GII-4) genocluster and in the previous two norovirus winter seasons the majority of GII-4 strains in circulation worldwide have been genetically similar to the GII-4 strain New Orleans 1805/2009/USA. At the beginning of the 2012/13 season a genetically distinct GII-4 strain (Sydney 2012/NSW0514/2012/AU) was described which emerged worldwide during the winter of 2012/13. Here we describe the emergence of norovirus strains genetically related to Sydney2012 in England during the 2012/13 season to replace NewOrleans2009 strains as the most commonly detected variant of GII-4 norovirus in England. Furthermore, we demonstrate that whilst the emergence of Sydney2012 coincided with an early peak in the number of norovirus outbreaks, there was not an overall increase in norovirus activity compared to the previous season. Finally, we show that the Sydney2012 strain is associated with distinct genetic changes compared to the NewOrleans2009 strain, and these changes may have contributed to the emergence of the Sydney2012 strain. PMID:24551201

  13. Antigenic Relatedness of Norovirus GII.4 Variants Determined by Human Challenge Sera

    PubMed Central

    Dai, Ying-Chun; Zhang, Xu-Fu; Xia, Ming; Tan, Ming; Quigley, Christina; Lei, Wen; Fang, Hao; Zhong, Weiming; Lee, Bonita; Pang, Xiaoli; Nie, Jun; Jiang, Xi

    2015-01-01

    The GII.4 noroviruses (NoVs) are a single genotype that is responsible for over 50% of NoV gastroenteritis epidemics worldwide. However, GII.4 NoVs have been found to undergo antigenic drifts, likely selected by host herd immunity, which raises an issue for vaccine strategies against NoVs. We previously characterized GII.4 NoV antigenic variations and found significant levels of antigenic relatedness among different GII.4 variants. Further characterization of the genetic and antigenic relatedness of recent GII.4 variants (2008b and 2010 cluster) was performed in this study. The amino acid sequences of the receptor binding interfaces were highly conserved among all GII.4 variants from the past two decades. Using serum samples from patients enrolled in a GII.4 virus challenge study, significant cross-reactivity between major GII.4 variants from 1998 to 2012 was observed using enzyme-linked immunosorbent assays and HBGA receptor blocking assays. The overall abilities of GII.4 NoVs to bind to the A/B/H HBGAs were maintained while their binding affinities to individual ABH antigens varied. These results highlight the importance of human HBGAs in NoV evolution and how conserved antigenic types impact vaccine development against GII.4 variants. PMID:25915764

  14. Complete nucleotide sequence analysis of the norovirus GII.4 Sydney variant in South Korea.

    PubMed

    Park, Ji-Sun; Lee, Sung-Geun; Jin, Ji-Young; Cho, Han-Gil; Jheong, Weon-Hwa; Paik, Soon-Young

    2015-01-01

    Norovirus is the primary cause of acute gastroenteritis in individuals of all ages. In Australia, a new strain of norovirus (GII.4) was identified in March 2012, and this strain has spread rapidly around the world. In August 2012, this new GII.4 strain was identified in patients in South Korea. Therefore, to examine the characteristics of the epidemic norovirus GII.4 2012 variant in South Korea, we conducted KM272334 full-length genomic analysis. The genome of the gg-12-08-04 strain consisted of 7,558 bp and contained three open reading frame (ORF) composites throughout the whole genome: ORF1 (5,100 bp), ORF2 (1,623 bp), and ORF3 (807 bp). Phylogenetic analyses showed that gg-12-08-04 belonged to the GII.4 Sydney 2012 variant, sharing 98.92% nucleotide similarity with this variant strain. According to SimPlot analysis, the gg-12-08-04 strain was a recombinant strain with breakpoint at the ORF1/2 junction between Osaka 2007 and Apeldoorn 2008 strains. This study is the first report of the complete sequence of the GII.4 Sydney 2012 strain in South Korea. Therefore, this may represent the standard sequence of the norovirus GII.4 2012 variant in South Korea and could therefore be useful for the development of norovirus vaccines.

  15. Complete Nucleotide Sequence Analysis of the Norovirus GII.4 Sydney Variant in South Korea

    PubMed Central

    Park, Ji-Sun; Lee, Sung-Geun; Cho, Han-Gil; Jheong, Weon-Hwa; Paik, Soon-Young

    2015-01-01

    Norovirus is the primary cause of acute gastroenteritis in individuals of all ages. In Australia, a new strain of norovirus (GII.4) was identified in March 2012, and this strain has spread rapidly around the world. In August 2012, this new GII.4 strain was identified in patients in South Korea. Therefore, to examine the characteristics of the epidemic norovirus GII.4 2012 variant in South Korea, we conducted KM272334 full-length genomic analysis. The genome of the gg-12-08-04 strain consisted of 7,558 bp and contained three open reading frame (ORF) composites throughout the whole genome: ORF1 (5,100 bp), ORF2 (1,623 bp), and ORF3 (807 bp). Phylogenetic analyses showed that gg-12-08-04 belonged to the GII.4 Sydney 2012 variant, sharing 98.92% nucleotide similarity with this variant strain. According to SimPlot analysis, the gg-12-08-04 strain was a recombinant strain with breakpoint at the ORF1/2 junction between Osaka 2007 and Apeldoorn 2008 strains. This study is the first report of the complete sequence of the GII.4 Sydney 2012 strain in South Korea. Therefore, this may represent the standard sequence of the norovirus GII.4 2012 variant in South Korea and could therefore be useful for the development of norovirus vaccines. PMID:25688356

  16. Genetic mapping of a highly variable norovirus GII.4 blockade epitope: potential role in escape from human herd immunity.

    PubMed

    Debbink, Kari; Donaldson, Eric F; Lindesmith, Lisa C; Baric, Ralph S

    2012-01-01

    Noroviruses account for 96% of viral gastroenteritis cases worldwide, with GII.4 strains responsible >80% of norovirus outbreaks. Histo-blood group antigens (HBGAs) are norovirus binding ligands, and antigenic and preferential HBGA binding profiles vary over time as new GII.4 strains emerge. The capsid P2 subdomain facilitates HBGA binding, contains neutralizing antibody epitopes, and likely evolves in response to herd immunity. To identify amino acids regulating HBGA binding and antigenic differences over time, we created chimeric virus-like particles (VLPs) between the GII.4-1987 and GII.4-2006 strains by exchanging amino acids in putative epitopes and characterized their antigenic and HBGA binding profiles using anti-GII.4-1987 and -2006 mouse monoclonal antibodies (MAbs) and polyclonal sera, 1988 outbreak human sera, and synthetic HBGAs. The exchange of amino acids 393 to 395 between GII.4-1987 and GII.4-2006 resulted in altered synthetic HBGA binding compared to parental strains. Introduction of GII.4-1987 residues 294, 297 to 298, 368, and 372 (epitope A) into GII.4-2006 resulted in reactivity with three anti-GII.4-1987 MAbs and reduced reactivity with four anti-GII.4-2006 MAbs. The three anti-GII.4-1987 MAbs also blocked chimeric VLP-HBGA interaction, while an anti-GII.4-2006 blocking antibody did not, indicating that epitope A amino acids comprise a potential neutralizing epitope for GII.4-1987 and GII.4-2006. We also tested GII.4-1987-immunized mouse polyclonal sera and 1988 outbreak human sera for the ability to block chimeric VLP-HBGA interaction and found that epitope A amino acids contribute significantly to the GII.4-1987 blockade response. Our data provide insights that help explain the emergence of new GII.4 epidemic strains over time, may aid development of norovirus therapeutics, and may help predict the emergence of future epidemic strains.

  17. [Epidemiological characteristics of norovirus variant of GII.4 Sydney and the outbreaks caused by norovirus variant of GII.4 Sydney in Guangdong province, 2012-2014].

    PubMed

    Sun, Limei; Li, Hui; Tan, Xiaohua; Mo, Yanling; Guo, Lili; Yang, Fen; He, Jianfeng; Ke, Changwen; Zhang, Yonghui

    2015-07-01

    To analyze epidemiological characteristics of norovirus variant of GII.4 Sydney from January 2012 to June 2014 in sentinel hospitals of Guangdong province, as well as the outbreaks caused by norovirus variant of GII.4 Sydney. During January 2012 to June 2014, a total of 10 750 fecal samples were obtained from 22 hospitals of surveillance sites in Guangdong province. Those samples were sent to the local municipal CDCs for extracting and detecting norovirus nucleic acid. Then, all the positive samples were delivered to Guangdong provincial CDC that used Random Number Method to draw 855 positive samples for norovirus genotyping, and 690 samples were successfully sequenced. Chi-square tests were used to compare norovirus infection status of diarrhea cases in different age groups as well as during different periods. Epidemiological data of 13 outbreaks which were caused by norovirus variant of GII.4 Sydney from January 2012 to June 2014 were collected from the Public Health Emergency Management Information System of Guangdong Province, and the epidemiological characteristics were analyzed. The norovirus variant of GII.4 Sydney was first detected in August 2012 and the detection rate was 13/15 in November 2012. During November 2012 to January 2013 (period T1), the norovirus positive rate of each month was 23.8% (100/421), 15.9% (61/383) and 19.2% (95/495), respectively. During November 2013 to January 2014 (period T2), the norovirus positive rate of each month was 17.0% (90/529), 8.7% (37/426) and 11.2% (46/409), respectively which were significantly lower than that of period T1 (χ² alue was 6.65, 9.93 and 10.74. P value was 0.010, 0.002, and 0.001, respectively). In period T1, the norovirus positive rate of people ages 15 and older was 26.3% (143/543) and the rate of people under 15 was 14.9% (113/756) (χ² = 2.90, P < 0.001). In period T2, the norovirus positive rate of people ages 15 and older was 10.1% (52/516) and the rate of people under 15 (14.3% (121/848)) (

  18. Comparative efficacy of seven hand sanitizers against murine norovirus, feline calicivirus, and GII.4 norovirus.

    PubMed

    Park, Geun Woo; Barclay, Leslie; Macinga, David; Charbonneau, Duane; Pettigrew, Charles A; Vinjé, Jan

    2010-12-01

    Contaminated hands or inanimate surfaces can act as a source of infection during outbreaks of human norovirus infection. We evaluated the virucidal efficacy of seven hand sanitizers containing various active ingredients, such as ethanol, triclosan, and chlorhexidine, and compared their effectiveness against feline calicivirus (FCV), murine norovirus (MNV), and a GII.4 norovirus fecal extract. We also tested the efficacy of 50, 70, and 90% of ethanol and isopropanol. Reduction of viral infectivity was measured by plaque assay, and the number of genomic copies was determined with a TaqMan real-time reverse transcription PCR assay. Based on the results of a quantitative suspension test, only one ethanol-based product (72% ethanol, pH 2.9) and one triclosan-based product (0.1% triclosan, pH 3.0) reduced the infectivity of both MNV and FCV (by >2.6 and ≥3.4 log units, respectively). Four of the seven products were effective against either MNV or FCV, whereas chlorhexidine was ineffective against both viruses. For these hand sanitizers, no correlation was found between reduced infectivity and decline of viral RNA. Ethanol and isopropanol concentrations ≥70% reduced the infectivity of MNV by ≥2.6 log units, whereas 50 and 70% ethanol reduced the infectivity of FCV by ≥2.2 log units after exposure for 5 min. The susceptibility of FCV to low pH and the relative high susceptibility of MNV to alcohols suggest that both surrogate viruses should be considered for in vitro testing of hand sanitizers.

  19. Immunogenicity and Specificity of Norovirus Consensus GII.4 Virus-like Particles in Monovalent and Bivalent Vaccine Formulations

    PubMed Central

    Parra, Gabriel I.; Bok, Karin; Taylor, Ross; Haynes, Joel; Sosnovtsev, Stanislav V.; Richardson, Charles; Green, Kim Y.

    2012-01-01

    Noroviruses, a major cause of acute gastroenteritis worldwide, present antigenic diversity that must be considered for the development of an effective vaccine. In this study, we explored approaches to increase the broad reactivity of virus-like particle (VLP) norovirus vaccine candidates. The immunogenicity of a GII.4 “Consensus” VLP that was engineered from sequences of three genetically distinct naturally-occurring GII.4 strains was examined for its ability to induce cross-reactive immune responses against different clusters of GII.4 noroviruses. Rabbits immunized with GII.4 Consensus VLPs developed high serum antibody titers against VLPs derived from a number of distinct wild-type GII.4 viruses, including some that have been circulating over 30 years. Because the sera exhibited low cross-reactivity with antigenically-distinct GI norovirus strains, we investigated the serum antibody response to a bivalent vaccine formulation containing GI.1 (Norwalk virus) and GII.4 Consensus VLPs that was administered to animals under varying conditions. In these studies, the highest homologous and heterologous antibody titers to the bivalent vaccine were elicited following immunization of animals by the intramuscular route using Alhydrogel (Al(OH)3) as adjuvant. Our data indicate that the use of both genetically-engineered norovirus VLPs that incorporate relevant epitopes from multiple strains and multivalent vaccine formulations increase the breadth of the immune response to diverse variants within a genotype and, thus, prove helpful in the rational design of VLP-based vaccines against human noroviruses. PMID:22469864

  20. Epidemiological investigation of a norovirus GII.4 Sydney outbreak in a China elder care facility.

    PubMed

    Zheng, Qing-ming; Zeng, Hua-tang; Dai, Chuan-wen; Zhang, Shun-xiang; Zhang, Zhen; Mei, Shu-jiang; He, Ya-qing; Ma, Han-wu

    2015-01-01

    An outbreak of norovirus GII.4/Sydney_2012 affected a China elder care facility in December 2012. A total of 39 elderly people and staff met the outbreak case definition. The attack rates in the elderly and the staff were 15.9% (31/195) and 23.2% (19/82), respectively, including 13 asymptomatic cases in the staff. The result of gene sequencing revealed that the outbreak was caused by norovirus GII.4 Sydney. The mode of transmission of this outbreak was proven to be person-to-person. The first case (a self-cared elder) was affected outside the elder care facility and was not isolated after returning. Norovirus was transmitted via close contact among the self-cared elderly. Then, through service-related close contact, the attendants promoted the cross-transmission between the self-cared elderly and the nursed elderly. The virus was also spread among the staff via daily contact. In the elder care facility, the asymptomatic cases in the attendants played an important role in the transmission of norovirus, which deserves high attention.

  1. Effects and Clinical Significance of GII.4 Sydney Norovirus, United States, 2012–2013

    PubMed Central

    Wikswo, Mary; Barclay, Leslie; Brandt, Eric; Storm, William; Salehi, Ellen; DeSalvo, Traci; Davis, Tim; Saupe, Amy; Dobbins, Ginette; Booth, Hillary A.; Biggs, Christianne; Garman, Katie; Woron, Amy M.; Parashar, Umesh D.; Vinjé, Jan; Hall, Aron J.

    2013-01-01

    During 2012, global detection of a new norovirus (NoV) strain, GII.4 Sydney, raised concerns about its potential effect in the United States. We analyzed data from NoV outbreaks in 5 states and emergency department visits for gastrointestinal illness in 1 state during the 2012–13 season and compared the data with those of previous seasons. During August 2012–April 2013, a total of 637 NoV outbreaks were reported compared with 536 and 432 in 2011–2012 and 2010–2011 during the same period. The proportion of outbreaks attributed to GII.4 Sydney increased from 8% in September 2012 to 82% in March 2013. The increase in emergency department visits for gastrointestinal illness during the 2012–13 season was similar to that of previous seasons. GII.4 Sydney has become the predominant US NoV outbreak strain during the 2012–13 season, but its emergence did not cause outbreak activity to substantially increase from that of previous seasons. PMID:23886013

  2. Molecular epidemiology of norovirus associated with gastroenteritis and emergence of norovirus GII.4 variant 2012 in Japanese pediatric patients.

    PubMed

    Thongprachum, Aksara; Chan-it, Wisoot; Khamrin, Pattara; Saparpakorn, Patchreenart; Okitsu, Shoko; Takanashi, Sayaka; Mizuguchi, Masashi; Hayakawa, Satoshi; Maneekarn, Niwat; Ushijima, Hiroshi

    2014-04-01

    In late 2012, an outbreak of acute gastroenteritis due to norovirus variant Sydney_2012 occurred and have been reported from many counties. In this study, we described surveillance study of the incidence of norovirus infections among Japanese pediatric patients in association with gastroenteritis and investigated the antigenic change of the new variant Sydney_2012 circulated in Japanese populations. A total of 2381 fecal specimens collected from children with acute gastroenteritis in Hokkaido, Tokyo, Shizuoka, Kyoto, Osaka, and Saga from 2009 to 2013 were examined for norovirus and further analyzed molecularly. A high proportion (39.3%) of norovirus positive samples and several genotypes were detected. Norovirus GII.4 dominated over other genotypes (71.4%). The Den_Haag_2006b (43.2%) was detected as the predominant variant and co-circulated with New_Orleans_2009 (17.8%) until March 2012. Subsequently, they were displaced by Sydney_2012. The Sydney_2012 variant has been responsible for the majority of norovirus infections in 2012-2013 (85.7%). Although Sydney_2012 variant has a common ancestor with New_Orleans_2009 variant, analysis of P2 sub-domain showed a high level of diversity in comparison with other variants in four amino acid changes at the antigenic sites. The change in particular residue 393 of new variant may affect HBGA recognition. Analysis of noroviruses circulating in the past 4years revealed a change of predominant variant of norovirus GII.4 in each epidemic season. The change of amino acid in putative epitopes may have led the virus escape from the existing herd immunity and explain the increase of new variant outbreaks.

  3. Norovirus GII.4 Detection in Environmental Samples from Patient Rooms during Nosocomial Outbreaks

    PubMed Central

    Hannoun, Charles; Svensson, Lennart; Torén, Kjell; Andersson, Lars-Magnus; Westin, Johan; Bergström, Tomas

    2014-01-01

    Norovirus (NoV) is an important cause of nosocomial gastroenteric outbreaks. This 5-month study was designed to characterize NoV contamination and airborne dispersal in patient rooms during hospital outbreaks. Air vents, overbed tables, washbasins, dust, and virus traps designed to collect charged particles from the air were swabbed to investigate the possibility of NoV contamination in patient rooms during outbreaks in seven wards and in an outbreak-free ward. Symptomatic inpatients were also sampled. Nucleic acid extracts of the samples were examined for NoV RNA using genogroup I (GI) and GII real-time reverse transcription-PCR (RT-PCR). The NoV strains were characterized by RT-PCR, sequencing, and phylogenetic analysis of the RNA-dependent RNA-polymerase-N/S capsid-coding region (1,040 nucleotides [nt]). Patient strains from two outbreaks in one ward were sequenced across the RNA-dependent-RNA-polymerase major capsid-coding region (2.5 kb), including the hypervariable P2 domain. In the outbreak wards, NoV GII was detected in 48 of 101 (47%) environmental swabs and 63 of 108 patients (58%); NoV genotype II.4 was sequenced from 18 environmental samples, dust (n = 8), virus traps (n = 4), surfaces (n = 6), and 56 patients. In contrast, NoV GII was detected in 2 (GII.4) of 28 (7%) environmental samples and in 2 (GII.6 and GII.4) of 17 patients in the outbreak-free ward. Sequence analyses revealed a high degree of similarity (>99.5%, 1,040 nt) between NoV GII.4 environmental and patient strains from a given ward at a given time. The strains clustered on 11 subbranches of the phylogenetic tree, with strong correlations to time and place. The high nucleotide similarity between the NoV GII.4 strains from patients and their hospital room environment provided molecular evidence of GII.4 dispersal in the air and dust; therefore, interventional cleaning studies are justified. PMID:24759712

  4. Norovirus GII.4 detection in environmental samples from patient rooms during nosocomial outbreaks.

    PubMed

    Nenonen, Nancy P; Hannoun, Charles; Svensson, Lennart; Torén, Kjell; Andersson, Lars-Magnus; Westin, Johan; Bergström, Tomas

    2014-07-01

    Norovirus (NoV) is an important cause of nosocomial gastroenteric outbreaks. This 5-month study was designed to characterize NoV contamination and airborne dispersal in patient rooms during hospital outbreaks. Air vents, overbed tables, washbasins, dust, and virus traps designed to collect charged particles from the air were swabbed to investigate the possibility of NoV contamination in patient rooms during outbreaks in seven wards and in an outbreak-free ward. Symptomatic inpatients were also sampled. Nucleic acid extracts of the samples were examined for NoV RNA using genogroup I (GI) and GII real-time reverse transcription-PCR (RT-PCR). The NoV strains were characterized by RT-PCR, sequencing, and phylogenetic analysis of the RNA-dependent RNA-polymerase-N/S capsid-coding region (1,040 nucleotides [nt]). Patient strains from two outbreaks in one ward were sequenced across the RNA-dependent-RNA-polymerase major capsid-coding region (2.5 kb), including the hypervariable P2 domain. In the outbreak wards, NoV GII was detected in 48 of 101 (47%) environmental swabs and 63 of 108 patients (58%); NoV genotype II.4 was sequenced from 18 environmental samples, dust (n = 8), virus traps (n = 4), surfaces (n = 6), and 56 patients. In contrast, NoV GII was detected in 2 (GII.4) of 28 (7%) environmental samples and in 2 (GII.6 and GII.4) of 17 patients in the outbreak-free ward. Sequence analyses revealed a high degree of similarity (>99.5%, 1,040 nt) between NoV GII.4 environmental and patient strains from a given ward at a given time. The strains clustered on 11 subbranches of the phylogenetic tree, with strong correlations to time and place. The high nucleotide similarity between the NoV GII.4 strains from patients and their hospital room environment provided molecular evidence of GII.4 dispersal in the air and dust; therefore, interventional cleaning studies are justified. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  5. Divergent Evolution of Norovirus GII/4 by Genome Recombination from May 2006 to February 2009 in Japan▿ ‡

    PubMed Central

    Motomura, Kazushi; Yokoyama, Masaru; Ode, Hirotaka; Nakamura, Hiromi; Mori, Hiromi; Kanda, Tadahito; Oka, Tomoichiro; Katayama, Kazuhiko; Noda, Mamoru; Tanaka, Tomoyuki; Takeda, Naokazu; Sato, Hironori

    2010-01-01

    Norovirus GII/4 is a leading cause of acute viral gastroenteritis in humans. We examined here how the GII/4 virus evolves to generate and sustain new epidemics in humans, using 199 near-full-length GII/4 genome sequences and 11 genome segment clones from human stool specimens collected at 19 sites in Japan between May 2006 and February 2009. Phylogenetic studies demonstrated outbreaks of 7 monophyletic GII/4 subtypes, among which a single subtype, termed 2006b, had continually predominated. Phylogenetic-tree, bootscanning-plot, and informative-site analyses revealed that 4 of the 7 GII/4 subtypes were mosaics of recently prevalent GII/4 subtypes and 1 was made up of the GII/4 and GII/12 genotypes. Notably, single putative recombination breakpoints with the highest statistical significance were constantly located around the border of open reading frame 1 (ORF1) and ORF2 (P ≤ 0.000001), suggesting outgrowth of specific recombinant viruses in the outbreaks. The GII/4 subtypes had many unique amino acids at the time of their outbreaks, especially in the N-term, 3A-like, and capsid proteins. Unique amino acids in the capsids were preferentially positioned on the outer surface loops of the protruding P2 domain and more abundant in the dominant subtypes. These findings suggest that intersubtype genome recombination at the ORF1/2 boundary region is a common mechanism that realizes independent and concurrent changes on the virion surface and in viral replication proteins for the persistence of norovirus GII/4 in human populations. PMID:20534859

  6. Evolutionary Constraints on the Norovirus Pandemic Variant GII.4_2006b over the Five-Year Persistence in Japan

    PubMed Central

    Sato, Hironori; Yokoyama, Masaru; Nakamura, Hiromi; Oka, Tomoichiro; Katayama, Kazuhiko; Takeda, Naokazu; Noda, Mamoru; Tanaka, Tomoyuki; Motomura, Kazushi

    2017-01-01

    Norovirus GII.4 is a major cause of global outbreaks of viral gastroenteritis in humans, and has evolved by antigenic changes under the constantly changing human herd immunity. Major shift in the pandemic GII.4 strain periodically occurs concomitant with changes in the antigenic capsid protein VP1. However, how the newly emerged strain evolves after the onset of pandemic remains unclear. To address this issue, we examined molecular evolution of a pandemic lineage, termed the GII.4_2006b, by using the full-length viral genome and VP1 sequences (n = 317) from stools collected at 20 sites in Japan between 2006 and 2011. Phylogenetic tree showed a radial diversification of the genome sequences of GII.4_2006b, suggesting a rapid genetic diversification of the GII.4_2006b population from a few ancestral variants. Impressively, amino acid sequences of the variable VP1 in given seasons remained as homogeneous as those of viral enzymes under annual increase in the nucleotide diversity in the VP1 coding region. The Hamming distances between the earliest and subsequent variants indicate strong constraints on amino acid changes even for the highly variable P2 subdomain. These results show the presence of evolutionary constraints on the VP1 protein and viral enzymes, and suggest that these proteins gain near maximal levels of fitness benefits in humans around the onset of the outbreaks. These findings have implications for our understanding of molecular evolution, mechanisms of the periodic shifts in the pandemic NoV GII.4 strains, and control of the NoV GII.4 pandemic strain. PMID:28348551

  7. Novel norovirus recombinants and of GII.4 sub-lineages associated with outbreaks between 2006 and 2010 in Belgium

    PubMed Central

    2011-01-01

    Background Noroviruses (NoVs) are an important cause of acute gastroenteritis in humans worldwide. To gain insight into the epidemiologic patterns of NoV outbreaks and to determine the genetic variation of NoVs strains circulating in Belgium, stool samples originating from patients infected with NoVs in foodborne outbreak investigations were analysed between December 2006 and December 2010. Results NoVs were found responsible of 11.8% of all suspected foodborne outbreaks reported in the last 4 years and the number of NoV outbreaks reported increased along the years representing more than 30% of all foodborne outbreaks in 2010. Genogroup II outbreaks largely predominated and represented more than 90% of all outbreaks. Phylogenetic analyses were performed with 63 NoV-positive samples for the partial polymerase (N = 45) and/or capsid gene (N = 35) sequences. For 12 samples, sequences covering the ORF1-ORF2 junction were obtained. A variety of genotypes was found among genogroups I and II; GII.4 was predominant followed in order of importance by GII.2, GII.7, GII.13, GI.4 and GI.7. In the study period, GII.4 NoVs variants 2006a, 2006b, 2007, 2008 and 2010 were identified. Moreover, phylogenetic analyses identified different recombinant NoV strains that were further characterised as intergenotype (GII.e/GII.4 2007, GII.e/GII.3 and GII.g/GII.1) and intersub-genotype (GII.4 2006b/GII.4 2007 and GII.4 2010/GII.4 2010b) recombinants. Conclusions NoVs circulating in the last 4 years in Belgium showed remarkable genetic diversity either by small-scale mutations or genetic recombination. In this period, GII.4 2006b was successfully displaced by the GII.4 2010 subtype, and previously reported epidemic GII.b recombinants seemed to have been superseded by GII.e recombinants in 2009 and GII.g recombinants in 2010. This study showed that the emergence of novel GII.4 variants together with novel GII recombinants could lead to an explosion in NoV outbreaks, likewise to what was

  8. Early Detection of Epidemic GII-4 Norovirus Strains in UK and Malawi: Role of Surveillance of Sporadic Acute Gastroenteritis in Anticipating Global Epidemics

    PubMed Central

    Callaghan, Anna; O’Brien, Sarah J.; Cunliffe, Nigel A.; Iturriza-Gómara, Miren

    2016-01-01

    Noroviruses are endemic in the human population, and are recognised as a leading cause of acute gastroenteritis worldwide. Although they are a highly diverse group of viruses, genogroup-II genotype-4 (GII-4) noroviruses are the most frequently identified strains worldwide. The predominance of GII-4 norovirus strains is driven by the periodic emergence of antigenic variants capable of evading herd protection. The global molecular epidemiology of emerging GII-4 strains is largely based on data from outbreak surveillance programmes, but the epidemiology of GII-4 strains among sporadic or community cases is far less well studied. To understand the distribution of GII-4 norovirus strains associated with gastroenteritis in the wider population, we characterised the GII-4 norovirus strains detected during studies of sporadic cases of infectious gastroenteritis collected in the UK and Malawi between 1993 and 2009. Our data shows that GII-4 norovirus strains that have emerged as strains of global epidemic importance have circulated in the community up to 18 years before their recognition as pandemic strains associated with increases in outbreaks. These data may suggest that more comprehensive surveillance programmes that incorporate strains associated with sporadic cases may provide a way for early detection of emerging strains with pandemic potential. This may be of particular relevance as vaccines become available. PMID:27115152

  9. Destruction of the Capsid and Genome of GII.4 Human Norovirus Occurs during Exposure to Metal Alloys Containing Copper

    PubMed Central

    Manuel, C. S.; Moore, M. D.

    2015-01-01

    Human norovirus (HuNoV) represents a significant public health burden worldwide and can be environmentally transmitted. Copper surfaces have been shown to inactivate the cultivable surrogate murine norovirus, but no such data exist for HuNoV. The purpose of this study was to characterize the destruction of GII.4 HuNoV and virus-like particles (VLPs) during exposure to copper alloy surfaces. Fecal suspensions positive for a GII.4 HuNoV outbreak strain or GII.4 VLPs were exposed to copper alloys or stainless steel for 0 to 240 min and recovered by elution. HuNoV genome integrity was assessed by reverse transcription-quantitative PCR (RT-qPCR) (without RNase treatment), and capsid integrity was assessed by RT-qPCR (with RNase treatment), transmission electron microscopy (TEM), SDS-PAGE/Western blot analysis, and a histo-blood group antigen (HBGA) binding assay. Exposure of fecal suspensions to pure copper for 60 min reduced the GII.4 HuNoV RNA copy number by ∼3 log10 units when analyzed by RT-qPCR without RNase treatment and by 4 log10 units when a prior RNase treatment was used. The rate of reduction of the HuNoV RNA copy number was approximately proportional to the percentage of copper in each alloy. Exposure of GII.4 HuNoV VLPs to pure-copper surfaces resulted in noticeable aggregation and destruction within 240 min, an 80% reduction in the VP1 major capsid protein band intensity in 15 min, and a near-complete loss of HBGA receptor binding within 8 min. In all experiments, HuNoV remained stable on stainless steel. These results suggest that copper surfaces destroy HuNoV and may be useful in preventing environmental transmission of the virus in at-risk settings. PMID:25979897

  10. Destruction of the Capsid and Genome of GII.4 Human Norovirus Occurs during Exposure to Metal Alloys Containing Copper.

    PubMed

    Manuel, C S; Moore, M D; Jaykus, L A

    2015-08-01

    Human norovirus (HuNoV) represents a significant public health burden worldwide and can be environmentally transmitted. Copper surfaces have been shown to inactivate the cultivable surrogate murine norovirus, but no such data exist for HuNoV. The purpose of this study was to characterize the destruction of GII.4 HuNoV and virus-like particles (VLPs) during exposure to copper alloy surfaces. Fecal suspensions positive for a GII.4 HuNoV outbreak strain or GII.4 VLPs were exposed to copper alloys or stainless steel for 0 to 240 min and recovered by elution. HuNoV genome integrity was assessed by reverse transcription-quantitative PCR (RT-qPCR) (without RNase treatment), and capsid integrity was assessed by RT-qPCR (with RNase treatment), transmission electron microscopy (TEM), SDS-PAGE/Western blot analysis, and a histo-blood group antigen (HBGA) binding assay. Exposure of fecal suspensions to pure copper for 60 min reduced the GII.4 HuNoV RNA copy number by ∼3 log10 units when analyzed by RT-qPCR without RNase treatment and by 4 log10 units when a prior RNase treatment was used. The rate of reduction of the HuNoV RNA copy number was approximately proportional to the percentage of copper in each alloy. Exposure of GII.4 HuNoV VLPs to pure-copper surfaces resulted in noticeable aggregation and destruction within 240 min, an 80% reduction in the VP1 major capsid protein band intensity in 15 min, and a near-complete loss of HBGA receptor binding within 8 min. In all experiments, HuNoV remained stable on stainless steel. These results suggest that copper surfaces destroy HuNoV and may be useful in preventing environmental transmission of the virus in at-risk settings.

  11. Median infectious dose of human norovirus GII.4 in gnotobiotic pigs is decreased by simvastatin treatment and increased by age

    PubMed Central

    Bui, Tammy; Kocher, Jacob; Li, Yanru; Wen, Ke; Li, Guohua; Liu, Fangning; Yang, Xingdong; LeRoith, Tanya; Tan, Ming; Xia, Ming; Zhong, Weiming; Jiang, Xi

    2013-01-01

    Human noroviruses (NoVs), a major cause of viral gastroenteritis, are difficult to study due to the lack of a cell-culture and a small-animal model. Pigs share with humans the types A and H histo-blood group antigens on the intestinal epithelium and have been suggested as a potential model for studies of NoV pathogenesis, immunity and vaccines. In this study, the effects of age and a cholesterol-lowering drug, simvastatin, on the susceptibility of pigs to NoV infection were evaluated. The median infectious dose (ID50) of a genogroup II, genotype 4 (GII.4) 2006b variant was determined. The ID50 in neonatal (4–5 days of age) pigs was ≤2.74×103 viral RNA copies. In older pigs (33–34 days of age), the ID50 was 6.43×104 but decreased to <2.74×103 in simvastatin-fed older pigs. Evidence of NoV infection was obtained by increased virus load in the intestinal contents, cytopathological changes in the small intestine, including irregular microvilli, necrosis and apoptosis, and detection of viral antigen in the tip of villi in duodenum. This GII.4 variant was isolated in 2008 from a patient from whom a large volume of stool was collected. GII.4 NoVs are continuously subjected to selective pressure by human immunity, and antigenically different GII.4 NoV variants emerge every 1–2 years. The determination of the ID50 of this challenge virus is valuable for evaluation of protection against different GII.4 variants conferred by NoV vaccines in concurrence with other GII.4 variants in the gnotobiotic pig model. PMID:23804568

  12. Resilience of norovirus GII.4 to freezing and thawing: implications for virus infectivity.

    PubMed

    Richards, Gary P; Watson, Michael A; Meade, Gloria K; Hovan, Gregory L; Kingsley, David H

    2012-12-01

    Genogroup II.4 norovirus (NoV) remains the predominant NoV strain in food- and water-borne outbreaks. Capsid integrity as well as viral RNA persistence were determined for GII.4 NoV by real-time RT-PCR after 1-14 freeze/thaw (F/T) cycles (-80 °C/+22 °C) or after -80 °C storage for up to 120 days. In both cases, capsid integrity and viral RNA titers remained stable. RNase was exogenously added after 1-14 F/T cycles, but did not alter the amount of genomic NoV RNA detected, indicating that capsids remained intact. Presumptive NoV infectivity was evaluated in functional studies by a porcine gastric mucin binding assay. Viruses frozen and thawed up to 14× bound similarly to porcine mucin, suggesting no reduction in virus infectivity. Overall, this study shows that a) NoV particles retain their integrity for at least 14 F/T cycles, b) long-term (120 day) frozen storage does not decrease NoV RNA titers, and c) capsid binding to receptor-like glycoprotein moieties remains unaltered after 14 F/T cycles. This work indicates that freezing and thawing of foods or beverages would not be a practical processing intervention to reduce NoV contamination. Likewise, repeated freezing and thawing, as might be encountered during winter months, is not expected to inactivate NoV in the environment. Results do show that laboratory samples destined for molecular biological analyses or for use as positive controls may be repeatedly frozen and thawed without any anticipated reduction in NoV RNA titers. This study documents the cryostability of NoV capsids and RNA to freezing and thawing and to the possible retention of virus infectivity.

  13. Norovirus diversity in children with gastroenteritis in South Africa from 2009 to 2013: GII.4 variants and recombinant strains predominate.

    PubMed

    Mans, J; Murray, T Y; Nadan, S; Netshikweta, R; Page, N A; Taylor, M B

    2016-04-01

    From 2009 to 2013 the diversity of noroviruses (NoVs) in children (⩽5 years) hospitalized with gastroenteritis in South Africa was investigated. NoVs were genotyped based on nucleotide sequence analyses of partial RNA-dependent RNA polymerase (RdRp) and capsid genes. Seventeen RdRp genotypes (GI.P2, GI.P3, GI.P6, GI.P7, GI.P not assigned (NA), GI.Pb, GI.Pf, GII.P2, GII.P4, GII.P7, GII.P13, GII.P16, GII.P21, GII.Pc, GII.Pe, GII.Pg, GII.PNA) and 20 capsid genotypes (GI.1, GI.2, GI.3, GI.5, GI.6, GI.7, GI.NA, GII.1, GII.2, GII.3, GII.4, GII.6, GII.7, GII.10, GII.12, GII.13, GII.14, GII.16, GII.17, GII.21) were identified. The combined RdRp/capsid genotype was determined for 275 GII strains. Fifteen confirmed recombinant NoV strains circulated during the study period. NoV GII.P4/GII.4 (47%) and GII.Pe/GII.4 (18%) predominated, followed by GII.PNA/GII.3 (10%) and GII.P21/GII.3 (7%). Other prevalent strains included GII.Pg/GII.12 (6%) and GII.Pg/GII.1 (3%). Two novel recombinants, GII.Pg/GII.2 and GII.Pg/GII.10 were identified. In 2013 the replacement of GII.4 New Orleans 2009 and GII.P21/GII.3, which predominated during the early part of the study, with GII.4 Sydney 2012 and GII.PNA/GII.3 was observed. This study presents the most comprehensive recent data on NoV diversity in Africa.

  14. Emergence of new recombinant noroviruses GII.p16-GII.4 and GII.p16-GII.2, France, winter 2016 to 2017.

    PubMed

    Bidalot, Maxime; Théry, Lucie; Kaplon, Jérôme; De Rougemont, Alexis; Ambert-Balay, Katia

    2017-04-13

    An early increase in outbreaks of norovirus gastroenteritis characterised at the French National Reference Centre occurred this winter season. They were concurrent with an unusual pattern of circulating strains, with three predominant genotypes: the re-emergent variant GII.P4 2009-GII.4 2012 found in 28% of norovirus outbreaks and two new emergent recombinant strains GII.P16-GII.4 2012 and GII.P16-GII.2 never before observed in France, found in 24% and 14% of norovirus outbreaks, respectively. This article is copyright of The Authors, 2017.

  15. Genetic and Epidemiologic Trends of Norovirus Outbreaks in the United States from 2013 to 2016 Demonstrated Emergence of Novel GII.4 Recombinant Viruses

    PubMed Central

    Cannon, Jennifer L.; Barclay, Leslie; Collins, Nikail R.; Wikswo, Mary E.; Castro, Christina J.; Magaña, Laura Cristal; Gregoricus, Nicole; Marine, Rachel L.; Chhabra, Preeti

    2017-01-01

    ABSTRACT Noroviruses are the most frequent cause of epidemic acute gastroenteritis in the United States. Between September 2013 and August 2016, 2,715 genotyped norovirus outbreaks were submitted to CaliciNet. GII.4 Sydney viruses caused 58% of the outbreaks during these years. A GII.4 Sydney virus with a novel GII.P16 polymerase emerged in November 2015, causing 60% of all GII.4 outbreaks in the 2015-2016 season. Several genotypes detected were associated with more than one polymerase type, including GI.3, GII.2, GII.3, GII.4 Sydney, GII.13, and GII.17, four of which harbored GII.P16 polymerases. GII.P16 polymerase sequences associated with GII.2 and GII.4 Sydney viruses were nearly identical, suggesting common ancestry. Other common genotypes, each causing 5 to 17% of outbreaks in a season, included GI.3, GI.5, GII.2, GII.3, GII.6, GII.13, and GII.17 Kawasaki 308. Acquisition of alternative RNA polymerases by recombination is an important mechanism for norovirus evolution and a phenomenon that was shown to occur more frequently than previously recognized in the United States. Continued molecular surveillance of noroviruses, including typing of both polymerase and capsid genes, is important for monitoring emerging strains in our continued efforts to reduce the overall burden of norovirus disease. PMID:28490488

  16. Genotypes, Recombinant Forms, and Variants of Norovirus GII.4 in Gipuzkoa (Basque Country, Spain), 2009–2012

    PubMed Central

    Arana, Ainara; Cilla, Gustavo; Montes, Milagrosa; Gomariz, María; Pérez-Trallero, Emilio

    2014-01-01

    Background Noroviruses (NoVs) are genetically diverse, with genogroup II—and within it—genotype 4 (GII.4) being the most prevalent cause of acute gastroenteritis worldwide. The aim of this study was to characterize genogroup II NoV causing acute gastroenteritis in the Basque Country (northern Spain) from 2009–2012. Methods The presence of NoV RNA was investigated by reverse transcriptase-polymerase chain reaction (RT-PCR) in stool specimens from children younger than 15 years old with community-acquired acute gastroenteritis, and from hospitalized adults or elderly residents of nursing homes with acute gastroenteritis. For genotyping, the open reading frames ORF1 (encoding the polymerase) and ORF2 (encoding the major capsid protein) were partially amplified and sequenced. Recombinant strains were confirmed by PCR of the ORF1/ORF2 junction region. Results NoV was detected in 16.0% (453/2826) of acute gastroenteritis episodes in children younger than 2 years, 9.9% (139/1407) in children from 2 to 14 years, and 35.8% (122/341) in adults. Of 317 NoVs characterized, 313 were genogroup II and four were genogroup I. The GII.4 variants Den Haag-2006b and New Orleans-2009 predominated in 2009 and 2010–2011, respectively. In 2012, the New Orleans-2009 variant was partially replaced by the Sydney-2012 variant (GII.Pe/GII.4) and New Orleans-2009/Sydney-2012 recombinant strains. The predominant capsid genotype in all age groups was GII.4, which was the only genotype detected in outbreaks. The second most frequent genotype was GII.3 (including the recently described recombination GII.P16/GII.3), which was detected almost exclusively in children. Conclusion Nine different genotypes of NoV genogroup II were detected; among these, intergenotype recombinant strains represented an important part, highlighting the role of recombination in the evolution of NoVs. Detection of new NoV strains, not only GII.4 strains, shortly after their first detection in other parts of the world

  17. Recognition of Histo-Blood Group Antigen-Like Carbohydrates in Lettuce by Human GII.4 Norovirus

    PubMed Central

    Gao, Xiang; Esseili, Malak A.; Lu, Zhongyan; Saif, Linda J.

    2016-01-01

    ABSTRACT Human norovirus (HuNoV) genogroup II genotype 4 (GII.4) strains account for about 80% of the gastroenteritis outbreaks in the United States. Contaminated food is a major transmission vehicle for this virus. In humans, pigs, and oysters, histo-blood group antigens (HBGAs) act as attachment factors for HuNoVs. In lettuce, although the virus-like particles (VLPs) of a GII.4 HuNoV were found to bind to cell wall carbohydrates, the exact binding site has not been investigated. Here, we show the presence of HBGA-like carbohydrates in the cell wall of lettuce. The digestion of lettuce leaves with cell wall-degrading enzymes exposed more binding sites and significantly increased the level of binding of GII.4 HuNoV VLPs. Competition assays showed that both the HBGA monoclonal antibody, recognizing the H type, and plant lectins, recognizing α-l-fucose in the H type, effectively inhibited VLP binding to lettuce tissues. Lettuce cell wall components were isolated and their NoV VLP binding characteristics were tested by enzyme-linked immunosorbent assays. The binding was inhibited by pretreatment of the lettuce cell wall materials with α-1,2-fucosidase. Collectively, our results indicate that H-type HBGA-like carbohydrates exist in lettuce tissues and that GII.4 HuNoV VLPs can bind the exposed fucose moiety, possibly in the hemicellulose component of the cell wall. IMPORTANCE Salad crops and fruits are increasingly recognized as vehicles for human norovirus (HuNoV) transmission. A recent study showed that HuNoVs specifically bind to the carbohydrates of the lettuce cell wall. Histo-blood group antigens (HBGAs) are carbohydrates and are known as the attachment factors for HuNoV infection in humans. In this study, we show the presence of HBGA-like carbohydrates in lettuce, to which HuNoVs specifically bind. These results suggest that specifically bound HuNoVs cannot be removed by simple washing, which may allow viral transmission to consumers. Our findings provide new

  18. Recognition of Histo-Blood Group Antigen-Like Carbohydrates in Lettuce by Human GII.4 Norovirus.

    PubMed

    Gao, Xiang; Esseili, Malak A; Lu, Zhongyan; Saif, Linda J; Wang, Qiuhong

    2016-05-15

    Human norovirus (HuNoV) genogroup II genotype 4 (GII.4) strains account for about 80% of the gastroenteritis outbreaks in the United States. Contaminated food is a major transmission vehicle for this virus. In humans, pigs, and oysters, histo-blood group antigens (HBGAs) act as attachment factors for HuNoVs. In lettuce, although the virus-like particles (VLPs) of a GII.4 HuNoV were found to bind to cell wall carbohydrates, the exact binding site has not been investigated. Here, we show the presence of HBGA-like carbohydrates in the cell wall of lettuce. The digestion of lettuce leaves with cell wall-degrading enzymes exposed more binding sites and significantly increased the level of binding of GII.4 HuNoV VLPs. Competition assays showed that both the HBGA monoclonal antibody, recognizing the H type, and plant lectins, recognizing α-l-fucose in the H type, effectively inhibited VLP binding to lettuce tissues. Lettuce cell wall components were isolated and their NoV VLP binding characteristics were tested by enzyme-linked immunosorbent assays. The binding was inhibited by pretreatment of the lettuce cell wall materials with α-1,2-fucosidase. Collectively, our results indicate that H-type HBGA-like carbohydrates exist in lettuce tissues and that GII.4 HuNoV VLPs can bind the exposed fucose moiety, possibly in the hemicellulose component of the cell wall. Salad crops and fruits are increasingly recognized as vehicles for human norovirus (HuNoV) transmission. A recent study showed that HuNoVs specifically bind to the carbohydrates of the lettuce cell wall. Histo-blood group antigens (HBGAs) are carbohydrates and are known as the attachment factors for HuNoV infection in humans. In this study, we show the presence of HBGA-like carbohydrates in lettuce, to which HuNoVs specifically bind. These results suggest that specifically bound HuNoVs cannot be removed by simple washing, which may allow viral transmission to consumers. Our findings provide new information needed

  19. Emergence of Norovirus GII.4 variants in acute gastroenteritis outbreaks in South Korea between 2006 and 2013.

    PubMed

    Cho, Han-Gil; Park, Po-Hyun; Lee, Sung-Geun; Kim, Ju-Eun; Kim, Kyung-A; Lee, Hyeun-Kyong; Park, Eun-Mi; Park, Myong-Ki; Jung, Sun-Young; Lee, Deog-Yong; Yoon, Mi-Hye; Lee, Jong-Bok; Paik, Soon-Young

    2015-11-01

    New emerging strains of noroviruses (NoVs) often increase acute gastroenteritis (AGE) outbreaks worldwide. We analyzed the epidemiological features and genotypic patterns of NoVs in AGE outbreaks. To elucidate the public health impact of NoVs during AGE outbreaks in South Korea, a molecular and epidemiological investigation was performed with 318 AGE outbreaks reported from the Gyeonggi province of South Korea during the period from 2006 to 2013. NoVs were associated with 102 (32.1%) of the AGE outbreaks. Epidemiological data revealed that the majority of NoV outbreaks were in the student group (47.1%), and the majority of AGE patients were identified in schools (68.8%). NoV genogroup (G) II strains were associated with 94 (92.2%) of the NoV outbreaks, and GII.4 strains were predominantly associated with 57.6% (n=49) of NoV GII outbreaks. Four GII.4 variants (2006b, 2007, 2009 and 2012 variants) emerged and showed different contributions to NoV outbreak activity. The 2006b variant was predominantly associated with NoV outbreaks during the early years of the study period, and was subsequently displaced by the New Orleans 2009 variant, and most recently by the Sydney 2012 variant. In addition, the GII.2, GII.14, and GII.17 strains have recently been often associated with NoV AGE outbreaks. The emergence of new NoV GII.4 variants significantly affected the NoV outbreak activity in South Korea during the period from 2006 to 2013. The surveillance for new emerging strains affecting NoV outbreak activity should be intensified to develop an adequate policy to prevent further NoV outbreaks. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Emergence of a New Norovirus GII.4 Variant and Changes in the Historical Biennial Pattern of Norovirus Outbreak Activity in Alberta, Canada, from 2008 to 2013

    PubMed Central

    Hasing, Maria E.; Preiksaitis, Jutta K.; Tellier, Raymond; Honish, Lance; Senthilselvan, Ambikaipakan; Pang, Xiaoli L.

    2013-01-01

    The public health impact of the emergence of new norovirus (NoV) strains is uncertain. A biennial pattern of alternating quiescent and epidemic levels of NoV outbreak activity associated with the emergence of new GII.4 variants was observed in Alberta, Canada, between July 2000 and June 2008. In this study, NoV genogroup I (GI) and GII strains isolated from 710 outbreak specimens in Alberta between July 2008 and January 2013 were characterized to update historical data. The seasonality and annual variation in NoV outbreak burden were analyzed over a 10-year period (July 2002 to June 2012). We found that GII.4-2006b had persisted as the predominant variant over three observation periods (July 2006 to June 2009) during which the biennial NoV outbreak pattern continued. The emergence of GII.4-2010 (winter 2009) was not associated with increased outbreak activity, and outbreak activity between July 2009 and June 2012 when GII.4-2010 predominated (67.5 to 97.7%) did not follow a biennial pattern. GII.4-2012 first emerged in Alberta in September 2011 and became predominant in observation period July 2012 to June 2013. NoV GI, relatively rare in past years, had a higher activity level (37.3%) as represented by GI.6 and GI.7 in the winter of 2012 to 2013. A higher proportion of GI outbreaks occurred in non-health care facility settings compared to GII. Our study suggests that factors other than new variants emergence contribute to the levels of NoV outbreak activity in Alberta. PMID:23637302

  1. Norovirus GII.4 variant 2006b caused epidemics of acute gastroenteritis in Australia during 2007 and 2008.

    PubMed

    Eden, John-Sebastian; Bull, Rowena A; Tu, Elise; McIver, Christopher J; Lyon, Michael J; Marshall, John A; Smith, David W; Musto, Jennie; Rawlinson, William D; White, Peter A

    2010-12-01

    Over the last decade, four epidemics of norovirus-associated gastroenteritis have been reported in Australia. These epidemics were characterized by numerous outbreaks in institutional settings such as hospitals and nursing homes, as well as increases in requests for NoV testing in diagnostic centers. During 2007 and 2008, widespread outbreaks of acute gastroenteritis were once again seen across Australia, peaking during the winter months. The primary objective of this study was to characterize two winter epidemics of NoV-associated gastroenteritis in 2007 and 2008 in Australia. Following this, we aimed to determine if these epidemics were caused by a new GII.4 variant or a previously circulating NoV strain. NoV-positive fecal samples (n=219) were collected over a 2-year period, December 2006 to December 2008, from cases of acute gastroenteritis in Australia. NoV RNA was amplified from these samples using a nested RT-PCR approach targeting the 5' end of the capsid gene, termed region C. Further, characterization was performed by sequence analysis of the RdRp and capsid genes and recombination was identified using SimPlot. From 2004 to 2008, peaks in the numbers of NoV-positive EIA tests from the Prince of Wales Hospital Laboratory correlated with the overall number of gastroenteritis outbreaks reported to NSW Health, thereby supporting recent studies showing that NoV is the major cause of outbreak gastroenteritis. The predominant NoV GII variant identified during the 2007-2008 period was the GII.4 pandemic variant, 2006b (71.51%, 128/179), which replaced the 2006a variant identified in the previous Australian epidemic of 2006. Four novel GII variants were also identified including the three GII.4 variants: NoV 2008, NoV Osaka 2007 and NoV Cairo 2007, and one novel recombinant NoV designated GII.e/GII.12. The increase in acute gastroenteritis outbreaks in 2007 and 2008 were associated with the spread of the NoV GII.4 variant 2006b. Copyright © 2010 Elsevier B.V. All

  2. Multiple Antigenic Sites Are Involved in Blocking the Interaction of GII.4 Norovirus Capsid with ABH Histo-Blood Group Antigens

    PubMed Central

    Parra, Gabriel I.; Abente, Eugenio J.; Sandoval-Jaime, Carlos; Sosnovtsev, Stanislav V.; Bok, Karin

    2012-01-01

    Noroviruses are major etiological agents of acute viral gastroenteritis. In 2002, a GII.4 variant (Farmington Hills cluster) spread so rapidly in the human population that it predominated worldwide and displaced previous GII.4 strains. We developed and characterized a panel of six monoclonal antibodies (MAbs) directed against the capsid protein of a Farmington Hills-like GII.4 norovirus strain that was associated with a large hospital outbreak in Maryland in 2004. The six MAbs reacted with high titers against homologous virus-like particles (VLPs) by enzyme-linked immunoassay but did not react with denatured capsid protein in immunoblots. The expression and self-assembly of newly developed genogroup I/II chimeric VLPs showed that five MAbs bound to the GII.4 protruding (P) domain of the capsid protein, while one recognized the GII.4 shell (S) domain. Cross-competition assays and mutational analyses showed evidence for at least three distinct antigenic sites in the P domain and one in the S domain. MAbs that mapped to the P domain but not the S domain were able to block the interaction of VLPs with ABH histo-blood group antigens (HBGA), suggesting that multiple antigenic sites of the P domain are involved in HBGA blocking. Further analysis showed that two MAbs mapped to regions of the capsid that had been associated with the emergence of new GII.4 variants. Taken together, our data map antibody and HBGA carbohydrate binding to proximal regions of the norovirus capsid, showing that evolutionary pressures on the norovirus capsid protein may affect both antigenic and carbohydrate recognition phenotypes. PMID:22532688

  3. Bacterial surface-displayed GII.4 human norovirus capsid proteins bound to surface of Romaine lettuce through HBGA-like molecules

    USDA-ARS?s Scientific Manuscript database

    Human Noroviruses (HuNoVs) are the main cause of nonbacterial gastroenteritis. Contaminated produce is a main vehicle for dissemination of HuNoVs. In this study, we used an ice nucleation protein (INP) mediated surface display system to present the protruding domain of GII.4 HuNoV capsid protein (G...

  4. Gastroenteritis Outbreaks Associated with the Emergence of the New GII.4 Sydney Norovirus Variant during the Epidemic of 2012/13 in Shenzhen City, China

    PubMed Central

    Chen, Kena; Zhang, Hailong; Yang, Hong; Zhuo, Fei; Zhao, Dejian; Zeng, Huatang; Yao, Xiangjie; Zhang, Zhen; Chen, Long; Zhou, Yuanping; Duan, Zhao-jun

    2016-01-01

    Noroviruses (NoVs) are the leading cause of gastroenteritis outbreaks in humans worldwide. Since late 2012, a new GII.4 variant Sydney 2012 has caused a significant increase in NoV epidemics in several countries. From November of 2012 to January of 2013, three gastroenteritis outbreaks occurred in two social welfare homes (Outbreaks A and B) and a factory (Outbreak C) in Shenzhen city of China. Feces and swabs were collected for laboratory tests for causative agents. While no bacterial pathogen was identified, all three outbreaks were caused by NoVs with detection rates of 26.2% (16/61) at Outbreak A, 35.2% (38/108) at Outbreak B), and 59.3% (16/27) at Outbreaks C. For Outbreak B, 25 of the 29 symptomatic individuals (86.2%) and 13 of the 79 asymptomatic individuals (16.5%) were found NoV-positive. For Outbreak C, an asymptomatic food handler was NoV-positive. All thirteen NoV sequences from the three outbreaks were classified into genogroup II and genotype 4 (GII.4), which we identified to be the GII.4 Sydney 2012 variant. The genome of two isolates from Outbreaks A and B were recombinant with the opening reading frame (ORF) 1 of GII.4 Osaka 2007 and ORF2 and 3 of the GII.4 New Orleans. Our study indicated that the GII.4 Sydney 2012 variant emerged and caused the outbreaks in China. PMID:27829005

  5. Binding of Human GII.4 Norovirus Virus-Like Particles to Carbohydrates of Romaine Lettuce Leaf Cell Wall Materials

    PubMed Central

    Esseili, Malak A.

    2012-01-01

    Norovirus (NoV) genogroup II genotype 4 (GII.4) strains are the dominant cause of the majority of food-borne outbreaks, including those that involve leafy greens, such as lettuce. Since human NoVs use carbohydrates of histo-blood group antigens as receptors/coreceptors, we examined the role of carbohydrates in the attachment of NoV to lettuce leaves by using virus-like particles (VLPs) of a human NoV/GII.4 strain. Immunofluorescence analysis showed that the VLPs attached to the leaf surface, especially to cut edges, stomata, and along minor veins. Binding was quantified using enzyme-linked immunosorbent assay (ELISA) performed on cell wall materials (CWM) from innermost younger leaves and outermost lamina of older leaves. The binding to CWM of older leaves was significantly (P < 0.05) higher (1.5- to 2-fold) than that to CWM of younger leaves. Disrupting the carbohydrates of CWM or porcine gastric mucin (PGM) (a carbohydrate control) using 100 mM sodium periodate (NaIO4) significantly decreased the binding an average of 17% in younger leaves, 43% in older leaves, and 92% for PGM. In addition, lectins recognizing GalNAc, GlcNAc, and sialic acid at 100 μg/ml significantly decreased the binding an average of 41%, 33%, and 20% on CWM of older leaves but had no effect on younger leaves. Lectins recognizing α-d-Gal, α-d-Man/α-d-Glc, and α-l-Fuc showed significant inhibition on CWM of older leaves as well as that of younger leaves. All lectins, except for the lectin recognizing α-d-Gal, significantly inhibited NoV VLP binding to PGM. Collectively, our results indicate that NoV VLPs bind to lettuce CWM by utilizing multiple carbohydrate moieties. This binding may enhance virus persistence on the leaf surface and prevent effective decontamination. PMID:22138991

  6. Elucidation of strain-specific interaction of a GII-4 norovirus with HBGA receptors by site-directed mutagenesis study

    SciTech Connect

    Tan Ming |; Xia Ming; Cao Sheng; Huang Pengwei; Farkas, Tibor |; Meller, Jarek |; Hegde, Rashmi S. |; Li Xuemei; Rao Zihe; Jiang Xi |

    2008-09-30

    Noroviruses interact with histo-blood group antigen (HBGA) receptors in a strain-specific manner probably detecting subtle structural differences in the carbohydrate receptors. The specific recognition of types A and B antigens by various norovirus strains is a typical example. The only difference between the types A and B antigens is the acetamide linked to the terminal galactose of the A but not to the B antigen. The crystal structure of the P dimer of a GII-4 norovirus (VA387) bound to types A and B trisaccharides has elucidated the A/B binding site on the capsid but did not explain the binding specificity of the two antigens. In this study, using site-directed mutagenesis, we have identified three residues on the VA387 capsid that are sterically close to the acetamide and are required for binding to A but not B antigens, indicating that the acetamide determines the binding specificity between the A and B antigens. Further mutational analysis showed that a nearby open cavity may also be involved in binding specificity to HBGAs. In addition, a systematic mutational analysis of residues in and around the binding interface has identified a group of amino acids that are required for binding but do not have direct contact with the carbohydrate antigens, implying that these residues may be involved in the structural integrity of the receptor binding interface. Taken together, our study provides new insights into the carbohydrate/capsid interactions which are a valuable complement to the atomic structures in understanding the virus/host interaction and in the future design of antiviral agents.

  7. The G428A nonsense mutation in FUT2 provides strong but not absolute protection against symptomatic GII.4 Norovirus infection.

    PubMed

    Carlsson, Beatrice; Kindberg, Elin; Buesa, Javier; Rydell, Gustaf E; Lidón, Marta Fos; Montava, Rebeca; Abu Mallouh, Reem; Grahn, Ammi; Rodríguez-Díaz, Jesús; Bellido, Juan; Arnedo, Alberto; Larson, Göran; Svensson, Lennart

    2009-01-01

    In November 2004, 116 individuals in an elderly nursing home in El Grao de Castellón, Spain were symptomatically infected with genogroup II.4 (GII.4) norovirus. The global attack rate was 54.2%. Genotyping of 34 symptomatic individuals regarding the FUT2 gene revealed that one patient was, surprisingly, a non-secretor, hence indicating secretor-independent infection. Lewis genotyping revealed that Lewis-positive and negative individuals were susceptible to symptomatic norovirus infection indicating that Lewis status did not predict susceptibility. Saliva based ELISA assays were used to determine binding of the outbreak virus to saliva samples. Saliva from a secretor-negative individual bound the authentic outbreak GII.4 Valencia/2004/Es virus, but did not in contrast to secretor-positive saliva bind VLP of other strains including the GII.4 Dijon strain. Amino acid comparison of antigenic A and B sites located on the external loops of the P2 domain revealed distinct differences between the Valencia/2004/Es and Dijon strains. All three aa in each antigenic site as well as 10/11 recently identified evolutionary hot spots, were unique in the Valencia/2004/Es strain compared to the Dijon strain. To the best of our knowledge, this is the first example of symptomatic GII.4 norovirus infection of a Le(a+b-) individual homozygous for the G428A nonsense mutation in FUT2. Taken together, our study provides new insights into the host genetic susceptibility to norovirus infections and evolution of the globally dominating GII.4 viruses.

  8. The G428A Nonsense Mutation in FUT2 Provides Strong but Not Absolute Protection against Symptomatic GII.4 Norovirus Infection

    PubMed Central

    Buesa, Javier; Rydell, Gustaf E.; Lidón, Marta Fos; Montava, Rebeca; Mallouh, Reem Abu; Grahn, Ammi; Rodríguez-Díaz, Jesús; Bellido, Juan; Arnedo, Alberto; Larson, Göran; Svensson, Lennart

    2009-01-01

    In November 2004, 116 individuals in an elderly nursing home in El Grao de Castellón, Spain were symptomatically infected with genogroup II.4 (GII.4) norovirus. The global attack rate was 54.2%. Genotyping of 34 symptomatic individuals regarding the FUT2 gene revealed that one patient was, surprisingly, a non-secretor, hence indicating secretor-independent infection. Lewis genotyping revealed that Lewis-positive and negative individuals were susceptible to symptomatic norovirus infection indicating that Lewis status did not predict susceptibility. Saliva based ELISA assays were used to determine binding of the outbreak virus to saliva samples. Saliva from a secretor-negative individual bound the authentic outbreak GII.4 Valencia/2004/Es virus, but did not in contrast to secretor-positive saliva bind VLP of other strains including the GII.4 Dijon strain. Amino acid comparison of antigenic A and B sites located on the external loops of the P2 domain revealed distinct differences between the Valencia/2004/Es and Dijon strains. All three aa in each antigenic site as well as 10/11 recently identified evolutionary hot spots, were unique in the Valencia/2004/Es strain compared to the Dijon strain. To the best of our knowledge, this is the first example of symptomatic GII.4 norovirus infection of a Lea+b− individual homozygous for the G428A nonsense mutation in FUT2. Taken together, our study provides new insights into the host genetic susceptibility to norovirus infections and evolution of the globally dominating GII.4 viruses. PMID:19440360

  9. Antibodies against Lewis antigens inhibit the binding of human norovirus GII.4 virus-like particles to saliva but not to intestinal Caco-2 cells.

    PubMed

    Carmona-Vicente, Noelia; Allen, David J; Rodríguez-Díaz, Jesús; Iturriza-Gómara, Miren; Buesa, Javier

    2016-05-21

    Human noroviruses (NoVs) are the main cause of gastroenteritis worldwide. The most commonly detected NoV strains belong to the genetically diverse GII.4 genotype, with new pandemic variants emerging periodically. Despite extensive efforts, NoV investigation has been hampered by the lack of an effective in vitro cell culture system. However, NoV-derived recombinant virus-like particles (VLPs) resembling empty capsids are good surrogates for analysing NoV antigenicity and virus-ligand interactions. NoV VLPs have been reported to bind to histo-blood group antigens (HBGAs). We have analysed the ability of NoV VLPs derived from GI.1 genotype and from three GII.4 genotype variants, GII.4-1999, GII.4-2004 and GII.4-2006b, to bind to porcine gastric mucin (PGM), human saliva and differentiated human intestinal Caco-2 cells (D-Caco-2 cells). Distinct patterns of saliva binding with the NoV GII.4 variant VLPs were observed, although they bound to D-Caco-2 cells independently of the expression of HBGAs. Monoclonal antibodies against Lewis antigens were able to block the binding of NoV VLPs to saliva, but not to D-Caco-2 cells. Blocking HBGAs on the surface of D-Caco-2 cells with specific monoclonal antibodies did not affect NoV VLP binding to cellular membranes. Co-localisation of Lewis y (Le(y)) and H-type 2 antigens with NoV VLPs was not observed by immunofluorescence assays. Although the binding of NoV VLPs of GII.4 genotype variants to human saliva samples occur with distinct HBGA binding patterns and can be blocked by antibodies against Lewis antigens, their attachment to D-Caco-2 cells can be mediated by other receptors, which still need further investigation.

  10. Effects of a variety of food extracts and juices on the specific binding ability of norovirus GII.4 P particles.

    PubMed

    Li, Dan; Baert, Leen; Xia, Ming; Zhong, Weiming; Jiang, Xi; Uyttendaele, Mieke

    2012-07-01

    The effects of 13 food extracts and juices, including shellfish, fruits, and vegetables, on the binding ability of human norovirus (NoV) were examined, using P particles of human NoV GII.4 as a research surrogate. The enhancements (positive values) or reductions (negative values) of NoV P particle detection (changes in optical density at 450 nm) in the presence of different food extracts and juices as compared with P particles diluted in phosphate-buffered saline were tested by saliva-binding, enzyme-linked immunosorbent assay in triplicate. In the presence of different food extracts and juices at different concentrations, an increase or decrease of the receptor-binding ability of the NoV P particles was observed. Due to a higher specific binding and thus a higher accumulation of the viral particles, oysters may be contaminated with human NoV more often than other shellfish species (mussel, hard clams, and razor clams). Cranberry and pomegranate juices were shown to reduce the specific binding ability of human NoV P particles. No such binding inhibition effects were observed for the other tested extracts of fresh produce (strawberry, blackberry, blueberry, cherry tomato, spinach, romaine lettuce) or, notably, for raspberry, which has been associated with human NoV outbreaks.

  11. Prevailing Sydney like Norovirus GII.4 VLPs induce systemic and mucosal immune responses in mice.

    PubMed

    Huo, Yuqi; Wan, Xin; Ling, Tong; Wu, Jie; Wang, Zejun; Meng, Shengli; Shen, Shuo

    2015-12-01

    The newly emerged Norovirus (NoV) Sydney 2012 strain has been sweeping all over the world, causing acute non-bacterial gastroenteritis in adults and children. Due to a lack of cell culture system, virus like particles (VLPs) has been assembled and used as vaccine candidates in preclinical and clinical studies. Expression of the major capsid protein of NoVs using recombinant baculovirus expression system in Sf9 cells leads to formation of VLPs that are morphologically and antigenically similar to true virions. In this study, VLPs were successfully produced using the VP1 of Sydney-2012-like strain and its immunogenicity was evaluated by different routes and its capability in inducing mucosal immune responses in the presence and absence of adjuvants in BALB/c mice. Administration of NoV VLPs in the presence of Al(OH)3 or monophosphoryl lipid A (MPL-A) led to high titers of VLP-specific IgG antibodies. Administration of VLPs orally in the presence of cholera toxin subunit B (CTB) didn't enhance mucosal immune response as less fecal IgA positive mice were observed when compared with those given VLPs only. Our study represents the first immunogenicity study of VLPs derived from current pandemic Sydney 2012 strain and which might have implications in the development of NoVs vaccine in china.

  12. Genetic Analysis of Norovirus GII.4 Variant Strains Detected in Outbreaks of Gastroenteritis in Yokohama, Japan, from the 2006-2007 to the 2013-2014 Seasons.

    PubMed

    Kumazaki, Makoto; Usuku, Shuzo

    2015-01-01

    Noroviruses (NoVs) are the leading cause of acute gastroenteritis, both in sporadic cases and outbreaks. Since the 1990s, the emergence of several GII.4 variants has been reported worldwide. To investigate the epidemic status of NoV, 6,724 stool samples collected from outbreaks in Yokohama, Japan, from the 2006-2007 to 2013-2014 seasons were assessed for NoVs. We genotyped one specimen from each GII outbreak and conducted a sequence analysis of the VP1 gene for several GII.4 strains. Of the 947 NoV outbreaks during our study, GII was detected in 835, and GII.4 was the predominant genotype of GII. Five different GII.4 variants, Yerseke 2006a, Den Haag 2006b (2006b), Apeldoorn 2007, New Orleans 2009, and Sydney 2012, were detected. During this study period, the most prevalent variant of GII.4 was 2006b, and in each individual season, either 2006b or Sydney 2012 was the predominant variant. Out of the 16 detected 2006b strains, 12 had some amino acid substitutions in their blockade epitope, and these substitutions were concentrated in three residues. Two of the 2006b strains detected in the 2012-2013 season had a S368E substitution, which is consistent with the amino acid residues at same site of NSW0514 (Sydney 2012 prototype). Among the 16 detected strains of Sydney 2012, a phylogenetic analysis showed that all five strains detected in Yokohama during the 2011-2012 season clustered away from the other Sydney 2012 strains that were detected in the 2012-2013 and 2013-2014 seasons. These five strains and other Sydney 2012 strains in Yokohama had a few amino acid differences in the blockade epitopes compared with NSW0514. The amino acid substitutions observed in this study provide informative data about the evolution of a novel GII.4 variant.

  13. Bacterial Surface-Displayed GII.4 Human Norovirus Capsid Proteins Bound to HBGA-Like Molecules in Romaine Lettuce.

    PubMed

    Wang, Ming; Rong, Shaofeng; Tian, Peng; Zhou, Yue; Guan, Shimin; Li, Qianqian; Wang, Dapeng

    2017-01-01

    Human Noroviruses (HuNoVs) are the main cause of non-bacterial gastroenteritis. Contaminated produce is a main vehicle for dissemination of HuNoVs. In this study, we used an ice nucleation protein mediated surface display system to present the protruding domain of GII.4 HuNoV capsid protein on bacterial surface and used it as a new strategy to explore interaction between HuNoV protein and receptor candidates from romaine lettuce. The surface-displayed HuNoV proteins were confirmed on the surface of the transformed bacteria by an immunofluorescence assay. The distribution patterns of the surface-displayed HuNoV proteins in romaine lettuce were identified through a confocal immunofluorescence assay. The surface-displayed HuNoV proteins could be found in the stomata, and the surfaces of vein and leaf of romaine lettuce. The surface-displayed HuNoV proteins could be captured by an ELISA assay utilizing extract from leaf (LE) or vein (VE). The binding of the surface-displayed HuNoV proteins to LE or VE could be competitively blocked by histo-blood group antigens from human saliva. In addition, the binding of the surface-displayed HuNoV proteins to LE or VE could also be attenuated by heat denaturation of lettuce proteins, and abolished by oxidation of lettuce carbohydrates. The results indicated that histo-blood group antigen-like molecules in LE or VE were involved in the binding of the surface-displayed HuNoV proteins to romaine lettuce. All data demonstrated that the surface-displayed HuNoV proteins could be utilized in a new and simple system for investigation of the interaction between the HuNoVs and their candidate ligands.

  14. Bacterial Surface-Displayed GII.4 Human Norovirus Capsid Proteins Bound to HBGA-Like Molecules in Romaine Lettuce

    PubMed Central

    Wang, Ming; Rong, Shaofeng; Tian, Peng; Zhou, Yue; Guan, Shimin; Li, Qianqian; Wang, Dapeng

    2017-01-01

    Human Noroviruses (HuNoVs) are the main cause of non-bacterial gastroenteritis. Contaminated produce is a main vehicle for dissemination of HuNoVs. In this study, we used an ice nucleation protein mediated surface display system to present the protruding domain of GII.4 HuNoV capsid protein on bacterial surface and used it as a new strategy to explore interaction between HuNoV protein and receptor candidates from romaine lettuce. The surface-displayed HuNoV proteins were confirmed on the surface of the transformed bacteria by an immunofluorescence assay. The distribution patterns of the surface-displayed HuNoV proteins in romaine lettuce were identified through a confocal immunofluorescence assay. The surface-displayed HuNoV proteins could be found in the stomata, and the surfaces of vein and leaf of romaine lettuce. The surface-displayed HuNoV proteins could be captured by an ELISA assay utilizing extract from leaf (LE) or vein (VE). The binding of the surface-displayed HuNoV proteins to LE or VE could be competitively blocked by histo-blood group antigens from human saliva. In addition, the binding of the surface-displayed HuNoV proteins to LE or VE could also be attenuated by heat denaturation of lettuce proteins, and abolished by oxidation of lettuce carbohydrates. The results indicated that histo-blood group antigen-like molecules in LE or VE were involved in the binding of the surface-displayed HuNoV proteins to romaine lettuce. All data demonstrated that the surface-displayed HuNoV proteins could be utilized in a new and simple system for investigation of the interaction between the HuNoVs and their candidate ligands. PMID:28265267

  15. Outbreak of gastroenteritis caused by norovirus GII.4 Sydney variant after a wedding reception at a resort/activity centre, Finland, August 2012.

    PubMed

    Polkowska, A; Rönnqvist, M; Lepistö, O; Roivainen, M; Maunula, L; Huusko, S; Toikkanen, S; Rimhanen-Finne, R

    2014-09-01

    In August 2012, an outbreak of gastroenteritis occurred among 88 persons attending a wedding reception at a resort/activity centre in Ylöjärvi, Finland. Of 39 interviewed guests, 23 met the case definition. Two persons were hospitalized. Epidemiological, laboratory and environmental investigations were conducted to characterize the outbreak and to recommend control measures. Investigation confirmed the presence of a new strain of norovirus GII.4 Sydney variant in stool specimens obtained from two wedding guests and on several environmental surfaces in the centre. In the questionnaire study, none of the foods or beverages served during the reception were significantly associated with the illness. Additional cases of gastroenteritis that occurred at the centre before and after the wedding reception supported the hypothesis of environmental transmission of norovirus. After thorough cleansing and disinfection and 1 week's quarantine, no new cases with symptoms typical for norovirus infection were identified at the centre.

  16. The influence of temperature, pH, and water immersion on the high hydrostatic pressure inactivation of GI.1 and GII.4 human noroviruses.

    PubMed

    Li, Xinhui; Chen, Haiqiang; Kingsley, David H

    2013-10-15

    Detection of human norovirus (HuNoV) usually relies on molecular biology techniques, such as qRT-PCR. Since histo-blood group antigens (HBGAs) are the functional receptors for HuNoV, HuNoV can bind to porcine gastric mucin (PGM), which contains HBGA-like antigens. In this study, PGM-conjugated magnetic beads were used to collect and quantify potentially infectious HuNoV strains GI.1 and GII.4 treated by high hydrostatic pressure (HHP). Both GI.1 and GII.4 strains used in this study showed increasing pressure sensitivity as judged by loss of PGM binding with decreasing temperature over a range of 1 to 35 °C. Both GI.1 and GII.4 were more resistant to pressure at pH4 than at neutral pH. Because GI.1 was significantly more resistant to pressure than GII.4, it was used to evaluate HuNoV pressure inactivation in blueberries. GI.1 on dry blueberries was very resistant to pressure while immersion of blueberries in water during pressure treatments substantially enhanced the inactivation. For example, a 2 min-600 MPa treatment of dry blueberries at 1 and 21 °C resulted in <1-log reductions while a 2.7-log reduction of GI.1 was achieved by a treatment at 500 MPa for 2 min at 1 °C when blueberries were immersed in water. In total, this novel study provides unique information for designing pressure processing parameters (pressure, temperature, and time) and product formulations (such as pH) to inactivate HuNoV in high-risk foods such as berries.

  17. Evaluation of Immunomagnetic Separation Method for the Recovery of Hepatitis A Virus and GI.1 and GII.4 Norovirus Strains Seeded on Oyster and Mussel.

    PubMed

    Ha, Ji-Hyoung; Choi, Changsun; Ha, Sang-Do

    2014-12-01

    Outbreaks of viral diseases are frequently associated with the consumption of minimally processed shellfish. Among the viruses in these outbreaks, hepatitis A virus (HAV) and human norovirus (NoV) have been increasingly reported as the most common food-borne pathogens. These viruses must be concentrated in tested samples in order to be detected. In this study, a method for the detection of NoV and HAV in shellfish using an immuno-magnetic separation (IMS) procedure combined with reverse transcriptase (RT)-PCR was developed. The IMS/RT-PCR method was applied to investigate the recovery rates of HAV, NoV GI.1, and GII.4 from oyster and mussel. Based on IMS/RT-PCR results, recovery rates for HAV from oyster and mussel test samples were 2.4 and 1.1%, respectively. The NoV GI.1 recovery rates from oyster and mussel samples were 4.9-9.2% (mean 6.9%) and 4.3-8.6% (mean 6.2%), respectively, and the NoV GII.4 recovery rates were 8.8 and 8.5%, respectively. These results verified that HAV, NoV GI.1, and GII.4 can be detected in all the test samples using the IMS/RT-PCR method, although the three inoculated viruses were recovered with low efficiency. In conclusion, the IMS/RT-PCR method can be used to efficiently and rapidly detect viruses such as HAV and NoV in shellfish such as oyster and mussel.

  18. Structural Analysis of Histo-Blood Group Antigen Binding Specificity in a Norovirus GII.4 Epidemic Variant: Implications for Epochal Evolution

    SciTech Connect

    Shanker, Sreejesh; Choi, Jae-Mun; Sankaran, Banumathi; Atmar, Robert L.; Estes, Mary K.; Prasad, B.V. Venkataram

    2012-03-23

    Susceptibility to norovirus (NoV), a major pathogen of epidemic gastroenteritis, is associated with histo-blood group antigens (HBGAs), which are also cell attachment factors for this virus. GII.4 NoV strains are predominantly associated with worldwide NoV epidemics with a periodic emergence of new variants. The sequence variations in the surface-exposed P domain of the capsid protein resulting in differential HBGA binding patterns and antigenicity are suggested to drive GII.4 epochal evolution. To understand how temporal sequence variations affect the P domain structure and contribute to epochal evolution, we determined the P domain structure of a 2004 variant with ABH and secretor Lewis HBGAs and compared it with the previously determined structure of a 1996 variant. We show that temporal sequence variations do not affect the binding of monofucosyl ABH HBGAs but that they can modulate the binding strength of difucosyl Lewis HBGAs and thus could contribute to epochal evolution by the potentiated targeting of new variants to Lewis-positive, secretor-positive individuals. The temporal variations also result in significant differences in the electrostatic landscapes, likely reflecting antigenic variations. The proximity of some of these changes to the HBGA binding sites suggests the possibility of a coordinated interplay between antigenicity and HBGA binding in epochal evolution. From the observation that the regions involved in the formation of the HBGA binding sites can be conformationally flexible, we suggest a plausible mechanism for how norovirus disassociates from salivary mucin-linked HBGA before reassociating with HBGAs linked to intestinal epithelial cells during its passage through the gastrointestinal tract.

  19. Simultaneous comparison of murine norovirus, feline calicivirus, coliphage MS2, and GII.4 norovirus to evaluate the efficacy of sodium hypochlorite against human norovirus on a fecally soiled stainless steel surface.

    PubMed

    Park, Geun Woo; Sobsey, Mark D

    2011-09-01

    Free chlorine as hypochlorite is recommended to decontaminate fecally contaminated surfaces to control human norovirus (NoV). We evaluated the efficacy of sodium hypochlorite to decontaminate GII.4 NoV and three surrogates of human NoVs, feline calicivirus (FCV), murine norovirus (MNV), and coliphage MS2, on a fecally soiled stainless steel surface. Reduction of infectivity of FCV, MNV, and MS2 was measured by plaque assay and the decline of genomic copy numbers of GII.4 NoV by reverse transcriptase-polymerase chain reaction. Sodium hypochlorite solution at 5000 ppm could inactivate FCV by 3 log(10) plaque forming units after approximately 1.9 minutes of contact time, but required longer exposure times of 3.2 and 4.5 minutes to reduce MNV and MS2 by 3 log(10), respectively. However, detection of viral RNA by reverse transcriptase-polymerase chain reaction assay may not be reliable to estimate the effectiveness of sodium hypochlorite against human NoV. Of three NoV surrogates, FCV is not the most resistant of the virus tested for inactivation by hypochlorite and thus is not the worst-case model for estimating NoV inactivation. Although the use of 5000 ppm of hypochlorite for fecally soiled surfaces is effective, it may require longer exposure times of ≥3 minutes to control NoVs. Surface precleaning before hypochlorite disinfection is recommended to initially reduce the fecal organic load for better virus inactivation and should be a part of the environmental hygiene response measures during an NoV outbreak or where NoV fecal contamination of environmental surfaces is likely or suspected to be present.

  20. Evaluation of a Porcine Gastric Mucin and RNase A Assay for the Discrimination of Infectious and Non-infectious GI.1 and GII.4 Norovirus Following Thermal, Ethanol, or Levulinic Acid Plus Sodium Dodecyl Sulfate Treatments.

    PubMed

    Afolayan, Olamide T; Webb, Cathy C; Cannon, Jennifer L

    2016-03-01

    Human noroviruses (NoVs) are a major source of foodborne illnesses worldwide. Since human NoVs cannot be cultured in vitro, methods that discriminate infectious from non-infectious NoVs are needed. The purpose of this study was to evaluate binding of NoV genotypes GI.1 and GII.4 to histo-blood group antigens expressed in porcine gastric mucin (PGM) as a surrogate for detecting infectious virus following thermal (99 °C/5 min), 70% ethanol or 0.5% levulinic acid (LV) plus 0.01 or 0.1% sodium dodecyl sulfate (SDS) sanitizer treatments and to determine the limit of detection of GI.1 and GII.4 binding to PGM. Treated and control virus samples were applied to 96-well plates coated with 1 µg/ml PGM followed by RNase A (5 ng/µl) treatment for degradation of exposed RNA. Average log genome copies per ml (gc/ml) reductions and relative differences (RD) in quantification cycle (Cq) values after thermal treatment were 1.77/5.62 and 1.71/7.25 (RNase A) and 1.73/5.50 and 1.56/6.58 (no RNase A) for GI.1 and GII.4, respectively. Treatment of NoVs with 70% EtOH resulted in 0.05/0.16 (GI.1) and 3.54/10.19 (GII.4) log reductions in gc/ml and average RD in Cq value, respectively. LV (0.5%) combined with 0.1 % SDS provided a greater decrease of GI.1 and GII.4 NoVs with 8.97 and 8.13 average RD in Cq values obtained, respectively than 0.5% LV/0.01 % SDS. Virus recovery after PGM binding was variable with GII.4 > GI.1. PGM binding is a promising surrogate for identifying infectious and non-infectious NoVs after capsid destruction, however, results vary depending on virus strain and inactivation method.

  1. The influence of temperature pH and water immersion on the high hydrostatic pressure inactivation of GI.1 and GII.4 human noroviruses

    USDA-ARS?s Scientific Manuscript database

    Detection of human norovirus (HuNoV) usually relies on molecular biology techniques, such as qRT PCR. Since histo-blood group antigens (HBGAs) are the functional receptors for HuNoV, HuNoV can bind to porcine gastric mucin (PGM), which contains HBGA-like antigens. In this study, PGM conjugated magn...

  2. Norovirus

    MedlinePlus

    ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology About Norovirus Language: English Español (Spanish) Recommend on ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology Language: English Español (Spanish) File Formats Help: How ...

  3. Norovirus

    MedlinePlus

    ... of scientists at Baylor College of Medicine in Texas, who recently developed a way to grow human ... Frequently Asked Questions Norovirus Reporting in Calicinet CaliciNet Data Participating Labs References and Resources NoroSTAT NoroSTAT Data ...

  4. Norovirus

    PubMed Central

    Robilotti, Elizabeth; Deresinski, Stan

    2015-01-01

    SUMMARY Norovirus, an RNA virus of the family Caliciviridae, is a human enteric pathogen that causes substantial morbidity across both health care and community settings. Several factors enhance the transmissibility of norovirus, including the small inoculum required to produce infection (<100 viral particles), prolonged viral shedding, and its ability to survive in the environment. In this review, we describe the basic virology and immunology of noroviruses, the clinical disease resulting from infection and its diagnosis and management, as well as host and pathogen factors that complicate vaccine development. Additionally, we discuss overall epidemiology, infection control strategies, and global reporting efforts aimed at controlling this worldwide cause of acute gastroenteritis. Prompt implementation of infection control measures remains the mainstay of norovirus outbreak management. PMID:25567225

  5. Strain-Specific Virolysis Patterns of Human Noroviruses in Response to Alcohols

    PubMed Central

    Park, Geun Woo; Collins, Nikail; Barclay, Leslie; Hu, Liya; Prasad, B. V. Venkataram; Lopman, Benjamin A.; Vinjé, Jan

    2016-01-01

    Alcohol-based hand sanitizers are widely used to disinfect hands to prevent the spread of pathogens including noroviruses. Alcohols inactivate norovirus by destruction of the viral capsid, resulting in the leakage of viral RNA (virolysis). Since conflicting results have been reported on the susceptibility of human noroviruses against alcohols, we exposed a panel of 30 human norovirus strains (14 GI and 16 GII strains) to different concentrations (50%, 70%, 90%) of ethanol and isopropanol and tested the viral RNA titer by RT-qPCR. Viral RNA titers of 10 (71.4%), 14 (100%), 3 (21.4%) and 7 (50%) of the 14 GI strains were reduced by > 1 log10 RNA copies/ml after exposure to 70% and 90% ethanol, and 70% and 90% isopropanol, respectively. RNA titers of 6 of the 7 non-GII 4 strains remained unaffected after alcohol exposure. Compared to GII strains, GI strains were more susceptible to ethanol than to isopropanol. At 90%, both alcohols reduced RNA titers of 8 of the 9 GII.4 strains by ≥ 1 log10 RNA copies/ml. After exposure to 70% ethanol, RNA titers of GII.4 Den Haag and Sydney strains decreased by ≥ 1.9 log10, whereas RNA reductions for GII.4 New Orleans strains were < 0.5 log10. To explain these differences, we sequenced the complete capsid gene of the 9 GII.4 strains and identified 17 amino acid substitutions in the P2 region among the 3 GII.4 variant viruses. When comparing with an additional set of 200 GII.4 VP1 sequences, only S310 and P396 were present in all GII.4 New Orleans viruses but not in the ethanol-sensitive GII.4 Sydney and GII.4 Den Haag viruses Our data demonstrate that alcohol susceptibility patterns between different norovirus genotypes vary widely and that virolysis data for a single strain or genotype are not representative for all noroviruses. PMID:27337036

  6. Identification of the novel Kawasaki 2014 GII.17 human norovirus strain in Italy, 2015.

    PubMed

    Medici, Maria Cristina; Tummolo, Fabio; Calderaro, Adriana; Chironna, Maria; Giammanco, Giovanni Maurizio; De Grazia, Simona; Arcangeletti, Maria Cristina; De Conto, Flora; Chezzi, Carlo; Martella, Vito

    2015-01-01

    Surveillance of noroviruses in Italy identified the novel GII.17 human norovirus strain, Kawasaki 2014, in February 2015. This novel strain emerged as a major cause of gastroenteritis in Asia during 2014/15, replacing the pandemic GII.4 norovirus strain Sydney 2012, but being reported only sporadically elsewhere. This novel strain is undergoing fast diversification and continuous monitoring is important to understand the evolution of noroviruses and to implement the future strategies on norovirus vaccines.

  7. Surveillance of norovirus in Portugal and the emergence of the Sydney variant, 2011-2013.

    PubMed

    Costa, I; Mesquita, J R; Veiga, E; Oleastro, M; Nascimento, M J S

    2015-09-01

    This report presents the results of the national surveillance system of diarrhea etiology of the National Institute of Health of Portugal concerning norovirus (NoV) during a two-year period, May 2011-2013. Of the total 580 stool samples collected from patients hospitalized for acute diarrhea in 13 Hospitals of Portugal, 67 (11.6%) tested positive for NoV. From May 2011 to March 2012 the GII.4 variant New Orleans 2009 was the most predominant strain having been replaced by the new GII.4 variant Sydney 2012 since then till the end of the survey. To our knowledge this is the first study showing the circulation of GII.4 as the norovirus strain most commonly associated to gastroenteritis and the first to report the replacement of GII.4 New Orleans by GII.4 Sydney 2012 variant in Portugal.

  8. Norovirus Genotype Profiles Associated with Foodborne Transmission, 1999�?"2012

    PubMed Central

    Hewitt, Joanne; Barclay, Leslie; Ahmed, Sharia; Lake, Rob; Hall, Aron J.; Lopman, Ben; Kroneman, Annelies; Vennema, Harry; VinjA(c), Jan; Koopmans, Marion

    2015-01-01

    Worldwide, noroviruses are a leading cause of gastroenteritis. They can be transmitted from person to person directly or indirectly through contaminated food, water, or environments. To estimate the proportion of foodborne infections caused by noroviruses on a global scale, we used norovirus transmission and genotyping information from multiple international outbreak surveillance systems (Noronet, CaliciNet, EpiSurv) and from a systematic review of peer-reviewed literature. The proportion of outbreaks caused by food was determined by genotype and/or genogroup. Analysis resulted in the following final global profiles: foodborne transmission is attributed to 10% (range 9%%�?"11%) of all genotype GII.4 outbreaks, 27% (25%�?"30%) of outbreaks caused by all other single genotypes, and 37% (24%%�?"52%) of outbreaks caused by mixtures of GII.4 and other noroviruses. When these profiles are applied to global outbreak surveillance data, results indicate that �%^14% of all norovirus outbreaks are attributed to food. PMID:25811368

  9. RNA Populations in Immunocompromised Patients as Reservoirs for Novel Norovirus Variants

    PubMed Central

    Donaldson, Eric; Huynh, Jeremy; Barclay, Leslie; Lopman, Ben; Baric, Ralph; Chen, Luke F.; Vinjé, Jan

    2014-01-01

    ABSTRACT Noroviruses are the leading cause of acute gastroenteritis outbreaks worldwide. The majority of norovirus outbreaks are caused by genogroup II.4 (GII.4). Novel GII.4 strains emerge every 2 to 4 years and replace older variants as the dominant norovirus. Novel variants emerge through a combination of recombination, genetic drift, and selection driven by population immunity, but the exact mechanism of how or where is not known. We detected two previously unknown novel GII.4 variants, termed GII.4 UNK1 and GII.4 UNK2, and a diverse norovirus population in fecal specimens from immunocompromised individuals with diarrhea after they had undergone bone marrow transplantation. We hypothesized that immunocompromised individuals can serve as reservoirs for novel norovirus variants. To test our hypothesis, metagenomic analysis of viral RNA populations was combined with a full-genome bioinformatic analysis of publicly available GII.4 norovirus sequences from 1974 to 2014 to identify converging sites. Variable sites were proportionally more likely to be within two amino acids (P < 0.05) of positively selected sites. Further analysis using a hypergeometric distribution indicated that polymorphic site distribution was random and its proximity to positively selected sites was dependent on the size of the norovirus genome and the number of positively selected sites.In conclusion, random mutations may have a positive impact on driving norovirus evolution, and immunocompromised individuals could serve as potential reservoirs for novel GII.4 strains. IMPORTANCE Norovirus is the most common cause of viral gastroenteritis in the United States. Every 2 to 3 years novel norovirus variants emerge and replace dominant strains. The continual emergence of novel noroviruses is believed to be caused by a combination of genetic drift, population immunity, and recombination, but exactly how this emergence occurs remains unknown. In this study, we identified two novel GII.4 variants in

  10. Evaluation of the updated RIDA®QUICK (Version N1402) immunochromatographic assay for the detection of norovirus in clinical specimens.

    PubMed

    Bruggink, Leesa D; Dunbar, Natalie L; Marshall, John A

    2015-10-01

    The sensitivity and specificity of the R-Biopharm RIDA(®)QUICK (N1402) immunochromatography assay for norovirus detection was examined using fecal material from Australian gastroenteritis incidents. The study involved the analysis of 3 groups of specimens; group 1 comprised 100 norovirus open reading frame (ORF) 1 RT-PCR positive specimens; group 2 comprised 100 ORF 1 RT-PCR norovirus negative specimens and group 3 comprised 12 specimens containing common gastroenteritis viruses other than norovirus. The RIDA(®)QUICK (N1402) assay detected both GI and GII norovirus and had an overall sensitivity of 87%. Genotype analysis of the capsid region of the genome (ORF 2) indicated the RIDA(®)QUICK (N1402) assay could detect a range of genotypes including GI.1, GI.2, GI.3, GI.4, GI.5, GII.3, GII.4 (including variants GII.4 (2009-like), GII.4 (2012), GII.4 (2012-like) and GII.4 (unknown)), GII.6, GII.13 and GII.21. The assay had good sensitivity for both GI and GII norovirus. The assay had a specificity of 97% and did not cross react with a number of common fecal viruses. However, one of eight rotavirus positive, norovirus negative specimens gave a positive result; rotavirus cannot be taken as the cause of such a false positive but cannot be excluded either. The kit was quick and easy to use and would be valuable in point-of-care testing. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Norovirus infection in Belarus: occurrence and molecular epidemiology.

    PubMed

    Paklonskayal, Natallia Uladzimirauna; Amvrosieva, Tamara Vasil'evna; Dziadziulia, Kanstantsin Leanidavich; Baranouskaya, Natallia Mikalaeuna; Kishkurno, Elena Petrovna; Kluiko, Nina Leonidovna

    2015-03-01

    The objective of the study is to analyze molecular epidemiologic surveillance for norovirus infection in Belarus over the past five years (2009-2013). Laboratory diagnostics was carried out by RT-PCR in 684 patients. Two regions of norovirus genome, localized in RNA-polymerase and capsid protein genes, were used for phylogenetic analysis. Noroviruses were predominant causative agents in adults and second only to rotaviruses in children, they also prevailed among aetiological agents of outbreaks (66.7% of outbreaks). In 2009-2013, the major norovirus genotype was GII.4 (58.3% of all genotyped isolates). Genovariant GII.4 2006b circulated in 2009 and 2010, genovariant GII.4 2009 New Orleans - in 2010 and 2012. In addition to GII.4, genotypes GII.6 (16.6%), GII.2 (4.1%), GII.3 (2.2%), and recombinant genotypes GII.g-GII.12 and GII.g-GII.1 (10.4% and 8.3%, respectively) circulated in Belarus. The findings indicate a significant contribution of noroviruses in development of sporadic morbidity and outbreaks of acute gastroenteritis in Belarus. Outbreaks or prominent increases of sporadic morbidity were mostly due to the emergence of a new genotype, or an epidemic genovariant.

  12. Norovirus - hospital

    MedlinePlus

    Gastroenteritis - norovirus; Colitis - norovirus; Hospital acquired infection - norovirus ... fluids ( dehydration ). Anyone can become infected with norovirus. Hospital patients who are very old, very young, or ...

  13. Norovirus genotype diversity in community-based sporadic gastroenteritis incidents: a five-year study.

    PubMed

    Bruggink, Leesa D; Dunbar, Natalie L; Marshall, John A

    2015-06-01

    Although norovirus is a known cause of sporadic gastroenteritis, the incidence and genotypes of norovirus associated with sporadic community-based gastroenteritis are poorly understood. The current study examined this issue by using material from alleged food poisoning incidents in the state of Victoria, Australia, for the period 2008-2012. Norovirus was identified, by either ORF (open reading frame) 1 or ORF 2 RT-PCR methodology, in 159 of 379 (42.0%) sporadic gastroenteritis incidents, thereby showing that norovirus was an important cause of sporadic gastroenteritis. The number of sporadic norovirus incidents did not vary significantly from year to year, indicating that the pool of circulating norovirus remained constant. Norovirus ORF 1 genotypes identified included GI.1, GI.2, GI.3, GI.4, GI.b, GI.d, GII.2, GII.4 (including variants 2006a, 2006b, 2007, and 2009), GII.16, GII.22, GII.b, GII.e, and GII.g. Norovirus ORF 2 genotypes identified included GI.1, GI.2, GI.3, GI.4, GI.6, GII.2, GII.3, GII.4 (variants 2006b, 2009, 2009-like, 2012, and "unknown"), GII.6, GII.7, GII.9, GII.12, and GII.13. Five ORF 1/ORF 2 norovirus recombinant forms were confirmed: GII.b/GII.3, GII.e/GII.4 (2012), GII.e/GII.4 (unknown), GII.g/GII.12 and GII.16/GII.2. Although the incidence of ORF 2 GI.3 was significantly higher in children than in adults, this was not the case for other major ORF 2 genotypes (GII.2, GII.4, and GII.6) which occurred equally in all age groups. The findings demonstrate the importance and diverse nature of norovirus in sporadic community-based gastroenteritis incidents and indicate that the development of successful vaccine strategies may be difficult. © 2015 Wiley Periodicals, Inc.

  14. Epidemiology of Norovirus Infection Among Immunocompromised Patients at a Tertiary Care Research Hospital, 2010–2013

    PubMed Central

    Bok, Karin; Prevots, D. Rebecca; Binder, Alison M.; Parra, Gabriel I.; Strollo, Sara; Fahle, Gary A.; Behrle-Yardley, Allison; Johnson, Jordan A.; Levenson, Eric A.; Sosnovtsev, Stanislav V.; Holland, Steven M.; Palmore, Tara N.; Green, Kim Y.

    2016-01-01

    Background. Noroviruses are a major cause of infectious gastroenteritis worldwide, and viruses can establish persistent infection in immunocompromised individuals. Risk factors and transmission in this population are not fully understood. Methods. From 2010 through 2013, we conducted a retrospective review among immunocompromised patients (n = 268) enrolled in research studies at the National Institutes of Health Clinical Center and identified a subset of norovirus-positive patients (n = 18) who provided stool specimens for norovirus genotyping analysis. Results. Norovirus genome was identified by reverse-transcription quantitative polymerase chain reaction in stools of 35 (13%) of the 268 immunocompromised patients tested, and infection prevalence was 21% (11 of 53) in persons with primary immune deficiencies and 12% (20 of 166) among persons with solid tumors or hematologic malignancies. Among 18 patients with norovirus genotyping information, norovirus GII.4 was the most prevalent genotype (14 of 18, 78%). Persistent norovirus infection (≥6 months) was documented in 8 of 18 (44%) individuals. Phylogenetic analysis of the GII.4 capsid protein sequences identified at least 5 now-displaced GII.4 variant lineages, with no evidence of their nosocomial transmission in the Clinical Center. Conclusions. Norovirus was a leading enteric pathogen identified in this immunocompromised population. Both acute and chronic norovirus infections were observed, and these were likely community-acquired. Continued investigation will further define the role of noroviruses in these patients and inform efforts toward prevention and treatment. PMID:27800529

  15. Epidemiology of Norovirus Infection Among Immunocompromised Patients at a Tertiary Care Research Hospital, 2010-2013.

    PubMed

    Bok, Karin; Prevots, D Rebecca; Binder, Alison M; Parra, Gabriel I; Strollo, Sara; Fahle, Gary A; Behrle-Yardley, Allison; Johnson, Jordan A; Levenson, Eric A; Sosnovtsev, Stanislav V; Holland, Steven M; Palmore, Tara N; Green, Kim Y

    2016-09-01

    Background.  Noroviruses are a major cause of infectious gastroenteritis worldwide, and viruses can establish persistent infection in immunocompromised individuals. Risk factors and transmission in this population are not fully understood. Methods.  From 2010 through 2013, we conducted a retrospective review among immunocompromised patients (n = 268) enrolled in research studies at the National Institutes of Health Clinical Center and identified a subset of norovirus-positive patients (n = 18) who provided stool specimens for norovirus genotyping analysis. Results.  Norovirus genome was identified by reverse-transcription quantitative polymerase chain reaction in stools of 35 (13%) of the 268 immunocompromised patients tested, and infection prevalence was 21% (11 of 53) in persons with primary immune deficiencies and 12% (20 of 166) among persons with solid tumors or hematologic malignancies. Among 18 patients with norovirus genotyping information, norovirus GII.4 was the most prevalent genotype (14 of 18, 78%). Persistent norovirus infection (≥6 months) was documented in 8 of 18 (44%) individuals. Phylogenetic analysis of the GII.4 capsid protein sequences identified at least 5 now-displaced GII.4 variant lineages, with no evidence of their nosocomial transmission in the Clinical Center. Conclusions.  Norovirus was a leading enteric pathogen identified in this immunocompromised population. Both acute and chronic norovirus infections were observed, and these were likely community-acquired. Continued investigation will further define the role of noroviruses in these patients and inform efforts toward prevention and treatment.

  16. Comparison of norovirus genogroup I, II and IV seroprevalence among children in the Netherlands, 1963, 1983 and 2006.

    PubMed

    van Beek, Janko; de Graaf, Miranda; Xia, Ming; Jiang, Xi; Vinjé, Jan; Beersma, Mathias; de Bruin, Erwin; van de Vijver, David; Holwerda, Melle; van Houten, Marlies; Buisman, Annemarie M; van Binnendijk, Rob; Osterhaus, Albert D M E; van der Klis, Fiona; Vennema, Harry; Koopmans, Marion P G

    2016-09-01

    Noroviruses are a major cause of acute gastroenteritis worldwide and are a genetically diverse group of viruses. Since 2002, an increasing number of norovirus outbreaks have been reported globally, but it is not clear whether this increase has been caused by a higher awareness or reflects the emergence of new genogroup II genotype 4 (GII.4) variants. The hypothesis that norovirus prevalence has increased post-2002 and is related to the emergence of GII.4 is tested in this study. Sera collected from children aged <5 years of three Dutch cross-sectional population based cohorts in 1963, 1983 and 2006/2007 (n=143, n=130 and n=376, respectively) were tested for specific serum IgG by protein array using antigens to GII.4 and a range of other antigens representing norovirus GI, GII and GIV genotypes. The protein array was validated by paired sera of norovirus infected patients and supernatants of B-cell cultures with single epitope specificity. Evidence for norovirus infection was found to be common among Dutch children in each cohort, but the prevalence towards different genotypes changed over time. At the genogroup level, GI seroprevalence decreased significantly between 1963 and 2006/2007, while a significant increase of GII and, in particular, specific antibodies of the genotype GII.4 was detected in the 2006/2007 cohort. There were no children with only GII.4 antibodies in the 1963 cohort. This study shows that the high GII.4 norovirus incidence in very young children is a recent phenomenon. These findings are of importance for vaccine development and trials that are currently focusing mostly on GII.4 viruses.

  17. Genotypic and Epidemiologic Trends of Norovirus Outbreaks in the United States, 2009 to 2013

    PubMed Central

    Barclay, Leslie; Gregoricus, Nicole; Shirley, S. Hannah; Lee, David

    2014-01-01

    Noroviruses are the leading cause of epidemic acute gastroenteritis in the United States. From September 2009 through August 2013, 3,960 norovirus outbreaks were reported to CaliciNet. Of the 2,895 outbreaks with a known transmission route, person-to-person and food-borne transmissions were reported for 2,425 (83.7%) and 465 (16.1%) of the outbreaks, respectively. A total of 2,475 outbreaks (62.5%) occurred in long-term care facilities (LTCF), 389 (9.8%) in restaurants, and 227 (5.7%) in schools. A total of 435 outbreaks (11%) were typed as genogroup I (GI) and 3,525 (89%) as GII noroviruses. GII.4 viruses caused 2,853 (72%) of all outbreaks, of which 94% typed as either GII.4 New Orleans or GII.4 Sydney. In addition, three non-GII.4 viruses, i.e., GII.12, GII.1, and GI.6, caused 528 (13%) of all outbreaks. Several non-GII.4 genotypes (GI.3, GI.6, GI.7, GII.3, GII.6, and GII.12) were significantly more associated with food-borne transmission (odds ratio, 1.9 to 7.1; P < 0.05). Patients in LTCF and people ≥65 years of age were at higher risk for GII.4 infections than those in other settings and with other genotypes (P < 0.05). Phylogeographic analysis identified three major dispersions from two geographic locations that were responsible for the GI.6 outbreaks from 2011 to 2013. In conclusion, our data demonstrate the cyclic emergence of new (non-GII.4) norovirus strains, and several genotypes are more often associated with food-borne outbreaks. These surveillance data can be used to improve viral food-borne surveillance and to help guide studies to develop and evaluate targeted prevention methods such as norovirus vaccines, antivirals, and environmental decontamination methods. PMID:24172151

  18. Genotypic and epidemiologic trends of norovirus outbreaks in the United States, 2009 to 2013.

    PubMed

    Vega, Everardo; Barclay, Leslie; Gregoricus, Nicole; Shirley, S Hannah; Lee, David; Vinjé, Jan

    2014-01-01

    Noroviruses are the leading cause of epidemic acute gastroenteritis in the United States. From September 2009 through August 2013, 3,960 norovirus outbreaks were reported to CaliciNet. Of the 2,895 outbreaks with a known transmission route, person-to-person and food-borne transmissions were reported for 2,425 (83.7%) and 465 (16.1%) of the outbreaks, respectively. A total of 2,475 outbreaks (62.5%) occurred in long-term care facilities (LTCF), 389 (9.8%) in restaurants, and 227 (5.7%) in schools. A total of 435 outbreaks (11%) were typed as genogroup I (GI) and 3,525 (89%) as GII noroviruses. GII.4 viruses caused 2,853 (72%) of all outbreaks, of which 94% typed as either GII.4 New Orleans or GII.4 Sydney. In addition, three non-GII.4 viruses, i.e., GII.12, GII.1, and GI.6, caused 528 (13%) of all outbreaks. Several non-GII.4 genotypes (GI.3, GI.6, GI.7, GII.3, GII.6, and GII.12) were significantly more associated with food-borne transmission (odds ratio, 1.9 to 7.1; P < 0.05). Patients in LTCF and people ≥65 years of age were at higher risk for GII.4 infections than those in other settings and with other genotypes (P < 0.05). Phylogeographic analysis identified three major dispersions from two geographic locations that were responsible for the GI.6 outbreaks from 2011 to 2013. In conclusion, our data demonstrate the cyclic emergence of new (non-GII.4) norovirus strains, and several genotypes are more often associated with food-borne outbreaks. These surveillance data can be used to improve viral food-borne surveillance and to help guide studies to develop and evaluate targeted prevention methods such as norovirus vaccines, antivirals, and environmental decontamination methods.

  19. Genetic characterization of norovirus strains in hospitalized children from Pakistan.

    PubMed

    Alam, Amna; Qureshi, Sohail A; Vinjé, Jan; Zaidi, Anita

    2016-02-01

    Norovirus is one of the most common causes of acute gastroenteritis among children in developing countries. No data on the prevalence and genetic variability of norovirus are available for Pakistan, where early childhood mortality due to acute gastroenteritis is common. We tested 255 fecal specimens from children under 5 years of age hospitalized between April 2006 and March 2008 with severe acute gastroenteritis in five hospitals in the four largest cities in Pakistan for norovirus by real-time RT-PCR. Positive samples were further genotyped by conventional RT-PCR targeting the 5'-end of the capsid gene followed by sequencing of the positive PCR products. Overall, 41 (16.1%) samples tested positive for norovirus with an equal frequency in rotavirus-positive and rotavirus-negative samples. Nine (22%) samples were genogroup (G)I positive, 30 (73%) GII positive and two (5%) samples contained a mixture of GI and GII viruses. Sequence analyses demonstrated co-circulation of 14 norovirus genotypes including four GI genotypes (GI.3, GI.5, GI.7, GI.8) and 10 GII genotypes (GII.2, GII.3, GII.4, GII.5, GII.6, GII.7, GII.9, GII.13, GII.16, and GII.21). The most prevalent genotypes were GI.7 and GII.4 both causing 12.2% of the infections. This report confirms the presence of multiple norovirus genotypes in hospitalized children with acute gastroenteritis in Pakistan and a lack of clear predominance of GII.4 viruses.

  20. Pediatric Norovirus Diarrhea in Nicaragua▿

    PubMed Central

    Bucardo, Filemon; Nordgren, Johan; Carlsson, Beatrice; Paniagua, Margarita; Lindgren, Per-Eric; Espinoza, Felix; Svensson, Lennart

    2008-01-01

    Information about norovirus (NoV) infections in Central America is limited. Through a passive community and hospital pediatric diarrhea surveillance program, a total of 542 stool samples were collected between March 2005 and February 2006 in León, Nicaragua. NoV was detected in 12% (65/542) of the children; of these, 11% (45/409) were in the community and 15% (20/133) were in the hospital, with most strains (88%) belonging to genogroup II. NoV infections were age and gender associated, with children of <2 years of age (P < 0.05) and girls (P < 0.05) being most affected. Breast-feeding did not reduce the number of NoV infections. An important proportion (57%) of NoV-infected children were coinfected with diarrheagenic Escherichia coli. A significant proportion (18/31) of NoV-positive children with dehydration required intravenous rehydration. Nucleotide sequence analysis (38/65) of the N-terminal and shell region in the capsid gene revealed that at least six genotypes (GI.4, GII.2, GII.4, GII.7, GII.17, and a potentially novel cluster termed “GII.18-Nica”) circulated during the study period, with GII.4 virus being predominant (26/38). The majority (20/26) of those GII.4 strains shared high nucleotide homology (99%) with the globally emerging Hunter strain. The mean viral load was approximately 15-fold higher in children infected with GII.4 virus than in those infected with other G.II viruses, with the highest viral load observed for the group of children infected with GII.4 and requiring intravenous rehydration. This study, the first of its type from a Central American country, suggests that NoV is an important etiological agent of acute diarrhea among children of <2 years of age in Nicaragua. PMID:18562593

  1. Static and Evolving Norovirus Genotypes: Implications for Epidemiology and Immunity.

    PubMed

    Parra, Gabriel I; Squires, R Burke; Karangwa, Consolee K; Johnson, Jordan A; Lepore, Cara J; Sosnovtsev, Stanislav V; Green, Kim Y

    2017-01-01

    Noroviruses are major pathogens associated with acute gastroenteritis worldwide. Their RNA genomes are diverse, with two major genogroups (GI and GII) comprised of at least 28 genotypes associated with human disease. To elucidate mechanisms underlying norovirus diversity and evolution, we used a large-scale genomics approach to analyze human norovirus sequences. Comparison of over 2000 nearly full-length ORF2 sequences representing most of the known GI and GII genotypes infecting humans showed a limited number (≤5) of distinct intra-genotypic variants within each genotype, with the exception of GII.4. The non-GII.4 genotypes were comprised of one or more intra-genotypic variants, with each variant containing strains that differed by only a few residues over several decades (remaining "static") and that have co-circulated with no clear epidemiologic pattern. In contrast, the GII.4 genotype presented the largest number of variants (>10) that have evolved over time with a clear pattern of periodic variant replacement. To expand our understanding of these two patterns of diversification ("static" versus "evolving"), we analyzed using NGS the nearly full-length norovirus genome in healthy individuals infected with GII.4, GII.6 or GII.17 viruses in different outbreak settings. The GII.4 viruses accumulated mutations rapidly within and between hosts, while the GII.6 and GII.17 viruses remained relatively stable, consistent with their diversification patterns. Further analysis of genetic relationships and natural history patterns identified groupings of certain genotypes into larger related clusters designated here as "immunotypes". We propose that "immunotypes" and their evolutionary patterns influence the prevalence of a particular norovirus genotype in the human population.

  2. Static and Evolving Norovirus Genotypes: Implications for Epidemiology and Immunity

    PubMed Central

    Karangwa, Consolee K.; Sosnovtsev, Stanislav V.

    2017-01-01

    Noroviruses are major pathogens associated with acute gastroenteritis worldwide. Their RNA genomes are diverse, with two major genogroups (GI and GII) comprised of at least 28 genotypes associated with human disease. To elucidate mechanisms underlying norovirus diversity and evolution, we used a large-scale genomics approach to analyze human norovirus sequences. Comparison of over 2000 nearly full-length ORF2 sequences representing most of the known GI and GII genotypes infecting humans showed a limited number (≤5) of distinct intra-genotypic variants within each genotype, with the exception of GII.4. The non-GII.4 genotypes were comprised of one or more intra-genotypic variants, with each variant containing strains that differed by only a few residues over several decades (remaining “static”) and that have co-circulated with no clear epidemiologic pattern. In contrast, the GII.4 genotype presented the largest number of variants (>10) that have evolved over time with a clear pattern of periodic variant replacement. To expand our understanding of these two patterns of diversification (“static” versus “evolving”), we analyzed using NGS the nearly full-length norovirus genome in healthy individuals infected with GII.4, GII.6 or GII.17 viruses in different outbreak settings. The GII.4 viruses accumulated mutations rapidly within and between hosts, while the GII.6 and GII.17 viruses remained relatively stable, consistent with their diversification patterns. Further analysis of genetic relationships and natural history patterns identified groupings of certain genotypes into larger related clusters designated here as “immunotypes”. We propose that “immunotypes” and their evolutionary patterns influence the prevalence of a particular norovirus genotype in the human population. PMID:28103318

  3. Genotype analysis of noroviruses associated with gastroenteritis outbreaks in childcare centres, Victoria, Australia, 2012-2015.

    PubMed

    Bruggink, L D; Moselen, J M; Marshall, J A

    2017-07-01

    The characteristics of norovirus outbreaks in children (0-5 years) in childcare centres in Victoria, Australia (2012-2015) were examined. The three most common open reading frame (ORF) 2 genotypes in childcare centre outbreaks were GII.4 (42%), GII.6 (21%) and GII.3 (14%); the remaining genotypes (GI.2, GI.3, GI.4, GI.8, GI.13, GII.1, GII.2, GII.7 and GII.13) each made up <10%. The GII.4 genotype was the only norovirus genotype seen in all 4 years of the study and was the most common genotype in 2012-2014 but in 2015 the most common genotype was GII.2. The GII.4 genotype was more common in children 0-2 years, whereas GII.2 and GII.7 were more common in children 4-5 years. ORF 1/ORF 2 recombinant forms identified were GII.P4_NewOrleans_2009/GII.4_Sydney_2012, GII.P12/GII.3, GII.Pb (GII.21)/GII.3, GII.Pe/GII.2, GII.Pe/GII.4_Sydney_2012 and GII.Pg/GII.1. The findings indicate that norovirus genotype prevalence patterns in children were influenced by the age of the children and the year in which the analysis was carried out. The majority of norovirus infections (84%) occurred after the first year of life so that vaccination before the age of one would appear to be the most efficacious.

  4. What Is the Reservoir of Emergent Human Norovirus Strains?

    PubMed Central

    Baric, Ralph S.

    2015-01-01

    Since 1996, there have been at least six human norovirus pandemics. All of the pandemic strains are genetically related, segregating in the genogroup II, genotype 4 (GII.4) cluster within the Norovirus genus. Evidence indicates that these strains are closely related but antigenically distinct, supporting immune-driven viral evolution. Thus, norovirus vaccines will likely require periodic reformulation to protect from newly emergent strains. A major obstacle is that the reservoir of emergent strains is unknown. Noroviruses display tight species specificity and there is no evidence supporting zoonotic transmission, so an animal reservoir is considered unlikely. Moreover, available data indicate minimal viral diversity in most natural human infections. In this Gem, we discuss the widely speculated idea that chronically infected immunocompromised individuals are norovirus reservoirs and provide a rationale for the theory that elderly and malnourished hosts may also represent norovirus reservoirs. PMID:25787285

  5. Different norovirus genotypes in patients with gastroenteritis in Kuwait.

    PubMed

    Al-Rashidi, Amirah; Chehadeh, Wassim; Szücs, György G; Albert, M John

    2013-09-01

    Norovirus is a leading cause of acute gastroenteritis worldwide. The importance of this virus infection in Kuwait is not known. Eight out of 100 stool samples (8.0%) from children up to 5 years of age with gastroenteritis studied during 2006-2007 from one hospital, and 6 out of 70 stool samples (8.5%) from similar children studied from another hospital during 2010-2011 were positive for norovirus by RT-PCR. Out of these 170 samples studied from both hospitals, 10 samples were positive for norovirus when tested by ELISA. Phylogenetic tree analysis of norovirus strains showed that 50% of the norovirus strains belonged to genotype GII.4, and the predominant strain was GII.4 2006b. Other detected genotypes were GII.12, GII.b, GII.3, GII.8, and GII.7. This study highlights the importance of screening for norovirus infection in acute gastroenteritis and having a reporting system to understand better the epidemiology of norovirus infection in Kuwait.

  6. Norovirus Gastroenteritis in a Birth Cohort in Southern India.

    PubMed

    Menon, Vipin Kumar; George, Santosh; Sarkar, Rajiv; Giri, Sidhartha; Samuel, Prasanna; Vivek, Rosario; Saravanabavan, Anuradha; Liakath, Farzana Begum; Ramani, Sasirekha; Iturriza-Gomara, Miren; Gray, James J; Brown, David W; Estes, Mary K; Kang, Gagandeep

    2016-01-01

    Noroviruses are an important cause of gastroenteritis but little is known about disease and re-infection rates in community settings in Asia. Disease, re-infection rates, strain prevalence and genetic susceptibility to noroviruses were investigated in a birth cohort of 373 Indian children followed up for three years. Stool samples from 1856 diarrheal episodes and 147 vomiting only episodes were screened for norovirus by RT-PCR. Norovirus positivity was correlated with clinical data, secretor status and ABO blood group. Of 1856 diarrheal episodes, 207 (11.2%) were associated with norovirus, of which 49(2.6%) were norovirus GI, 150(8.1%) norovirus GII, and 8 (0.4%) were mixed infections with both norovirus GI and GII. Of the 147 vomiting only episodes, 30 (20.4%) were positive for norovirus in stool, of which 7 (4.8%) were norovirus GI and 23 (15.6%) GII. At least a third of the children developed norovirus associated diarrhea, with the first episode at a median age of 5 and 8 months for norovirus GI and GII, respectively. Norovirus GI.3 and GII.4 were the predominant genotypes (40.3% and 53.0%) with strain diversity and change in the predominant sub-cluster over time observed among GII viruses. A second episode of norovirus gastroenteritis was documented in 44/174 (25.3%) ever-infected children. Children with the G428A homozygous mutation for inactivation of the FUT2 enzyme (se428se428) were at a significantly lower risk (48/190) of infection with norovirus (p = 0.01). This is the first report of norovirus documenting disease, re-infection and genetic susceptibility in an Asian birth cohort. The high incidence and apparent lack of genogroupII specific immunity indicate the need for careful studies on further characterization of strains, asymptomatic infection and shedding and immune response to further our understanding of norovirus infection and disease.

  7. Impact of genotype-specific herd immunity on the circulatory dynamism of norovirus: a 10-year longitudinal study of viral acute gastroenteritis.

    PubMed

    Sakon, Naomi; Yamazaki, Kenji; Nakata, Keiko; Kanbayashi, Daiki; Yoda, Tomoko; Mantani, Masanobu; Kase, Tetsuo; Takahashi, Kazuo; Komano, Jun

    2015-03-15

    Human norovirus is a major cause of viral acute gastroenteritis worldwide. However, the transition of endemic norovirus genotypes remains poorly understood. The characteristics of natural immunity against norovirus are unclear because few studies have been performed in the natural infection setting. This prospective 10-year surveillance study of acute gastroenteritis in the province of Osaka, Japan, revealed that norovirus spread shows temporal, geographic, and age group-specific features in the humans. Genogroup II genotype 4 (GII.4) was detected in most sporadic pediatric cases, as well as in foodborne and nursing home outbreaks, respectively. The dominant genotypes in outbreaks at childcare facilities and schools shifted every season and involved GI, GII.2, GII.3, GII.4, and GII.6. Evidence at both the facility and individual levels indicated that genotype-specific herd immunity lasted long enough to influence the endemic norovirus genotype in the next season. Thus, norovirus circulates through human populations in a uniquely dynamic fashion.

  8. Llama Nanoantibodies with Therapeutic Potential against Human Norovirus Diarrhea

    PubMed Central

    Garaicoechea, Lorena; Aguilar, Andrea; Parra, Gabriel I.; Bok, Marina; Sosnovtsev, Stanislav V.; Canziani, Gabriela; Green, Kim Y.; Bok, Karin; Parreño, Viviana

    2015-01-01

    Noroviruses are a major cause of acute gastroenteritis, but no vaccines or therapeutic drugs are available. Llama-derived single chain antibody fragments (also called VHH) are small, recombinant monoclonal antibodies of 15 kDa with several advantages over conventional antibodies. The aim of this study was to generate recombinant monoclonal VHH specific for the two major norovirus (NoV) genogroups (GI and GII) in order to investigate their potential as immunotherapy for the treatment of NoV diarrhea. To accomplish this objective, two llamas were immunized with either GI.1 (Norwalk-1968) or GII.4 (MD2004) VLPs. After immunization, peripheral blood lymphocytes were collected and used to generate two VHH libraries. Using phage display technology, 10 VHH clones specific for GI.1, and 8 specific for GII.4 were selected for further characterization. All VHH recognized conformational epitopes in the P domain of the immunizing VP1 capsid protein, with the exception of one GII.4 VHH that recognized a linear P domain epitope. The GI.1 VHHs were highly specific for the immunizing GI.1 genotype, with only one VHH cross-reacting with GI.3 genotype. The GII.4 VHHs reacted with the immunizing GII.4 strain and showed a varying reactivity profile among different GII genotypes. One VHH specific for GI.1 and three specific for GII.4 could block the binding of homologous VLPs to synthetic HBGA carbohydrates, saliva, and pig gastric mucin, and in addition, could inhibit the hemagglutination of red blood cells by homologous VLPs. The ability of Nov-specific VHHs to perform well in these surrogate neutralization assays supports their further development as immunotherapy for NoV treatment and immunoprophylaxis. PMID:26267898

  9. Llama nanoantibodies with therapeutic potential against human norovirus diarrhea.

    PubMed

    Garaicoechea, Lorena; Aguilar, Andrea; Parra, Gabriel I; Bok, Marina; Sosnovtsev, Stanislav V; Canziani, Gabriela; Green, Kim Y; Bok, Karin; Parreño, Viviana

    2015-01-01

    Noroviruses are a major cause of acute gastroenteritis, but no vaccines or therapeutic drugs are available. Llama-derived single chain antibody fragments (also called VHH) are small, recombinant monoclonal antibodies of 15 kDa with several advantages over conventional antibodies. The aim of this study was to generate recombinant monoclonal VHH specific for the two major norovirus (NoV) genogroups (GI and GII) in order to investigate their potential as immunotherapy for the treatment of NoV diarrhea. To accomplish this objective, two llamas were immunized with either GI.1 (Norwalk-1968) or GII.4 (MD2004) VLPs. After immunization, peripheral blood lymphocytes were collected and used to generate two VHH libraries. Using phage display technology, 10 VHH clones specific for GI.1, and 8 specific for GII.4 were selected for further characterization. All VHH recognized conformational epitopes in the P domain of the immunizing VP1 capsid protein, with the exception of one GII.4 VHH that recognized a linear P domain epitope. The GI.1 VHHs were highly specific for the immunizing GI.1 genotype, with only one VHH cross-reacting with GI.3 genotype. The GII.4 VHHs reacted with the immunizing GII.4 strain and showed a varying reactivity profile among different GII genotypes. One VHH specific for GI.1 and three specific for GII.4 could block the binding of homologous VLPs to synthetic HBGA carbohydrates, saliva, and pig gastric mucin, and in addition, could inhibit the hemagglutination of red blood cells by homologous VLPs. The ability of Nov-specific VHHs to perform well in these surrogate neutralization assays supports their further development as immunotherapy for NoV treatment and immunoprophylaxis.

  10. Norovirus GII.17 as Major Epidemic Strain in Italy, Winter 2015–16

    PubMed Central

    De Grazia, Simona; Bonura, Floriana; Cappa, Vincenzo; Muli, Sara Li; Pepe, Arcangelo; Medici, Maria Cristina; Tummolo, Fabio; Calderaro, Adriana; Di Bernardo, Francesca; Dones, Piera; Morea, Anna; Loconsole, Daniela; Catella, Cristiana; Terio, Valentina; Bànyai, Krisztiàn; Chironna, Maria; Martella, Vito

    2017-01-01

    In winter 2015–16, norovirus GII.17 Kawasaki 2014 emerged as a cause of sporadic gastroenteritis in children in Italy. Median patient age was higher for those with GII.17 than GII.4 infection (55 vs. 24 months), suggesting limited cross-protection for older children. PMID:28628440

  11. Inactivation of human norovirus in contaminated oysters and clams by high-hydrostatic pressure

    USDA-ARS?s Scientific Manuscript database

    Human norovirus (NoV) is the most frequent causative agent of foodborne disease associated with shellfish consumption. In this study, the effect of high-hydrostatic pressure (HHP) on inactivation of NoV was determined. Genogroup I.1 (GI.1) or Genogroup II.4 (GII.4) NoV were inoculated into oyster ho...

  12. A decade of norovirus genetic diversity in Belgium.

    PubMed

    Wollants, Elke; De Coster, Sarah; Van Ranst, Marc; Maes, Piet

    2015-03-01

    Outbreaks of norovirus-associated gastroenteritis occur during all seasons and in various locations, and are recognized as one of the most common causes of nonbacterial food-borne infections. The molecular epidemiology of norovirus infections has not been well characterized in Belgium. To study the incidence of norovirus infections and the nature of the circulating genotypes, 3080 specimens were collected from patients with acute gastroenteritis between 2004 and 2014. Norovirus was detected with RT-PCR in 554 samples (18%). The circulating strains were genotyped based on the variability in the 5' end of the capsid gene (region C). The GII.4 genotype, which is detected predominantly worldwide, was also the most prevalent genotype in our study (87%). This study shows a high frequency and genetic diversity of norovirus in patients with acute gastroenteritis in health care facilities in Flanders, Belgium. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Rapid emergence and predominance of a broadly recognizing and fast-evolving norovirus GII.17 variant in late 2014

    PubMed Central

    Chan, Martin C. W.; Lee, Nelson; Hung, Tin-Nok; Kwok, Kirsty; Cheung, Kelton; Tin, Edith K. Y.; Lai, Raymond W. M.; Nelson, E. Anthony S.; Leung, Ting F.; Chan, Paul K. S.

    2015-01-01

    Norovirus genogroup II genotype 4 (GII.4) has been the predominant cause of viral gastroenteritis since 1996. Here we show that during the winter of 2014–2015, an emergent variant of a previously rare norovirus GII.17 genotype, Kawasaki 2014, predominated in Hong Kong and outcompeted contemporary GII.4 Sydney 2012 in hospitalized cases. GII.17 cases were significantly older than GII.4 cases. Root-to-tip and Bayesian BEAST analyses estimate GII.17 viral protein 1 (VP1) evolves one order of magnitude faster than GII.4 VP1. Residue substitutions and insertion occur in four of five inferred antigenic epitopes, suggesting immune evasion. Sequential GII.4-GII.17 infections are noted, implicating a lack of cross-protection. Virus bound to saliva of secretor histo-blood groups A, B and O, indicating broad susceptibility. This fast-evolving, broadly recognizing and probably immune-escaped emergent GII.17 variant causes severe gastroenteritis and hospitalization across all age groups, including populations who were previously less vulnerable to GII.4 variants; therefore, the global spread of GII.17 Kawasaki 2014 needs to be monitored. PMID:26625712

  14. Adsorption and Aggregation Properties of Norovirus GI and GII Virus-like Particles Demonstrate Differing Responses to Solution Chemistry

    PubMed Central

    DA SILVA, ALLEGRA K.; KAVANAGH, OWEN V.; ESTES, MARY K.; ELIMELECH, MENACHEM

    2014-01-01

    The transport properties (adsorption and aggregation behavior) of virus-like particles (VLPs) of two strains of norovirus (“Norwalk” GI.1 and “Houston” GII.4) were studied in a variety of solution chemistries. GI.1 and GII.4 VLPs were found to be stable against aggregation at pH 4.0–8.0. At pH 9.0, GI.1 VLPs rapidly disintegrated. The attachment efficiencies (α) of GI.1 and GII.4 VLPs to silica increased with increasing ionic strength in NaCl solutions at pH 8.0. The attachment efficiency of GI.1 VLPs decreased as pH was increased above the isoelectric point (pH 5.0), whereas at and below the isoelectric point, the attachment efficiency was erratic. Ca2+ and Mg2+ dramatically increased the attachment efficiencies of GI.1 and GII.4 VLPs, which may be due to specific interactions with the VLP capsids. Bicarbonate decreased attachment efficiencies for both GI.1 and GII.4 VLPs, whereas phosphate decreased the attachment efficiency of GI.1, while increasing GII.4 attachment efficiency. The observed differences in GI.1 and GII.4 VLP attachment efficiencies in response to solution chemistry may be attributed to differential responses of the unique arrangement of exposed amino acid residues on the capsid surface of each VLP strain. PMID:21121659

  15. Human Norovirus Evolution in a Chronically Infected Host

    PubMed Central

    Doerflinger, Sylvie Y.; Weichert, Stefan; Koromyslova, Anna; Chan, Martin; Schwerk, Christian; Adam, Ruediger; Jennewein, Stefan

    2017-01-01

    ABSTRACT Typically, human noroviruses cause symptoms of acute gastroenteritis for 2 to 4 days. Often, the virions are shed in stool for several days after the symptoms recede, which in turn can lead to further contamination and transmission. Moreover, a number of reports have considered that chronic norovirus infections, i.e., lasting months and years, might even function as reservoirs for the generation of novel strains that can escape the herd immunity or have modified binding interactions with histo-blood group antigens (HBGAs). In this study, we analyzed noroviruses isolated from a patient who has presented a chronic infection for more than 6 years. We found that the isolated capsid sequences clustered into two main genetic types (termed A and B), despite a plethora of capsid quasi-sequences. Furthermore, the two genetic types corresponded well with distinct antigenicities. On the other hand, we showed that numerous amino acid substitutions on the capsid surface of genetic types A and B did not alter the HBGA binding profiles. However, divergent binding profiles for types A and B were observed with human milk oligosaccharides (HMOs), which structurally mimic HBGAs and may act as natural antivirals. Importantly, the isolated capsid sequences only had approximately 90% amino acid identity with other known sequences, which suggested that transmission of these chronic noroviruses could be limited. IMPORTANCE The norovirus genogroup II genotype 4 (GII.4) variants have approximately 5% divergence in capsid amino acid identity and have dominated over the past decade. The precise reason(s) for the GII.4 emergence and persistence in the human population is still unknown, but some studies have suggested that chronically infected patients might generate novel variants that can cause new epidemics. We examined GII.4 noroviruses isolated from an immunocompromised patient with a long-term infection. Numerous norovirus capsid quasi-species were isolated during the 13-month

  16. Innate Susceptibility to Norovirus Infections Influenced by FUT2 Genotype in a United States Pediatric Population

    PubMed Central

    Currier, Rebecca L.; Payne, Daniel C.; Staat, Mary A.; Selvarangan, Rangaraj; Shirley, S. Hannah; Halasa, Natasha; Boom, Julie A.; Englund, Janet A.; Szilagyi, Peter G.; Harrison, Christopher J.; Klein, Eileen J.; Weinberg, Geoffrey A.; Wikswo, Mary E.; Parashar, Umesh; Vinjé, Jan; Morrow, Ardythe L.

    2015-01-01

    Background. Norovirus is a leading cause of acute gastroenteritis (AGE). Noroviruses bind to gut histo-blood group antigens (HBGAs), but only 70%–80% of individuals have a functional copy of the FUT2 (“secretor”) gene required for gut HBGA expression; these individuals are known as “secretors.” Susceptibility to some noroviruses depends on FUT2 secretor status, but the population impact of this association is not established. Methods. From December 2011 to November 2012, active AGE surveillance was performed at 6 geographically diverse pediatric sites in the United States. Case patients aged <5 years were recruited from emergency departments and inpatient units; age-matched healthy controls were recruited at well-child visits. Salivary DNA was collected to determine secretor status and genetic ancestry. Stool was tested for norovirus by real-time reverse transcription polymerase chain reaction. Norovirus genotype was then determined by sequencing. Results. Norovirus was detected in 302 of 1465 (21%) AGE cases and 52 of 826 (6%) healthy controls. Norovirus AGE cases were 2.8-fold more likely than norovirus-negative controls to be secretors (P < .001) in a logistic regression model adjusted for ancestry, age, site, and health insurance. Secretors comprised all 155 cases and 21 asymptomatic infections with the most prevalent norovirus, GII.4. Control children of Meso-American ancestry were more likely than children of European or African ancestry to be secretors (96% vs 74%; P < .001). Conclusions. FUT2 status is associated with norovirus infection and varies by ancestry. GII.4 norovirus exclusively infected secretors. These findings are important to norovirus vaccine trials and design of agents that may block norovirus-HBGA binding. PMID:25744498

  17. Innate Susceptibility to Norovirus Infections Influenced by FUT2 Genotype in a United States Pediatric Population.

    PubMed

    Currier, Rebecca L; Payne, Daniel C; Staat, Mary A; Selvarangan, Rangaraj; Shirley, S Hannah; Halasa, Natasha; Boom, Julie A; Englund, Janet A; Szilagyi, Peter G; Harrison, Christopher J; Klein, Eileen J; Weinberg, Geoffrey A; Wikswo, Mary E; Parashar, Umesh; Vinjé, Jan; Morrow, Ardythe L

    2015-06-01

    Norovirus is a leading cause of acute gastroenteritis (AGE). Noroviruses bind to gut histo-blood group antigens (HBGAs), but only 70%-80% of individuals have a functional copy of the FUT2 ("secretor") gene required for gut HBGA expression; these individuals are known as "secretors." Susceptibility to some noroviruses depends on FUT2 secretor status, but the population impact of this association is not established. From December 2011 to November 2012, active AGE surveillance was performed at 6 geographically diverse pediatric sites in the United States. Case patients aged <5 years were recruited from emergency departments and inpatient units; age-matched healthy controls were recruited at well-child visits. Salivary DNA was collected to determine secretor status and genetic ancestry. Stool was tested for norovirus by real-time reverse transcription polymerase chain reaction. Norovirus genotype was then determined by sequencing. Norovirus was detected in 302 of 1465 (21%) AGE cases and 52 of 826 (6%) healthy controls. Norovirus AGE cases were 2.8-fold more likely than norovirus-negative controls to be secretors (P < .001) in a logistic regression model adjusted for ancestry, age, site, and health insurance. Secretors comprised all 155 cases and 21 asymptomatic infections with the most prevalent norovirus, GII.4. Control children of Meso-American ancestry were more likely than children of European or African ancestry to be secretors (96% vs 74%; P < .001). FUT2 status is associated with norovirus infection and varies by ancestry. GII.4 norovirus exclusively infected secretors. These findings are important to norovirus vaccine trials and design of agents that may block norovirus-HBGA binding. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Burden of Norovirus and Rotavirus in Children after Rotavirus Vaccine Introduction, Cochabamba, Bolivia

    PubMed Central

    McAtee, Casey L.; Webman, Rachel; Gilman, Robert H.; Mejia, Carolina; Bern, Caryn; Apaza, Sonia; Espetia, Susan; Pajuelo, Mónica; Saito, Mayuko; Challappa, Roxanna; Soria, Richard; Ribera, Jose P.; Lozano, Daniel; Torrico, Faustino

    2016-01-01

    The effectiveness of rotavirus vaccine in the field may set the stage for a changing landscape of diarrheal illness affecting children worldwide. Norovirus and rotavirus are the two major viral enteropathogens of childhood. This study describes the prevalence of norovirus and rotavirus 2 years after widespread rotavirus vaccination in Cochabamba, Bolivia. Stool samples from hospitalized children with acute gastroenteritis (AGE) and outpatients aged 5–24 months without AGE were recruited from an urban hospital serving Bolivia's third largest city. Both viruses were genotyped, and norovirus GII.4 was further sequenced. Norovirus was found much more frequently than rotavirus. Norovirus was detected in 69/201 (34.3%) of specimens from children with AGE and 13/71 (18.3%) of those without diarrhea. Rotavirus was detected in 38/201 (18.9%) of diarrheal specimens and 3/71 (4.2%) of non-diarrheal specimens. Norovirus GII was identified in 97.8% of norovirus-positive samples; GII.4 was the most common genotype (71.4% of typed specimens). Rotavirus G3P[8] was the most prevalent rotavirus genotype (44.0% of typed specimens) and G2P[4] was second most prevalent (16.0% of typed specimens). This community is likely part of a trend toward norovirus predominance over rotavirus in children after widespread vaccination against rotavirus. PMID:26598569

  19. Burden of Norovirus and Rotavirus in Children After Rotavirus Vaccine Introduction, Cochabamba, Bolivia.

    PubMed

    McAtee, Casey L; Webman, Rachel; Gilman, Robert H; Mejia, Carolina; Bern, Caryn; Apaza, Sonia; Espetia, Susan; Pajuelo, Mónica; Saito, Mayuko; Challappa, Roxanna; Soria, Richard; Ribera, Jose P; Lozano, Daniel; Torrico, Faustino

    2016-01-01

    The effectiveness of rotavirus vaccine in the field may set the stage for a changing landscape of diarrheal illness affecting children worldwide. Norovirus and rotavirus are the two major viral enteropathogens of childhood. This study describes the prevalence of norovirus and rotavirus 2 years after widespread rotavirus vaccination in Cochabamba, Bolivia. Stool samples from hospitalized children with acute gastroenteritis (AGE) and outpatients aged 5-24 months without AGE were recruited from an urban hospital serving Bolivia's third largest city. Both viruses were genotyped, and norovirus GII.4 was further sequenced. Norovirus was found much more frequently than rotavirus. Norovirus was detected in 69/201 (34.3%) of specimens from children with AGE and 13/71 (18.3%) of those without diarrhea. Rotavirus was detected in 38/201 (18.9%) of diarrheal specimens and 3/71 (4.2%) of non-diarrheal specimens. Norovirus GII was identified in 97.8% of norovirus-positive samples; GII.4 was the most common genotype (71.4% of typed specimens). Rotavirus G3P[8] was the most prevalent rotavirus genotype (44.0% of typed specimens) and G2P[4] was second most prevalent (16.0% of typed specimens). This community is likely part of a trend toward norovirus predominance over rotavirus in children after widespread vaccination against rotavirus. © The American Society of Tropical Medicine and Hygiene.

  20. Genetic diversity and distribution of human norovirus in China (1999-2011).

    PubMed

    Yu, Yongxin; Yan, Shuling; Li, Bailin; Pan, Yingjie; Wang, Yongjie

    2014-01-01

    Noroviruses (NoVs) are a leading cause of epidemic and sporadic acute gastroenteritis worldwide. However, the genetic diversity and geographical distribution of NoV isolates from China have not been well described thus far. In this study, all NoV sequences obtained in China from 1999 to 2011 (n = 983), both partial and complete genomes, were downloaded from GenBank. Genotyping and phylogenetic and recombination analyses were performed in order to gain a better understanding of the distribution and genetic diversity of NoVs in China. The results indicated that approximately 90% of NoV sequences were obtained from the coastal regions of China, and most of the NoV sequences from distinct geographical regions appeared to be closely related. GII.4 was the most prevalent genotype, accounting for 64.4% of all genotypes, followed by GII.12 (13.9%) and GII.3 (7.0%). Over the last decade, the GII.4 variants were dominated by successive circulation of GII.4/2002, GII.4/2004, GII.4/2006b, and GII.4/2008, with GII.4/2006b continuing to date. A relatively high frequency of NoV intergenotype recombinants was identified. The most common ORF1/ORF2 intergenotype recombinant was GII.12/GII.4 (n = 11), and the relative frequency was up to 30% among all the recombinant strains (n = 36). These findings may aid in the evaluation and implementation of appropriate measures for monitoring NoV infectious diseases in China.

  1. Evaluation of chlorine treatment levels on inactivation of human norovirus and MS2 bacteriophage during sewage treatment

    USDA-ARS?s Scientific Manuscript database

    This study examined the inactivation of human norovirus (HuNoV) GI.1 and GII.4 by chlorine under conditions that mimic sewage treatment. Using a porcine gastric mucin-magnetic bead (PGM-MB) assay, no statistically significant loss in HuNoV binding (inactivation) was observed for secondary effluent ...

  2. Virus Genotype Distribution and Virus Burden in Children and Adults Hospitalized for Norovirus Gastroenteritis, 2012–2014, Hong Kong

    PubMed Central

    Chan, Martin C.W.; Leung, Ting F.; Chung, Tracy W.S.; Kwok, Angela K.; Nelson, E. Anthony S.; Lee, Nelson; Chan, Paul K.S.

    2015-01-01

    We conducted a 2-year hospital-based study on norovirus gastroenteritis among children and adults between August 2012 and September 2014. A total of 1,146 norovirus cases were identified. Young children (aged ≤ 5 years) accounted for a majority (53.3%) of cases. Hospitalization incidence exhibited a U-shaped pattern with the highest rate in young children (1,475 per 100,000 person-years), followed by the elderly aged > 84 years (581 per 100,000 person-years). A subset (n = 395, 34.5%) of cases were selected for norovirus genotyping and noroviral load measurement. Non-GII.4 infections were more commonly observed in young children than in older adults (aged > 65 years) (20.5% versus 9.2%; p < 0.05). In young children, the median noroviral load of GII.4 and non-GII.4 cases was indistinguishably high (cycle threshold value, median [interquartile range]: 16.6 [15.2–19.3] versus 16.6 [14.9–21.6]; p = 0.45). Two age-specific non-GII.4 genotypes (GII.3 and GII.6) were identified among young children. These findings may have implications in norovirus vaccination strategy. PMID:26082165

  3. Virus Genotype Distribution and Virus Burden in Children and Adults Hospitalized for Norovirus Gastroenteritis, 2012-2014, Hong Kong.

    PubMed

    Chan, Martin C W; Leung, Ting F; Chung, Tracy W S; Kwok, Angela K; Nelson, E Anthony S; Lee, Nelson; Chan, Paul K S

    2015-06-17

    We conducted a 2-year hospital-based study on norovirus gastroenteritis among children and adults between August 2012 and September 2014. A total of 1,146 norovirus cases were identified. Young children (aged ≤ 5 years) accounted for a majority (53.3%) of cases. Hospitalization incidence exhibited a U-shaped pattern with the highest rate in young children (1,475 per 100,000 person-years), followed by the elderly aged > 84 years (581 per 100,000 person-years). A subset (n = 395, 34.5%) of cases were selected for norovirus genotyping and noroviral load measurement. Non-GII.4 infections were more commonly observed in young children than in older adults (aged > 65 years) (20.5% versus 9.2%; p < 0.05). In young children, the median noroviral load of GII.4 and non-GII.4 cases was indistinguishably high (cycle threshold value, median [interquartile range]: 16.6 [15.2-19.3] versus 16.6 [14.9-21.6]; p = 0.45). Two age-specific non-GII.4 genotypes (GII.3 and GII.6) were identified among young children. These findings may have implications in norovirus vaccination strategy.

  4. Molecular characteristics of noroviruses genogroup I and genogroup II detected in patients with acute gastroenteritis.

    PubMed

    Ham, Heejin; Oh, Seah; Seung, Hyunjung; Jo, Sukju

    2015-03-01

    Noroviruses are the leading cause of epidemic gastroenteritis, including foodborne outbreak, in Korea. The prevalence of human noroviruses was studied in diarrheal stool samples of patients with acute gastroenteritis by conventional duplex reverse transcription (RT)-PCR. Diarrheal stool samples were collected from 1,685 patients from the local hospitals in Seoul. The prevalence of the noroviruses was 22.8% (222/972 patients) in 2012 and 11.2% (80/713 patients) in 2013, with a total of 17.9% (302/1,685 patients). Genotyping was performed on 302 norovirus-positive stool samples to reveal 5.6% prevalence of genogroup I (GI) (17/302) and 94.4% prevalence of genogroup II (GII) (285/302). The patients with norovirus-associated acute gastroenteritis mostly showed prevalence of GII norovirus, especially GII.4 (64.6%; 195/302).

  5. Variant-specific prion interactions

    PubMed Central

    Sharma, Jaya; Liebman, Susan W

    2013-01-01

    Prions are protein conformations that “self-seed” the misfolding of their non-prion iso-forms into prion, often amyloid, conformations. The most famous prion is the mammalian PrP protein that in its prion form causes transmissible spongiform encephalopathy. Curiously there can be distinct conformational differences even between prions of the same protein propagated in the same host species. These are called prion strains or variants. For example, different PrP variants are faithfully transmitted during self-seeding and are associated with distinct disease characteristics. Variant-specific PrP prion differences include the length of the incubation period before the disease appears and the deposition of prion aggregates in distinct regions of the brain.1 Other more common neurodegenerative diseases (e.g., Alzheimer disease, Parkinson disease, type 2 diabetes and ALS) are likewise caused by the misfolding of a normal protein into a self-seeding aggregate.2-4 One of the most important unanswered questions is how the first prion-like seed arises de novo, resulting in the pathological cascade. PMID:24475372

  6. Preclinical Dose Ranging Studies of a Novel Dry Powder Norovirus Vaccine Formulation

    PubMed Central

    Springer, Michael J.; Ni, Yawei; Finger-Baker, Isaac; Ball, Jordan P.; Hahn, Jessica; DiMarco, Ashley V.; Kobs, Dean; Horne, Bobbi; Talton, James D.; Cobb, Ronald R.

    2016-01-01

    Norovirus is the primary cause of viral gastroenteritis in humans with multiple genotypes currently circulating worldwide. The development of a successful norovirus vaccine is contingent on its ability to induce both systemic and mucosal antibody responses against a wide range of norovirus genotypes. Norovirus virus like particles (VLPs) are known to elicit systemic and mucosal immune responses when delivered intranasally. Incorporation of these VLPs into an intranasal powder vaccine offers the advantage of simplicity and induction of neutralizing systemic and mucosal antibodies. Nasal immunization, which provides the advantage of ease of administration and a mucosal delivery mechanism, faces the real issue of limited nasal residence time due to mucociliary clearance. Herein, we describe a novel dry powder (GelVac™) formulation of GI or GII.4 norovirus VLPs, two dominant circulating genotypes, to identify the optimal antigen dosages based on systemic and mucosal immune responses in guinea pigs. Systemic and mucosal immunogenicity of each of the VLPs was observed in a dose dependant manner. In addition, a boosting effect was observed after the second dosing of each VLP antigen. With the GelVac™ formulation, a total antigen dose of ≥15 µg was determined to be the maximally immunogenic dose for both GI and GII.4 norovirus VLP based on evaluation for 56 days. Taken together, these results indicate that norovirus VLPs could be used as potential vaccine candidates without using an immunostimilatory adjuvant and provides a basis for the development of a GelVac™ bivalent GI/GII.4 norovirus VLP vaccine. PMID:26873053

  7. Norovirus Infection

    MedlinePlus

    ... has a norovirus infection Noroviruses are difficult to wipe out because they can withstand hot and cold ... especially after using the toilet or changing a diaper. Avoid contaminated food and water, including food that ...

  8. Molecular characterization of norovirus variants and genetic diversity of noroviruses and sapoviruses in Thailand.

    PubMed

    Chaimongkol, Natthawan; Khamrin, Pattara; Malasao, Rungnapa; Thongprachum, Aksara; Kongsricharoern, Tipachan; Ukarapol, Nuthapong; Ushijima, Hiroshi; Maneekarn, Niwat

    2014-07-01

    Norovirus (NoV) and Sapovirus (SaV) have been reported as a common cause of acute gastroenteritis worldwide. For a decade, surveillances of NoV and SaV have been conducted continually in Thailand. To monitor the epidemiological situation and to determine the genetic variation of NoV and SaV in Chiang Mai, Thailand, 567 samples collected from pediatric patients hospitalized with acute gastroenteritis were examined during 2007, and 2010-2011 by semi-nested RT-PCR and nucleotide sequencing methods. NoV was detected at 15.9%. Phylogenetic analysis revealed multiple NoV genotypes, GI/14 (1.1%), GII/1 (1.1%), GII/2 (1.1%), GII/3 (4.4%), GII/4 (65.6%), GII/6 (10.0%), GII/7 (2.2%), GII/12 (4.4%), GII/13 (3.3%), GII/16 (5.7%), and unclassified genotype (1.1%), circulating in this area. Among these, NoV GII/4 was the most prevalent genotype with a predominance of GII/4 2009 over other variants, 1996, 2006a, and 2006b. For SaV, the prevalence was 1.2% which was much lower than those of NoV and only SaV GI/1 was detected. This study highlights the epidemiology of NoV and SaV and genetic diversity of viruses circulating in pediatric patients hospitalized with acute gastroenteritis in Chiang Mai, Thailand.

  9. Identification of human single-chain antibodies with broad reactivity for noroviruses

    PubMed Central

    Huang, Wanzhi; Samanta, Moumita; Crawford, Sue E.; Estes, Mary K.; Neill, Frederick H.; Atmar, Robert L.; Palzkill, Timothy

    2014-01-01

    Norovirus infections are a common cause of gastroenteritis and new methods to rapidly diagnose norovirus infections are needed. The goal of this study was to identify antibodies that have broad reactivity of binding to various genogroups of norovirus. A human scFv phage display library was used to identify two antibodies, HJT-R3-A9 and HJT-R3-F7, which bind to both genogroups I and II norovirus virus-like particles (VLPs). Mapping experiments indicated that the HJT-R3-A9 clone binds to the S-domain while the HJT-R3-F7 clone binds the P-domain of the VP1 capsid protein. In addition, a family of scFv antibodies was identified by elution of phage libraries from the GII.4 VLP target using a carbohydrate that serves as an attachment factor for norovirus on human cells. These antibodies were also found to recognize both GI and GII VLPs in enzyme-linked immunosorbent assay (ELISA) experiments. The HJT-R3-A9, HJT-R3-F7 and scFv antibodies identified with carbohydrate elution were shown to detect antigen from a clinical sample known to contain GII.4 norovirus but not a negative control sample. Finally, phages displaying the HJT-R3-A9 scFv can be used directly to detect both GI.1 and GII.4 norovirus from stool samples, which has the potential to simplify and reduce the cost of diagnostics based on antibody-based ELISA methods. PMID:24946948

  10. Distribution of Human Norovirus in the Coastal Waters of South Korea

    PubMed Central

    Choi, Yong Seon; Kim, Ji Young; Yoo, Chang Hoon; Yoon, Hyun Jin; Kim, Tae-Ok; Choi, Hyun Bae; Kim, Ji Hoon; Choi, Jong Deok; Park, Kwon-Sam; Shin, Yongsik; Kim, Young-Mog; Ko, GwangPyo; Jeong, Yong Seok

    2016-01-01

    The presence of human norovirus in the aquatic environment can cause outbreaks related to recreational activities and the consumption of norovirus-contaminated clams. In this study, we investigated the prevalence of norovirus genogroups I (GI) and II (GII) in the coastal aquatic environment in South Korea (March 2014 to February 2015). A total of 504 water samples were collected periodically from four coastal areas (total sites = 63), of which 44 sites were in estuaries (clam fisheries) and 19 were in inflow streams. RT-PCR analysis targeting ORF2 region C revealed that 20.6% of the water samples were contaminated by GI (13.3%) or GII (16.6%). The prevalence of human norovirus was higher in winter/spring than in summer/fall, and higher in inflow streams (50.0%) than in estuaries (7.9%). A total of 229 human norovirus sequences were identified from the water samples, and phylogenetic analysis showed that the sequences clustered into eight GI genotypes (GI.1, 2, 3, 4, 5, 6, 7, and 9) and nine GII genotypes (GII.2, 3, 4, 5, 6, 11, 13, 17, and 21). This study highlighted three issues: 1) a strong correlation between norovirus contamination via inflow streams and coastal areas used in clam fisheries; 2) increased prevalence of certain non-GII.4 genotypes, exceeding that of the GII.4 pandemic variants; 3) seasonal shifts in the dominant genotypes of both GI and GII. PMID:27681683

  11. Norovirus Recombinant Strains Isolated from Gastroenteritis Outbreaks in Southern Brazil, 2004–2011

    PubMed Central

    Leite, José Paulo Gagliardi; Miagostovich, Marize Pereira

    2016-01-01

    Noroviruses are recognized as one of the leading causes of viral acute gastroenteritis, responsible for almost 50% of acute gastroenteritis outbreaks worldwide. The positive single-strand RNA genome of noroviruses presents a high mutation rate and these viruses are constantly evolving by nucleotide mutation and genome recombination. Norovirus recombinant strains have been detected as causing acute gastroenteritis outbreaks in several countries. However, in Brazil, only one report of a norovirus recombinant strain (GII.P7/GII.20) has been described in the northern region so far. For this study, 38 norovirus strains representative of outbreaks, 11 GII.4 and 27 non-GII.4, were randomly selected and amplified at the ORF1/ORF2 junction. Genetic recombination was identified by constructing phylogenetic trees of the polymerase and capsid genes, and further SimPlot and Bootscan analysis of the ORF1/ORF2 overlap. Sequence analysis revealed that 23 out of 27 (85%) non-GII.4 noroviruses were recombinant strains, characterized as: GII.P7/GII.6 (n = 9); GIIP.g/GII.12 (n = 4); GII.P16/GII.3 (n = 4); GII.Pe/GII.17 (n = 2); GII.P7/GII.14 (n = 1); GII.P13/GII.17 (n = 1); GII.P21/GII.3 (n = 1); and GII.P21/GII.13 (n = 1). On the other hand, among the GII.4 variants analyzed (Den Haag_2006b and New Orleans_2009) no recombination was observed. These data revealed the great diversity of norovirus recombinant strains associated with outbreaks, and describe for the first time these recombinant types circulating in Brazil. Our results obtained in southern Brazil corroborate the previous report for the northern region, demonstrating that norovirus recombinant strains are circulating more frequently than we expected. In addition, these results emphasize the relevance of including ORF1/ORF2-based analysis in surveillance studies as well as the importance of characterizing strains from other Brazilian regions to obtain epidemiological data for norovirus recombinant strains circulating in the

  12. Molecular epidemiology of norovirus in children and the elderly in Atlanta, Georgia, United States.

    PubMed

    Yi, Jumi; Wahl, Kelly; Sederdahl, Bethany K; Jerris, Robert R; Kraft, Colleen S; McCracken, Courtney; Gillespie, Scott; Anderson, Evan J; Kirby, Amy E; Shane, Andi L; Moe, Christine L

    2016-06-01

    Noroviruses are an important cause of gastroenteritis, which can be severe at the extremes of ages. Data documenting the endemic burden of norovirus among children and elderly adults are lacking. Stool specimens submitted for clinical testing were collected from elderly (≥ 65 years) adults and children (<18 years) with acute vomiting and/or diarrhea seeking care at several metropolitan Atlanta adult and pediatric hospitals from January 2013-June 2013. Specimens were tested for norovirus with real-time RT-PCR and sequenced if norovirus was detected. Corresponding clinical and demographic data were abstracted from retrospective chart review. Norovirus was detected in 11% (11/104) of elderly specimens and 11% (67/628) of pediatric, with GII.4 Sydney_2012 detected in 64% (7/11) of elderly norovirus-positive and 11% (8/67) of pediatric specimens, P < 0.001. In comparison to hospitalized children, hospitalized elderly with norovirus were more commonly admitted to the intensive care unit (ICU) (36% vs. 7%, P = 0.02). Norovirus in the elderly can be associated with severe illness requiring ICU admissions. The pediatric group demonstrated greater variability in genotype distribution. Ongoing surveillance of norovirus genotypes is crucial for norovirus vaccine development in understanding circulating and emerging genotypes.

  13. First norovirus outbreaks associated with consumption of green seaweed (Enteromorpha spp.) in South Korea.

    PubMed

    Park, J H; Jeong, H S; Lee, J S; Lee, S W; Choi, Y H; Choi, S J; Joo, I S; Kim, Y R; Park, Y K; Youn, S K

    2015-02-01

    In February 2012, an outbreak of gastroenteritis was reported in school A; a successive outbreak was reported at school B. A retrospective cohort study conducted in school A showed that seasoned green seaweed with radishes (relative risk 7·9, 95% confidence interval 1·1-56·2) was significantly associated with illness. Similarly, a case-control study of students at school B showed that cases were 5·1 (95% confidence interval 1·1-24·8) times more likely to have eaten seasoned green seaweed with pears. Multiple norovirus genotypes were detected in samples from students in schools A and B. Norovirus GII.6 isolated from schools A and B were phylogenetically indistinguishable. Green seaweed was supplied by company X, and norovirus GII.4 was isolated from samples of green seaweed. Green seaweed was assumed to be linked to these outbreaks. To our knowledge, this is the first reported norovirus outbreak associated with green seaweed.

  14. Norovirus Symptoms

    MedlinePlus

    ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology Symptoms Language: English Español (Spanish) Recommend on Facebook ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology Language: English Español (Spanish) File Formats Help: How ...

  15. Norovirus Treatment

    MedlinePlus

    ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology Treatment Language: English Español (Spanish) Recommend on Facebook ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology Language: English Español (Spanish) File Formats Help: How ...

  16. Evolutionary Phylodynamics of Korean Noroviruses Reveals a Novel GII.2/GII.10 Recombination Event

    PubMed Central

    Truong, Thoi Cong; Than, Van Thai; Kim, Wonyong

    2014-01-01

    Viral gastroenteritis is the most common causal agent of public health problems worldwide. Noroviruses cause nonbacterial acute gastroenteritis in humans of all ages. In this study, we investigated the occurrence of norovirus infection in children with acute gastroenteritis admitted to university hospitals in South Korea. We also analyzed the genetic diversity of the viruses and identified novel recombination events among the identified viral strains. Of 502 children with acute gastroenteritis admitted to our three hospitals between January 2011 and March 2012, genotyping of human noroviruses was performed in 171 (34%) norovirus-positive samples. Of these samples, 170 (99.5%) were in genogroup II (GII), while only one (0.5%) was in genogroup I (GI). The most common GII strain was the GII.4-2006b variant (n = 96, 56.5%), followed by GII.6 (n = 23, 13.5%), GII.12 (n = 22, 12.9%), GII.3 (n = 20, 11.8%), GII.2 (n = 6, 3.5%), GII.b (n = 2, 1.2%), and GII.10 (n = 1, 0.6%). Potential recombination events (polymerase/capsid) were detected in 39 GII strains (22.9%), and the most frequent genotypes were GII.4/GII.12 (n = 12, 30.8%), GII.4/GII.6 (n = 12, 30.8%), GII.4/GII.3 (n = 8, 20.5%), GII.b/GII.3 (n = 3, 7.7%), GII.16/GII.2 (n = 2, 5.1%), GII.4/GII.2 (n = 1, 2.6%), and GII.2/GII.10 (n = 1, 2.6%). For the first time, a novel GII.2/GII.10 recombination was detected; we also identified the GII.16/GII.2 strain for the first time in South Korea. Our data provided important insights into new recombination events, which may prove valuable for predicting the emergence of circulating norovirus strains with global epidemic potential. PMID:25500567

  17. Prevalence and Molecular Genotyping of Noroviruses in Market Oysters, Mussels, and Cockles in Bangkok, Thailand.

    PubMed

    Kittigul, Leera; Thamjaroen, Anyarat; Chiawchan, Suwat; Chavalitshewinkoon-Petmitr, Porntip; Pombubpa, Kannika; Diraphat, Pornphan

    2016-06-01

    Noroviruses are the most common cause of acute gastroenteritis associated with bivalve shellfish consumption. This study aimed to detect and characterize noroviruses in three bivalve shellfish species: oysters (Saccostrea forskali), cockles (Anadara nodifera), and mussels (Perna viridis). The virus concentration procedure (adsorption-twice elution-extraction) and a molecular method were employed to identify noroviruses in shellfish. RT-nested PCR was able to detect known norovirus GII.4 of 8.8 × 10(-2) genome copies/g of digestive tissues from oyster and cockle concentrates, whereas in mussel concentrates, the positive result was seen at 8.8 × 10(2) copies/g of digestive tissues. From August 2011 to July 2012, a total of 300 shellfish samples, including each of 100 samples from oysters, cockles, and mussels were collected and tested for noroviruses. Norovirus RNA was detected in 12.3 % of shellfish samples. Of the noroviruses, 7.7 % were of the genogroup (G) I, 2.6 % GII, and 2.0 % were mixed GI and GII. The detection rate of norovirus GI was 2.1 times higher than GII. With regards to the different shellfish species, 17 % of the oyster samples were positive, while 14.0 and 6.0 % were positive for noroviruses found in mussels and cockles, respectively. Norovirus contamination in the shellfish occurred throughout the year with the highest peak in September. Seventeen norovirus-positive PCR products were characterized upon a partial sequence analysis of the capsid gene. Based on phylogenetic analysis, five different genotypes of norovirus GI (GI.2, GI.3, GI.4, GI.5, and GI.9) and four different genotypes of GII (GII.1, GII.2, GII.3, and GII.4) were identified. These findings indicate the prevalence and distribution of noroviruses in three shellfish species. The high prevalence of noroviruses in oysters contributes to the optimization of monitoring plans to improve the preventive strategies of acute gastroenteritis.

  18. Molecular Epidemiology and Genetic Diversity of Norovirus in Young Children in Phnom Penh, Cambodia

    PubMed Central

    Nakjarung, Kaewkanya; Neesanant, Pimmnapar; Lertsethtakarn, Paphavee; Sethabutr, Orntipa; Vansith, Ket; Meng, Chhour Y.; Swierczewski, Brett E.; Mason, Carl J.

    2016-01-01

    This study investigated the genetic diversity of noroviruses identified from a previous surveillance study conducted at the National Pediatric Hospital in Phnom Penh, Cambodia, from 2004 to 2006. In the previous study, 926 stool samples were collected from children aged 3–60 months with acute diarrhea (cases) and without diarrhea (controls) with reported 6.7% of cases and 3.2% of controls being positive for norovirus. The initial norovirus diagnostic assay was performed with real-time reverse transcription-polymerase chain reaction (real-time RT PCR) which also distinguished between genogroups I and II (GI and GII). Norovirus infection was most commonly detected in children aged 12–23 months in both cases and controls. Norovirus Genotyping Tool and phylogenetic analysis of partial sequences of the 3′ end of the RNA-dependent RNA Polymerase (RdRp) and the capsid domain region were employed to assign genotypes of the norovirus strains. GII.4 was the most predominant capsid genotype detected at 39.5% followed by GII.6 at 14.9%. The GII.4 Hunter 2004 variant was the predominant strain detected. Six RdRP/capsid recombinants including GII.P7/GII.6, GII.P7/GII.14, GII.P7/GII.20, GII.P12/GII.13, GII.P17/GII.16, and GII.P21/GII.3 were also identified. This study of norovirus infection in young children in Cambodia suggests genetic diversity of norovirus as reported worldwide. PMID:28115947

  19. An efficient method of noroviruses recovery from oysters and clams

    NASA Astrophysics Data System (ADS)

    Zhou, Deqing; Ma, Liping; Zhao, Feng; Yao, Lin; Su, Laijin; Li, Xinguang

    2013-03-01

    Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis. Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish. The concentration and RNA extraction of NoVs are crucial steps of detecting NoVs in shellfish. This study aimed to select a simple, rapid and highly efficient recovery method of NoVs detection with real-time RT-PCR. Four methods of recovering GI.3 and GII.4 NoVs from spiked digestive tissues of oysters and clams, respectively, were compared, of them, the method involving proteinase K and PEG 8000 was found the most efficient. With this method, 9.3% and 13.1% of GI.3 and GII.4 NoVs were recovered from oysters and 9.6% and 12.3% of GI.3 and GII.4 NoVs were recovered from clams, respectively. This method was further used to detect NoVs in 84 oysters ( Crassostrea gigas) and 86 clams ( Ruditapes philippinarum) collected from 10 coastal cities in China from Jan. 2011 to Feb. 2012. The NoVs isolation rates were 10.47% of clams (9/86) and 7.14% of oysters (6/84). All the detected NoVs belonged to genotype GII. The NoVs recovery method selected is efficient for NoVs detection in oysters and clams.

  20. Molecular epidemiology of norovirus from patients with acute gastroenteritis in northwestern Spain.

    PubMed

    Manso, C F; Romalde, J L

    2015-01-01

    The high incidence of norovirus (NoV) infections seems to be related to the emergence of new variants that evolved by genetic drift of the capsid gene. In this work, that represents a first effort to describe the molecular epidemiology of NoV in the northwest of Spain, a total of eight different NoV genotypes (GII.1, GII.3, GII.4, GII.6, GII.7, GII.12, GII.13, GII.14) were detected. The major genotypes observed were GII.4 (45·42%) and GII.14 (34·9%), being detected in all age groups. In addition, and although most of GII.4 sequences belonged to 2006b (7·2%) and 2010 (50·35%) variants, the presence of new NoV variants was observed. Phylogenetic analysis revealed that a high number of GII.4 sequences (35·24%) could be assigned to the newly emerging Sydney 2012 variant, even during late 2010. The high prevalence of NoV GII.14 observed in this study may indicate the emergence of this genotype in Spain.

  1. Development of a Recombinase Polymerase Amplification Assay for Detection of Epidemic Human Noroviruses.

    PubMed

    Moore, Matthew D; Jaykus, Lee-Ann

    2017-01-09

    Human norovirus is a leading cause of viral gastroenteritis worldwide. Rapid detection could facilitate control, however widespread point-of-care testing is infrequently done due to the lack of robust and portable methods. Recombinase polymerase amplification (RPA) is a novel isothermal method which rapidly amplifies and detects nucleic acids using a simple device in near real-time. An RT-RPA assay targeting a recent epidemic human norovirus strain (GII.4 New Orleans) was developed and evaluated in this study. The assay successfully detected purified norovirus RNA from multiple patient outbreak isolates and had a limit of detection of 3.40 ± 0.20 log10 genomic copies (LGC), which is comparable to most other reported isothermal norovirus amplification methods. The assay also detected norovirus in directly boiled stool, and displayed better resistance to inhibitors than a commonly used RT-qPCR assay. The assay was specific, as it did not amplify genomes from 9 non-related enteric viruses and bacteria. The assay detected norovirus in some samples in as little as 6 min, and the entire detection process can be performed in less than 30 min. The reported RT-RPA method shows promise for sensitive point-of-care detection of epidemic human norovirus, and is the fastest human norovirus amplification method to date.

  2. Development of a Recombinase Polymerase Amplification Assay for Detection of Epidemic Human Noroviruses

    PubMed Central

    Moore, Matthew D.; Jaykus, Lee-Ann

    2017-01-01

    Human norovirus is a leading cause of viral gastroenteritis worldwide. Rapid detection could facilitate control, however widespread point-of-care testing is infrequently done due to the lack of robust and portable methods. Recombinase polymerase amplification (RPA) is a novel isothermal method which rapidly amplifies and detects nucleic acids using a simple device in near real-time. An RT-RPA assay targeting a recent epidemic human norovirus strain (GII.4 New Orleans) was developed and evaluated in this study. The assay successfully detected purified norovirus RNA from multiple patient outbreak isolates and had a limit of detection of 3.40 ± 0.20 log10 genomic copies (LGC), which is comparable to most other reported isothermal norovirus amplification methods. The assay also detected norovirus in directly boiled stool, and displayed better resistance to inhibitors than a commonly used RT-qPCR assay. The assay was specific, as it did not amplify genomes from 9 non-related enteric viruses and bacteria. The assay detected norovirus in some samples in as little as 6 min, and the entire detection process can be performed in less than 30 min. The reported RT-RPA method shows promise for sensitive point-of-care detection of epidemic human norovirus, and is the fastest human norovirus amplification method to date. PMID:28067278

  3. Characterization of norovirus infections in Seoul, Korea.

    PubMed

    Park, Sanghun; Jung, Jihun; Oh, Seah; Jung, Hyowon; Oh, Younghee; Cho, Seokju; Cho, Seogju; Cho, Sungja; Park, Hyongsug; Jo, Namsook; Bae, Kyungwon; Choi, Sungmin; Kim, Bogsoon; Kim, Junghun; Chae, Youngzoo; Jung, Haesook; Cheon, Doosung; Kim, Hyunsoo

    2012-10-01

    The present study has determined the detection rate of norovirus (NoV) with acute gastroenteritis (AGE) in hospitalized children and describes the molecular epidemiology of NoV circulating in Seoul, Korea. Six hundred and eighty-three (9.8%) of samples were positive for NoV. Of these, the NoV GII genogroup was the most commonly found, with a prevalence of 96.2% (683 of 710). Only 27 samples were positive for the NoV GI genogroup. Ten kinds of GI genotype (GI/1, GI/2, GI/3, GI/4, GI/5, GI/6, GI/7, GI/9, GI/12, and GI/13) and eight kinds of GII genotype (GII/2, GII/3, GII/4, GII/8, GII/14, GII/15, GII/16, and GII/17) were identified in children with AGE during the years 2008-2011.

  4. Human noroviruses recognize sialyl Lewis x neoglycoprotein.

    PubMed

    Rydell, Gustaf E; Nilsson, Jonas; Rodriguez-Diaz, Jesus; Ruvoën-Clouet, Nathalie; Svensson, Lennart; Le Pendu, Jacques; Larson, Göran

    2009-03-01

    The carbohydrate binding characteristics of a norovirus GII.3 (Chron1) and a GII.4 (Dijon) strain were investigated using virus-like particles (VLPs) and saliva samples from 81 individuals genotyped for FUT2 (secretor) and FUT3 (Lewis) and phenotyped for ABO and Lewis blood groups. The two VLPs showed a typical secretor-gene-dependent binding and bound significantly stronger to saliva from A, B, and AB than from O individuals (P < 0.0001 and P < 0.001) but did not bind to any samples from secretor-negative individuals. The GII.3 strain showed larger interindividual variation and bound stronger to saliva from B than from A(2) secretors (P < 0.01). When assaying for binding to neoglycoproteins, the GII.3 and GII.4 strains were compared with the Norwalk GI.1 prototype strain. Although all three strains bound to Lewis b (and H type 1 chain) glycoconjugates, only the two GII strains showed an additional binding to sialyl Lewis x. This novel binding was specific since the VLPs did not bind to structural analogs, e.g., Lewis x or sialyl Lewis a, but only to sialyl Lewis x, sialyl diLewis x and sialylated type 2 chain conjugates. In inhibition experiments, the sialyl Lewis x conjugate was the most potent inhibitor. The minimal requirement for this potential receptor structure is Neu5Ac alpha 3Gal beta 4(Fuc alpha 3)GlcNAc beta 3Gal beta- where Fuc is not absolutely necessary for binding. Our study shows that some human norovirus GII strains have at least two binding specificities: one secretor-gene-dependent related to alpha1,2-fucosylated carbohydrates and another related to alpha2,3-sialylated carbohydrates of the type 2 chain, e.g., sialyl Lewis x.

  5. Norovirus Infections

    MedlinePlus

    Noroviruses are a group of related viruses. Infection with these viruses causes an illness called gastroenteritis, an inflammation of the stomach and intestines. It can spread from person to person, or ...

  6. The transmissibility of noroviruses: Statistical modeling of outbreak events with known route of transmission in Japan

    PubMed Central

    Matsuyama, Ryota; Miura, Fuminari

    2017-01-01

    In Japan, the fraction of norovirus outbreaks attributable to human-to-human transmission has increased with time, and the timing of the increased fraction has coincided with the increase in the observed fraction of genogroup II genotype 4 (GII.4). The present study aimed to estimate the time-dependent changes in the transmissibility of noroviruses. The effective reproduction number (Ry), for year y, was estimated by analyzing the time series surveillance data for outbreak events from 2000 to 2016. Ry was estimated by using the fraction of outbreak events that were attributable to human-to-human transmission and by employing three different statistical models that are considered to mechanistically capture the possible data-generating process in different ways. The Ry estimates ranged from 0.14 to 4.15 in value, revealing an overall increasing trend (p<0.05 for all three models). The proportion of outbreaks caused by GII and GII.4 viruses among the total events also increased with time, and positive correlations were identified between transmissibility and these proportions. Parametric modeling of Ry indicated that the time-dependent patterns of Ry were better described by a step function plus linear trend rather than the step function alone that reflects the widespread use of reverse transcriptase PCR (RT-PCR) in and after 2007 for laboratory diagnosis. Accordingly, we conclude that norovirus transmissibility has increased over the past 16 years in Japan. The change is at least partially explained by the time-dependent domination of the contagious GII genogroup (e.g., GII.4), indicating that noroviruses better fitted to humans have selectively caused the human-to-human transmissions, thereby altering the epidemiology of this pathogen. PMID:28296972

  7. Assessment of Functional Norovirus Antibody Responses by Blocking Assay in Mice.

    PubMed

    Malm, Maria; Tamminen, Kirsi; Blazevic, Vesna

    2016-01-01

    Norovirus (NoV)-specific serum antibodies bind to NoV-derived virus-like particles (VLPs) and block the binding of VLPs to the host cell attachment factors/receptors, histo-blood group antigens (HBGAs). Blocking antibodies in human sera have been associated with a protection from NoV infection and disease. Studies of experimental NoV VLP-based vaccines measure blocking antibodies in animal sera instead of a traditional virus neutralization assay. This chapter describes the methodology for analyzing blocking antibodies from NoV GII.4 VLP-immunized mouse sera. Protocol for obtaining mouse NoV GII.4-specific immune sera is described, followed by the detailed protocol for blocking assay using synthetic HBGAs.

  8. Norovirus gastroenteritis.

    PubMed

    Goodgame, Richard

    2007-03-01

    Recent epidemiologic studies have shown that norovirus is one of the most frequent causes of acute nonbacterial gastroenteritis. Reverse-transcription polymerase chain reaction and nucleotide sequencing are the means by which the hundreds of norovirus strains have been identified, named, and classified into genogroups and genetic clusters. They are also the means by which a particular strain is traced from the source of an outbreak throughout its spread. These molecular techniques have been combined with classic epidemiology to investigate norovirus outbreaks in diverse settings, including hospitals, nursing homes, dining locations, schools, daycare centers, and vacation venues. Outbreaks are difficult to control because of the apparent ease of transmission through food, water, person-to-person contact, and environmental surfaces. Almost all patients with norovirus gastroenteritis recover completely, but hospital and nursing home outbreaks have been associated with morbidity and mortality. The diagnostic and management approach to an individual patient is to use clinical and epidemiologic findings to rule out "not norovirus." At the first sign that there is an outbreak, strict compliance with cleaning, disinfection, and work release guidelines is important to prevent further spread.

  9. High hydrostatic pressure inactivation of murine norovirus and human noroviruses on green onions and in salsa.

    PubMed

    Sido, Robert F; Huang, Runze; Liu, Chuhan; Chen, Haiqiang

    2017-02-02

    In this study, high hydrostatic pressure (HHP) was evaluated as an intervention for human noroviruses (HuNoVs) in green onions and salsa. To determine the effect of water during HHP treatment on virus inactivation, a HuNoV surrogate, murine norovirus 1 (MNV-1), was inoculated onto green onions and then HHP-treated at 350MPa with or without water at 4 or 20°C. The presence of water enhanced HHP inactivation of MNV-1 on green onions at 4°C but not at 20°C. To test the temperature effect on HHP inactivation of MNV-1, inoculated green onions were HHP-treated at 300MPa at 1, 4 and 10°C. As the temperature decreased, MNV-1 became more sensitive to HHP treatment. HHP inactivation curves of MNV-1 on green onions and salsa were obtained at 300 or 350MPa for 0.5-3min at 1°C. All three inactivation curves showed a linear relationship between log reduction of MNV-1 and time. D values of HHP inactivation of MNV-1 on green onions were 1.10 and 0.61min at 300 and 350MPa, respectively. The D value of HHP inactivation of MNV-1 in salsa at 300MPa was 0.63min. HHP inactivation of HuNoV GI.1 and GII.4 on green onions and salsa was also conducted. To achieve >3 log reduction of HuNoV GI.1, HHP treatments for 2min at 1°C should be conducted at 600MPa and 500MPa for green onions and salsa, respectively. To achieve >3 log reduction of HuNoV GII.4, HHP treatments for 2min at 1°C should be conducted at 500MPa and 300MPa for green onions and salsa, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Near Real-Time Surveillance of U.S. Norovirus Outbreaks by the Norovirus Sentinel Testing and Tracking Network - United States, August 2009-July 2015.

    PubMed

    Shah, Minesh P; Wikswo, Mary E; Barclay, Leslie; Kambhampati, Anita; Shioda, Kayoko; Parashar, Umesh D; Vinjé, Jan; Hall, Aron J

    2017-02-24

    Norovirus is the leading cause of endemic and epidemic acute gastroenteritis in the United States (1). New variant strains of norovirus GII.4 emerge every 2-4 years (2-4) and are often associated with increased disease and health care visits (5-7). Since 2009, CDC has obtained epidemiologic data on norovirus outbreaks from state health departments through the National Outbreak Reporting System (NORS) (8) and laboratory data through CaliciNet (9). NORS is a web-based platform for reporting waterborne, foodborne, and enteric disease outbreaks of all etiologies, including norovirus, to CDC. CaliciNet, a nationwide electronic surveillance system of local and state public health and regulatory agency laboratories, collects genetic sequences of norovirus strains associated with gastroenteritis outbreaks. Because these two independent reporting systems contain complementary data, integration of NORS and CaliciNet records could provide valuable public health information about norovirus outbreaks. However, reporting lags and inconsistent identification codes in NORS and CaliciNet records have been an obstacle to developing an integrated surveillance system.

  11. Norovirus: Food Handlers

    MedlinePlus

    ... Health, NEHA, Water Quality & Health Council, and American Chemistry Council Clean-up and Disinfection for Norovirus (“ ... Health, NEHA, Water Quality & Health Council, and American Chemistry Council Norovirus Illness: Key Facts [2 pages] Norovirus: ...

  12. Norovirus Illness: Key Facts

    MedlinePlus

    ... for days or weeks. • Norovirus can survive some disinfectants, making it hard to get rid of. Norovirus ... 5.25%] per gallon of water) or other disinfectant registered as effective against norovirus by the Environmental ...

  13. Binding to histo-blood group antigen-expressing bacteria protects human norovirus from acute heat stress

    PubMed Central

    Li, Dan; Breiman, Adrien; le Pendu, Jacques; Uyttendaele, Mieke

    2015-01-01

    This study aims to investigate if histo-blood group antigen (HBGA) expressing bacteria have any protective role on human norovirus (NoV) from acute heat stress. Eleven bacterial strains were included, belonging to Escherichia coli, Enterobacter cloacae, Enterobacter aerogenes, Clostridium difficile, Bifidobacterium adolescentis, and B. longum. HBGA expression of the bacteria as well as binding of human NoV virus-like particles (VLPs, GI.1, and GII.4 strains) to the bacteria were detected by flow cytometry. NoV VLPs pre-incubated with HBGA expressing or non-HBGA expressing bacteria were heated and detected by both direct ELISA and porcine gastric mucin-binding assay. The NoV-binding abilities of the bacteria correlated well with their HBGA expression profiles. Two HBGA expressing E. coli (LMG8223 and LFMFP861, both GI.1 and GII.4 binders) and one non-HBGA expressing E. coli (ATCC8739, neither GI.1 nor GII.4 binder) were selected for the heat treatment test with NoV VLPs. Compared with the same cell numbers of non-HBGA expressing E. coli, the presence of HBGA-expressing E. coli could always maintain higher antigen integrity, as well as mucin-binding ability of NoV VLPs of both GI.1 and GII.4 after heat-treatment at 90°C for 2 min. These results indicate that HBGA-expressing bacteria may protect NoVs during the food processing treatments, thereby facilitating their transmission. PMID:26191052

  14. Comparison of human saliva and synthetic histo-blood group antigens usage as ligands in norovirus-like particle binding and blocking assays.

    PubMed

    Uusi-Kerttula, Hanni; Tamminen, Kirsi; Malm, Maria; Vesikari, Timo; Blazevic, Vesna

    2014-06-01

    Blocking of norovirus-like particle binding to their cellular ligands, histo-blood group antigens with immune sera, is considered a surrogate norovirus neutralization assay. We compared human secretor positive saliva and synthetic biotinylated carbohydrates as a source of histo-blood group antigens in binding and blocking assays. Six norovirus capsid-derived virus-like particles belonging to genogroup I (GI-1-2001 and GI-3-2002) and genogroup II (GII-4-1999, GII-4-2010 New Orleans, GII-4-2012 Sydney and GII-12-1998) noroviruses were produced by a recombinant baculovirus expression system and binding profile to saliva type A, B and O and to synthetic antigens (A trimer, B trimer, H type 1, H type 3, Lewis(a) and Lewis(b)) was identified. Good correlation between virus-like particle binding to saliva type A and synthetic A trimer (r = 0.66, p < 0.05) and saliva type B and synthetic B trimer (r = 0.75, p < 0.05) was observed. Binding of each norovirus virus-like particle to the selected histo-blood group antigens was blocked by convalescent sera from NoV-infected subjects or type-specific mouse antisera. Our results support the use of either saliva or synthetic antigens in blocking assay to measure the ability of norovirus antisera to block virus-like particle binding to the carbohydrate ligands. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  15. Phylogenetic Analyses Suggest that Factors Other Than the Capsid Protein Play a Role in the Epidemic Potential of GII.2 Norovirus

    PubMed Central

    Tohma, Kentaro; Lepore, Cara J.; Ford-Siltz, Lauren A.

    2017-01-01

    ABSTRACT Norovirus is the leading cause of acute gastroenteritis worldwide. For over two decades, a single genotype (GII.4) has been responsible for most norovirus-associated cases. However, during the winter of 2014 to 2015, the GII.4 strains were displaced by a rarely detected genotype (GII.17) in several countries of the Asian continent. Moreover, during the winter of 2016 to 2017, the GII.2 strain reemerged as predominant in different countries worldwide. This reemerging GII.2 strain is a recombinant virus that presents a GII.P16 polymerase genotype. In this study, we investigated the evolutionary dynamics of GII.2 to determine the mechanism of this sudden emergence in the human population. The phylogenetic analyses indicated strong linear evolution of the VP1-encoding sequence, albeit with minor changes in the amino acid sequence over time. Without major genetic differences among the strains, a clustering based on the polymerase genotype was observed in the tree. This association did not affect the substitution rate of the VP1. Phylogenetic analyses of the polymerase region showed that reemerging GII.P16-GII.2 strains diverged into a new cluster, with a small number of amino acid substitutions detected on the surface of the associated polymerase. Thus, besides recombination or antigenic shift, point mutations in nonstructural proteins could also lead to novel properties with epidemic potential in different norovirus genotypes. IMPORTANCE Noroviruses are a major cause of gastroenteritis worldwide. Currently, there is no vaccine or specific antiviral available to treat norovirus disease. Multiple norovirus strains infect humans, but a single genotype (GII.4) has been regarded as the most important cause of viral gastroenteritis outbreaks worldwide. Its persistence and predominance have been explained by the continuous replacement of variants that present new antigenic properties on their capsid protein, thus evading the herd immunity acquired to the previous

  16. Phylogenetic Analyses Suggest that Factors Other Than the Capsid Protein Play a Role in the Epidemic Potential of GII.2 Norovirus.

    PubMed

    Tohma, Kentaro; Lepore, Cara J; Ford-Siltz, Lauren A; Parra, Gabriel I

    2017-01-01

    Norovirus is the leading cause of acute gastroenteritis worldwide. For over two decades, a single genotype (GII.4) has been responsible for most norovirus-associated cases. However, during the winter of 2014 to 2015, the GII.4 strains were displaced by a rarely detected genotype (GII.17) in several countries of the Asian continent. Moreover, during the winter of 2016 to 2017, the GII.2 strain reemerged as predominant in different countries worldwide. This reemerging GII.2 strain is a recombinant virus that presents a GII.P16 polymerase genotype. In this study, we investigated the evolutionary dynamics of GII.2 to determine the mechanism of this sudden emergence in the human population. The phylogenetic analyses indicated strong linear evolution of the VP1-encoding sequence, albeit with minor changes in the amino acid sequence over time. Without major genetic differences among the strains, a clustering based on the polymerase genotype was observed in the tree. This association did not affect the substitution rate of the VP1. Phylogenetic analyses of the polymerase region showed that reemerging GII.P16-GII.2 strains diverged into a new cluster, with a small number of amino acid substitutions detected on the surface of the associated polymerase. Thus, besides recombination or antigenic shift, point mutations in nonstructural proteins could also lead to novel properties with epidemic potential in different norovirus genotypes. IMPORTANCE Noroviruses are a major cause of gastroenteritis worldwide. Currently, there is no vaccine or specific antiviral available to treat norovirus disease. Multiple norovirus strains infect humans, but a single genotype (GII.4) has been regarded as the most important cause of viral gastroenteritis outbreaks worldwide. Its persistence and predominance have been explained by the continuous replacement of variants that present new antigenic properties on their capsid protein, thus evading the herd immunity acquired to the previous variants

  17. Nanobody Binding to a Conserved Epitope Promotes Norovirus Particle Disassembly

    PubMed Central

    Koromyslova, Anna D.

    2014-01-01

    specific for GII.10, whereas Nano-85 bound several different GII genotypes, including GII.4, GII.10, and GII.12. We showed that Nano-85 was able to detect norovirus virions in clinical stool specimens using a sandwich enzyme-linked immunosorbent assay. Importantly, we found that Nano-85 binding to intact particles caused the particles to disassemble. We believe that with further testing, Nano-85 not only will work as a diagnostic reagent in norovirus detection systems but also could function as a broadly reactive GII norovirus antiviral. PMID:25520510

  18. Norovirus and Sapovirus Epidemiology and Strain Characteristics among Navajo and Apache Infants.

    PubMed

    Grant, Lindsay R; O'Brien, Katherine L; Weatherholtz, Robert C; Reid, Raymond; Goklish, Novalene; Santosham, Mathuram; Parashar, Umesh; Vinjé, Jan

    2017-01-01

    Norovirus and sapovirus are important causes of acute gastroenteritis (AGE) among American Indian infants. We investigated the prevalence and molecular epidemiology of norovirus and sapovirus in American Indian infants who have historically experienced a high burden of AGE compared to other US populations. Stool samples were collected from 241 children with AGE (cases) and from 343 infants without AGE (controls) ≤9 months of age from 2002-2004. Cases experienced forceful vomiting and/or 3 or more watery or looser-than-normal stools in 24 hours. Stools were tested by real-time RT-PCR for norovirus GI, GII and GIV and sapovirus GI, GII, GIV and GV. Positive samples were genotyped after sequencing conventional RT-PCR products. Norovirus was identified in 76 (31.5%) of the cases and 70 (20.4%) of the controls (p<0.001). GII.3 and GII.4 Farmington Hills were the most frequently identified genotypes in 14.5% and 30.3% of cases and 17.1% and 27.1% of controls, respectively. Sapovirus GI and GII genotypes were identified in 8 (3.3%) of cases and 8 (2.3%) of controls and a single GIV virus was detected in a control. The same norovirus and sapovirus genotypes were circulating in the general U.S. population in the same time period. The high detection rate of norovirus in healthy controls suggests significant asymptomatic transmission in young infants in these communities.

  19. Molecular epidemiology of GI and GII noroviruses in sewage: 1-year surveillance in eastern China.

    PubMed

    Zhou, N; Lin, X; Wang, S; Tao, Z; Xiong, P; Wang, H; Liu, Y; Song, Y; Xu, A

    2016-10-01

    To determine the concentration and molecular epidemiology of GI and GII noroviruses in sewage in China. Twenty-three raw sewage samples were collected in the cities of Jinan and Linyi, eastern China in 2014. GI and GII noroviruses were positive in all samples after TaqMan-based quantitative PCR. The mean concentrations of GI and GII noroviruses were 4·52 × 10(4) and 7·88 × 10(4) genome copies per litre respectively. After reverse transcription-PCR, cloning and sequencing, 16 genotypes were identified. GI.6 (69·6%), GI.2 (65·2%), GII.13 (65·2%), GII.6 (60·9%) and GII.17 (60·9%) were the most common GI and GII genotypes. A recombination event was observed in two GI.6 sequences. GII.4 sequences belonged to Sydney 2012 and Den Haag 2006b variant. Interestingly, the novel GII.17 Kawasaki308 variant was detected. These results reveal that multiple norovirus genotypes cocirculated in the local population. The risk of acute gastroenteritis outbreak is high in the two cities due to the detection of GII.17 Kawasaki308 variant and the high concentration of norovirus in raw sewage. This study demonstrates sewage surveillance can be a useful approach to monitor norovirus circulating in the population. © 2016 The Society for Applied Microbiology.

  20. Human Norovirus and Its Surrogates Induce Plant Immune Response in Arabidopsis thaliana and Lactuca sativa.

    PubMed

    Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E

    2017-08-01

    Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.

  1. Norovirus and Sapovirus Epidemiology and Strain Characteristics among Navajo and Apache Infants

    PubMed Central

    O’Brien, Katherine L.; Weatherholtz, Robert C.; Reid, Raymond; Goklish, Novalene; Santosham, Mathuram; Parashar, Umesh; Vinjé, Jan

    2017-01-01

    Norovirus and sapovirus are important causes of acute gastroenteritis (AGE) among American Indian infants. We investigated the prevalence and molecular epidemiology of norovirus and sapovirus in American Indian infants who have historically experienced a high burden of AGE compared to other US populations. Stool samples were collected from 241 children with AGE (cases) and from 343 infants without AGE (controls) ≤9 months of age from 2002–2004. Cases experienced forceful vomiting and/or 3 or more watery or looser-than-normal stools in 24 hours. Stools were tested by real-time RT-PCR for norovirus GI, GII and GIV and sapovirus GI, GII, GIV and GV. Positive samples were genotyped after sequencing conventional RT-PCR products. Norovirus was identified in 76 (31.5%) of the cases and 70 (20.4%) of the controls (p<0.001). GII.3 and GII.4 Farmington Hills were the most frequently identified genotypes in 14.5% and 30.3% of cases and 17.1% and 27.1% of controls, respectively. Sapovirus GI and GII genotypes were identified in 8 (3.3%) of cases and 8 (2.3%) of controls and a single GIV virus was detected in a control. The same norovirus and sapovirus genotypes were circulating in the general U.S. population in the same time period. The high detection rate of norovirus in healthy controls suggests significant asymptomatic transmission in young infants in these communities. PMID:28046108

  2. Development of a Nanobody-Based Lateral Flow Immunoassay for Detection of Human Norovirus.

    PubMed

    Doerflinger, Sylvie Y; Tabatabai, Julia; Schnitzler, Paul; Farah, Carlo; Rameil, Steffen; Sander, Peter; Koromyslova, Anna; Hansman, Grant S

    2016-01-01

    Human noroviruses are the dominant cause of outbreaks of acute gastroenteritis. These viruses are usually detected by molecular methods, including reverse transcriptase PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Human noroviruses are genetically and antigenically diverse, with two main genogroups that are further subdivided into over 40 different genotypes. During the past decade, genogroup 2 genotype 4 (GII.4) has dominated in most countries, but recently, viruses belonging to GII.17 have increased in prevalence in a number of countries. A number of commercially available ELISAs and lateral flow immunoassays were found to have lower sensitivities to the GII.17 viruses, indicating that the antibodies used in these methods may not have a high level of cross-reactivity. In this study, we developed a rapid Nanobody-based lateral flow immunoassay (Nano-immunochromatography [Nano-IC]) for the detection of human norovirus in clinical specimens. The Nano-IC assay detected virions from two GII.4 norovirus clusters, which included the current dominant strain and a novel variant strain. The Nano-IC method had a sensitivity of 80% and specificity of 86% for outbreak specimens. Norovirus virus-like particles (VLPs) representing four genotypes (GII.4, GII.10, GII.12, and GII.17) could be detected by this method, demonstrating the potential in clinical screening. However, further modifications to the Nano-IC method are needed in order to improve this sensitivity, which may be achieved by the addition of other broadly reactive Nanobodies to the system. IMPORTANCE We previously identified a Nanobody (termed Nano-85) that bound to a highly conserved region on the norovirus capsid. In this study, the Nanobody was biotinylated and gold conjugated for a lateral flow immunoassay (termed Nano-IC). We showed that the Nano-IC assay was capable of detecting at least four antigenically distinct GII genotypes, including the newly emerging GII.17. In the clinical setting, the

  3. Development of a Nanobody-Based Lateral Flow Immunoassay for Detection of Human Norovirus

    PubMed Central

    Doerflinger, Sylvie Y.; Tabatabai, Julia; Schnitzler, Paul; Farah, Carlo; Rameil, Steffen; Sander, Peter; Koromyslova, Anna

    2016-01-01

    ABSTRACT Human noroviruses are the dominant cause of outbreaks of acute gastroenteritis. These viruses are usually detected by molecular methods, including reverse transcriptase PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Human noroviruses are genetically and antigenically diverse, with two main genogroups that are further subdivided into over 40 different genotypes. During the past decade, genogroup 2 genotype 4 (GII.4) has dominated in most countries, but recently, viruses belonging to GII.17 have increased in prevalence in a number of countries. A number of commercially available ELISAs and lateral flow immunoassays were found to have lower sensitivities to the GII.17 viruses, indicating that the antibodies used in these methods may not have a high level of cross-reactivity. In this study, we developed a rapid Nanobody-based lateral flow immunoassay (Nano-immunochromatography [Nano-IC]) for the detection of human norovirus in clinical specimens. The Nano-IC assay detected virions from two GII.4 norovirus clusters, which included the current dominant strain and a novel variant strain. The Nano-IC method had a sensitivity of 80% and specificity of 86% for outbreak specimens. Norovirus virus-like particles (VLPs) representing four genotypes (GII.4, GII.10, GII.12, and GII.17) could be detected by this method, demonstrating the potential in clinical screening. However, further modifications to the Nano-IC method are needed in order to improve this sensitivity, which may be achieved by the addition of other broadly reactive Nanobodies to the system. IMPORTANCE We previously identified a Nanobody (termed Nano-85) that bound to a highly conserved region on the norovirus capsid. In this study, the Nanobody was biotinylated and gold conjugated for a lateral flow immunoassay (termed Nano-IC). We showed that the Nano-IC assay was capable of detecting at least four antigenically distinct GII genotypes, including the newly emerging GII.17. In the clinical

  4. Clinical and epidemiological characteristics of norovirus gastroenteritis among hospitalized children in Lebanon.

    PubMed

    Melhem, Nada M; Zaraket, Hassan; Kreidieh, Khalil; Ali, Zeinab; Hammadi, Moza; Ghanem, Soha; Hajar, Farah; Haidar, Amjad; Inati, Adlette; Rajab, Mariam; Fakhouri, Hassan; Ghanem, Bassam; Baasiri, Ghassan; Dbaibo, Ghassan

    2016-12-28

    To assess the burden of norovirus (NoV) and to determine the diversity of circulating strains among hospitalized children in Lebanon. Stool samples were collected from children presenting with acute gastroenteritis to six major hospitals in Lebanon. A total of 739 eligible stool samples, testing negative for diarrhea caused by rotavirus as a possible viral pathogen, were collected between January 2011 and June 2013. A standardized questionnaire including demographic, epidemiological and clinical observations was used at the time of hospitalization of children presenting with diarrhea. Viral RNA was extracted from stool samples followed by reverse transcription polymerase chain reaction and nucleotide sequencing of a fragment of the viral protein 1 capsid gene. Multiple sequence alignments were carried out and phylogenetic trees were constructed using the MEGA 6 software. Overall, 11.2% of stool samples collected from children aged < 5 years tested positive for NoV genogroups I (GI) and II (GII). GII accounted for 10.6% of the gastroenteritis cases with only five samples being positive for GI (0.7%). The majority of hospitalized children showed symptoms of diarrhea, dehydration, vomiting and fever. Upon sequencing of positive samples and based on their clustering in the phylogenetic tree, 4/5 of GI gastroenteritis cases were designated GI.3 and one case as GI.4. GII.4 was predominantly detected in stool of our study participants (68%). We report a JB-15/KOR/2008 GII.4 Apeldoorn 2008-like variant strain circulating in 2011; this strain was replaced between 2012 and 2013 by a variant sharing homology with the Sydney/NSW0514/2012/AUS GII.4 Sydney 2012 and Sydney 2012/FRA GII.4 strains. We also report the co-circulation of non-GII.4 genotypes among hospitalized children. Our data show that NoV gastroenteritis can occur throughout the year with the highest number of cases detected during the hot months. The majority of NoV-associated viral gastroenteritis cases among our

  5. Clinical and epidemiological characteristics of norovirus gastroenteritis among hospitalized children in Lebanon

    PubMed Central

    Melhem, Nada M; Zaraket, Hassan; Kreidieh, Khalil; Ali, Zeinab; Hammadi, Moza; Ghanem, Soha; Hajar, Farah; Haidar, Amjad; Inati, Adlette; Rajab, Mariam; Fakhouri, Hassan; Ghanem, Bassam; Baasiri, Ghassan; Dbaibo, Ghassan

    2016-01-01

    AIM To assess the burden of norovirus (NoV) and to determine the diversity of circulating strains among hospitalized children in Lebanon. METHODS Stool samples were collected from children presenting with acute gastroenteritis to six major hospitals in Lebanon. A total of 739 eligible stool samples, testing negative for diarrhea caused by rotavirus as a possible viral pathogen, were collected between January 2011 and June 2013. A standardized questionnaire including demographic, epidemiological and clinical observations was used at the time of hospitalization of children presenting with diarrhea. Viral RNA was extracted from stool samples followed by reverse transcription polymerase chain reaction and nucleotide sequencing of a fragment of the viral protein 1 capsid gene. Multiple sequence alignments were carried out and phylogenetic trees were constructed using the MEGA 6 software. RESULTS Overall, 11.2% of stool samples collected from children aged < 5 years tested positive for NoV genogroups I (GI) and II (GII). GII accounted for 10.6% of the gastroenteritis cases with only five samples being positive for GI (0.7%). The majority of hospitalized children showed symptoms of diarrhea, dehydration, vomiting and fever. Upon sequencing of positive samples and based on their clustering in the phylogenetic tree, 4/5 of GI gastroenteritis cases were designated GI.3 and one case as GI.4. GII.4 was predominantly detected in stool of our study participants (68%). We report a JB-15/KOR/2008 GII.4 Apeldoorn 2008-like variant strain circulating in 2011; this strain was replaced between 2012 and 2013 by a variant sharing homology with the Sydney/NSW0514/2012/AUS GII.4 Sydney 2012 and Sydney 2012/FRA GII.4 strains. We also report the co-circulation of non-GII.4 genotypes among hospitalized children. Our data show that NoV gastroenteritis can occur throughout the year with the highest number of cases detected during the hot months. CONCLUSION The majority of NoV-associated viral

  6. Variable High-Pressure-Processing Sensitivities for Genogroup II Human Noroviruses

    PubMed Central

    Lou, Fangfei; DiCaprio, Erin; Li, Xinhui; Dai, Xianjun; Ma, Yuanmei; Hughes, John; Chen, Haiqiang; Kingsley, David H.

    2016-01-01

    ABSTRACT Human norovirus (HuNoV) is a leading cause of foodborne diseases worldwide. High-pressure processing (HPP) is one of the most promising nonthermal technologies for the decontamination of viral pathogens in foods. However, the survival of HuNoVs after HPP is poorly understood because these viruses cannot be propagated in vitro. In this study, we estimated the survival of different HuNoV strains within genogroup II (GII) after HPP treatment using viral receptor-binding ability as an indicator. Four HuNoV strains (one GII genotype 1 [GII.1] strain, two GII.4 strains, and one GII.6 strain) were treated at high pressures ranging from 200 to 600 MPa. After treatment, the intact viral particles were captured by porcine gastric mucin-conjugated magnetic beads (PGM-MBs) that contained histo-blood group antigens, the functional receptors for HuNoVs. The genomic RNA copies of the captured HuNoVs were quantified by real-time reverse transcriptase PCR (RT-PCR). Two GII.4 HuNoVs had similar sensitivities to HPP. The resistance of HuNoV strains against HPP ranked as follows: GII.1 > GII.6 > GII.4, with GII.4 being the most sensitive. Evaluation of temperature and matrix effects on HPP-mediated inactivation of HuNoV GII.4, GII.1, and GII.6 strains showed that HuNoV was more easily inactivated at lower temperatures and at a neutral pH. In addition, phosphate-buffered saline (PBS) and minimal essential medium (MEM) can provide protective effects against HuNoV inactivation compared to H2O. Collectively, this study demonstrated that (i) different HuNoV strains within GII exhibited different sensitivities to high pressure, and (ii) HPP is capable of inactivating HuNoV GII strains by optimizing pressure parameters. IMPORTANCE Human norovirus (HuNoV) is a leading cause of foodborne disease worldwide. Noroviruses are highly diverse, both antigenically and genetically. Genogroup II (GII) contains the majority of HuNoVs, with GII genotype 4 (GII.4) being the most prevalent

  7. Variable High-Pressure-Processing Sensitivities for Genogroup II Human Noroviruses.

    PubMed

    Lou, Fangfei; DiCaprio, Erin; Li, Xinhui; Dai, Xianjun; Ma, Yuanmei; Hughes, John; Chen, Haiqiang; Kingsley, David H; Li, Jianrong

    2016-10-01

    Human norovirus (HuNoV) is a leading cause of foodborne diseases worldwide. High-pressure processing (HPP) is one of the most promising nonthermal technologies for the decontamination of viral pathogens in foods. However, the survival of HuNoVs after HPP is poorly understood because these viruses cannot be propagated in vitro In this study, we estimated the survival of different HuNoV strains within genogroup II (GII) after HPP treatment using viral receptor-binding ability as an indicator. Four HuNoV strains (one GII genotype 1 [GII.1] strain, two GII.4 strains, and one GII.6 strain) were treated at high pressures ranging from 200 to 600 MPa. After treatment, the intact viral particles were captured by porcine gastric mucin-conjugated magnetic beads (PGM-MBs) that contained histo-blood group antigens, the functional receptors for HuNoVs. The genomic RNA copies of the captured HuNoVs were quantified by real-time reverse transcriptase PCR (RT-PCR). Two GII.4 HuNoVs had similar sensitivities to HPP. The resistance of HuNoV strains against HPP ranked as follows: GII.1 > GII.6 > GII.4, with GII.4 being the most sensitive. Evaluation of temperature and matrix effects on HPP-mediated inactivation of HuNoV GII.4, GII.1, and GII.6 strains showed that HuNoV was more easily inactivated at lower temperatures and at a neutral pH. In addition, phosphate-buffered saline (PBS) and minimal essential medium (MEM) can provide protective effects against HuNoV inactivation compared to H2O. Collectively, this study demonstrated that (i) different HuNoV strains within GII exhibited different sensitivities to high pressure, and (ii) HPP is capable of inactivating HuNoV GII strains by optimizing pressure parameters. Human norovirus (HuNoV) is a leading cause of foodborne disease worldwide. Noroviruses are highly diverse, both antigenically and genetically. Genogroup II (GII) contains the majority of HuNoVs, with GII genotype 4 (GII.4) being the most prevalent. Recently, GII.1 and GII.6

  8. A Multi-Site Study of Norovirus Molecular Epidemiology in Australia and New Zealand, 2013-2014

    PubMed Central

    Lim, Kun Lee; Hewitt, Joanne; Sitabkhan, Alefiya; Eden, John-Sebastian; Lun, Jennifer; Levy, Avram; Merif, Juan; Smith, David; Rawlinson, William D.; White, Peter A.

    2016-01-01

    Background Norovirus (NoV) is the major cause of acute gastroenteritis across all age groups. In particular, variants of genogroup II, genotype 4 (GII.4) have been associated with epidemics globally, occurring approximately every three years. The pandemic GII.4 variant, Sydney 2012, was first reported in early 2012 and soon became the predominant circulating NoV strain globally. Despite its broad impact, both clinically and economically, our understanding of the fundamental diversity and mechanisms by which new NoV strains emerge remains limited. In this study, we describe the molecular epidemiological trends of NoV-associated acute gastroenteritis in Australia and New Zealand between January 2013 and June 2014. Methodology Overall, 647 NoV-positive clinical faecal samples from 409 outbreaks and 238 unlinked cases of acute gastroenteritis were examined by RT-PCR and sequencing. Phylogenetic analysis was then performed to identify NoV capsid genotypes and to establish the temporal dominance of circulating pandemic GII.4 variants. Recombinant viruses were also identified based on analysis of the ORF1/2 overlapping region. Findings Peaks in NoV activity were observed, however the timing of these epidemics varied between different regions. Overall, GII.4 NoVs were the dominant cause of both outbreaks and cases of NoV-associated acute gastroenteritis (63.1%, n = 408/647), with Sydney 2012 being the most common GII.4 variant identified (98.8%, n = 403/408). Of the 409 reported NoV outbreaks, aged-care facilities were the most common setting in both Western Australia (87%, n = 20/23) and New Zealand (58.1%, n = 200/344) while most of the NoV outbreaks were reported from hospitals (38%, n = 16/42) in New South Wales, Australia. An analysis of a subset of non-GII.4 viruses from all locations (125/239) showed the majority (56.8%, n = 71/125) were inter-genotype recombinants. These recombinants were surprisingly diverse and could be classified into 18 distinct recombinant

  9. Biological and immunological characterization of norovirus major capsid proteins from three different genotypes.

    PubMed

    Huo, Yuqi; Wan, Xin; Ling, Tong; Shen, Shuo

    2016-01-01

    Noroviruses (NoVs) are the leading cause of non-bacterial acute gastroenteritis worldwide. Due to a lack of cell culture system and animal model, our understanding of NoVs has been lagging behind. In this study, NoV major capsid proteins (VP1) from three different genotypes (GI.2, GII.3 and GII.4) were expressed by using recombinant baculovirus expression system and which led to successful assembly of virus-like particles (VLPs). The receptor binding patterns of three kinds of VLPs were characterized by using synthetic and salivary HBGA-VLP binding assay. Cross-reactivity and cross-blocking activity of rabbit hyperimmune sera against these VLPs were determined by ELISA/Western blot analysis and saliva-VLP binding blockade assay, respectively. Expression of the major capsid proteins from three genotypes all led to smaller VLPs in dominance when sf9 cells were cultured in suspension, which was in consistence with our previous report. These smaller VLPs were used for in vitro synthetic and salivary HBGA-VLP binding and binding blockade assays. VLPs from GII.3 strain exhibited no binding to all synthetic HBGAs and saliva samples tested while VLPs from GI.2 and GII.4 strain showed similar binding pattern and bound to all salivary HBGAs tested. Rabbit anti-GII.3 VLPs hyperimmune serum didn't block the binding of GI.2 and GII.4 VLPs to salivary HBGAs while rabbit anti-GI.2 VLP hyperimmune serum blocked the binding of GII.4 VLPs to salivary HBGAs but not vice versa. Our results provide further evidence indirectly in support of presence of other factors involved in receptor binding other than HBGAs for NoVs, and demonstrate poor cross-blocking activities of antibodies against VLPs within or across genogroups. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Norovirus recombination.

    PubMed

    Bull, Rowena A; Tanaka, Mark M; White, Peter A

    2007-12-01

    RNA recombination is a significant driving force in viral evolution. Increased awareness of recombination within the genus Norovirus of the family Calicivirus has led to a rise in the identification of norovirus (NoV) recombinants and they are now reported at high frequency. Currently, there is no classification system for recombinant NoVs and a widely accepted recombinant genotyping system is still needed. Consequently, there is duplication in reporting of novel recombinants. This has led to difficulties in defining the number and types of recombinants in circulation. In this study, 120 NoV nucleotide sequences were compiled from the current GenBank database and published literature. NoV recombinants and their recombination breakpoints were identified using three methods: phylogenetic analysis, SimPlot analysis and the maximum chi2 method. A total of 20 NoV recombinant types were identified in circulation worldwide. The recombination point is the ORF1/2 overlap in all isolates except one, which demonstrated a double recombination event within the polymerase region.

  11. Genetic Diversity among Food-Borne and Waterborne Norovirus Strains Causing Outbreaks in Sweden▿

    PubMed Central

    Lysén, Maria; Thorhagen, Margareta; Brytting, Maria; Hjertqvist, Marika; Andersson, Yvonne; Hedlund, Kjell-Olof

    2009-01-01

    A total of 101 food-borne and waterborne outbreaks that were caused by norovirus and that resulted in more than 4,100 cases of illness were reported to the Swedish Institute for Infectious Disease Control from January 2002 to December 2006. Sequence and epidemiological data for isolates from 73 outbreaks were analyzed. In contrast to health care-related outbreaks, no clear seasonality could be observed. Sequence analysis showed a high degree of genetic variation among the noroviruses detected. Genogroup II (GII) viruses were detected in 70% of the outbreaks, and of those strains, strains of GII.4 were the most prevalent and were detected in 25% of all outbreaks. The GII.4 variants detected in global outbreaks in health care settings during 2002, 2004, and 2006 were also found in the food-borne outbreaks. GI strains totally dominated as the cause of water-related (drinking and recreational water) outbreaks and were found in 12 of 13 outbreaks. In 14 outbreaks, there were discrepancies among the polymerase and capsid genotype results. In four outbreaks, the polymerase of the recombinant GII.b virus occurred together with the GII.1 or GII.3 capsids, while the GII.7 polymerase occurred together with the GII.6 and GII.7 capsids. Mixed infections were observed in six outbreaks; four of these were due to contaminated water, and two were due to imported frozen berries. Contaminated food and water serve as important reservoirs for noroviruses. The high degree of genetic diversity found among norovirus strains causing food-borne and waterborne infections stresses the importance of the use of broad reaction detection methods when such outbreaks are investigated. PMID:19494060

  12. Norovirus contamination levels in ground water treatment systems used for food-catering facilities in South Korea.

    PubMed

    Lee, Bo-Ram; Lee, Sung-Geun; Park, Jong-Hyun; Kim, Kwang-Yup; Ryu, Sang-Ryeol; Rhee, Ok-Jae; Park, Jeong-Woong; Lee, Jeong-Su; Paik, Soon-Young

    2013-07-02

    This study aimed to inspect norovirus contamination of groundwater treatment systems used in food-catering facilities located in South Korea. A nationwide study was performed in 2010. Water samples were collected and, for the analysis of water quality, the temperature, pH, turbidity, and residual chlorine content were assessed. To detect norovirus genotypes GI and GII, RT-PCR and semi-nested PCR were performed with specific NV-GI and NV-GII primer sets, respectively. The PCR products amplified from the detected strains were then subjected to sequence analyses. Of 1,090 samples collected in 2010, seven (0.64%) were found to be norovirus-positive. Specifically, one norovirus strain was identified to have the GI-6 genotype, and six GII strains had the GII, GII-3, GII-4, and GII-17 genotypes. The very low detection rate of norovirus most likely reflects the preventative measures used. However, this virus can spread rapidly from person to person in crowded, enclosed places such as the schools investigated in this study. To promote better public health and sanitary conditions, it is necessary to periodically monitor noroviruses that frequently cause epidemic food poisoning in South Korea.

  13. Fluorinated TiO₂ as an ambient light-activated virucidal surface coating material for the control of human norovirus.

    PubMed

    Park, Geun Woo; Cho, Min; Cates, Ezra L; Lee, David; Oh, Byung-Taek; Vinjé, Jan; Kim, Jae-Hong

    2014-11-01

    We evaluated the virucidal efficacy of light-activated fluorinated TiO₂ surface coatings on human norovirus and several surrogates (bacteriophage MS2, feline calcivirus (FCV), and murine norovirus (MNV)). Inactivation of viruses on surfaces exposed to a common fluorescent lamp was monitored and the effects of UVA intensity, temperature, and fluoride content were assessed. Destruction of RNA and capsid oxidation were evaluated for human norovirus inocula on the F-TiO₂ surfaces, while contact with the F-TiO₂ surface and exposure to residual UVA radiation of 10 μW cm(-2) for 60 min resulted in infectivity reductions for the norovirus surrogates of 2-3 log₁₀. Infectivity reductions on pristine TiO₂ surfaces in identical conditions were over 2 orders of magnitude lower. Under realistic room lighting conditions, MS2 infectivity declined below the lower detection limit after 12h. Reductions in RNA were generally low, with the exception of GII.4, while capsid protein oxidation likely played a larger role in infectivity loss. Inactivation of norovirus surrogates occurred significantly faster on F-TiO₂ compared to pristine TiO₂ surfaces. The material demonstrated antiviral action against human norovirus surrogates and was shown to effectively inhibit MS2 when exposed to residual UVA present in fluorescent room lighting conditions in a laboratory setting.

  14. Type-specific and cross-reactive antibodies and T cell responses in norovirus VLP immunized mice are targeted both to conserved and variable domains of capsid VP1 protein.

    PubMed

    Malm, Maria; Tamminen, Kirsi; Vesikari, Timo; Blazevic, Vesna

    2016-10-01

    Norovirus (NoV)-specific antibodies, which block binding of the virus-like particles (VLPs) to the cell receptors are conformation dependent and directed towards the most exposed domain of the NoV capsid VP1 protein, the P2 domain. Limited data are available on the antibodies directed to other domains of the VP1, and even less on the NoV VP1-specific T cell epitopes. In here, BALB/c mice were immunized with six VLPs derived from NoV GII.4-1999, GII.4-2009 (New Orleans), GII.4-2012 (Sydney), GII.12, GI.1, and G1.3. Serum immunoglobulin G binding antibodies, histo-blood group antigen blocking antibodies and T cell responses using type-specific and heterologous NoV VLPs, P-dimers and 76 overlapping synthetic peptides, spanning the entire 539 amino acid sequence of GII.4 VP1, were determined. The results showed that at least half of the total antibody content is directed towards conserved S domain of the VP1. Only a small fraction (<1%) of the VP1 binding antibodies were blocking/neutralizing. With the use of matrix peptide pools and individual peptides, seven CD4(+) and CD8(+) T cell restricted epitopes were mapped, two located in S domain, four in P2 domain and one in P1 domain of NoV VP1. The epitopes were GII.4 strain-specific but also common GII.4 genotype-specific T cell epitopes were identified. More importantly, the results suggest a 9-amino acids long sequence ((318)PAPLGTPDF(326)) in P2 domain of VP1 as a universal NoV genogroup II-specific CD8(+) T cell epitope. Distribution of the T cell epitopes alongside the capsid VP1 indicates the need of the complete protein for high immunogenicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Norovirus Epidemiology in Africa: A Review.

    PubMed

    Mans, Janet; Armah, George E; Steele, A Duncan; Taylor, Maureen B

    2016-01-01

    Norovirus (NoV) is recognised as a leading cause of gastroenteritis worldwide across all age groups. The prevalence and diversity of NoVs in many African countries is still unknown, although early sero-prevalence studies indicated widespread early infection. Reports on NoVs in Africa vary widely in terms of study duration, population groups and size, inclusion of asymptomatic controls, as well as genotyping information. This review provides an estimate of NoV prevalence and distribution of genotypes of NoVs in Africa. Inclusion criteria for the review were study duration of at least 6 months, population size of >50 and diagnosis by RT-PCR. As regions used for genotyping varied, or genotyping was not always performed, this was not considered as an inclusion criteria. A literature search containing the terms norovirus+Africa yielded 74 publications. Of these 19 studies from 14 out of the 54 countries in Africa met the inclusion criteria. Data from studies not meeting the inclusion criteria, based on sample size or short duration, were included as discussion points. The majority of studies published focused on children, under five years of age, hospitalised with acute gastroenteritis. The mean overall prevalence was 13.5% (range 0.8-25.5%) in children with gastroenteritis and 9.7% (range 7-31%) in asymptomatic controls, where tested. NoV GII.4 was the predominant genotype identified in most of the studies that presented genotyping data. Other prevalent genotypes detected included GII.3 and GII.6. In conclusion, NoV is a common pathogen in children with diarrhoea in Africa, with considerable carriage in asymptomatic children. There is however, a paucity of data on NoV infection in adults.

  16. Norovirus Epidemiology in Africa: A Review

    PubMed Central

    Mans, Janet; Armah, George E.; Steele, A. Duncan; Taylor, Maureen B.

    2016-01-01

    Norovirus (NoV) is recognised as a leading cause of gastroenteritis worldwide across all age groups. The prevalence and diversity of NoVs in many African countries is still unknown, although early sero-prevalence studies indicated widespread early infection. Reports on NoVs in Africa vary widely in terms of study duration, population groups and size, inclusion of asymptomatic controls, as well as genotyping information. This review provides an estimate of NoV prevalence and distribution of genotypes of NoVs in Africa. Inclusion criteria for the review were study duration of at least 6 months, population size of >50 and diagnosis by RT-PCR. As regions used for genotyping varied, or genotyping was not always performed, this was not considered as an inclusion criteria. A literature search containing the terms norovirus+Africa yielded 74 publications. Of these 19 studies from 14 out of the 54 countries in Africa met the inclusion criteria. Data from studies not meeting the inclusion criteria, based on sample size or short duration, were included as discussion points. The majority of studies published focused on children, under five years of age, hospitalised with acute gastroenteritis. The mean overall prevalence was 13.5% (range 0.8–25.5%) in children with gastroenteritis and 9.7% (range 7–31%) in asymptomatic controls, where tested. NoV GII.4 was the predominant genotype identified in most of the studies that presented genotyping data. Other prevalent genotypes detected included GII.3 and GII.6. In conclusion, NoV is a common pathogen in children with diarrhoea in Africa, with considerable carriage in asymptomatic children. There is however, a paucity of data on NoV infection in adults. PMID:27116615

  17. Human norovirus culture in B cells

    PubMed Central

    Jones, Melissa K; Grau, Katrina R; Costantini, Veronica; Kolawole, Abimbola O; de Graaf, Miranda; Freiden, Pamela; Graves, Christina L; Koopmans, Marion; Wallet, Shannon M; Tibbetts, Scott A; Schultz-Cherry, Stacey; Wobus, Christiane E; Vinjé, Jan; Karst, Stephanie M

    2015-01-01

    Human noroviruses (HunoVs) are a leading cause of foodborne disease and severe childhood diarrhea, and they cause a majority of the gastroenteritis outbreaks worldwide. However, the development of effective and long-lasting HunoV vaccines and therapeutics has been greatly hindered by their uncultivability. We recently demonstrated that a HunoV replicates in human B cells, and that commensal bacteria serve as a cofactor for this infection. In this protocol, we provide detailed methods for culturing the GII.4-sydney HunoV strain directly in human B cells, and in a coculture system in which the virus must cross a confluent epithelial barrier to access underlying B cells. We also describe methods for bacterial stimulation of HunoV B cell infection and for measuring viral attachment to the surface of B cells. Finally, we highlight variables that contribute to the efficiency of viral replication in this system. Infection assays require 3 d and attachment assays require 3 h. analysis of infection or attachment samples, including rna extraction and rt-qpcr, requires ~6 h. PMID:26513671

  18. Evaluation of real-time RT-PCR assays for detection and quantification of norovirus genogroups I and II.

    PubMed

    Rupprom, Kitwadee; Chavalitshewinkoon-Petmitr, Porntip; Diraphat, Pornphan; Kittigul, Leera

    2017-02-20

    Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In this study, the performance of three TaqMan real-time RT-PCR assays was assessed, which were one commercially available real-time RT-PCR kit (assay A: Norovirus Real Time RT-PCR kit) and two in-house real-time RT-PCR assays (assay B: LightCycler RNA Master Hybprobe and assay C: RealTime ready RNA Virus Master). Assays A and B showed higher sensitivity than assay C for norovirus GI, while they all had the same sensitivity (10(3) DNA copies/mL) for GII DNA standard controls. Assay B had the highest efficiency for both genogroups. No cross-reactivity was observed among GI and GII noroviruses, rotavirus, hepatitis A virus, and poliovirus. The detection rates of these assays in GI and GII norovirus-positive fecal samples were not significantly different. However, the mean quantification cycle (Cq) value of assay B for GII was lower than assays A and C with statistical significance (P-value, 0.000). All three real-time RT-PCR assays could detect a variety of noroviruses including GI.2, GII.2, GII.3, GII.4, GII.6, GII.12, GII.17, and GII.21. This study suggests assay B as a suitable assay for the detection and quantification of noroviruses GI and GII due to good analytical sensitivity and higher performance to amplify norovirus on DNA standard controls and clinical samples.

  19. Comparative Evaluation of Norovirus Infection in Children with Acute Gastroenteritis by Rapid Immunochromatographic Test, RT-PCR and Real-time RT-PCR.

    PubMed

    Kumthip, Kattareeya; Khamrin, Pattara; Saikruang, Wilaiporn; Supadej, Kanittapon; Ushijima, Hiroshi; Maneekarn, Niwat

    2017-03-02

    Immunochromatographic (IC) test for norovirus detection is a rapid and simple detection method. This study evaluated the sensitivity and specificity of a recent version of R-Biopharm RIDA®QUICK Norovirus IC assay for norovirus detection in fecal specimens from children hospitalized with acute gastroenteritis. Fecal specimens were tested by IC kit in comparison with gold standard reverse transcription polymerase chain reaction (RT-PCR) and real-time RT-PCR. The IC kit showed high sensitivity and specificity comparable with PCR-based methods. None of false positive and false negative was found and the assay did not cross-react with other gastroenteritis viruses. The IC assay could detect genogroup I.5 (GI.5) and a wide range of genotypes in the GII noroviruses including GII.3, GII.4, GII.6, GII.7, GII.14, GII.15, GII.21, and also newly emerging GII.17 norovirus. In conclusion, this norovirus IC kit could be an alternative choice for rapid screening or a quick diagnostic tool for norovirus detection in fecal specimens of acute gastroenteritis patients.

  20. Human norovirus binding to select bacteria representative of the human gut microbiota

    PubMed Central

    Almand, Erin A.; Outlaw, Janie; Jaykus, Lee-Ann

    2017-01-01

    Recent reports describe the ability of select bacterial strains to bind human norovirus, although the specificity of such interactions is unknown. The purpose of this work was to determine if a select group of bacterial species representative of human gut microbiota bind to human norovirus, and if so, to characterize the intensity and location of that binding. The bacteria screened included naturally occurring strains isolated from human stool (Klebsiella spp., Citrobacter spp., Bacillus spp., Enterococcus faecium and Hafnia alvei) and select reference strains (Staphylococcus aureus and Enterobacter cloacae). Binding in PBS was evaluated to three human norovirus strains (GII.4 New Orleans 2009 and Sydney 2012, GI.6) and two surrogate viruses (Tulane virus and Turnip Crinkle Virus (TCV)) using a suspension assay format linked to RT-qPCR for quantification. The impact of different overnight culture media prior to washing on binding efficiency in PBS was also evaluated, and binding was visualized using transmission electron microscopy. All bacteria tested bound the representative human norovirus strains with high efficiency (<1 log10 of input virus remained unbound or <10% unbound and >90% binding efficiency) (p>0.05); there was selective binding for Tulane virus and no binding observed for TCV. Binding efficiency was highest when bacteria were cultured in minimal media (<1 log10 of input virus remained unbound, so >90% bound), but notably decreased when cultured in enriched media (1–3 log10 unbound or 0.01 –<90% bound)) (p<0.05). The norovirus-bacteria binding occurred around the outer cell surfaces and pili structures, without apparent localization. The findings reported here further elucidate and inform the dynamics between human noroviruses and enteric bacteria with implications for norovirus pathogenesis. PMID:28257478

  1. Human norovirus binding to select bacteria representative of the human gut microbiota.

    PubMed

    Almand, Erin A; Moore, Matthew D; Outlaw, Janie; Jaykus, Lee-Ann

    2017-01-01

    Recent reports describe the ability of select bacterial strains to bind human norovirus, although the specificity of such interactions is unknown. The purpose of this work was to determine if a select group of bacterial species representative of human gut microbiota bind to human norovirus, and if so, to characterize the intensity and location of that binding. The bacteria screened included naturally occurring strains isolated from human stool (Klebsiella spp., Citrobacter spp., Bacillus spp., Enterococcus faecium and Hafnia alvei) and select reference strains (Staphylococcus aureus and Enterobacter cloacae). Binding in PBS was evaluated to three human norovirus strains (GII.4 New Orleans 2009 and Sydney 2012, GI.6) and two surrogate viruses (Tulane virus and Turnip Crinkle Virus (TCV)) using a suspension assay format linked to RT-qPCR for quantification. The impact of different overnight culture media prior to washing on binding efficiency in PBS was also evaluated, and binding was visualized using transmission electron microscopy. All bacteria tested bound the representative human norovirus strains with high efficiency (<1 log10 of input virus remained unbound or <10% unbound and >90% binding efficiency) (p>0.05); there was selective binding for Tulane virus and no binding observed for TCV. Binding efficiency was highest when bacteria were cultured in minimal media (<1 log10 of input virus remained unbound, so >90% bound), but notably decreased when cultured in enriched media (1-3 log10 unbound or 0.01 -<90% bound)) (p<0.05). The norovirus-bacteria binding occurred around the outer cell surfaces and pili structures, without apparent localization. The findings reported here further elucidate and inform the dynamics between human noroviruses and enteric bacteria with implications for norovirus pathogenesis.

  2. Challenges of Culturing Human Norovirus in Three-Dimensional Organoid Intestinal Cell Culture Models

    PubMed Central

    Papafragkou, Efstathia; Hewitt, Joanne; Park, Geun Woo; Greening, Gail; Vinjé, Jan

    2013-01-01

    Human noroviruses are the most common cause of acute gastroenteritis worldwide. Recently, cell culture systems have been described using either human embryonic intestinal epithelial cells (Int-407) or human epithelial colorectal adenocarcinoma cells (Caco-2) growing on collagen-I porous micro carrier beads in a rotating bioreactor under conditions of physiological fluid shear. Here, we describe the efforts from two independent laboratories to implement this three dimensional (3D) cell culture system for the replication of norovirus. Int-407 and Caco-2 were grown in a rotating bioreactor for up to 28 days. Prior to infection, cells were screened for the presence of microvilli by electron microscopy and stained for junction proteins (zonula occludens-1, claudin-1, and β-catenin). Differentiated 3D cells were transferred to 24-well plates and infected with bacteria-free filtrates of various norovirus genotypes (GI.1, GI.3, GI.8, GII.2, GII.4, GII.7, and GII.8). At 12 h, 24 h, and 48 h post inoculation, viral RNA from both cells and supernatants were collected and analyzed for norovirus RNA by real-time reverse transcription PCR. Despite observations of high expression of junction proteins and microvilli development in stained thin sections, our data suggest no significant increase in viral titer based on norovirus RNA copy number during the first 48 h after inoculation for the different samples and virus culture conditions tested. Our combined efforts demonstrate that 3D cell culture models using Int-407 or Caco-2 cells do not support norovirus replication and highlight the complexity and difficulty of developing a reproducible in vitro cell culture system for human norovirus. PMID:23755105

  3. Challenges of culturing human norovirus in three-dimensional organoid intestinal cell culture models.

    PubMed

    Papafragkou, Efstathia; Hewitt, Joanne; Park, Geun Woo; Greening, Gail; Vinjé, Jan

    2014-01-01

    Human noroviruses are the most common cause of acute gastroenteritis worldwide. Recently, cell culture systems have been described using either human embryonic intestinal epithelial cells (Int-407) or human epithelial colorectal adenocarcinoma cells (Caco-2) growing on collagen-I porous micro carrier beads in a rotating bioreactor under conditions of physiological fluid shear. Here, we describe the efforts from two independent laboratories to implement this three dimensional (3D) cell culture system for the replication of norovirus. Int-407 and Caco-2 were grown in a rotating bioreactor for up to 28 days. Prior to infection, cells were screened for the presence of microvilli by electron microscopy and stained for junction proteins (zonula occludens-1, claudin-1, and β-catenin). Differentiated 3D cells were transferred to 24-well plates and infected with bacteria-free filtrates of various norovirus genotypes (GI.1, GI.3, GI.8, GII.2, GII.4, GII.7, and GII.8). At 12 h, 24 h, and 48 h post inoculation, viral RNA from both cells and supernatants were collected and analyzed for norovirus RNA by real-time reverse transcription PCR. Despite observations of high expression of junction proteins and microvilli development in stained thin sections, our data suggest no significant increase in viral titer based on norovirus RNA copy number during the first 48 h after inoculation for the different samples and virus culture conditions tested. Our combined efforts demonstrate that 3D cell culture models using Int-407 or Caco-2 cells do not support norovirus replication and highlight the complexity and difficulty of developing a reproducible in vitro cell culture system for human norovirus.

  4. Norovirus Polymerase Fidelity Contributes to Viral Transmission In Vivo.

    PubMed

    Arias, Armando; Thorne, Lucy; Ghurburrun, Elsa; Bailey, Dalan; Goodfellow, Ian

    2016-01-01

    Intrahost genetic diversity and replication error rates are intricately linked to RNA virus pathogenesis, with alterations in viral polymerase fidelity typically leading to attenuation during infections in vivo. We have previously shown that norovirus intrahost genetic diversity also influences viral pathogenesis using the murine norovirus model, as increasing viral mutation frequency using a mutagenic nucleoside resulted in clearance of a persistent infection in mice. Given the role of replication fidelity and genetic diversity in pathogenesis, we have now investigated whether polymerase fidelity can also impact virus transmission between susceptible hosts. We have identified a high-fidelity norovirus RNA-dependent RNA polymerase mutant (I391L) which displays delayed replication kinetics in vivo but not in cell culture. The I391L polymerase mutant also exhibited lower transmission rates between susceptible hosts than the wild-type virus and, most notably, another replication defective mutant that has wild-type levels of polymerase fidelity. These results provide the first experimental evidence that norovirus polymerase fidelity contributes to virus transmission between hosts and that maintaining diversity is important for the establishment of infection. This work supports the hypothesis that the reduced polymerase fidelity of the pandemic GII.4 human norovirus isolates may contribute to their global dominance. IMPORTANCE Virus replication fidelity and hence the intrahost genetic diversity of viral populations are known to be intricately linked to viral pathogenesis and tropism as well as to immune and antiviral escape during infection. In this study, we investigated whether changes in replication fidelity can impact the ability of a virus to transmit between susceptible hosts by the use of a mouse model for norovirus. We show that a variant encoding a high-fidelity polymerase is transmitted less efficiently between mice than the wild-type strain. This constitutes

  5. Norovirus Polymerase Fidelity Contributes to Viral Transmission In Vivo

    PubMed Central

    Thorne, Lucy; Ghurburrun, Elsa

    2016-01-01

    ABSTRACT Intrahost genetic diversity and replication error rates are intricately linked to RNA virus pathogenesis, with alterations in viral polymerase fidelity typically leading to attenuation during infections in vivo. We have previously shown that norovirus intrahost genetic diversity also influences viral pathogenesis using the murine norovirus model, as increasing viral mutation frequency using a mutagenic nucleoside resulted in clearance of a persistent infection in mice. Given the role of replication fidelity and genetic diversity in pathogenesis, we have now investigated whether polymerase fidelity can also impact virus transmission between susceptible hosts. We have identified a high-fidelity norovirus RNA-dependent RNA polymerase mutant (I391L) which displays delayed replication kinetics in vivo but not in cell culture. The I391L polymerase mutant also exhibited lower transmission rates between susceptible hosts than the wild-type virus and, most notably, another replication defective mutant that has wild-type levels of polymerase fidelity. These results provide the first experimental evidence that norovirus polymerase fidelity contributes to virus transmission between hosts and that maintaining diversity is important for the establishment of infection. This work supports the hypothesis that the reduced polymerase fidelity of the pandemic GII.4 human norovirus isolates may contribute to their global dominance. IMPORTANCE Virus replication fidelity and hence the intrahost genetic diversity of viral populations are known to be intricately linked to viral pathogenesis and tropism as well as to immune and antiviral escape during infection. In this study, we investigated whether changes in replication fidelity can impact the ability of a virus to transmit between susceptible hosts by the use of a mouse model for norovirus. We show that a variant encoding a high-fidelity polymerase is transmitted less efficiently between mice than the wild-type strain. This

  6. Molecular epidemiology of genogroup II norovirus infection among hospitalized children with acute gastroenteritis in Suzhou (Jiangsu, China) from 2010 to 2013.

    PubMed

    Fu, Jian-Guang; Ai, Jing; Zhang, Jun; Wu, Qing-Bin; Qi, Xian; Ji, Hong; Jin, Miao; Liu, Cheng; Wang, Shen-Jiao; Shan, Jun; Bao, Chang-Jun; Tang, Fen-Yang; Zhu, Ye-Fei

    2016-06-01

    Noroviruses (NoVs) are the most common cause of acute gastroenteritis in both sporadic and outbreak cases. Genotyping and recombination analyses were performed in order to help getting more knowledge of the distribution and genetic diversity of NoVs in Suzhou, located in Jiangsu province of China. All stool samples were collected from hospitalized children younger than 5 years old with acute gastroenteritis. For genotyping, the open reading frame (ORF) 1 and ORF2 were partially amplified and sequenced. 26.9% of stool samples were positive for genogroup II NoVs. The most common genotype was GII.4 and its variants included Den Haag-2006b, New Orleans-2009, and Sydney-2012. The Den Haag-2006b variants predominated during 2010-2012. In 2013, it was replaced by the Sydney-2012 variant. The second most common genotype was GII.12/GII.3. NoVs could be detected throughout the year, with GII.4 and GII.12/GII.3 coexisting during the cold months, and GII.4 was the main genotype during the warm months. The highest prevalence of NoV was detected in young children aged <24 months. Patients infected with GII.4 had a higher chance of getting moderate fever than other NoV-positive patients, while those infected with GII.12/GII.3 tended to have a mild degree of fever. NoV is an important pathogen responsible for viral gastroenteritis among children in Suzhou. Analyses of NoV circulating between 2010 and 2013 revealed a change of predominant variant of NoV GII.4 in each epidemic season and intergenotype recombinant strains represented an important part. © 2015 Wiley Periodicals, Inc.

  7. Occurrence of novel GII.17 and GII.21 norovirus variants in the coastal environment of South Korea in 2015

    PubMed Central

    Koo, Eung Seo; Kim, Man Su; Choi, Yong Seon; Park, Kwon-Sam; Jeong, Yong Seok

    2017-01-01

    Human norovirus (HNoV), a positive-sense RNA virus, is the main causative agent of acute viral gastroenteritis. Multiple pandemic variants of the genogroup II genotype 4 (GII.4) of NoV have attracted great attention from researchers worldwide. However, novel variants of GII.17 have been overtaking those pandemic variants in some areas of East Asia. To investigate the environmental occurrence of GII in South Korea, we collected water samples from coastal streams and a neighboring waste water treatment plant in North Jeolla province (in March, July, and December of 2015). Based on capsid gene region C analysis, four different genotypes (GII.4, GII.13, GII.17, and GII.21) were detected, with much higher prevalence of GII.17 than of GII.4. Additional sequence analyses of the ORF1-ORF2 junction and ORF2 from the water samples revealed that the GII.17 sequences in this study were closely related to the novel strains of GII.P17-GII.17, the main causative variants of the 2014–2015 HNoV outbreak in China and Japan. In addition, the GII.P21-GII.21 variants were identified in this study and they had new amino acid sequence variations in the blockade epitopes of the P2 domain. From these results, we present two important findings: 1) the novel GII.P17-GII.17 variants appeared to be predominant in the study area, and 2) new GII.21 variants have emerged in South Korea. PMID:28199388

  8. Occurrence of novel GII.17 and GII.21 norovirus variants in the coastal environment of South Korea in 2015.

    PubMed

    Koo, Eung Seo; Kim, Man Su; Choi, Yong Seon; Park, Kwon-Sam; Jeong, Yong Seok

    2017-01-01

    Human norovirus (HNoV), a positive-sense RNA virus, is the main causative agent of acute viral gastroenteritis. Multiple pandemic variants of the genogroup II genotype 4 (GII.4) of NoV have attracted great attention from researchers worldwide. However, novel variants of GII.17 have been overtaking those pandemic variants in some areas of East Asia. To investigate the environmental occurrence of GII in South Korea, we collected water samples from coastal streams and a neighboring waste water treatment plant in North Jeolla province (in March, July, and December of 2015). Based on capsid gene region C analysis, four different genotypes (GII.4, GII.13, GII.17, and GII.21) were detected, with much higher prevalence of GII.17 than of GII.4. Additional sequence analyses of the ORF1-ORF2 junction and ORF2 from the water samples revealed that the GII.17 sequences in this study were closely related to the novel strains of GII.P17-GII.17, the main causative variants of the 2014-2015 HNoV outbreak in China and Japan. In addition, the GII.P21-GII.21 variants were identified in this study and they had new amino acid sequence variations in the blockade epitopes of the P2 domain. From these results, we present two important findings: 1) the novel GII.P17-GII.17 variants appeared to be predominant in the study area, and 2) new GII.21 variants have emerged in South Korea.

  9. Semi-direct lysis of swabs and evaluation of their efficiencies to recover human noroviruses GI and GII from surfaces.

    PubMed

    De Keuckelaere, Ann; Stals, Ambroos; Uyttendaele, Mieke

    2014-06-01

    Enteric viruses such as noroviruses (NoVs) continue to be the cause of widespread viral outbreaks due to person-to-person transmission, contaminated food, and contaminated surfaces. In order to optimize swabbing methodology for the detection of viruses on (food) contact surfaces, three swab elution/extraction strategies were compared in part one of this study, out of which, one strategy was based on the recently launched ISO protocol (ISO/TS 15216-1) for the determination of hepatitis A virus and NoV in food using real-time RT-PCR (RT-qPCR). These three swab elution/extraction strategies were tested for the detection of GI.4 and GII.4 NoV on high-density polyethylene (HD-PE) surfaces with the use of cotton swabs. For detection of GI.4 and GII.4, the sample recovery efficiency (SRE) obtained with the direct lysis strategy (based on ISO/TS 15216-1) was significantly lower than the SRE obtained with both other strategies. The semi-direct lysis strategy was chosen to assess the SRE of two common swabs (cotton swab and polyester swab) versus the biowipe (Biomérieux, Lyon, France) on three surfaces (HD-PE, neoprene rubber (NR), and nitrile gloves (GL)). For both surfaces, HD-PE and GL, no significant differences in SREs of GI.4 and GII.4 NoVs were detected between the three different swabs. For the coarser NR, biowipes turned out to be the best option for detecting both GI.4 and GII.4 NoV.

  10. Molecular detection and characterization of noroviruses in river water in Thailand.

    PubMed

    Inoue, K; Motomura, K; Boonchan, M; Takeda, N; Ruchusatsawa, K; Guntapong, R; Tacharoenmuang, R; Sangkitporn, S; Chantaroj, S

    2016-03-01

    Norovirus (NoV) generally exists as a mixture of multiple genotype variants in nature. However, there has been no published report monitoring NoV in natural settings in Thailand. To obtain information on mixed presence of the NoV RNA genome, we conducted viral genome analysis of 15 water specimens collected from five sites in a river near Bangkok between August 2013 and August 2014. The number of viral RNA copies per specimen declined progressively from the most upstream to the most downstream site. Following direct nucleotide sequencing of the PCR products, we obtained three partial genome sequences of the NoV GI strain and 13 partial genome sequences of the NoV GII strains. Phylogenetic analysis indicated the presence of four GII.4 variant groups pro-circulated after the Den Haag_2006b, New Orleans_2009 and Sydney_2012 outbreaks. On the other hand, only GI.4 was observed from the specimens collected on April, 2014. These results indicated that multiple genogroups and genotypes of noroviruses are present and are circulating in the natural environment in Thailand as in other countries. Our study provides comprehensive information on the occurrence of new variants. Our study is the first paper that multiple genogroups and genotypes of norovirus exist, and are circulating in the river water near Bangkok, Thailand. Phylogenetic analysis indicated the presence of four GII.4 variant groups pro-circulated after the Den Haag_2006b, New Orleans_2009 and Sydney_2012 that caused outbreaks in the world. Continued research will be essential for understanding the natural history of NoV and the control of future outbreaks. © 2015 The Society for Applied Microbiology.

  11. Detection of norovirus genotype I.3b and II.4 in bioaccumulated blue mussels using different virus recovery methods.

    PubMed

    Comelli, Heidi Lange; Rimstad, Espen; Larsen, Stig; Myrmel, Mette

    2008-09-30

    Noroviruses (NoVs) are the most common non bacterial human pathogens associated with shellfish borne gastroenteritis. Norovirus detection is based on molecular procedures such as reverse transcriptase (RT)-PCR. A variety of methods have been developed to extract viral RNA from complex shellfish matrixes and to reduce the level of RT-PCR inhibitors. The present study had three objectives: 1) Determine the most appropriate sample treatment protocol for detection of NoVs in mussels, 2) Examine whether there is a variation of the binding affinity between a NoV GI and a GII strain to mussel digestive tissue and how this influences the detection sensitivity, 3) Establish an internal control for sample processing and virus detection. Three RNA extraction methods were evaluated on extracts from blue mussels (Mytilus edulis) spiked with NoV GII.4. The most efficient RNA extraction method was subsequently used for evaluation of three virus recovery methods of blue mussels bio accumulated with NoV GI.3b and GII.4. Mengovirus was evaluated as an internal process control and TaqMan RT-PCRs were used for virus detection. Elution of the two viruses from shellfish tissue differed, indicating a difference in binding affinities. Only a method based upon Proteinase K digestion followed by NucliSenseasyMAG was able to detect both NoV GI.3b and GII.4 (3.0% and 3.5% recovery respectively). The results show that the processing method influences the possibility to detect different variants of NoV.

  12. Characterisation of a household norovirus outbreak occurred in Valencia (Spain).

    PubMed

    Carmona-Vicente, Noelia; Fernández-Jiménez, Manuel; Vila-Vicent, Susana; Rodríguez-Díaz, Jesús; Buesa, Javier

    2016-03-12

    Human noroviruses (NoVs) are the main cause of non-bacterial gastroenteritis worldwide. Several studies have linked human susceptibility to NoVs with the expression of histo-blood group antigens (HBGAs). In January 2012, a NoV gastroenteritis outbreak affected a household in Valencia, Spain, and the personal susceptibility to NoV was investigated. To reach this aim 8 members of the affected household were recruited for this study and their secretor status, ABO and Lewis antigens were determined. NoV-specific saliva IgA and serum IgG antibody titers were analyzed. Their capacity to block viral binding to saliva receptors was analyzed, using virus-like particles (VLPs) of the NoV GII.4 genotype, 2006b variant, and saliva from a secretor O blood type donor. The most relevant finding was that an asymptomatic non-secretor individual shed NoVs in his stools. Interestingly, anti-NoV IgA antibody titers in saliva from secretor and non-secretor individuals showed no differences. On the contrary, high titers of NoV-specific IgG antibody were found in both convalescent sera and in sera collected 1 year post-infection, but only from secretor individuals. NoV GII.4-2006b VLP binding to receptors present in the saliva was efficiently blocked only by sera from secretor positive individuals. Despite the small number of individuals involved in this outbreak, this study reinforces the idea that susceptibility to human NoV is both dependent on the HBGA profile of the individuals as well as on the viral genotype and variant. We also show that the immunity to NoV lasts for at least 1 year after infection, demonstrating that symptomatic infections strongly stimulate immune responses.

  13. Occurrence of norovirus infection in an asymptomatic population in Indonesia.

    PubMed

    Utsumi, Takako; Lusida, Maria Inge; Dinana, Zayyin; Wahyuni, Rury Mega; Yamani, Laura Navika; Juniastuti; Soetjipto; Matsui, Chieko; Deng, Lin; Abe, Takayuki; Doan, Yen Hai; Fujii, Yoshiki; Kimura, Hirokazu; Katayama, Kazuhiko; Shoji, Ikuo

    2017-08-24

    Norovirus (NoV) is a major cause of nonbacterial acute gastroenteritis worldwide in all age groups, and asymptomatic individuals may contribute to NoV transmission as a reservoir. Nonetheless, little information is available regarding asymptomatic NoV infection in Indonesia. We performed an epidemiological analysis of NoV infection among asymptomatic healthy volunteers in the city of Surabaya, Indonesia (population ~2.75 million). A total of 512 stool samples from 18 individuals (age range 20-42years) collected from July 2015 to June 2016 were examined. The detection of NoV and the genotype classification were carried out by a reverse transcription-polymerase chain reaction (RT-PCR) direct sequencing method. NoV was detected in 14 of the 512 stool samples (2.7%), with 7 individuals (38.9%) having at least 1 positive stool sample. All 14 of the NoV strains detected belonged to genogroup GII. The phylogenetic analysis indicated that 10 strains (71.4%) were grouped with GII.2, 2 (14.3%) were GII.17, 1 was GII.4 Sydney 2012, and 1 was GII.1. The circulation of GII.Pg/GII.1 and GII.Pe/GII.4 Sydney 2012 recombinant variants was detected among an asymptomatic population in Surabaya, Indonesia. Of the 7 positive individuals, 2 were repeatedly infected with the same strain and heterogenous strains. Taken together, our results suggest that the excretion of NoV from healthy individuals is one of the sources of NoV outbreak. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Norovirus Infection in Harbor Porpoises

    PubMed Central

    Bodewes, Rogier; van Elk, Cornelis E.; van de Bildt, Marco; Getu, Sarah; Aron, Georgina I.; Verjans, Georges M.G.M.; Osterhaus, Albert D.M.E.; van den Brand, Judith M.A.; Kuiken, Thijs; Koopmans, Marion P.G.

    2017-01-01

    A norovirus was detected in harbor porpoises, a previously unknown host for norovirus. This norovirus had low similarity to any known norovirus. Viral RNA was detected primarily in intestinal tissue, and specific serum antibodies were detected in 8 (24%) of 34 harbor porpoises from the North Sea. PMID:27983498

  15. Genotype considerations for virus-like particle-based bivalent norovirus vaccine composition.

    PubMed

    Malm, Maria; Tamminen, Kirsi; Lappalainen, Suvi; Uusi-Kerttula, Hanni; Vesikari, Timo; Blazevic, Vesna

    2015-06-01

    Norovirus (NoV) genogroup I (GI) and GII are responsible for most human infections with NoV. Because of the high genetic variability of NoV, natural infection does not induce sufficient protective immunity to different genotypes or to variants of the same genotype and there is little or no cross-protection against different genogroups. NoV-derived virus-like particles (VLPs) are promising vaccine candidates that induce high levels of NoV-specific humoral and cellular immune responses. It is believed that a bivalent NoV vaccine consisting of a representative VLP from GI and GII is a minimum requirement for an effective vaccine. Here, we compared the abilities of monovalent immunizations with NoV GI.1-2001, GI.3-2002, GII.4-1999, and GII.4-2010 New Orleans VLPs to induce NoV type-specific and cross-reactive immune responses and protective blocking antibody responses in BALB/c mice. All of the VLPs induced comparable levels of type-specific serum IgG antibodies, as well as blocking antibodies to the VLPs used for immunization. However, the abilities of different VLP genotypes to induce cross-reactive IgG and cross-blocking antibodies varied remarkably. Our results confirm previous findings of a lack of cross-protective immune responses between GI and GII NoVs. These data support the rationale for including NoV GI.3 and GII.4-1999 VLPs in the bivalent vaccine formulation, which could be sufficient to induce protective immune responses across NoV genotypes in the two common genogroups in humans. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. Detection and Genetic Analysis of Noroviruses and Sapoviruses in Sea Snail.

    PubMed

    Ozawa, Hiroki; Kumazaki, Makoto; Ueki, Satoshi; Morita, Masahiro; Usuku, Shuzo

    2015-12-01

    An outbreak of acute gastroenteritis occurred at a restaurant in Yokohama in December 2011. Because many of the customers had consumed raw sea snail, sea snail was suspected to be the source of this outbreak. To determine whether sea snail contains Norovirus (NoV) or Sapovirus (SaV), we analyzed 27 sea snail samples collected over 5 months (May, June, August, October, and December 2012) and 59.3% were positive for NoV and/or SaV. The levels of NoV ranged from 1.5 × 10(3) to 1.5 × 10(5) copies/g tissue, and those of SaV from 1.5 × 10(2) to 1.3 × 10(3) copies/g tissue. The highest levels were observed in sea snails collected in December. A phylogenetic analysis of the NoVs showed that the viral strains were NoV genotypes GI.4, GI.6, GII.4, GII.12, GII.13, and GII.14, and the SaV strains were genotypes GI.2 and GI.3. The NoV GII.4 Sydney 2012 variants were only detected in December. This variant was a major source of gastroenteritis in Japan in the winter of 2012/2013. In contrast, the NoV GII.4 strains detected in May and June 2012 were not the Sydney 2012 variant. This study demonstrates that sea snail contains multiple genogroups and genotypes of NoV and SaV strains. We conclude that the sea snail presents a risk of gastroenteritis when consumed raw.

  17. Predominance of Norovirus and Sapovirus in Nicaragua after Implementation of Universal Rotavirus Vaccination

    PubMed Central

    Bucardo, Filemón; Reyes, Yaoska; Svensson, Lennart; Nordgren, Johan

    2014-01-01

    Background Despite significant reduction of rotavirus (RV) infections following implementation of RotaTeq vaccination in Nicaragua, a large burden of patients with diarrhea persists. Methods We conducted a community- and hospital-based study of the burden of RV, norovirus (NV) and sapovirus (SV) infections as cause of sporadic acute gastroenteritis (GE) among 330 children ≤ 5 years of age between September 2009 and October 2010 in two major cities of Nicaragua with a RotaTeq coverage rate of 95%. Results We found that NV, SV and RV infections altogether accounted for 45% of cases of GE. Notably, NV was found in 24% (79/330) of the children, followed by SV (17%, 57/330) and RV (8%, 25/330). The detection rate in the hospital setting was 27%, 15% and 14% for NV, SV and RV respectively, whereas in the community setting the detection rate of RV was < 1%. Among each of the investigated viruses one particular genogroup or genotype was dominant; GII.4 (82%) for NV, GI (46%) for SV and G1P[8] (64%) in RV. These variants were also found in higher proportions in the hospital setting compared to the community setting. The GII.4.2006 Minerva strain circulating globally since 2006 was the most common among genotyped NV in this study, with the GII.4-2010 New Orleans emerging in 2010. Conclusions This study shows that NV has become the leading viral cause of gastroenteritis at hospital and community settings in Nicaragua after implementation of RV vaccination. PMID:24849288

  18. Increase of GII.2 norovirus infections during the 2009-2010 season in Osaka City, Japan.

    PubMed

    Iritani, Nobuhiro; Kaida, Atsushi; Abe, Niichiro; Sekiguchi, Jun-Ichiro; Kubo, Hideyuki; Takakura, Koh-Ichi; Goto, Kaoru; Ogura, Hisashi; Seto, Yoshiyuki

    2012-03-01

    During the 2009-2010 season, a significant numerical increase of genotype GII.2 norovirus (NoV)-associated outbreaks was observed in Osaka City, Japan. The most common genotype in that season was GII.2 (44.6%), followed by GII.4 (39.2%). Mostly, GII.2 strains were associated with outbreaks in children and with person-to-person contact. The National Infectious Disease Surveillance Center reported that GII.2 NoV infections were widespread in Japan in that season. Comparative phylogenetic analysis of RNA-dependent RNA polymerase (RdRp) and capsid sequences revealed that this GII.2 epidemic resulted from two genetic strains. The first, GII.2p2 strains, had an identical genotype in the RdRp and capsid genes. GII.2p2 strains in the 2009-2010 season were a different genetic cluster from the strains of spring 2004, the previous epidemic of GII.2 NoV, but showed no unique amino acid change. The second, GII.2 chimera virus (GII.2p16), had GII.16 RdRp and GII.2 capsid genotypes, suggesting prior recombination at the junction of ORF1 and ORF2. GII.2p16 strains had four significant amino acid changes in the P2 subdomain, suggesting antigenic changes. Before the 2009-2010 season, GII.2 chimera viruses had been observed only sporadically. This spreading of GII.2p16 strains in the 2009-2010 season might be the first epidemic of GII.2 chimera virus. This study revealed that the NoV epidemic in the 2009-2010 season differed considerably from the prior season, when GII.4 was predominant. Furthermore, GII.2 strains persisted in human populations by drastic recombination and gradual accumulation of mutations, indicating a prevalent pattern of non-GII.4 genotypes with genetic evolution.

  19. Norovirus-Specific Memory T Cell Responses in Adult Human Donors

    PubMed Central

    Malm, Maria; Tamminen, Kirsi; Vesikari, Timo; Blazevic, Vesna

    2016-01-01

    Norovirus (NoV) is a leading cause of acute gastroenteritis in people of all ages worldwide. NoV-specific serum antibodies which block the binding of NoV virus-like particles (VLPs) to the cell receptors have been thoroughly investigated. In contrast, only a few publications are available on the NoV capsid VP1 protein-specific T cell responses in humans naturally infected with the virus. Freshly isolated peripheral blood mononuclear cells of eight healthy adult human donors previously exposed to NoV were stimulated with purified VLPs derived from NoV GII.4-1999, GII.4-2012 (Sydney), and GI.3, and IFN-γ production was measured by an ELISPOT assay. In addition, 76 overlapping synthetic peptides spanning the entire 539-amino acid sequence of GII.4 VP1 were pooled into two-dimensional matrices and used to identify putative T cell epitopes. Seven of the eight subjects produced IFN-γ in response to the peptides and five subjects produced IFN-γ in response to the VLPs of the same origin. In general, stronger T cell responses were induced with the peptides in each donor compared to the VLPs. A CD8+ T cell epitope in the shell domain of the VP1 (134SPSQVTMFPHIIVDVRQL151) was identified in two subjects, both having human leukocyte antigen (HLA)-A∗02:01 allele. To our knowledge, this is the first report using synthetic peptides to study NoV-specific T cell responses in human subjects and identify T cell epitopes. PMID:27752254

  20. Seroepidemiology of Norovirus-Associated Travelers’ Diarrhea

    PubMed Central

    Ajami, Nadim J.; Kavanagh, Owen V.; Ramani, Sasirekha; Crawford, Sue E.; Atmar, Robert L.; Jiang, Zhi-Dong; Okhuysen, Pablo C.; Estes, Mary K.; DuPont, Herbert L.

    2014-01-01

    Background Noroviruses (NoVs) are the most common cause of epidemic gastroenteritis, responsible for at least 50% of all gastroenteritis outbreaks worldwide and were recently identified as a leading cause of travelers’ diarrhea (TD) in U.S. and European travelers to Mexico, Guatemala and India. Methods Serum and diarrheic stool samples were collected from 75 US student travelers to Cuernavaca, Mexico, who developed TD. NoV RNA was detected in acute diarrheic stool samples using RT-PCR. Serology assays were performed using GI.1 Norwalk virus (NV) and GII.4 Houston virus (HOV) virus-like particles (VLP) to measure serum levels of IgA and IgG by Dissociation-Enhanced Lanthanide Fluorescent Immunoassay (DELFIA); serum IgM was measured by capture ELISA, and the 50% antibody blocking titer (BT50) was determined by a carbohydrate-blocking assay. Results NoV infection was identified in 12 (16%; 9 GI-NoV and 3 GII-NoV) of 75 travelers by either RT-PCR or ≥4-fold rise in antibody titer. Significantly more individuals had detectable pre-existing IgA antibodies against HOV (62/75, 83%) than against NV (49/75, 65%) (p=0.025) VLPs. A significant difference was observed between NV- and HOV-specific preexisting IgA antibody levels (p=0.0037), IgG (p=0.003) and BT50 (p=<0.0001). None of the NoV-infected TD travelers had BT50 >200, a level that has been described previously as a possible correlate of protection. Conclusions We found that GI-NoVs are commonly associated with TD cases identified in U.S. adults traveling to Mexico, and seroprevalence rates and geometric mean antibody levels to a GI-NoV were lower than to a GII-NoV strain. PMID:24383649

  1. Report of Recombinant Norovirus GII.g/GII.12 in Beijing, China

    PubMed Central

    Sang, Shaowei; Zhao, Zhongtang; Suo, Jijiang; Xing, Yubin; Jia, Ning; Gao, Yan; Xie, Lijun; Du, Mingmei; Liu, Bowei; Ren, Shiwang; Liu, Yunxi

    2014-01-01

    Background Norovirus (NoV) has been recognized as the most important cause of nonbacterial acute gastroenteritis affecting all age group people in the world. Genetic recombination is a common occurance in RNA viruses and many recombinant NoV strains have been described since it was first reported in 1997. However, the knowledge of recombinant NoV in China is extremely limited. Methods A total of 685 stool specimens were tested for NoV infection from the acute gastroenteritis patients who visited one general hospital in Beijing from April 2009 to November 2011. The virus recombination was identified by constructing phylogenetic trees of two genes, further SimPlot and the maximum chi-square analysis. Results The overall positive rate was 9.6% (66/685). GII.4 New Orleans 2009 and GII.4 2006b variants were the dominant genotype. Four GII.g/GII.12 and one GII.12/GII.3 recombinant strains were confirmed, and all derived from adult outpatients. The predictive recombination point occurred at the open reading frame (ORF)1/ORF2 overlap. Conclusions The GII.g ORF1/GII.12ORF2 recombinant has been reported in several countries and it was the first report of this recombinant in China. PMID:24505432

  2. Development of a Practical Method to Detect Noroviruses Contamination in Composite Meals.

    PubMed

    Saito, Hiroyuki; Toho, Miho; Tanaka, Tomoyuki; Noda, Mamoru

    2015-09-01

    Various methods to detect foodborne viruses including norovirus (NoV) in contaminated food have been developed. However, a practical method suitable for routine examination that can be applied for the detection of NoVs in oily, fatty, or emulsive food has not been established. In this study, we developed a new extraction and concentration method for detecting NoVs in contaminated composite meals. We spiked NoV-GI.4 or -GII.4 stool suspension into potato salad and stir-fried noodles. The food samples were suspended in homogenizing buffer and centrifuged to obtain a food emulsion. Then, anti-NoV-GI.4 or anti-NoV-GII.4 rabbit serum raised against recombinant virus-like particles or commercially available human gamma globulin and Staphylococcus aureus fixed with formalin as a source of protein A were added to the food emulsion. NoV-IgG-protein A-containing bacterial complexes were collected by centrifugation, and viral RNA was extracted. The detection limits of NoV RNA were 10-35 copies/g food for spiked NoVs in potato salad and stir-fried noodles. Human gamma globulin could also concentrate other NoV genotypes as well as other foodborne viruses, including sapovirus, hepatitis A virus, and adenovirus. This newly developed method can be used as to identify NoV contamination in composite foods and is also possibly applicable to other foodborne viruses.

  3. Investigation and control of a Norovirus outbreak of probable waterborne transmission through a municipal groundwater system.

    PubMed

    Giammanco, Giovanni M; Di Bartolo, Ilaria; Purpari, Giuseppa; Costantino, Claudio; Rotolo, Valentina; Spoto, Vittorio; Geraci, Gaetano; Bosco, Girolama; Petralia, Agata; Guercio, Annalisa; Macaluso, Giusi; Calamusa, Giuseppe; De Grazia, Simona; Ruggeri, Franco M; Vitale, Francesco; Maida, Carmelo M; Mammina, Caterina

    2014-09-01

    During March 2011 an outbreak of gastroenteritis occurred in Santo Stefano di Quisquina, Agrigento, Sicily, Italy. Within two weeks 156 cases were identified among the 4,965 people living in the municipality. An epidemiological investigation was conducted to characterize the outbreak and target the control measures. A case was defined as a person developing diarrhea or vomiting during February 27-March 13, 2011. Stool specimens were collected from 12 cases. Norovirus (NoV) genotype GII.4 variant New Orleans 2009 was identified in stool samples from 11 of 12 cases tested (91.7%). Epidemiological investigations suggested a possible association with municipal drinking water consumption. Water samples from the public water system were tested for NoV and a variety of genotypes were detected during the first 3 months of surveillance, including GII.4 strains belonging to different variants from that involved in the gastroenteritis outbreak. Contamination of the well and springs supplying the public water network was eventually thought to be the source of the NoV contamination.

  4. Human norovirus occurrence and diversity in the Llobregat river catchment, Spain.

    PubMed

    Pérez-Sautu, Unai; Sano, Daisuke; Guix, Susana; Kasimir, Georg; Pintó, Rosa M; Bosch, Albert

    2012-02-01

    Human noroviruses (NoV) were quantified and characterized in an 18 month survey conducted along the Llobregat river catchment in Spain. Sample types included freshwater, untreated and treated wastewater and drinking water. High NoV genome copy numbers were reported, reaching up to 10(6)  l(-1) and 10(9)  l(-1) in freshwater and raw sewage respectively. In both types of samples, GII NoV genome copies outnumbered those of GI, although without significance. All samples of semi-treated and treated drinking water were negative for NoV. A clear seasonality of NoV occurrence was observed both in river water and sewage samples, with significantly higher genome copy numbers in the cold than in the warm months period. Mean NoV log reduction rates after biological treatment of sewage were 2.2 and 3.1 for GI and GII respectively. A total of 77 NoV strains isolated in the Llobregat river catchment could be phylogenetically characterized, 44 belonging to GI and 33 to GII. The most prevalent genotype was GI.4, followed by GII.4 and GII.21. Several variants of the pandemic GII.4 strain were detected in the environment, corroborating their circulation among the population. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  5. Efficacy of Neutral Electrolyzed Water for Inactivation of Human Norovirus.

    PubMed

    Moorman, Eric; Montazeri, Naim; Jaykus, Lee-Ann

    2017-08-15

    Human norovirus (NoV) is the leading cause of acute gastroenteritis worldwide. Persistence on surfaces and resistance to many conventional disinfectants contribute to widespread transmission of norovirus. We examined the efficacy of neutral electrolyzed water (NEW; pH 7) for inactivation of human NoV GII.4 Sydney in suspension (ASTM method 1052-11) and on stainless steel surfaces (ASTM method 1053-11) with and without an additional soil load. The impact of the disinfectant on viral capsid was assessed using reverse transcriptase quantitative PCR (RT-qPCR; with an RNase pretreatment), SDS-PAGE, transmission electron microscopy, and a histo-blood group antigen (HBGA) receptor-binding assay. These studies were done in parallel with those using Tulane virus (TuV), a cultivable human NoV surrogate. Neutral electrolyzed water at 250 ppm free available chlorine produced a 4.8- and 0.4-log10 reduction in NoV genome copy number after 1 min in suspension and on stainless steel, respectively. Increasing the contact time on surfaces to 5, 10, 15, and 30 min reduced human NoV genomic copies by 0.5, 1.6, 2.4, and 5.0 log10 and TuV infectious titers by 2.4, 3.0, 3.8, and 4.1 log10 PFU, respectively. Increased soil load effectively eliminated antiviral efficacy regardless of testing method and virus. Exposure to NEW induced a near complete loss of receptor binding (5 ppm, 30 s), degradation of VP1 major capsid protein (250 ppm, 5 min), and increased virus particle aggregation (150 ppm, 30 min). Neutral electrolyzed water at 250 ppm shows promise as an antinoroviral disinfectant when used on precleaned stainless steel surfaces.IMPORTANCE Norovirus is the leading cause of acute viral gastroenteritis worldwide. Transmission occurs by fecal-oral or vomitus-oral routes. The persistence of norovirus on contaminated environmental surfaces exacerbates its spread, as does its resistance to many conventional disinfectants. The purpose of this research was to evaluate the antinoroviral

  6. Detection and molecular characterization of norovirus from oysters implicated in outbreaks in the US.

    PubMed

    Woods, Jacquelina W; Calci, Kevin R; Marchant-Tambone, Joey G; Burkhardt, William

    2016-10-01

    Human noroviruses are the leading cause of non-bacterial shellfish associated gastroenteritis. Here we report on the detection and characterization of norovirus (NoV) in shellfish associated outbreaks. Requests were received from state and federal officials for technical assistance in the analysis of shellfish for NoV and male specific coliphage (MSC; an enteric virus surrogate) during the years 2009 thru 2014. In outbreaks where NoV was detected, genogroup II (GII) levels ranged from 2.4 to 82.0 RT-qPCR U/g of digestive diverticula (DD) while NoV genogroup I (GI) levels ranged from 1.5 to 29.8 RT-qPCR U/g of DD. Murine norovirus extraction efficiencies ranged between 50 and 85%. MSC levels ranged from <6 to 80 PFU/100 g. Phylogenetic analysis of the outbreak sequences revealed strains clustering with GI.8, GI.4, GII.3, GII.4, GII.7, and GII.21. There was 100% homology between the shellfish and clinical strains occurring in 2 of 8 outbreaks. Known shellfish consumption data demonstrated probable infectious particles ingested as low as 12. These investigations demonstrate effective detection, quantification, and characterization of NoV in shellfish associated with illness. Published by Elsevier Ltd.

  7. Human norovirus infection of caco-2 cells grown as a three-dimensional tissue structure.

    PubMed

    Straub, Timothy M; Bartholomew, Rachel A; Valdez, Catherine O; Valentine, Nancy B; Dohnalkova, Alice; Ozanich, Richard M; Bruckner-Lea, Cynthia J; Call, Douglas R

    2011-06-01

    Human norovirus (hNoV) infectivity was studied using a three-dimensional model of large intestinal epithelium. Large intestine Caco-2 cells were grown in rotating wall vessel bioreactors for 18-21 days at 37 degrees C and then transferred to 24-well tissue culture plates where they were infected with GI.1 and GII.4 human noroviruses collected from human challenge trials and various outbreak settings, respectively. Compared with uninfected cells, transmission micrographs of norovirus-infected cells displayed evidence of shortening or total loss of apical microvilli, and vacuolization. Quantitative reverse transcription real-time PCR (qRT-PCR) indicated an approximate 2-3 log10 increase in viral RNA copies for the infected cells. A passage experiment examined both the ability for continued viral RNA and viral antigen detection. In the passaged samples 1.01x10(6) copies ml(-1) were detected by qRT-PCR. Immune electron microscopy using primary antibody to hNoV GI.1 capsids in conjunction with 6 nm gold-labelled secondary antibodies was performed on crude cellular lysates. Localization of antibody was observed in infected but not for uninfected cells. Our present findings, coupled with earlier work with the three-dimensional small intestinal INT407 model, demonstrate the utility of 3-D cell culture methods to develop infectivity assays for enteric viruses that do not readily infect mammalian cell cultures.

  8. Broad Blockade Antibody Responses in Human Volunteers after Immunization with a Multivalent Norovirus VLP Candidate Vaccine: Immunological Analyses from a Phase I Clinical Trial

    PubMed Central

    Lindesmith, Lisa C.; Ferris, Martin T.; Mullan, Clancy W.; Ferreira, Jennifer; Debbink, Kari; Swanstrom, Jesica; Richardson, Charles; Goodwin, Robert R.; Baehner, Frank; Mendelman, Paul M.; Bargatze, Robert F.; Baric, Ralph S.

    2015-01-01

    Background Human noroviruses (NoVs) are the primary cause of acute gastroenteritis and are characterized by antigenic variation between genogroups and genotypes and antigenic drift of strains within the predominant GII.4 genotype. In the context of this diversity, an effective NoV vaccine must elicit broadly protective immunity. We used an antibody (Ab) binding blockade assay to measure the potential cross-strain protection provided by a multivalent NoV virus-like particle (VLP) candidate vaccine in human volunteers. Methods and Findings Sera from ten human volunteers immunized with a multivalent NoV VLP vaccine (genotypes GI.1/GII.4) were analyzed for IgG and Ab blockade of VLP interaction with carbohydrate ligand, a potential correlate of protective immunity to NoV infection and illness. Immunization resulted in rapid rises in IgG and blockade Ab titers against both vaccine components and additional VLPs representing diverse strains and genotypes not represented in the vaccine. Importantly, vaccination induced blockade Ab to two novel GII.4 strains not in circulation at the time of vaccination or sample collection. GII.4 cross-reactive blockade Ab titers were more potent than responses against non-GII.4 VLPs, suggesting that previous exposure history to this dominant circulating genotype may impact the vaccine Ab response. Further, antigenic cartography indicated that vaccination preferentially activated preexisting Ab responses to epitopes associated with GII.4.1997. Study interpretations may be limited by the relevance of the surrogate neutralization assay and the number of immunized participants evaluated. Conclusions Vaccination with a multivalent NoV VLP vaccine induces a broadly blocking Ab response to multiple epitopes within vaccine and non-vaccine NoV strains and to novel antigenic variants not yet circulating at the time of vaccination. These data reveal new information about complex NoV immune responses to both natural exposure and to vaccination, and

  9. Application of Long-Range and Binding Reverse Transcription-Quantitative PCR To Indicate the Viral Integrities of Noroviruses

    PubMed Central

    De Keuckelaere, Ann; Uyttendaele, Mieke

    2014-01-01

    This study intends to establish and apply methods evaluating both viral capsid and genome integrities of human noroviruses (NoVs), which thus far remain nonculturable. Murine norovirus 1 (MNV-1) and human NoV GII.4 in phosphate-buffered saline suspensions were treated with heat, UV light, or ethanol and detected by reverse transcription-quantitative PCR (RT-qPCR), long-range RT-qPCR, binding RT-qPCR, and binding long-range RT-qPCR. For MNV-1 heated at 60°C for 2 and 30 min, limited reductions of genomic copies (<0.3-log) were obtained by RT-qPCR and long-range RT-qPCR, while the cell-binding pretreatments obtained higher reductions (>1.89-log reduction after 60°C for 30 min by binding long-range RT-qPCR). The human NoV GII.4 was found to be more heat resistant than MNV-1. For both MNV-1 and human NoV GII.4 after UV treatments of 20 and 200 mJ/cm2, no significant difference (P > 0.05) was observed between the dose-dependent reductions obtained by the four detection methodologies. Treatment of 70% ethanol for 1 min was shown to be more effective for inactivation of both MNV-1 and human NoV GII.4 than the heat and UV treatments used in this study. Subsequently, eight raspberry and four shellfish samples previously shown to be naturally contaminated with human NoVs by RT-qPCR (GI and GII; thus, 24 RT-qPCR signals) were subjected to comparison by this method. RT-qPCR, long-range RT-qPCR, binding RT-qPCR, and binding long-range RT-qPCR detected 20/24, 14/24, 24/24, and 23/24 positive signals, respectively, indicating the abundant presence of intact NoV particles. PMID:25107982

  10. Application of long-range and binding reverse transcription-quantitative PCR to indicate the viral integrities of noroviruses.

    PubMed

    Li, Dan; De Keuckelaere, Ann; Uyttendaele, Mieke

    2014-10-01

    This study intends to establish and apply methods evaluating both viral capsid and genome integrities of human noroviruses (NoVs), which thus far remain nonculturable. Murine norovirus 1 (MNV-1) and human NoV GII.4 in phosphate-buffered saline suspensions were treated with heat, UV light, or ethanol and detected by reverse transcription-quantitative PCR (RT-qPCR), long-range RT-qPCR, binding RT-qPCR, and binding long-range RT-qPCR. For MNV-1 heated at 60°C for 2 and 30 min, limited reductions of genomic copies (<0.3-log) were obtained by RT-qPCR and long-range RT-qPCR, while the cell-binding pretreatments obtained higher reductions (>1.89-log reduction after 60°C for 30 min by binding long-range RT-qPCR). The human NoV GII.4 was found to be more heat resistant than MNV-1. For both MNV-1 and human NoV GII.4 after UV treatments of 20 and 200 mJ/cm(2), no significant difference (P > 0.05) was observed between the dose-dependent reductions obtained by the four detection methodologies. Treatment of 70% ethanol for 1 min was shown to be more effective for inactivation of both MNV-1 and human NoV GII.4 than the heat and UV treatments used in this study. Subsequently, eight raspberry and four shellfish samples previously shown to be naturally contaminated with human NoVs by RT-qPCR (GI and GII; thus, 24 RT-qPCR signals) were subjected to comparison by this method. RT-qPCR, long-range RT-qPCR, binding RT-qPCR, and binding long-range RT-qPCR detected 20/24, 14/24, 24/24, and 23/24 positive signals, respectively, indicating the abundant presence of intact NoV particles. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  11. Crystal Structures of GII.10 and GII.12 Norovirus Protruding Domains in Complex with Histo-Blood Group Antigens Reveal Details for a Potential Site of Vulnerability

    SciTech Connect

    Hansman, Grant S.; Biertümpfel, Christian; Georgiev, Ivelin; McLellan, Jason S.; Chen, Lei; Zhou, Tongqing; Katayama, Kazuhiko; Kwong, Peter D.

    2011-10-10

    Noroviruses are the dominant cause of outbreaks of gastroenteritis worldwide, and interactions with human histo-blood group antigens (HBGAs) are thought to play a critical role in their entry mechanism. Structures of noroviruses from genogroups GI and GII in complex with HBGAs, however, reveal different modes of interaction. To gain insight into norovirus recognition of HBGAs, we determined crystal structures of norovirus protruding domains from two rarely detected GII genotypes, GII.10 and GII.12, alone and in complex with a panel of HBGAs, and analyzed structure-function implications related to conservation of the HBGA binding pocket. The GII.10- and GII.12-apo structures as well as the previously solved GII.4-apo structure resembled each other more closely than the GI.1-derived structure, and all three GII structures showed similar modes of HBGA recognition. The primary GII norovirus-HBGA interaction involved six hydrogen bonds between a terminal {alpha}fucose1-2 of the HBGAs and a dimeric capsid interface, which was composed of elements from two protruding subdomains. Norovirus interactions with other saccharide units of the HBGAs were variable and involved fewer hydrogen bonds. Sequence analysis revealed a site of GII norovirus sequence conservation to reside under the critical {alpha}fucose1-2 and to be one of the few patches of conserved residues on the outer virion-capsid surface. The site was smaller than that involved in full HBGA recognition, a consequence of variable recognition of peripheral saccharides. Despite this evasion tactic, the HBGA site of viral vulnerability may provide a viable target for small molecule- and antibody-mediated neutralization of GII norovirus.

  12. Detection and molecular characterization of human noroviruses in Korean groundwater between 2008 and 2010.

    PubMed

    Lee, Gyu-Cheol; Jheong, Weon-Hwa; Jung, Gyoo Seung; Oh, Sung-Ae; Kim, Min-jeong; Rhee, Ok-Jae; Park, Sujeong; Lee, Chan Hee

    2012-09-01

    RT-PCR, nucleotide sequencing, and phylogenetic analysis were performed for genotyping and molecular characterization of noroviruses isolated from Korean groundwater. Among 160 samples collected from 80 sites between 2008 and 2010, 14 samples (8.7 %) from 12 sites were positive for noroviruses (NoVs). The percentages of NoV-positive samples in 2008, 2009, and 2010 were 22.2, 3.2, and 0 %, respectively, representing a yearly decrease. GII-positive samples (n = 9, 5.6 %) outnumbered GI-positive samples (n = 5, 3.1 %). The genotypes of the GI NoVs were GI.2, GI.5, and GI.6, and the genotypes of the GII NoVs were all GII.4. One sample, HM623465, was very similar to CUK-3 and CBNU2 and two GII.4 sequences isolated from the stool of Korean gastroenteritis patients. A BLASTN search revealed several nucleotide sequences highly similar to those of NoVs isolated in this study. The original isolation sources for these similar NoVs were mostly stool (n = 731, 80.0 %) and groundwater (n = 135, 14.8 %), and all the countries from which they were isolated were almost in Asia (96.0 %); specifically, China (n = 192, 21.0 %), Japan (n = 383, 41.9 %), Korea (n = 296, 32.4 %), and other Asian countries (n = 6, 0.7 %). These results suggest that Korean groundwater might be contaminated with NoVs from the stool of infected patients and that these NoVs in turn cause new cases of gastroenteritis through a typical fecal-oral route with region-specific circulation. Therefore, it is important to properly treat sewage, which may include waterborne viruses and manage point sources in groundwater for national health and sanitation. In addition, continuous molecular surveillance remains important for understanding circulating NoVs.

  13. Persistence of human norovirus in reconstituted pesticides--pesticide application as a possible source of viruses in fresh produce chains.

    PubMed

    Verhaelen, Katharina; Bouwknegt, Martijn; Rutjes, Saskia A; de Roda Husman, Ana Maria

    2013-01-01

    The consumption of fresh produce is frequently associated with outbreaks of human norovirus (hNoV) disease. To prevent the contamination of fresh produce with hNoV, knowledge of the possible introduction sources of the viruses, such as water, is needed to be able to implement appropriate and efficient preventive measures. Contaminated water used to reconstitute pesticides could be a relevant source of infectious hNoV, determined by the initial level of virus contamination and the persistence of these viruses in reconstituted pesticides. We studied the persistence of hNoV GI.4, hNoV GII.4 and murine norovirus (MNV-1), the only culturable norovirus, in eight different pesticides after 0 and 2h. Virus concentrations were determined by reverse transcriptase PCR, and infectivity of MNV-1 was determined by endpoint dilutions followed by maximum likelihood estimations. MNV-1 was found to remain infectious in seven of the eight tested pesticides at the highest concentration applied in practice. In the presence of the insecticide Vertimec, MNV-1 infectivity decreased rapidly with a 1.9 log(10)-unit reduction at timepoint T(0). Also, the concentration of NoV GI.4 RNA decreased considerably with a 1.7 log(10)-unit reduction; whereas the detected PCR fragment of hNoV GII.4 remained stable. Assuming a similar persistence of infectious MNV-1 and hNoV we can conclude that water containing hNoV used to dilute pesticides may be an important source of infectious hNoV in fresh produce chains. The application of pesticides may therefore not only be a chemical hazard, but also a microbiological hazard for public health. The inclusion of antiviral substances in reconstituted pesticides may be appropriate to reduce the virological health risk posed by the application of pesticides.

  14. Molecular epidemiology of noroviruses associated with sporadic gastroenteritis in children in Novosibirsk, Russia, 2003-2012.

    PubMed

    Zhirakovskaia, Elena V; Tikunov, Artem Yu; Bodnev, Sergey A; Klemesheva, Vera V; Netesov, Sergey V; Tikunova, Nina V

    2015-05-01

    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. © 2015 Wiley Periodicals, Inc.

  15. Advances in Norovirus Biology

    PubMed Central

    Karst, Stephanie M.; Wobus, Christiane E.; Goodfellow, Ian G.; Green, Kim Y.

    2014-01-01

    Human noroviruses are a major cause of epidemic and sporadic gastroenteritis worldwide, and can chronically infect immunocompromised patients. Efforts to develop effective vaccines and antivirals have been hindered by the uncultivable nature and extreme genetic diversity of human noroviruses. Although they remain a particularly challenging pathogen to study, recent advances in norovirus animal models and in vitro cultivation systems have led to an increased understanding of norovirus molecular biology and replication, pathogenesis, cell tropism, and innate and adaptive immunity. Furthermore, clinical trials of vaccines consisting of nonreplicating virus-like particles have shown promise. In this review, we summarize these recent advances and discuss controversies in the field, which is rapidly progressing towards generation of antiviral agents and increasingly effective vaccines. PMID:24922570

  16. Advances in norovirus biology.

    PubMed

    Karst, Stephanie M; Wobus, Christiane E; Goodfellow, Ian G; Green, Kim Y; Virgin, Herbert W

    2014-06-11

    Human noroviruses are a major cause of epidemic and sporadic gastroenteritis worldwide and can chronically infect immunocompromised patients. Efforts to develop effective vaccines and antivirals have been hindered by the uncultivable nature and extreme genetic diversity of human noroviruses. Although they remain a particularly challenging pathogen to study, recent advances in norovirus animal models and in vitro cultivation systems have led to an increased understanding of norovirus molecular biology and replication, pathogenesis, cell tropism, and innate and adaptive immunity. Furthermore, clinical trials of vaccines consisting of nonreplicating virus-like particles have shown promise. In this review, we summarize these recent advances and discuss controversies in the field, which is rapidly progressing toward generation of antiviral agents and increasingly effective vaccines. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Environmental Surveillance for Noroviruses in Selected South African Wastewaters 2015-2016: Emergence of the Novel GII.17.

    PubMed

    Mabasa, V V; Meno, K D; Taylor, M B; Mans, Janet

    2017-08-04

    Norovirus (NoV) GII.4 is the predominant genotype associated with gastroenteritis pandemics and new strains emerge every 2-3 years. Between 2008 and 2011, environmental studies in South Africa (SA) reported NoVs in 63% of the sewage-polluted river water samples. The aim of this study was to assess whether wastewater samples could be used for routine surveillance of NoVs, including GII.4 variants. From April 2015 to March 2016, raw sewage and effluent water samples were collected monthly from five wastewater treatment plants in SA. A total of 108 samples were screened for NoV GI and GII using real-time RT-qPCR. Overall 72.2% (78/108) of samples tested positive for NoVs with 4.6% (5/108) GI, 31.5% (34/108) GII and 36.1% (39/108) GI + GII strains being detected. Norovirus concentrations ranged from 1.02 × 10(2) to 3.41 × 10(6) genome copies/litre for GI and 5.00 × 10(3) to 1.31 × 10(6) genome copies/litre for GII. Sixteen NoV genotypes (GI.2, GI.3, GI.4, GI.5, GI.6, GII.2, GII.3, GII.4, GII.7, GII.9, GII.10, GII.14, GII.16, GII.17, GII.20, and GII.21) were identified. Norovirus GII.2 and GII.17 co-dominated and the majority of GII.17 strains clustered with the novel Kawasaki 2014 variant. Sewage surveillance facilitated detection of Kawasaki 2014 in SA, which to date has not been detected with surveillance in children with gastroenteritis <5 years of age. Combined surveillance in the clinical setting and environment appears to be a valuable strategy to monitor emergence of NoV strains in countries that lack NoV outbreak surveillance.

  18. Investigation of norovirus occurrence in groundwater in metropolitan Seoul, Korea.

    PubMed

    Lee, Heetae; Kim, Misoon; Lee, Jung Eun; Lim, Miyoung; Kim, Minjung; Kim, Ju-Mi; Jheong, Weon-Hwa; Kim, Jongmin; Ko, GwangPyo

    2011-05-01

    Groundwater is an important source of drinking and household water worldwide. Hence, the quality of groundwater is very important for preventing waterborne disease outbreaks and should be properly monitored. This study investigated the prevalence of waterborne viruses and fecal indicators in groundwater in metropolitan Seoul and Gyeonggi province, South Korea. A total of 116 samples of groundwater were taken using NanoCeram filters during both summer (June to August) and fall-winter seasons (October to December) in 2008. Among 71 sampling sites, 28 (48.3%) and 18 (35.3%) were positive for norovirus (NoV) from the summer and fall-winter season, respectively. The identified genotypes of NoV include GI-1, 4, 8, 9 and GII-4, 10, 11 (or 17), 13, 15 (or 16). None of fecal indicators was significantly correlated with NoV in groundwater. Among the tested fecal indicators, somatic coliphage (95.3%) showed an excellent true-negative rate of NoV occurrence. The combination of chemical, microbial and viral indicators increased the positive predictive value (50-100%). This study demonstrated a high prevalence of NoV in groundwater in metropolitan Seoul areas and characterized the positive and negative predictive values of a fecal indicator for predicting NoV prevalence.

  19. Serial Foodborne Norovirus Outbreaks Associated with Multiple Genotypes

    PubMed Central

    Huang, Jianwei; Xu, Xuerong; Weng, Qinyun; Hong, Huarong; Guo, Zhinan; He, Shuizhen; Niu, Jianjun

    2013-01-01

    Noroviruses (NoV) have been recognized as an important pathogen associated with acute gastroenteritis worldwide during the past three decades. In the spring of 2012, a series of foodborne outbreaks in tourist groups were reported to Xiamen Center for Disease Control and Prevention, Xiamen, Fujian province, China. Among a total of 268 tourists in 7 groups, the prevalence rate of acute gastroenteritis was 16.0% (43/268). Twenty-three feces or anal swabs were collected for laboratory tests of causative agents, no bacterial pathogen was identified, while 22 of them were positive for NoV RNA. In addition, thirteen NoV fragments were recovered from positive specimens and sequenced, belonging to five genotypes such as GI.3, GI.4, GII.4, GII.6, and GII.14, respectively. However, NoV fragments obtained from locally infected patients showed distinct genotypes. Therefore, epidemiological investigation and laboratory analyses demonstrated that the serial foodborne NoV outbreaks in tourists were co-infection of multiple genotypes induced acute gastroenteritis linked to a restaurant. PMID:23667602

  20. Serial foodborne norovirus outbreaks associated with multiple genotypes.

    PubMed

    Huang, Jianwei; Xu, Xuerong; Weng, Qinyun; Hong, Huarong; Guo, Zhinan; He, Shuizhen; Niu, Jianjun

    2013-01-01

    Noroviruses (NoV) have been recognized as an important pathogen associated with acute gastroenteritis worldwide during the past three decades. In the spring of 2012, a series of foodborne outbreaks in tourist groups were reported to Xiamen Center for Disease Control and Prevention, Xiamen, Fujian province, China. Among a total of 268 tourists in 7 groups, the prevalence rate of acute gastroenteritis was 16.0% (43/268). Twenty-three feces or anal swabs were collected for laboratory tests of causative agents, no bacterial pathogen was identified, while 22 of them were positive for NoV RNA. In addition, thirteen NoV fragments were recovered from positive specimens and sequenced, belonging to five genotypes such as GI.3, GI.4, GII.4, GII.6, and GII.14, respectively. However, NoV fragments obtained from locally infected patients showed distinct genotypes. Therefore, epidemiological investigation and laboratory analyses demonstrated that the serial foodborne NoV outbreaks in tourists were co-infection of multiple genotypes induced acute gastroenteritis linked to a restaurant.

  1. Immunomagnetic separation combined with RT-qPCR for determining the efficacy of disinfectants against human noroviruses.

    PubMed

    Liu, Pengbo; Kim, Myung; Schlesinger, David; Kranz, Christine; Ha, Sangdo; Ha, Jeehyoung; Slauch, James; Baek, Seungbum; Moe, Christine

    2015-01-01

    Little is known about the effectiveness of disinfectants against human noroviruses (NoV) partially because human NoV cannot be routinely cultured in laboratory. The objective of this study was to develop a NoV monoclonal antibody-conjugated immunomagnetic separation (IMS) procedure combined with real-time reverse transcription polymerase chain reaction (RT-qPCR) assays to study the in vitro efficacy of disinfectants against human NoV. Monoclonal antibodies against Norwalk virus (NV, GI.1) and NoV GII.4 were produced using unique NoV capsid proteins, and the antibodies were conjugated to magnetic Dynalbeads. The immunomagnetic beads were used to simultaneously capture intact NoV in samples and effectively remove PCR inhibitors. We examined the efficacy of ethanol, sodium hypochlorite, nine commercially available disinfectants, and one prototype disinfectant using the IMS/RT-qPCR. The sensitivity of this procedure was approximately 100 virus particles for both the NV and GII.4 viruses. The average log reductions in in vitro activities varied between disinfectants. The prototype disinfectant produced an average 3.19-log reduction in NV and a 1.38-log reduction in GII.4. The prototype disinfectant is promising of inactivating NoV. This method can be used to evaluate in vitro activity of disinfectants against human NoV. The IMS/RT-qPCR method is promising as an effective method to remove PCR inhibitors in disinfectants and enable the evaluation of the efficacy of disinfectants. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  2. Norovirus infections in asymptomatic food handlers in elementary schools without norovirus outbreaks in some regions of Incheon, Korea.

    PubMed

    Yu, Jun-Hwan; Kim, Na-Yeon; Lee, Eun-Jung; Jeon, In-Sang

    2011-06-01

    Norovirus (NV) has caused large outbreaks of gastroenteritis in schools. Studies of NV epidemiology in schools related to NV outbreaks have been frequently reported. However, reports of that in schools without outbreaks are not found. Presently, NV molecular epidemiology surveillance was carried out in asymptomatic food handlers working at nonoutbreak elementary schools in Incheon, Korea, in March, April and December, 2009. NV prevalence was examined by real-time reverse transcription-PCR (RT-PCR) and the positive products were re-evaluated by conventional RT-PCR for sequencing. Fecal samples (n = 776) were collected from 776 food handlers in 60 schools. NV was detected in 26 of them (3.4%). Of these, 17 (65%) were positive for NV GII and 10 (38%) were positive for NV GI. Of the 26 samples, 19 were positive by conventional RT-PCR. Sequencing of these 19 strains revealed GII/4 (n = 5), GI/6 (n = 3), GI/14 (n = 2), GII/8 (n = 2), GI/2 (n = 2), GI/10 (n = 1), GII/1 (n = 1), GII/3 (n = 1), GII/7 (n = 1), and GII/16 (n = 1). In this survey, the food handler population unrelated to NV outbreaks was found to normally contain asymptomatic carriers of NV. The excretion of NV from asymptomatic food handlers should be an infection source of NV outbreaks.

  3. Crystallography of a Lewis-Binding Norovirus, Elucidation of Strain-Specificity to the Polymorphic Human Histo-Blood Group Antigens

    PubMed Central

    Xia, Ming; Hao, Ning; Zhang, Xuejun C.; Huang, Pengwei; Jiang, Xi; Li, Xuemei; Rao, Zihe

    2011-01-01

    Noroviruses, an important cause of acute gastroenteritis in humans, recognize the histo-blood group antigens (HBGAs) as host susceptible factors in a strain-specific manner. The crystal structures of the HBGA-binding interfaces of two A/B/H-binding noroviruses, the prototype Norwalk virus (GI.1) and a predominant GII.4 strain (VA387), have been elucidated. In this study we determined the crystal structures of the P domain protein of the first Lewis-binding norovirus (VA207, GII.9) that has a distinct binding property from those of Norwalk virus and VA387. Co-crystallization of the VA207 P dimer with Ley or sialyl Lex tetrasaccharides showed that VA207 interacts with these antigens through a common site found on the VA387 P protein which is highly conserved among most GII noroviruses. However, the HBGA-binding site of VA207 targeted at the Lewis antigens through the α-1, 3 fucose (the Lewis epitope) as major and the β-N-acetyl glucosamine of the precursor as minor interacting sites. This completely differs from the binding mode of VA387 and Norwalk virus that target at the secretor epitopes. Binding pocket of VA207 is formed by seven amino acids, of which five residues build up the core structure that is essential for the basic binding function, while the other two are involved in strain-specificity. Our results elucidate for the first time the genetic and structural basis of strain-specificity by a direct comparison of two genetically related noroviruses in their interaction with different HBGAs. The results provide insight into the complex interaction between the diverse noroviruses and the polymorphic HBGAs and highlight the role of human HBGA as a critical factor in norovirus evolution. PMID:21811409

  4. Infection control for norovirus

    PubMed Central

    Barclay, L.; Park, G. W.; Vega, E.; Hall, A.; Parashar, U.; Vinjé, J.; Lopman, B.

    2015-01-01

    Norovirus infections are notoriously difficult to prevent and control, owing to their low infectious dose, high shedding titre, and environmental stability. The virus can spread through multiple transmission routes, of which person-to-person and foodborne are the most important. Recent advances in molecular diagnostics have helped to establish norovirus as the most common cause of sporadic gastroenteritis and the most common cause of outbreaks of acute gastroenteritis across all ages. In this article, we review the epidemiology and virology of noroviruses, and prevention and control guidelines, with a focus on the principles of disinfection and decontamination. Outbreak management relies on sound infection control principles, including hand hygiene, limiting exposure to infectious individuals, and thorough environmental decontamination. Ideally, all infection control recommendations would rely on empirical evidence, but a number of challenges, including the inability to culture noroviruses in the laboratory and the challenges of outbreak management in complex environments, has made it difficult to garner clear evidence of efficacy in certain areas of infection control. New experimental data on cultivable surrogates for human norovirus and on environmental survivability and relative resistance to commonly used disinfectants are providing new insights for further refinining disinfection practices. Finally, clinical trials are underway to evaluate the efficacy of vaccines, which may shift the current infection control principles to more targeted interventions. PMID:24813073

  5. Recent advances in understanding noroviruses

    PubMed Central

    Bartnicki, Eric; Cunha, Juliana Bragazzi; Kolawole, Abimbola O.; Wobus, Christiane E.

    2017-01-01

    Noroviruses are the leading cause of acute gastroenteritis around the world. An individual living in the United States is estimated to develop norovirus infection five times in his or her lifetime. Despite this, there is currently no antiviral or vaccine to combat the infection, in large part because of the historical lack of cell culture and small animal models. However, the last few years of norovirus research were marked by a number of ground-breaking advances that have overcome technical barriers and uncovered novel aspects of norovirus biology. Foremost among them was the development of two different in vitro culture systems for human noroviruses. Underappreciated was the notion that noroviruses infect cells of the immune system as well as epithelial cells within the gastrointestinal tract and that human norovirus infection of enterocytes requires or is promoted by the presence of bile acids. Furthermore, two proteinaceous receptors are now recognized for murine norovirus, marking the first discovery of a functional receptor for any norovirus. Recent work further points to a role for certain bacteria, including those found in the gut microbiome, as potential modulators of norovirus infection in the host, emphasizing the importance of interactions with organisms from other kingdoms of life for viral pathogenesis. Lastly, we will highlight the adaptation of drop-based microfluidics to norovirus research, as this technology has the potential to reveal novel insights into virus evolution. This review aims to summarize these new findings while also including possible future directions. PMID:28163914

  6. Norovirus gene expression and replication.

    PubMed

    Thorne, Lucy G; Goodfellow, Ian G

    2014-02-01

    Noroviruses are small, positive-sense RNA viruses within the family Caliciviridae, and are now accepted widely as a major cause of acute gastroenteritis in both developed and developing countries. Despite their impact, our understanding of the life cycle of noroviruses has lagged behind that of other RNA viruses due to the inability to culture human noroviruses (HuNVs). Our knowledge of norovirus biology has improved significantly over the past decade as a result of numerous technological advances. The use of a HuNV replicon, improved biochemical and cell-based assays, combined with the discovery of a murine norovirus capable of replication in cell culture, has improved greatly our understanding of the molecular mechanisms of norovirus genome translation and replication, as well as the interaction with host cell processes. In this review, the current state of knowledge of the intracellular life of noroviruses is discussed with particular emphasis on the mechanisms of viral gene expression and viral genome replication.

  7. Reporting and Surveillance for Norovirus Outbreaks

    MedlinePlus

    ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology Reporting and Surveillance for Norovirus Recommend on Facebook ... Norovirus Infection, National Institutes of Health NoroCORE Food Virology File Formats Help: How do I view different ...

  8. The Application of New Molecular Methods in the Investigation of a Waterborne Outbreak of Norovirus in Denmark, 2012

    PubMed Central

    Schultz, Anna Charlotte; Fonager, Jannik; Ethelberg, Steen; Dalgaard, Camilla; Adelhardt, Marianne; Engberg, Jørgen H.; Fischer, Thea Kølsen; Lassen, Sofie Gillesberg

    2014-01-01

    In December 2012, an outbreak of acute gastrointestinal illness occurred in a geographical distinct area in Denmark covering 368 households. A combined microbiological, epidemiological and environmental investigation was initiated to understand the outbreak magnitude, pathogen(s) and vehicle in order to control the outbreak. Norovirus GII.4 New Orleans 2009 variant was detected in 15 of 17 individual stool samples from 14 households. Norovirus genomic material from water samples was detected and quantified and sequencing of longer parts of the viral capsid region (>1000 nt) were applied to patient and water samples. All five purposely selected water samples tested positive for norovirus GII in levels up to 1.8×104 genomic units per 200 ml. Identical norovirus sequences were found in all 5 sequenced stool samples and 1 sequenced water sample, a second sequenced water sample showed 1 nt (<0.1%) difference. In a cohort study, including 256 participants, cases were defined as residents of the area experiencing diarrhoea or vomiting onset on 12–14 December 2012. We found an attack rate of 51%. Being a case was associated with drinking tap-water on 12–13 December (relative risk = 6.0, 95%CI: 1.6–22) and a dose-response relation for the mean glasses of tap-water consumed was observed. Environmental investigations suggested contamination from a sewage pipe to the drinking water due to fall in pressure during water supply system renovations. The combined microbiological, epidemiological and environmental investigations strongly indicates the outbreak was caused by norovirus contamination of the water supply system. PMID:25222495

  9. Transfer of noroviruses between fingers and fomites and food products.

    PubMed

    Tuladhar, Era; Hazeleger, Wilma C; Koopmans, Marion; Zwietering, Marcel H; Duizer, Erwin; Beumer, Rijkelt R

    2013-11-01

    Human norovirus (NoV) contaminated hands are important routes for transmission. Quantitative data on transfer during contact with surfaces and food are scarce but necessary for a quantitative risk assessment. Therefore, transfer of MNV1 and human NoVs GI.4 and GII.4 was studied by artificially contaminating human finger pads, followed by pressing on stainless steel and Trespa® surfaces and also on whole tomatoes and cucumber slices. In addition, clean finger pads were pressed on artificially contaminated stainless steel and Trespa® surfaces. The transfers were performed at a pressure of 0.8-1.9 kg/cm(2) for approximately 2s up to 7 sequential transfers either to carriers or to food products. MNV1 infectivity transfer from finger pads to stainless steel ranged from 13 ± 16% on the first to 0.003 ± 0.009% on the sixth transfer on immediate transfer. After 10 min of drying, transfer was reduced to 0.1 ± 0.2% on the first transfer to 0.013 ± 0.023% on the fifth transfer. MNV1 infectivity transfer from stainless steel and Trespa® to finger pads after 40 min of drying was 2.0 ± 2.0% and 4.0 ± 5.0% respectively. MNV1 infectivity was transferred 7 ± 8% to cucumber slices and 0.3 ± 0.5% to tomatoes after 10 min of drying, where the higher transfer to cucumber was probably due to the higher moisture content of the cucumber slices. Similar results were found for NoVs GI.4 and GII.4 transfers measured in PCR units. The results indicate that transfer of the virus is possible even after the virus is dried on the surface of hands or carriers. Furthermore, the role of fingers in transmission of NoVs was quantified and these data can be useful in risk assessment models and to establish target levels for efficacy of transmission intervention methods. © 2013 Elsevier B.V. All rights reserved.

  10. Virucidal Activity of Fogged Chlorine Dioxide- and Hydrogen Peroxide-Based Disinfectants against Human Norovirus and Its Surrogate, Feline Calicivirus, on Hard-to-Reach Surfaces.

    PubMed

    Montazeri, Naim; Manuel, Clyde; Moorman, Eric; Khatiwada, Janak R; Williams, Leonard L; Jaykus, Lee-Ann

    2017-01-01

    Human norovirus (NoV) is the leading cause of foodborne illnesses in the United States. Norovirus is shed in high numbers in the feces and vomitous of infected individuals. Contact surfaces contaminated with bodily fluids harboring infectious virus particles serve as vehicles for pathogen transmission. Environmental stability of NoV and its resistance to many conventional disinfectants necessitate effective inactivation strategies to control the spread of virus. We investigated the efficacy of two commercial disinfectants, hydrogen peroxide (7.5%) and a chlorine dioxide (0.2%)-surfactant-based product using a fogging delivery system against human NoV GI.6 and GII.4 Sydney strains as well as the cultivable surrogate, feline calicivirus (FCV) dried on stainless steel coupons. Log10 reductions in human NoV and FCV were calculated utilizing RNase RT-qPCR and infectivity (plaque) assay, respectively. An improved antiviral activity of hydrogen peroxide as a function of disinfectant formulation concentration in the atmosphere was observed against both GII.4 and FCV. At 12.4 ml/m(3), hydrogen peroxide achieved a respective 2.5 ± 0.1 and 2.7 ± 0.3 log10 reduction in GI.6 and GII.4 NoV genome copies, and a 4.3 ± 0.1 log10 reduction in infectious FCV within 5 min. At the same disinfectant formulation concentration, chlorine dioxide-surfactant-based product resulted in a respective 1.7 ± 0.2, 0.6 ± 0.0, and 2.4 ± 0.2 log10 reduction in GI.6, GII.4, and FCV within 10 min; however, increasing the disinfectant formulation concentration to 15.9 ml/m(3) negatively impacted its efficacy. Fogging uniformly delivered the disinfectants throughout the room, and effectively decontaminated viruses on hard-to-reach surfaces. Hydrogen peroxide delivered by fog showed promising virucidal activity against FCV by meeting the United States EPA 4-log10 reduction criteria for an anti-noroviral disinfectant; however, fogged chlorine dioxide-surfactant-based product did not achieve a 4-log10

  11. Virucidal Activity of Fogged Chlorine Dioxide- and Hydrogen Peroxide-Based Disinfectants against Human Norovirus and Its Surrogate, Feline Calicivirus, on Hard-to-Reach Surfaces

    PubMed Central

    Montazeri, Naim; Manuel, Clyde; Moorman, Eric; Khatiwada, Janak R.; Williams, Leonard L.; Jaykus, Lee-Ann

    2017-01-01

    Human norovirus (NoV) is the leading cause of foodborne illnesses in the United States. Norovirus is shed in high numbers in the feces and vomitous of infected individuals. Contact surfaces contaminated with bodily fluids harboring infectious virus particles serve as vehicles for pathogen transmission. Environmental stability of NoV and its resistance to many conventional disinfectants necessitate effective inactivation strategies to control the spread of virus. We investigated the efficacy of two commercial disinfectants, hydrogen peroxide (7.5%) and a chlorine dioxide (0.2%)-surfactant-based product using a fogging delivery system against human NoV GI.6 and GII.4 Sydney strains as well as the cultivable surrogate, feline calicivirus (FCV) dried on stainless steel coupons. Log10 reductions in human NoV and FCV were calculated utilizing RNase RT-qPCR and infectivity (plaque) assay, respectively. An improved antiviral activity of hydrogen peroxide as a function of disinfectant formulation concentration in the atmosphere was observed against both GII.4 and FCV. At 12.4 ml/m3, hydrogen peroxide achieved a respective 2.5 ± 0.1 and 2.7 ± 0.3 log10 reduction in GI.6 and GII.4 NoV genome copies, and a 4.3 ± 0.1 log10 reduction in infectious FCV within 5 min. At the same disinfectant formulation concentration, chlorine dioxide-surfactant-based product resulted in a respective 1.7 ± 0.2, 0.6 ± 0.0, and 2.4 ± 0.2 log10 reduction in GI.6, GII.4, and FCV within 10 min; however, increasing the disinfectant formulation concentration to 15.9 ml/m3 negatively impacted its efficacy. Fogging uniformly delivered the disinfectants throughout the room, and effectively decontaminated viruses on hard-to-reach surfaces. Hydrogen peroxide delivered by fog showed promising virucidal activity against FCV by meeting the United States EPA 4-log10 reduction criteria for an anti-noroviral disinfectant; however, fogged chlorine dioxide-surfactant-based product did not achieve a 4-log10

  12. Emergence of norovirus GI.2 outbreaks in military camps in Singapore.

    PubMed

    Ho, Zheng Jie Marc; Vithia, Gunalan; Ng, Ching Ging; Maurer-Stroh, Sebastian; Tan, Clive M; Loh, Jimmy; Lin, Tzer Pin Raymond; Lee, Jian Ming Vernon

    2015-02-01

    Simultaneous acute gastroenteritis (AGE) outbreaks occurred at two military camps. This study details the epidemiological findings, explores possible origins, and discusses preventive measures. Investigations included attack rate surveys, symptom surveys, hygiene inspections, and the testing of water, food, and stool samples. DNA/RNA was extracted from stool samples and amplified via real-time reverse transcription PCR (RT-PCR). Partial and full-length capsid nucleotide sequences were obtained, phylogenetic relationships inferred, and homology modelling of antigenic sites performed. The military outbreaks involved 775 persons and were preceded by two AGE outbreaks at restaurants in the local community. The outbreak was longer and larger in the bigger camp (21 days, attack rate 15.0%) than the smaller camp (6 days, attack rate 8.3%). Of 198 stool samples, norovirus GI.2 was detected in 32.5% (larger camp) and 28.6% (smaller camp). These were essentially identical to preceding community outbreaks. Antigenic site homology modelling also showed differences between identified and more common AGE outbreak strains (norovirus GII.4). Differences observed highlight difficulties in controlling person-to-person outbreaks among large groups in close proximity (e.g., military trainees). Distinct differences in antigenic sites may have contributed to increased immunological susceptibility of the soldiers to infection. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Nucleotidylylation of the VPg Protein of a Human Norovirus by its Proteinase-Polymerase Precursor Protein

    PubMed Central

    Belliot, Gaël; Sosnovtsev, Stanislav V.; Chang, Kyeong-Ok; McPhie, Peter; Green, Kim Y.

    2008-01-01

    Caliciviruses have a positive strand RNA genome covalently-linked at the 5’-end to a small protein, VPg. This study examined the biochemical modification of VPg by the ProPol form of the polymerase of human norovirus strain MD145 (GII.4). Recombinant norovirus VPg was shown to be nucleotidylylated in the presence of Mn2+ by MD145 ProPol. Phosphodiesterase I treatment of the nucleotidylylated VPg released the incorporated UMP, which was consistent with linkage of RNA to VPg via a phosphodiester bond. Mutagenesis analysis of VPg identified Tyrosine 27 as the target amino acid for this linkage, and suggested that VPg conformation was important for the reaction. Nucleotidylylation was inefficient in the presence of Mg2+; however the addition of full- and subgenomic-length MD145 RNA transcripts led to a marked enhancement of the nucleotidylylation efficiency in the presence of this divalent cation. Furthermore, evidence was found for the presence of an RNA element near the 3’-end of the polyadenylated genome that enhanced the efficiency of nucleotidylylation in the presence of Mg2+. PMID:18234264

  14. Nucleotidylylation of the VPg protein of a human norovirus by its proteinase-polymerase precursor protein.

    PubMed

    Belliot, Gaël; Sosnovtsev, Stanislav V; Chang, Kyeong-Ok; McPhie, Peter; Green, Kim Y

    2008-04-25

    Caliciviruses have a positive strand RNA genome covalently-linked at the 5'-end to a small protein, VPg. This study examined the biochemical modification of VPg by the ProPol form of the polymerase of human norovirus strain MD145 (GII.4). Recombinant norovirus VPg was shown to be nucleotidylylated in the presence of Mn2+ by MD145 ProPol. Phosphodiesterase I treatment of the nucleotidylylated VPg released the incorporated UMP, which was consistent with linkage of RNA to VPg via a phosphodiester bond. Mutagenesis analysis of VPg identified Tyrosine 27 as the target amino acid for this linkage, and suggested that VPg conformation was important for the reaction. Nucleotidylylation was inefficient in the presence of Mg2+; however the addition of full- and subgenomic-length MD145 RNA transcripts led to a marked enhancement of the nucleotidylylation efficiency in the presence of this divalent cation. Furthermore, evidence was found for the presence of an RNA element near the 3'-end of the polyadenylated genome that enhanced the efficiency of nucleotidylylation in the presence of Mg2+.

  15. Hospital-acquired rotavirus and norovirus acute gastroenteritis in a pediatric unit, in 2014-2015.

    PubMed

    Valentini, Diletta; Ianiro, Giovanni; Di Bartolo, Ilaria; Di Camillo, Chiara; Boccuzzi, Elena; Vittucci, Anna C; Ruggeri, Franco M; Monini, Marina

    2017-10-01

    The occurrence of hospital-acquired acute gastroenteritis (AGE) is a major concern for public health. RotavirusA (RVA) and norovirus (NoV) are common causes of viral AGE in the pediatric population, and their role in nosocomial infections has been proven, remaining poorly investigated. To investigate RVA and NoV in hospital-acquired AGE, 55 stool samples from children with nosocomial AGE were collected between May 2014 and May 2015. To evaluate virus spreading routes, 51 environmental swabs were collected from staff and patients' rooms. Stools were tested for both RVA and NoV RNA by reverse-transcription-PCR. Nucleotide sequencing and phylogenetic analysis were performed to characterize the viruses. Forty-seven of 55 cases analyzed resulted positive for RVA. The predominant genotype was G4P[8] (18/55) followed by G1P[8] (14/55). Mixed RVA infections were also detected (7/55). Twenty-two samples were positive for NoV, and GII.4 was revealed to be the predominant genotype. Seventeen samples were positive for both RVA and NoV. This study aimed to evaluate the burden of norovirus and rotavirus nosocomial AGE, contributing to identify the environment source of infections and to activate effective strategies for intervention. The reduction in nosocomial AGE cases is an important aspect, considered the worsened disease course in transplant, cancer, and intensive care unit inpatients. © 2017 Wiley Periodicals, Inc.

  16. A Gnotobiotic Pig Model for Determining Human Norovirus Inactivation by High-Pressure Processing.

    PubMed

    Lou, Fangfei; Ye, Mu; Ma, Yuanmei; Li, Xinhui; DiCaprio, Erin; Chen, Haiqiang; Krakowka, Steven; Hughes, John; Kingsley, David; Li, Jianrong

    2015-10-01

    Human norovirus (NoV) is responsible for over 90% of outbreaks of acute nonbacterial gastroenteritis worldwide and accounts for 60% of cases of foodborne illness in the United States. Currently, the infectivity of human NoVs is poorly understood due to the lack of a cell culture system. In this study, we determined the survival of a human NoV genogroup II, genotype 4 (GII.4) strain in seeded oyster homogenates after high-pressure processing (HPP) using a novel receptor binding assay and a gnotobiotic pig model. Pressure conditions of 350 MPa at 0°C for 2 min led to a 3.7-log10 reduction in the number of viral RNA copies in oysters, as measured by the porcine gastric mucin-conjugated magnetic bead (PGM-MB) binding assay and real-time RT-PCR, whereas pressure conditions of 350 MPa at 35°C for 2 min achieved only a 1-log10 reduction in the number of RNA copies. Newborn gnotobiotic piglets orally fed oyster homogenate treated at 350 MPa and 0°C for 2 min did not have viral RNA shedding in feces, histologic lesions, or viral replication in the small intestine. In contrast, gnotobiotic piglets fed oysters treated at 350 MPa and 35°C for 2 min had high levels of viral shedding in feces and exhibited significant histologic lesions and viral replication in the small intestine. Collectively, these data demonstrate that (i) human NoV survival estimated by an in vitro PGM-MB virus binding assay is consistent with the infectivity determined by an in vivo gnotobiotic piglet model and (ii) HPP is capable of inactivating a human NoV GII.4 strain at commercially acceptable pressure levels. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  17. Exploration of the metal coordination region of concanavalin A for its interaction with human norovirus.

    PubMed

    Kim, Duwoon; Lee, Hee-Min; Oh, Kyung-Seo; Ki, Ah Young; Protzman, Rachael A; Kim, Dongkyun; Choi, Jong-Soon; Kim, Min Ji; Kim, Sung Hyun; Vaidya, Bipin; Lee, Seung Jae; Kwon, Joseph

    2017-06-01

    Rapid methods for the detection and clinical treatment of human norovirus (HuNoV) are needed to control foodborne disease outbreaks, but reliable techniques that are fast and sensitive enough to detect small amounts of HuNoV in food and aquatic environments are not yet available. We explore the interactions between HuNoV and concanavalin A (Con A), which could facilitate the development of a sensitive detection tool for HuNoV. Biophysical studies including hydrogen/deuterium exchange (HDX) mass spectrometry and surface plasmon resonance (SPR) revealed that when the metal coordinated region of Con A, which spans Asp16 to His24, is converted to nine alanine residues (mCon A(MCR)), the affinity for HuNoV (GII.4) diminishes, demonstrating that this Ca(2+) and Mn(2+) coordinated region is responsible for the observed virus-protein interaction. The mutated carbohydrate binding region of Con A (mCon A(CBR)) does not affect binding affinity significantly, indicating that MCR of Con A is a major region of interaction to HuNoV (GII.4). The results further contribute to the development of a HuNoV concentration tool, Con A-immobilized polyacrylate beads (Con A-PAB), for rapid detection of genotypes from genogroups I and II (GI and GII). This method offers many advantages over currently available methods, including a short concentration time. HuNov (GI and GII) can be detected in just 15 min with 90% recovery through Con A-PAB application. In addition, this method can be used over a wide range of pH values (pH 3.0 - 10.0). Overall, this rapid and sensitive detection of HuNoV (GI and GII) will aid in the prevention of virus transmission pathways, and the method developed here may have applicability for other foodborne viral infections.

  18. Inactivation of human norovirus in contaminated oysters and clams by high hydrostatic pressure.

    PubMed

    Ye, Mu; Li, Xinhui; Kingsley, David H; Jiang, Xi; Chen, Haiqiang

    2014-04-01

    Human norovirus (NoV) is the most frequent causative agent of food-borne disease associated with shellfish consumption. In this study, the effect of high hydrostatic pressure (HHP) on inactivation of NoV was determined. Genogroup I.1 (GI.1) or genogroup II.4 (GII.4) NoV was inoculated into oyster homogenates and treated at 300 to 600 MPa at 25, 6, and 1°C for 5 min. After HHP, samples were treated with RNase and viral particles were extracted with porcine gastric mucin (PGM)-conjugated magnetic beads (PGM-MBs). Viral RNA was then quantified by real-time reverse transcription (RT)-PCR. Since PGM contains histo-blood group-like antigens, which can act as receptors for NoV, deficiency for binding to PGM is an indication of loss of infectivity of NoV. After binding to PGM-MBs, RT-PCR-detectable NoV RNA in oysters was reduced by 0.4 to >4 log10 by HHP at 300 to 600 MPa. The GI.1 NoV was more resistant to HHP than the GII.4 NoV (P < 0.05). HHP at lower temperatures significantly enhanced the inactivation of NoV in oysters (P < 0.05). Pressure treatment was also conducted for clam homogenates. Treatment at 450 MPa at 1°C achieved a >4 log10 reduction of GI.1 NoV in both oyster and clam homogenates. It is therefore concluded that HHP could be applied as a potential intervention for inactivating NoV in raw shellfish. The method of pretreatment of samples with RNase, extraction of viral particles using PGM-MB binding, and quantification of viral RNA using RT-PCR can be explored as a practical means of distinguishing between infectious and noninfectious NoV.

  19. A Gnotobiotic Pig Model for Determining Human Norovirus Inactivation by High-Pressure Processing

    PubMed Central

    Lou, Fangfei; Ye, Mu; Ma, Yuanmei; Li, Xinhui; DiCaprio, Erin; Chen, Haiqiang; Krakowka, Steven; Hughes, John; Kingsley, David

    2015-01-01

    Human norovirus (NoV) is responsible for over 90% of outbreaks of acute nonbacterial gastroenteritis worldwide and accounts for 60% of cases of foodborne illness in the United States. Currently, the infectivity of human NoVs is poorly understood due to the lack of a cell culture system. In this study, we determined the survival of a human NoV genogroup II, genotype 4 (GII.4) strain in seeded oyster homogenates after high-pressure processing (HPP) using a novel receptor binding assay and a gnotobiotic pig model. Pressure conditions of 350 MPa at 0°C for 2 min led to a 3.7-log10 reduction in the number of viral RNA copies in oysters, as measured by the porcine gastric mucin-conjugated magnetic bead (PGM-MB) binding assay and real-time RT-PCR, whereas pressure conditions of 350 MPa at 35°C for 2 min achieved only a 1-log10 reduction in the number of RNA copies. Newborn gnotobiotic piglets orally fed oyster homogenate treated at 350 MPa and 0°C for 2 min did not have viral RNA shedding in feces, histologic lesions, or viral replication in the small intestine. In contrast, gnotobiotic piglets fed oysters treated at 350 MPa and 35°C for 2 min had high levels of viral shedding in feces and exhibited significant histologic lesions and viral replication in the small intestine. Collectively, these data demonstrate that (i) human NoV survival estimated by an in vitro PGM-MB virus binding assay is consistent with the infectivity determined by an in vivo gnotobiotic piglet model and (ii) HPP is capable of inactivating a human NoV GII.4 strain at commercially acceptable pressure levels. PMID:26187968

  20. Vaccines against norovirus: state of the art trials in children and adults.

    PubMed

    Baehner, F; Bogaerts, H; Goodwin, R

    2016-12-01

    Noroviruses (NoVs), a group of nonenveloped, single-stranded RNA viruses belonging to the Caliciviridae family, are the leading cause worldwide of acute infectious gastroenteritis. Serious and eventual fatal outcomes may be observed in at-risk populations such as the very young or older adults, especially in those with underlying diseases. NoVs are highly infectious, with a low number of virus particles causing infection, and they are highly resistant to environmental conditions. NoVs have multiple routes of transmission including faecal-oral, aerosolized vomitus, person to person and via contaminated surfaces or food and water. NoVs can cause frequent and dramatic outbreaks where people congregate in close quarters such as hospitals, long-term care facilities, cruise liners and military barracks and ships. Of the seven NoV genogroups, human disease is most frequently caused by genogroups I and II, although genogroup IV has also been associated with illness. The absence of reliable, high-yield cell culture systems or animal models has steered the development of vaccines towards nonreplicating recombinant capsid proteins including viruslike particles and the sub-virus-sized P particles. Takeda Vaccines is developing a candidate NoV vaccine formulation based on adjuvanted viruslike particles from the GI.1 genotype and a consensus GII.4 sequence derived from three natural GII.4 variants. Early clinical trial results show good tolerability and robust immune responses to both components. This approach is designed to induce broad protective immune responses in adults and children. Copyright © 2016 Takeda Pharmaceuticals International AG. Published by Elsevier Ltd.. All rights reserved.

  1. Host Genetic Factors Affect Susceptibility to Norovirus Infections in Burkina Faso

    PubMed Central

    Nordgren, Johan; Nitiema, Léon W.; Ouermi, Djeneba; Simpore, Jacques; Svensson, Lennart

    2013-01-01

    Norovirus (NoV) constitutes the second most common viral pathogen causing pediatric diarrhea after rotavirus. In Africa, diarrhea is a major health problem in children, and yet few studies have been performed regarding NoV. The association of histo-blood group antigens (HBGA) and susceptibility to NoV infection is well established in Caucasian populations with non-secretors being resistant to many common NoV strains. No study regarding HBGA and NoV susceptibility has yet been performed in Africa. We collected 309 stool and 208 saliva samples from diarrheal children in Ouagadougou, Burkina Faso; May 2009 to March 2010. NoV was detected using real-time PCR, and genotyped by sequencing. Saliva samples were ABO, Lewis and secretor phenotyped using in house ELISA assays. NoV was detected in 12% (n = 37) of the samples. The genotype diversity was unusually large; overall the 37 positive samples belonged to 14 genotypes. Only children <2 years of age were NoV positive and the GII.4 NoVs were more frequent in the late dry season (Jan-May). NoV infections were observed less in children with the secretor-negative phenotype or blood group A (OR 0.18; p = 0.012 and OR 0.31; p = 0.054; respectively), with two non-secretors infected with genotypes GII.7 and GII.4 respectively. Lewis-negative (Lea−b−) children, representing 32% of the study population, were susceptible to GII, but were not infected with any NoV GI. GII.4 strains preferentially infected children with blood group B whereas secretor-positive children with blood group O were infected with the largest variety of genotypes. This is the first study identifying host genetic factors associated with susceptibility to NoV in an African population, and suggests that while the non-secretor phenotype provides protection; the Lewis b antigen is not necessary for GII infection. PMID:23894502

  2. The molecular pathology of noroviruses.

    PubMed

    Karst, Stephanie M; Zhu, Shu; Goodfellow, Ian G

    2015-01-01

    Norovirus infection in humans typically results in acute gastroenteritis but may also occur in many animal species. Noroviruses are recognized as one of the most common causes of acute gastroenteritis in the world, being responsible for almost 20% of all cases. Despite their prevalence and impact, our knowledge of the norovirus life cycle and the pathological processes associated with norovirus-induced disease is limited. Whilst infection of the intestine is the norm, extraintestinal spread and associated pathologies have also been described. In addition, long-term chronic infections are now recognized as a significant cause of morbidity and mortality in the immunocompromised. This review aims to summarize the current state of knowledge with respect to norovirus pathology and the underlying mechanisms that have been characterized to date.

  3. Bacterial histo-blood group antigens contributing to genotype-dependent removal of human noroviruses with a microfiltration membrane.

    PubMed

    Amarasiri, Mohan; Hashiba, Satoshi; Miura, Takayuki; Nakagomi, Toyoko; Nakagomi, Osamu; Ishii, Satoshi; Okabe, Satoshi; Sano, Daisuke

    2016-05-15

    We demonstrated the genotype-dependent removal of human norovirus particles with a microfiltration (MF) membrane in the presence of bacteria bearing histo-blood group antigens (HBGAs). Three genotypes (GII.3, GII.4, and GII.6) of norovirus-like particles (NoVLPs) were mixed with three bacterial strains (Enterobacter sp. SENG-6, Escherichia coli O86:K61:B7, and Staphylococcus epidermidis), respectively, and the mixture was filtered with an MF membrane having a nominal pore size of 0.45 μm. All NoVLP genotypes were rejected by the MF membrane in the presence of Enterobacter sp. SENG-6, which excreted HBGAs as extracellular polymeric substances (EPS). This MF membrane removal of NoVLPs was not significant when EPS was removed from cells of Enterobacter sp. SENG-6. GII.6 NoVLP was not rejected with the MF membrane in the presence of E. coli O86:K61:B7, but the removal of EPS of E. coli O86:K61:B7 increased the removal efficiency due to the interaction of NoVLPs with the exposed B-antigen in lipopolysaccharide (LPS) of E. coli O86:K61:B7. No MF membrane removal of all three genotypes was observed when S. epidermidis, an HBGA-negative strain, was mixed with NoVLPs. These results demonstrate that the location of HBGAs on bacterial cells is an important factor in determining the genotype-dependent removal efficiency of norovirus particles with the MF membrane. The presence of HBGAs in mixed liquor suspended solids from a membrane bioreactor (MBR) pilot plant was confirmed by immune-transmission electron microscopy, which implies that bacterial HBGAs can contribute to the genotype-dependent removal of human noroviruses with MBR using MF membrane.

  4. Inactivation of a Foodborne Norovirus Outbreak Strain with Nonthermal Atmospheric Pressure Plasma

    PubMed Central

    Ahlfeld, Birte; Li, Yangfang; Boulaaba, Annika; Binder, Alfred; Schotte, Ulrich; Zimmermann, Julia L.; Morfill, Gregor

    2015-01-01

    ABSTRACT  Human norovirus (NoV) is the most frequent cause of epidemic nonbacterial acute gastroenteritis worldwide. We investigated the impact of nonthermal or cold atmospheric pressure plasma (CAPP) on the inactivation of a clinical human outbreak NoV, GII.4. Three different dilutions of a NoV-positive stool sample were prepared and subsequently treated with CAPP for various lengths of time, up to 15 min. NoV viral loads were quantified by quantitative real-time reverse transcription PCR (RT-qPCR). Increased CAPP treatment time led to increased NoV reduction; samples treated for the longest time had the lowest viral load. From the initial starting quantity of 2.36 × 104 genomic equivalents/ml, sample exposure to CAPP reduced this value by 1.23 log10 and 1.69 log10 genomic equivalents/ml after 10 and 15 min, respectively (P < 0.01). CAPP treatment of surfaces carrying a lower viral load reduced NoV by at least 1 log10 after CAPP exposure for 2 min (P < 0.05) and 1 min (P < 0.05), respectively. Our results suggest that NoV can be inactivated by CAPP treatment. The lack of cell culture assays prevents our ability to estimate infectivity. It is possible that some detectable, intact virus particles were rendered noninfectious. We conclude that CAPP treatment of surfaces may be a useful strategy to reduce the risk of NoV transmission in crowded environments. Importance  Human gastroenteritis is most frequently caused by noroviruses, which are spread person to person and via surfaces, often in facilities with crowds of people. Disinfection of surfaces that come into contact with infected humans is critical for the prevention of cross-contamination and further transmission of the virus. However, effective disinfection cannot be done easily in mass catering environments or health care facilities. We evaluated the efficacy of cold atmospheric pressure plasma, an innovative airborne disinfection method, on surfaces inoculated with norovirus. We used a clinically

  5. Pattern of Circulation of Norovirus GII Strains during Natural Infection

    PubMed Central

    Fobisong, Cajetan; Tah, Ferdinand; Lindh, Magnus; Nkuo-Akenji, Theresia; Bergström, Tomas

    2014-01-01

    Norovirus (NoV) is considered a major cause of nonbacterial gastroenteritis among people of all ages worldwide, but the natural course of infection is incompletely known. In this study, the pattern of circulation of NoVs was studied among 146 children and 137 adults in a small community in southwestern Cameroon. The participants provided monthly fecal samples during a year. NoV RNA was detected in at least one sample from 82 (29%) of the participants. The partial VP1 region could be sequenced in 36 NoV GII-positive samples. Three different genotypes were identified (GII.1, GII.4, and GII.17), with each genotype circulating within 2 to 3 months and reappearing after a relapse period of 2 to 3 months. Most infections occurred once, and 2 episodes at most within a year were detected. No difference in the frequency of NoV infection between children and adults was recorded. The same genotype was detected for a maximum of 2 consecutive months in 3 children only, suggesting that a less than 30-day duration of viral shedding in natural infection was common. Reinfection within a year with the same genotype was not observed, consistent with short-term homotypic immune protection. The study revealed that NoV strains are circulating with a limited duration of viral shedding both in the individuals and the population as part of their natural infection. The results also provide evidence of cross-protective immunity of limited duration between genotypes of the same genogroup. PMID:25274996

  6. Pattern of circulation of norovirus GII strains during natural infection.

    PubMed

    Ayukekbong, James Ayukepi; Fobisong, Cajetan; Tah, Ferdinand; Lindh, Magnus; Nkuo-Akenji, Theresia; Bergström, Tomas

    2014-12-01

    Norovirus (NoV) is considered a major cause of nonbacterial gastroenteritis among people of all ages worldwide, but the natural course of infection is incompletely known. In this study, the pattern of circulation of NoVs was studied among 146 children and 137 adults in a small community in southwestern Cameroon. The participants provided monthly fecal samples during a year. NoV RNA was detected in at least one sample from 82 (29%) of the participants. The partial VP1 region could be sequenced in 36 NoV GII-positive samples. Three different genotypes were identified (GII.1, GII.4, and GII.17), with each genotype circulating within 2 to 3 months and reappearing after a relapse period of 2 to 3 months. Most infections occurred once, and 2 episodes at most within a year were detected. No difference in the frequency of NoV infection between children and adults was recorded. The same genotype was detected for a maximum of 2 consecutive months in 3 children only, suggesting that a less than 30-day duration of viral shedding in natural infection was common. Reinfection within a year with the same genotype was not observed, consistent with short-term homotypic immune protection. The study revealed that NoV strains are circulating with a limited duration of viral shedding both in the individuals and the population as part of their natural infection. The results also provide evidence of cross-protective immunity of limited duration between genotypes of the same genogroup. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Nonnucleoside Inhibitors of Norovirus RNA Polymerase: Scaffolds for Rational Drug Design

    PubMed Central

    Eltahla, Auda A.; Lim, Kun Lee; Eden, John-Sebastian; Kelly, Andrew G.; Mackenzie, Jason M.

    2014-01-01

    Norovirus (NoV) is the leading cause of acute gastroenteritis worldwide, causing over 200,000 deaths a year. NoV is nonenveloped, with a single-stranded RNA genome, and is primarily transmitted person to person. The viral RNA-dependent RNA polymerase (RdRp) is critical for the production of genomic and subgenomic RNA and is therefore a prime target for antiviral therapies. Using high-throughput screening, nearly 20,000 “lead-like” compounds were tested for inhibitory activity against the NoV genogroup II, genotype 4 (GII.4) RdRp. The four most potent hits demonstrated half-maximal inhibitory concentrations (IC50s) between 5.0 μM and 9.8 μM against the target RdRp. Compounds NIC02 and NIC04 revealed a mixed mode of inhibition, while NIC10 and NIC12 were uncompetitive RdRp inhibitors. When examined using enzymes from related viruses, NIC02 demonstrated broad inhibitory activity while NIC04 was the most specific GII.4 RdRp inhibitor. The antiviral activity was examined using available NoV cell culture models; the GI.1 replicon and the infectious GV.1 murine norovirus (MNV). NIC02 and NIC04 inhibited the replication of the GI.1 replicon, with 50% effective concentrations (EC50s) of 30.1 μM and 71.1 μM, respectively, while NIC10 and NIC12 had no observable effect on the NoV GI.1 replicon. In the MNV model, NIC02 reduced plaque numbers, size, and viral RNA levels in a dose-dependent manner (EC50s between 2.3 μM and 4.8 μM). The remaining three compounds also reduced MNV replication, although with higher EC50s, ranging from 32 μM to 38 μM. In summary, we have identified novel nonnucleoside inhibitor scaffolds that will provide a starting framework for the development and future optimization of targeted antivirals against NoV. PMID:24637690

  8. Norovirus Mechanisms of Immune Antagonism

    PubMed Central

    Roth, Alexa N.; Karst, Stephanie M.

    2015-01-01

    Noroviruses are a leading cause of gastroenteritis outbreaks globally. Several lines of evidence indicate that noroviruses can antagonize or evade host immune responses, including the absence of long-lasting immunity elicited during a primary norovirus exposure and the ability of noroviruses to establish prolonged infections that are associated with protracted viral shedding. Specific norovirus proteins possessing immune antagonist activity have been described in recent years although mechanistic insight in most cases is limited. In this review, we discuss these emerging strategies used by noroviruses to subvert the immune response, including the actions of two nonstructural proteins (p48 and p22) to impair cellular protein trafficking and secretory pathways; the ability of the VF1 protein to inhibit cytokine induction; and the ability of the minor structural protein VP2 to regulate antigen presentation. We also discuss the current state of the understanding of host and viral factors regulating the establishment of persistent norovirus infections along the gastrointestinal tract. A more detailed understanding of immune antagonism by pathogenic viruses will inform prevention and treatment of disease. PMID:26673810

  9. A review of known and hypothetical transmission routes for noroviruses.

    PubMed

    Mathijs, Elisabeth; Stals, Ambroos; Baert, Leen; Botteldoorn, Nadine; Denayer, Sarah; Mauroy, Axel; Scipioni, Alexandra; Daube, Georges; Dierick, Katelijne; Herman, Lieve; Van Coillie, Els; Uyttendaele, Mieke; Thiry, Etienne

    2012-12-01

    Human noroviruses (NoVs) are considered a worldwide leading cause of acute non-bacterial gastroenteritis. Due to a combination of prolonged shedding of high virus levels in feces, virus particle shedding during asymptomatic infections, and a high environmental persistence, NoVs are easily transmitted pathogens. Norovirus (NoV) outbreaks have often been reported and tend to affect a lot of people. NoV is spread via feces and vomit, but this NoV spread can occur through several transmission routes. While person-to-person transmission is without a doubt the dominant transmission route, human infective NoV outbreaks are often initiated by contaminated food or water. Zoonotic transmission of NoV has been investigated, but has thus far not been demonstrated. The presented review aims to give an overview of these NoV transmission routes. Regarding NoV person-to-person transmission, the NoV GII.4 genotype is discussed in the current review as it has been very successful for several decades but reasons for its success have only recently been suggested. Both pre-harvest and post-harvest contamination of food products can lead to NoV food borne illness. Pre-harvest contamination of food products mainly occurs via contact with polluted irrigation water in case of fresh produce or with contaminated harvesting water in case of bivalve molluscan shellfish. On the other hand, an infected food handler is considered as a major cause of post-harvest contamination of food products. Both transmission routes are reviewed by a summary of described NoV food borne outbreaks between 2000 and 2010. A third NoV transmission route occurs via water and the spread of NoV via river water, ground water, and surface water is reviewed. Finally, although zoonotic transmission remains hypothetical, a summary on the bovine and porcine NoV presence observed in animals is given and the presence of human infective NoV in animals is discussed.

  10. Genotype diversity and molecular evolution of noroviruses: A 30-year (1982-2011) comprehensive study with children from Northern Brazil.

    PubMed

    Siqueira, Jones Anderson Monteiro; Bandeira, Renato da Silva; Oliveira, Darleise de Souza; Dos Santos, Liann Filiphe Pereira; Gabbay, Yvone Benchimol

    2017-01-01

    A chronologically comprehensive 30-year study was conducted that involved children living in Belém, in the Amazon region of Northern Brazil, who participated in eight different studies from October 1982 to April 2011. The children were followed either in the community or in health units and hospitals in order to identify the norovirus genotypes involved in infections during this time. A total of 2,520 fecal specimens were obtained and subjected to RT-PCR and nucleotide sequencing for regions A, B, C, D and P2 of the viral genome. An overall positivity of 16.9% (n = 426) was observed, and 49% of the positive samples were genotyped (208/426), evidencing the presence of several genotypes as follows: Polymerase gene (GI.P4, GII.Pa, GII.Pc, GII.Pe, GII.Pg, GII.Pj, GII.P3, GII.P4, GII.P6, GII.P7, GII.P8, GII.P12, GII.P13, GII.P14, GII.P21, GII.P22), and VP1 gene (GI.3, GI.7, GII.1, GII.2, GII.3, GII.4, GII.6, GII.7, GII.8, GII.10, GII.12, GII.14, GII.17, GII.23). The GII.P4/GII.4 genotype determined by both open reading frames (ORFs) (partial polymerase and VP1 genes) was found for 83 samples, and analyses of the subdomain P2 region showed 10 different variants: CHDC (1970s), Tokyo (1980s), Bristol_1993, US_95/96, Kaiso_2003, Asia_2003, Hunter_2004, Yerseke_2006a, Den Haag_2006b (subcluster "O") and New Orleans_2009. Recombination events were confirmed in 47.6% (n = 20) of the 42 samples with divergent genotyping by ORF1 and ORF2 and with probable different breakpoints within the viral genome. The evolutionary analyses estimated a rate of evolution of 1.02 x 10-2 and 9.05 x 10-3 subs./site/year using regions C and D from the VP1 gene, respectively. The present research shows the broad genetic diversity of the norovirus that infected children for 30 years in Belém. These findings contribute to our understanding of noroviruses molecular epidemiology and viral evolution and provide a baseline for vaccine design.

  11. Recent Advances in Understanding Norovirus Pathogenesis

    PubMed Central

    Karst, Stephanie M.; Tibbetts, Scott A.

    2016-01-01

    Noroviruses constitute a family of ubiquitous and highly efficient human pathogens. In spite of decades of dedicated research, human noroviruses remain a major cause of gastroenteritis and severe diarrheal disease around the world. Recent findings have begun to unravel the complex mechanisms that regulate norovirus pathogenesis and persistent infection, including the important interplay between the virus, the host immune system, and commensal bacteria. Herein, we will summarize recent research developments regarding norovirus cell tropism, the use of M cells, and commensal bacteria to facilitate norovirus infection, and virus, host, and bacterial determinants of persistent norovirus infections. PMID:27110852

  12. Molecular epidemiology of norovirus in South Korea.

    PubMed

    Lee, Sung-Geun; Cho, Han-Gil; Paik, Soon-Young

    2015-02-01

    Norovirus is a major cause of viral gastroenteritis and a common cause of foodborne and waterborne outbreaks. Norovirus outbreaks are responsible for economic losses, most notably to the public health and food industry field. Norovirus has characteristics such as low infectious dose, prolonged shedding period, strong stability, great diversity, and frequent genome mutations. Besides these characteristics, they are known for rapid and extensive spread in closed settings such as hospitals, hotels, and schools. Norovirus is well known as a major agent of food-poisoning in diverse settings in South Korea. For these reasons, nationwide surveillance for norovirus is active in both clinical and environmental settings in South Korea. Recent studies have reported the emergence of variants and novel recombinants of norovirus. In this review, we summarized studies on the molecular epidemiology and nationwide surveillance of norovirus in South Korea. This review will provide information for vaccine development and prediction of new emerging variants of norovirus in South Korea.

  13. CDC Vital Signs: Preventing Norovirus Outbreaks

    MedlinePlus

    ... norovirus to others through close contact or by contaminating food and surfaces. Food service workers who have ... evaluation of outbreaks, including the National Outbreak Reporting System, National Voluntary Environmental Assessment Information System, Norovirus Sentinel ...

  14. Norovirus in a United States virgin islands resort: outbreak investigation, response, and costs.

    PubMed

    Leshem, Eyal; Gastañaduy, Paul A; Trivedi, Tarak; Laufer Halpin, Alison; Pringle, Jeshua; Lang, Francine; Gregoricus, Nicole; Vinjé, Jan; Behravesh, Casey Barton; Parashar, Umesh; Hall, Aron J

    2016-05-01

    During 8-20 April 2012, an outbreak of gastrointestinal illness occurred among guests and employees of a resort hotel in St. Thomas, US Virgin Islands. We describe outbreak characteristics, and estimate indirect (non-medical) costs to travellers. Employees who met the case definition were interviewed and provided stool samples. Samples were tested for norovirus by real-time reverse-transcription polymerase chain reaction. Guests were asked to complete a survey aimed to identify and characterize cases, and to estimate quality adjusted vacation days (QAVD) lost. Overall, 66 persons (20 employees and 46 guests) met the probable case definition. The first reported illness onset occurred in a hotel employee on 8 April, while the first reported onset in a guest occurred on 13 April. An employee suffered a public diarrhoea incident on 13 April in the central kitchen, followed by illness onset in the next day among employees that assisted with the clean-up. On 15 April, after 10 guests reported ill, the hotel implemented an outbreak response protocol instructing ill employees to take a 3-day leave, and obtain medical clearance prior to resuming work. Ill guests were advised to self-isolate, and rapid cleaning of public areas and guest rooms where suspected contamination occurred was implemented. We estimated that 65 QAVDs were lost by 43 guests (1.5 days/guest). Using an approximate cost of $450 per vacation day, we estimated indirect illness cost at $675 per guest case. Seven (64%) of 11 cases' stool specimens were positive for norovirus genotype GII.4 Den Haag. A norovirus outbreak in a resort hotel resulted in substantial indirect costs and loss of vacation days to ill travellers. We recommend outbreak control measures including exclusion of ill employees, until ≥48-72 h after resolution of symptoms, self-isolation of ill guests and appropriate cleaning in hotel-associated norovirus outbreaks. Published by Oxford University Press on behalf of the International

  15. Norovirus genotype distribution in outbreaks of acute gastroenteritis among children and older people: an 8-year study.

    PubMed

    Kumazaki, Makoto; Usuku, Shuzo

    2016-11-07

    Noroviruses (NoVs) are the most frequent cause of acute gastroenteritis worldwide among people of all ages and the leading cause of gastrointestinal disease outbreaks in various settings. To clarify the differences in epidemic situations among different settings, we investigated epidemiological trends and the distribution of NoV genotypes in Yokohama, Japan. Between September 2007 and August 2015, 746 outbreaks of NoV gastroenteritis were reported in kindergarten/nursery schools (K/Ns), primary schools (PSs), and nursing homes for the aged (NHs). Stool samples were collected for NoV testing, and the NoV gene was amplified and sequenced to determine the genotype. During the eight seasons, 248 NoV outbreaks occurred in K/Ns, 274 outbreaks in PSs, and 224 outbreaks in NHs. These outbreaks occurred throughout the year, except in August, and the number increased in November and peaked in December. The number of outbreaks that occurred from November to February comprised 76.8 % of all outbreaks. The outbreaks originated in K/Ns or PSs in every season, except for one season. Five genogroup (G)I and nine GII genotypes in K/Ns, six GI and 10 GII genotypes in PSs, and three GI and six GII genotypes in NHs were detected during the eight seasons. GII.4 was the most prevalent genotype in K/Ns and NHs. However, GII.6 was the most prevalent genotype in PSs. The epidemic genotypes in K/Ns and PSs changed by NoV season, although GII.4 was always predominant in NHs. Moreover, the distribution of genotypes was significantly different between epidemic and non-epidemic periods in each facility (p < 0.01 for all). The epidemic situation of NoV outbreaks differs by facility, NoV season, and month. The genotype distribution is likely dependent on the facility and is significantly different between epidemic and non-epidemic periods.

  16. Effects of High-Hydrostatic Pressure on Inactivation of Human Norovirus and Physical and Sensory Characteristics of Oysters.

    PubMed

    Ye, Mu; Lingham, Talaysha; Huang, Yaoxin; Ozbay, Gulnihal; Ji, Lin; Karwe, Mukund; Chen, Haiqiang

    2015-06-01

    The purpose of the study was to determine the effect of high-hydrostatic pressure (HHP) on inactivation of human norovirus (HuNoV) in oysters and to evaluate organoleptic characteristics of oysters treated at pressure levels required for HuNoV inactivation. Genogroup I.1 (GI.1) or Genogroup II.4 (GII.4) HuNoV was inoculated into oysters and treated at 300 to 600 MPa at 25 and 0 °C for 2 min. After HHP, viral particles were extracted by porcine gastric mucin-conjugated magnetic beads (PGM-MBs) and viral RNA was quantified by real-time RT-PCR. Lower initial temperature (0 °C) significantly enhanced HHP inactivation of HuNoV compared to ambient temperature (25 °C; P < 0.05). HHP at 350 and 500 MPa at 0 °C could achieve more than 4 log10 reduction of GII.4 and GI.1 HuNoV in oysters, respectively. HHP treatments did not significantly change color or texture of oyster tissue. A 1- to 5-scale hedonic sensory evaluation on appearance, aroma, color, and overall acceptability showed that pressure-treated oysters received significantly higher quality scores than the untreated control (P < 0.05). Elevated pressure levels at 450 and 500 MPa did not significantly affect scores compared to 300 MPa at 0 °C, indicating increasing pressure level did not affect sensory acceptability of oysters. Oysters treated at 0 °C had slightly lower acceptability than the group treated at room temperature on day 1 (P < 0.05), but after 1 wk storage, no significant difference in sensory attributes and consumer desirability was observed (P > 0.05).

  17. B-Cell Responses to Intramuscular Administration of a Bivalent Virus-like Particle Human Norovirus Vaccine.

    PubMed

    Ramani, Sasirekha; Neill, Frederick H; Ferreira, Jennifer; Treanor, John J; Frey, Sharon E; Topham, David J; Goodwin, Robert R; Borkowski, Astrid; Baehner, Frank; Mendelman, Paul M; Estes, Mary K; Atmar, Robert L

    2017-03-01

    Human noroviruses (HuNoVs) are a leading cause of acute gastroenteritis worldwide. A virus-like particle (VLP) candidate vaccine induces the production of serum histo-blood group antigen (HBGA) blocking antibodies, the first identified correlate of protection from HuNoV gastroenteritis. Recently, virus-specific IgG memory B-cells were identified as another potential correlate of protection against HuNoV gastroenteritis. We assessed B-cell responses following intramuscular administration of a bivalent (GI.1/GII.4) VLP vaccine using protocols identical to those used to evaluate cellular immunity following experimental HuNoV infection. The kinetics and magnitude of cellular immunity to G1.1 infection versus VLP vaccination were compared. Intramuscular immunization with bivalent VLP vaccine induces the production of antibody-secreting cells (ASCs) and memory B-cells. ASC responses peaked at day 7 post 1st dose of vaccine and returned to nearly baseline levels by day 28. Minimal increases in ASCs were seen after a second vaccine dose at day 28. Antigen-specific IgG memory B-cells persist at day 180 post-vaccination for both GI.1 and GII.4 VLPs. The overall trends in B-cell responses to vaccination were similar to infection, where there was a greater bias of ASC response towards IgA and memory B-cell response to IgG. The magnitude of ASC and memory B-cell responses to the GI.1 VLP component of the vaccine were also comparable to responses following GI.1 infection. The production of IgG memory B-cells and persistence at day 180 is a key finding and underscores the need for future studies to determine if IgG memory B-cells are a correlate of protection following vaccination.

  18. Evaluation of high hydrostatic pressure inactivation of human norovirus on strawberries, blueberries, raspberries and in their purees.

    PubMed

    Huang, Runze; Ye, Mu; Li, Xinhui; Ji, Lin; Karwe, Mukund; Chen, Haiqiang

    2016-04-16

    Human norovirus (HuNoV) has been an increasing concern of foodborne illness related to fresh and frozen berries. In this study, high hydrostatic pressure (HHP) inactivation of HuNoV on fresh strawberries, blueberries, and raspberries and in their purees was investigated. Porcine gastric mucin (PGM)-conjugated magnetic beads (PGM-MBs) and real-time reverse transcriptional polymerase chain reaction (RT-qPCR) were utilized for infectious HuNoV discrimination and quantification. Strawberry puree inoculated with HuNoV genogroup I.1 (GI.1) strain was HHP-treated at 450, 500 and 550 MPa for 2 min each at initial sample temperatures of 0, 4 and 20 °C. HuNoV GI.1 strain became more sensitive to HHP treatment as the temperature decreased from 20 to 0 °C. HuNoV GI.1 or genogroup II.4 (GII.4) strains were inoculated into three types of berries and their purees and treated at pressure levels from 250 to 650 MPa for 2 min at initial sample temperature of 0 °C. For the purees, the HHP condition needed to achieve >2.9 log reduction of HuNoV GI.1 strain and >4.0 log reduction of HuNoV GII.4 strain was found to be ≥ 550 MPa for 2 min at 0 °C. HHP treatment showed better inactivation effect of HuNoV on blueberries than on strawberry quarters and raspberries. HuNoV GI.1 strain was more resistant to HHP treatment than HuNoV GII.4 strain under different temperatures and environment. The physical properties and sensory qualities of HHP-treated and untreated blueberries and the three types of berry purees were evaluated. Color, pH and viscosity of blueberries and three berry purees showed no or slight changes after HHP treatment. Sensory evaluation demonstrated that HHP treatment of 550 MPa for 2 min at 0 °C did not significantly reduced the sensory qualities of three berry purees. The results demonstrated that the HHP treatment of 550 MPa for 2 min at 0 °C could be a potential nonthermal intervention for HuNoV in berry purees without adversely affecting their sensory qualities

  19. Novel norovirus in dogs with diarrhea.

    PubMed

    Mesquita, João Rodrigo; Barclay, Leslie; Nascimento, Maria São José; Vinjé, Jan

    2010-06-01

    To identify the prevalence and genetic variability of noroviruses in dogs, we tested fecal samples by using reverse transcription-PCR. We found canine norovirus in 40% and 9% of dogs with and without diarrhea, respectively. The virus was genetically unrelated to other noroviruses and constitutes a tentative new genogroup.

  20. Attachment and localization of human norovirus and animal caliciviruses in fresh produce.

    PubMed

    DiCaprio, Erin; Purgianto, Anastasia; Ma, Yuanmei; Hughes, John; Dai, Xiangjun; Li, Jianrong

    2015-10-15

    Fresh produce is a high risk food for human norovirus (NoV) contamination. To help control this pathogen in fresh produce, a better understanding of the interaction of human NoV and fresh produce needs to be established. In this study the attachment of human NoV and animal caliciviruses (murine norovirus, MNV-1; Tulane virus, TV) to fresh produce was evaluated, using both visualization and viral enumeration techniques. It was found that a human NoV GII.4 strain attached efficiently to the Romaine lettuce leaves and roots and green onion shoots, and that washing with PBS or 200 ppm of chlorine removed less than 0.4 log of viral RNA copies from the tissues. In contrast, TV and MNV-1 bound more efficiently to Romaine lettuce leaves than to the roots, and simple washing removed less than 1 log of viruses from the lettuce leaves and 1-4 log PFU of viruses from roots. Subsequently, the location of virus particles in fresh produce was visualized using a fluorescence-based Quantum Dots (Q-Dots) assay and confocal microscopy. It was found that human NoV virus-like particles (VLPs), TV, and MNV-1 associated with the surface of Romaine lettuce and were found aggregating in and around the stomata. In green onions, human NoV VLPs were found between the cells of the epidermis and cell walls of both the shoots and roots. However, TV and MNV-1 were found to be covering the surface of the epidermal cells in both the shoots and roots of green onions. Collectively, these results demonstrate that (i) washing with 200 ppm chlorine is ineffective in removing human NoV from fresh produce; and (ii) different viruses vary in their localization patterns to different varieties of fresh produce.

  1. Internalization and Dissemination of Human Norovirus and Animal Caliciviruses in Hydroponically Grown Romaine Lettuce

    PubMed Central

    DiCaprio, Erin; Ma, Yuanmei; Purgianto, Anastasia; Hughes, John

    2012-01-01

    Fresh produce is a major vehicle for the transmission of human norovirus (NoV) because it is easily contaminated during both pre- and postharvest stages. However, the ecology of human NoV in fresh produce is poorly understood. In this study, we determined whether human NoV and its surrogates can be internalized via roots and disseminated to edible portions of the plant. The roots of romaine lettuce growing in hydroponic feed water were inoculated with 1 × 106 RNA copies/ml of a human NoV genogroup II genotype 4 (GII.4) strain or 1 × 106 to 2 × 106 PFU/ml of animal caliciviruses (Tulane virus [TV] and murine norovirus [MNV-1]), and plants were allowed to grow for 2 weeks. Leaves, shoots, and roots were homogenized, and viral titers and/or RNA copies were determined by plaque assay and/or real-time reverse transcription (RT)-PCR. For human NoV, high levels of viral-genome RNA (105 to 106 RNA copies/g) were detected in leaves, shoots, and roots at day 1 postinoculation and remained stable over the 14-day study period. For MNV-1 and TV, relatively low levels of infectious virus particles (101 to 103 PFU/g) were detected in leaves and shoots at days 1 and 2 postinoculation, but virus reached a peak titer (105 to 106 PFU/g) at day 3 or 7 postinoculation. In addition, human NoV had a rate of internalization comparable with that of TV as determined by real-time RT-PCR, whereas TV was more efficiently internalized than MNV-1 as determined by plaque assay. Taken together, these results demonstrated that human NoV and animal caliciviruses became internalized via roots and efficiently disseminated to the shoots and leaves of the lettuce. PMID:22729543

  2. Wipes Coated with a Singlet-Oxygen-Producing Photosensitizer Are Effective against Human Influenza Virus but Not against Norovirus

    PubMed Central

    Bouwknegt, Martijn; Rutjes, Saskia; de Roda Husman, Ana Maria

    2014-01-01

    Transmission of enteric and respiratory viruses, including human norovirus (hNoV) and human influenza virus, may involve surfaces. In food preparation and health care settings, surfaces are cleaned with wipes; however, wiping may not efficiently reduce contamination or may even spread viruses, increasing a potential public health risk. The virucidal properties of wipes with a singlet-oxygen-generating immobilized photosensitizer (IPS) coating were compared to those of similar but uncoated wipes (non-IPS) and of commonly used viscose wipes. Wipes were spiked with hNoV GI.4 and GII.4, murine norovirus 1 (MNV-1), human adenovirus type 5 (hAdV-5), and influenza virus H1N1 to study viral persistence. We also determined residual and transferred virus proportions on steel carriers after successively wiping a contaminated and an uncontaminated steel carrier. On IPS wipes only, influenza viruses were promptly inactivated with a 5-log10 reduction. D values of infectious MNV-1 and hAdV-5 were 8.7 and 7.0 h on IPS wipes, 11.6 and 9.3 h on non-IPS wipes, and 10.2 and 8.2 h on viscose wipes, respectively. Independently of the type of wipe, dry cleaning removed, or drastically reduced, initial spot contamination of hNoV on surfaces. All wipes transferred hNoV to an uncontaminated carrier; however, the risk of continued transmission by reuse of wipes after 6 and 24 h was limited for all viruses. We conclude that cleaning wet spots with dry wipes efficiently reduced spot contamination on surfaces but that cross-contamination with noroviruses by wiping may result in an increased public health risk at high initial virus loads. For influenza virus, IPS wipes present an efficient one-step procedure for cleaning and disinfecting contaminated surfaces. PMID:24814795

  3. Zeta Potential and Aggregation of Virus-Like Particle of Human Norovirus and Feline Calicivirus Under Different Physicochemical Conditions.

    PubMed

    Samandoulgou, Idrissa; Fliss, Ismaïl; Jean, Julie

    2015-09-01

    Although the spread of human norovirus reportedly depends on its ability to bind to food materials, the mechanism of the phenomenon remains unknown. Since protein size and electrical charge are reportedly important parameters in their adsorption, the current work is focused on determining human noroviruses isoelectric point (IEP), electrical charge and aggregate size at different pH, ionic strength (IS), and temperature. Using the baculovirus expression vector system, we produced and purified virus-like particles (VLPs) of GI.1 and GII.4 noroviruses and feline calicivirus, determined their IEP, and examined their size and electrical charge using a Zetasizer Nano ZS apparatus. Shape and size were also visualized using transmission electron microscopy. IEPs were found close to pH 4. Net charge increased as the pH deviated from the IEP. VLPs were negatively charged at all IS tested and showed a gradual decrease in charge with increasing IS. At low temperature, VLPs were 20-45 nm in diameter at pH far from their IEP and under almost all IS conditions, while aggregates appeared at or near the IEP. At increased temperatures, aggregates appeared at or near the IEP and at high IS. Aggregation at the IEP was also confirmed by microscopy. This suggests that electrostatic interactions would be the predominant factor in VLPs adhesion at pH far from 4 and at low ionic strength. In contrast, non-electrostatic interactions would prevail at around pH 4 and would be reinforced by aggregates, since size generally favors multiple bonding with sorbents.

  4. Antiviral effects of persimmon extract on human norovirus and its surrogate, bacteriophage MS2.

    PubMed

    Kamimoto, Maki; Nakai, Yoshiaki; Tsuji, Toru; Shimamoto, Toshi; Shimamoto, Tadashi

    2014-05-01

    Human noroviruses (NoVs) are the leading cause of gastroenteritis and foodborne illnesses worldwide. In this study, we investigated the effects of persimmon extract (PE) on NoV GII.4 and bacteriophage MS2. We also examined the relationship between the tannin content of PE and its antiviral effects to identify the active ingredient in PE. Different persimmon tannin (PT) solutions were prepared by mixing PE with different concentrations of bovine serum albumin. The antiviral efficacy of these solutions against NoV was evaluated by quantifying the amount of residual noroviral genome using a quantitative reverse transcription PCR (qRT-PCR) assay. The antiviral efficacy of PE against MS2 was examined with an infectivity assay (plaque assay). Solutions containing ≥ 0.11 mg/mL PT reduced the noroviral genome by more than 70.0% and the infectivity of MS2 by more than 2.5 log PFU/mL. However, the effects of PT on both viruses decreased markedly at a concentration of 0.08 mg/mL and solutions containing negligible PT had no antiviral activity. These results suggest that the PT component of PE inactivates NoV and MS2. Our results indicate that PE is a nontoxic antiviral agent effective against enteric viruses. Persimmon extract showed antiviral effects against NoV and bacteriophage MS2. Persimmon extract is suitable for use as an antiviral agent. © 2014 Institute of Food Technologists®

  5. Environmental indicators for human norovirus outbreaks.

    PubMed

    Shamkhali Chenar, Shima; Deng, Zhiqiang

    2017-02-01

    Norovirus is the most common cause of outbreaks of non-bacterial gastroenteritis in human. While the winter seasonality of norovirus outbreaks has been widely reported, the association between norovirus outbreak epidemics and environmental factors remains not fully understood. This literature review is intended to improve understanding of environmental factors governing norovirus outbreaks and how the factors affect norovirus transmission. To that end, a large number of studies (67) from countries around the world were critically reviewed and discussed. Results of the literature review show that temperature, humidity, and rainfall are the most important environmental variables governing the norovirus epidemic cycle. It was found that low temperature between -6.6 and 20 °C, relative humidity between 10 and 66 %, and rainfall from 1 day to 3 months before an outbreak are effective ranges of the environmental factors, which favor the prevalence of norovirus. Some other environmental factors might have an association with the cycle of norovirus epidemics. However, further investigations are needed to understand effects of the other factors on norovirus incidence. The findings of this literature review improve our understanding of the relationship between norovirus outbreaks and environmental factors and provide the direction for future research on norovirus outbreaks.

  6. [Chronic norovirus infection in an immunocompromised patient].

    PubMed

    Lambregts, Merel M C; Alleman, Maarten A; Ruys, Gijs J H M; Groeneveld, Paul H P

    2010-01-01

    A 68-year-old man, immunocompromised due to non-Hodgkin lymphoma and chemotherapy, was admitted for a community-acquired norovirus infection. He developed chronic intermittent diarrhoea and cachexia. A video-capsule examination showed severe mucosal atrophy in the jejunum. The patient died eight months after the initial norovirus infection. Eight of the nine stool examinations were positive for the norovirus during this entire period. Excretion of norovirus is known to persist after the symptoms have been resolved. However, there is only one previously reported case of excretion over such a long period. Recognising a chronic norovirus infection in immunocompromised patients is vital as then complications such as mucosal atrophy with malabsorption and cachexia can be diagnosed and supportive therapy can be started. Furthermore, recognising a chronic norovirus infection is essential for preventing norovirus outbreaks. Infected patients should always be isolated, regardless of their symptoms and faecal viral load.

  7. Norovirus Surveillance: An Epidemiological Perspective.

    PubMed

    Harris, John P

    2016-02-01

    Surveillance for norovirus is challenging because the nature of illness due to norovirus is such that the majority of people who are infected will not have any contact with medical services and are highly unlikely to have a sample collected for diagnosis. Public health advice urges people to not visit hospitals or their family physicians, to prevent the risk further spread. The recognition of the importance of this pathogen was quickly established following the introduction of surveillance of outbreaks of gastrointestinal infection in England and Wales in 1992. This period saw >1800 outbreaks of norovirus infection reported in hospitals in England, affecting >45 000 patients and staff. A new system for reporting outbreaks of norovirus infection in hospitals, the Hospital Norovirus outbreak Reporting Scheme (HNORS), began in January 2009. Summary information on outbreaks is provided by infection control staff at hospitals and includes questions on the date the first and last person in the outbreak became symptomatic and whether closure of a bay or ward was needed. In the first 3 years (2009-2011) of the HNORS surveillance scheme, 4000 outbreaks were reported, affecting 40 000 patients and 10 000 staff. Over the last 3 years, these outbreaks have been associated with an average of 13 000 patients and 3400 staff becoming ill, with 15 000 lost bed-days annually. With the possible introduction of a vaccine on the horizon, targeted research with a more integrated approach to laboratory testing and outbreak reporting is essential to a greater understanding of the epidemiology of norovirus. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  8. Norovirus Transmission on Cruise Ship

    PubMed Central

    Isakbaeva, Elmira T.; Beard, R. Suzanne; Bulens, Sandra N.; Mullins, James; Monroe, Stephan S.; Bresee, Joseph; Sassano, Patricia; Cramer, Elaine H.; Glass, Roger I.

    2005-01-01

    We describe an investigation of a norovirus gastroenteritis outbreak aboard a cruise ship affecting 6 consecutive cruises and the use of sequence analysis to determine modes of virus transmission. Noroviruses (NoV), are the most common cause of infectious acute gastroenteritis and are transmitted feco-orally through food and water, directly from person to person and by environmental contamination (1). These viruses are often responsible for protracted outbreaks in closed settings, such as cruise ships, nursing homes, and hospitals (2,3). PMID:15705344

  9. Molecular Characterization of Noroviruses and HBGA from Infected Quilombola Children in Espirito Santo State, Brazil

    PubMed Central

    Vicentini, Fernando; Denadai, Wilson; Gomes, Yohanna Mayelle; Rose, Tatiana L.; Ferreira, Mônica S. R.; Le Moullac-Vaidye, Beatrice; Le Pendu, Jacques; Leite, José Paulo Gagliardi; Miagostovich, Marize Pereira; Spano, Liliana Cruz

    2013-01-01

    Noroviruses (NoV) are the main etiological agents of gastroenteritis outbreaks worldwide and susceptibility to NoV infection has been related to the histo-blood group antigen (HBGA). This study aimed to determine the prevalence of NoV strains and to evaluate the HBGA phenotype and genotype of children from semi-isolated Quilombola communities, descendents of black slaves in Brazil. A total of 397 children up to eleven years old, with and without diarrhea, from Quilombola Communities in the Espirito Santo State, Brazil, were investigated for the presence of NoV from August 2007 to September 2009. Feces were collected from all the children, and blood from the NoV positive children. NoV was screened by reverse transcription-PCR with primers for the RNA-dependent RNA polymerase region; genogroup was determined by PCR with primers for the C and D regions and genotyped by sequencing. HBGA phenotype was performed by gel-spinning and FUT2 and FUT3 were analyzed by PCR or sequencing analysis. NoV were detected in 9.2% (12/131) of diarrheic and 1.5% (4/266) of non-diarrheic children (p<0.05, Fisher’s exact test). GI and GII genogroups were present in 12.5% and 87.5% of the samples, respectively. The following genotypes were characterized: GII.4 (25%), GII.12 (25%), GII.6 (12.5%) and GI.1 (6.3%), GI.3 (12.5%) and GI.4 (6.3%). Children infected with NoV showed the A (n = 6), O (n = 6), and B (n = 2) HBGA phenotypes, and 13 of them were classified as secretors (Se) and one as a non secretor (se). Mutations of Se40, 171,216,357,428,739,960 were found for the FUT2 gene and mutations of Le59, 202, 314 for the FUT3 gene. The only se child was infected by NoV GI, whereas the Se children were indiscriminately infected by GI or GII. This study showed rates of NoV infection in symptomatic and asymptomatic Quilombola children consistent with other studies. However, children under 12 months were seven times more affected than those between 1 and 5 years old. GII.12 was as

  10. High prevalence of norovirus in children with sporadic acute gastroenteritis in Manaus, Amazon Region, northern Brazil.

    PubMed

    Costa, Samya Thalita Picanço da; Fumian, Tulio Machado; Lima, Ian Carlos Gomes de; Siqueira, Jones Anderson Monteiro; Silva, Luciana Damascena da; Hernández, Juliana das Mercês; Lucena, Maria Silvia Souza de; Reymão, Tammy Kathlyn Amaral; Soares, Luana da Silva; Mascarenhas, Joana D'Arc Pereira; Gabbay, Yvone Benchimol

    2017-06-01

    Norovirus (NoV) is a major cause of acute gastroenteritis (AGE) worldwide, especially in children under five years. Studies involving the detection and molecular characterisation of NoV have been performed in Brazil, demonstrating its importance as an etiological agent of AGE. The objectives of this study were to investigate the frequency of human NoV and to genotype the strains isolated from 0-14-year-old patients of AGE in Manaus, Brazil, over a period of two years. A total of 426 faecal samples were collected between January 2010 and December 2011. All samples were tested for the presence of NoV antigens using a commercial enzyme immunoassay kit. RNA was extracted from all faecal suspensions and reverse transcription-polymerase chain reaction (RT-PCR) for the NoV-polymerase partial region was performed as a trial test. Positive samples were then subjected to PCR with specific primers for partial capsid genes, which were then sequenced. NoV was detected in 150 (35.2%) faecal samples, for at least one of the two techniques used. NoV was detected in children from all age groups, with the highest positivity observed among the group of 1-2 years old. Clinically, fever was verified in 43% of the positive cases and 46.3% of the negative cases, and vomiting was observed in 75.8% and 70.8% cases in these groups, respectively. Monthly distribution showed that the highest positivity was observed in January 2010 (81.2%), followed by February and April 2010 and March 2011, when the positivity rate reached almost 50%. Phylogenetic analyses performed with 65 positive strains demonstrated that 58 (89.2%) cases of NoV belonged to genotype GII.4, five (7.7%) to GII.6, and one (1.5%) each to GII.7 and GII.3. This research revealed a high circulation of NoV GII.4 in Manaus and contributed to the understanding of the importance of this virus in the aetiology of AGE cases, especially in a region with such few studies available.

  11. Computational studies on the interaction of ABO-active saccharides with the norovirus VA387 capsid protein can explain experimental binding data

    NASA Astrophysics Data System (ADS)

    Koppisetty, Chaitanya A. K.; Nasir, Waqas; Strino, Francesco; Rydell, Gustaf E.; Larson, Göran; Nyholm, Per-Georg

    2010-05-01

    Norovirus strains are known to cause recurring epidemics of winter vomiting disease. The crystal structure of the capsid protein of VA387, a representative of the clinically important GII.4 genocluster, was recently solved in complex with histo-blood group A- and B-trisaccharides. However, the VA387 strain is known to bind also to other natural carbohydrates for which detailed structural information of the complexes is not available. In this study we have computationally explored the fit of the VA387 with a set of naturally occurring carbohydrate ligands containing a terminal α1,2-linked fucose. MD simulations both with explicit and implicit solvent models indicate that type 1 and 3 extensions of the ABO-determinant including ALeb and BLeb pentasaccharides can be well accommodated in the site. Scoring with Glide XP indicates that the downstream extensions of the ABO-determinants give an increase in binding strength, although the α1,2-linked fucose is the single strongest interacting residue. An error was discovered in the geometry of the GalNAc-Gal moiety of the published crystal structure of the A-trisaccharide/VA387 complex. The present modeling of the complexes with histo-blood group A-active structures shows some contacts which provide insight into mutational data, explaining the involvement of I389 and Q331. Our results can be applicable in structure-based design of adhesion inhibitors of noroviruses.

  12. Norovirus transmission on cruise ship.

    PubMed

    Isakbaeva, Elmira T; Widdowson, Marc-Alain; Beard, R Suzanne; Bulens, Sandra N; Mullins, James; Monroe, Stephan S; Bresee, Joseph; Sassano, Patricia; Cramer, Elaine H; Glass, Roger I

    2005-01-01

    An outbreak of norovirus gastroenteritis affected passengers on two consecutive cruises of ship X and continued on 4 subsequent cruises despite a 1-week sanitization. We documented transmission by food and person-to-person contact; persistence of virus despite sanitization onboard, including introductions of new strains; and seeding of an outbreak on land.

  13. Engineering Bacterial Surface Displayed Human Norovirus Capsid Proteins: A Novel System to Explore Interaction Between Norovirus and Ligands

    PubMed Central

    Niu, Mengya; Yu, Qianqian; Tian, Peng; Gao, Zhiyong; Wang, Dapeng; Shi, Xianming

    2015-01-01

    Human noroviruses (HuNoVs) are major contributors to acute nonbacterial gastroenteritis outbreaks. Many aspects of HuNoVs are poorly understood due to both the current inability to culture HuNoVs, and the lack of efficient small animal models. Surrogates for HuNoVs, such as recombinant viral like particles (VLPs) expressed in eukaryotic system or P particles expressed in prokaryotic system, have been used for studies in immunology and interaction between the virus and its receptors. However, it is difficult to use VLPs or P particles to collect or isolate potential ligands binding to these recombinant capsid proteins. In this study, a new strategy was used to collect HuNoVs binding ligands through the use of ice nucleation protein (INP) to display recombinant capsid proteins of HuNoVs on bacterial surfaces. The viral protein-ligand complex could be easily separated by a low speed centrifugation step. This system was also used to explore interaction between recombinant capsid proteins of HuNoVs and their receptors. In this system, the VP1 capsid encoding gene (ORF2) and the protruding domain (P domain) encoding gene (3′ terminal fragment of ORF2) of HuNoVs GI.1 and GII.4 were fused with 5′ terminal fragment of INP encoding gene (inaQn). The results demonstrated that the recombinant VP1 and P domains of HuNoVs were expressed and anchored on the surface of Escherichia coli BL21 cells after the bacteria were transformed with the corresponding plasmids. Both cell surface displayed VP1 and P domains could be recognized by HuNoVs specific antibodies and interact with the viral histo-blood group antigens receptors. In both cases, displayed P domains had better binding abilities than VP1. This new strategy of using displayed HuNoVs capsid proteins on the bacterial surface could be utilized to separate HuNoVs binding components from complex samples, to investigate interaction between the virus and its receptors, as well as to develop an oral vaccine for HuNoVs. PMID

  14. Etiological study of enteric viruses and the genetic diversity of norovirus, sapovirus, adenovirus, and astrovirus in children with diarrhea in Chongqing, China.

    PubMed

    Ren, Zengzhi; Kong, Yuanmei; Wang, Jun; Wang, Qianqian; Huang, Ailong; Xu, Hongmei

    2013-09-03

    Enteric viruses are a major cause of diarrhea in children, especially those <5 years old. Identifying the viral agents is critical to the development of effective preventive measures. This study aimed to determine the prevalence of common enteric viruses in children <5 years old presented with diarrhea to the Children's Hospital of Chongqing Medical University. Five hundred fecal samples were collected between August and November 2010 from children <5 years of age who presented with acute diarrhea at the Children's Hospital of Chongqing Medical University. All samples were tested for rotaviruses A, B, and C, noroviruses GI and GII, adenovirus, sapovirus, and astrovirus using enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction (RT-PCR), or PCR. Partial sequences of norovirus, sapovirus, adenovirus, and astrovirus were phylogenetically analyzed to determine the genotype. Enteric viruses were detected in 302 of the 500 children who presented with acute diarrhea (277/477; 58.07%) and persistent diarrhea (5/23; 21.74%). In 277 samples from children with acute diarrhea in whom at least one viral agent was found, rotavirus A was the most frequent virus identified (132 cases; 27.67%), followed by norovirus GII in 130 cases (27.25%), adenovirus in 30 cases (6.29%), sapovirus in 9 cases (1.89%) and astrovirus in one case (0.21%). Twenty-two of the norovirus GII-positive cases were randomly selected for genotyping. GII/4 was the predominant strain, followed by GII/6, GII/2, GII/3, and GII/7. Sapovirus was classified into four genotypes: GI/1 was predominant, followed by GI/2, GII/1, and GIV. The predominant adenovirus was type 41. Mixed infections were found in 25 cases, all of which presented with acute diarrhea (25/477; 5.24%). Viruses were positive in 5/23 (21.74%) cases with persistent diarrhea. Neither rotavirus B, rotavirus C, nor norovirus GI were found in any of the samples. Enteric viruses are a major cause of diarrhea in children <5

  15. Detection of Norovirus GII.17 Kawasaki 2014 in Shellfish, Marine Water and Underwater Sewage Discharges in Italy.

    PubMed

    La Rosa, G; Della Libera, S; Iaconelli, M; Proroga, Y T R; De Medici, D; Martella, V; Suffredini, E

    2017-03-03

    Norovirus (NoV) is a major cause of non-bacterial acute gastroenteritis worldwide, and the variants of genotype GII.4 are currently the predominant human strains. Recently, a novel variant of NoV GII.17 (GII.P17_GII.17 NoV), termed Kawasaki 2014, has been reported as the cause of gastroenteritis outbreaks in Asia, replacing the pandemic strain GII.4 Sydney 2012. The GII.17 Kawasaki 2014 variant has also been reported sporadically in patients with gastroenteritis outside of Asia, including Italy. In this study, 384 shellfish samples were subjected to screening for human NoVs using real-time PCR and 259 (67.4%) tested positive for Genogroup II (GII) NoV. Of these, 52 samples, selected as representative of different areas and sampling dates, were further amplified by conventional PCR targeting the capsid gene, using broad-range primers. Forty shellfish samples were characterized by amplicon sequencing as GII.4 (n = 29), GII.2 (n = 4), GII.6 (n = 2), GII.12 (n = 2), and GII.17 (n = 3). Sixty-eight water samples (39 seawater samples from the corresponding shellfish production areas and 29 water samples from nearby underwater sewage discharge points) were also tested using the above broad-range assay: eight NoV-positive samples were characterized as GII.1 (n = 3), GII.2 (n = 1), GII.4 (n = 2), and GII.6 (n = 2). Based on full genome sequences available in public databases, a novel RT-PCR nested assay specific for GII.17 NoVs was designed and used to re-test the characterized shellfish (40) and water (8) samples. In this second screening, the RNA of GII.17 NoV was identified in 17 additional shellfish samples and in one water sample. Upon phylogenetic analysis, these GII.17 NoV isolates were closely related to the novel GII.17 Kawasaki 2014. Interestingly, our findings chronologically matched the emergence of the Kawasaki 2014 variant in the Italian population (early 2015), as reported by hospital-based NoV surveillance. These results, showing GII.17 No

  16. Pathogenesis of noroviruses, emerging RNA viruses.

    PubMed

    Karst, Stephanie M

    2010-03-01

    Human noroviruses in the family Caliciviridae are a major cause of epidemic gastroenteritis. They are responsible for at least 95% of viral outbreaks and over 50% of all outbreaks worldwide. Transmission of these highly infectious plus-stranded RNA viruses occurs primarily through contaminated food or water, but also through person-to-person contact and exposure to fomites. Norovirus infections are typically acute and self-limited. However, disease can be much more severe and prolonged in infants, elderly, and immunocompromised individuals. Norovirus outbreaks frequently occur in semi-closed communities such as nursing homes, military settings, schools, hospitals, cruise ships, and disaster relief situations. Noroviruses are classified as Category B biodefense agents because they are highly contagious, extremely stable in the environment, resistant to common disinfectants, and associated with debilitating illness. The number of reported norovirus outbreaks has risen sharply since 2002 suggesting the emergence of more infectious strains. There has also been increased recognition that noroviruses are important causes of childhood hospitalization. Moreover, noroviruses have recently been associated with multiple clinical outcomes other than gastroenteritis. It is unclear whether these new observations are due to improved norovirus diagnostics or to the emergence of more virulent norovirus strains. Regardless, it is clear that human noroviruses cause considerable morbidity worldwide, have significant economic impact, and are clinically important emerging pathogens. Despite the impact of human norovirus-induced disease and the potential for emergence of highly virulent strains, the pathogenic features of infection are not well understood due to the lack of a cell culture system and previous lack of animal models. This review summarizes the current understanding of norovirus pathogenesis from the histological to the molecular level, including contributions from new model

  17. Development of a Gaussia Luciferase-Based Human Norovirus Protease Reporter System: Cell Type-Specific Profile of Norwalk Virus Protease Precursors and Evaluation of Inhibitors

    PubMed Central

    Qu, Lin; Vongpunsawad, Sompong; Atmar, Robert L.; Prasad, B. V. Venkataram

    2014-01-01

    ABSTRACT Norwalk virus (NV) is the prototype strain of human noroviruses (HuNoVs), a group of positive-strand RNA viruses in the Caliciviridae family and the leading cause of epidemic gastroenteritis worldwide. Investigation of HuNoV replication and development of antiviral therapeutics in cell culture remain challenging tasks. Here, we present NoroGLuc, a HuNoV protease reporter system based on a fusion of NV p41 protein with a naturally secreted Gaussia luciferase (GLuc), linked by the p41/p22 cleavage site for NV protease (Pro). trans cleavage of NoroGLuc by NV Pro or Pro precursors results in release and secretion of an active GLuc. Using this system, we observed a cell type-specific activity profile of NV Pro and Pro precursors, suggesting that the activity of NV Pro is modulated by other viral proteins in the precursor forms and strongly influenced by cellular factors. NoroGLuc was also cleaved by Pro and Pro precursors generated from replication of NV stool RNA in transfected cells, resulting in a measurable increase of secreted GLuc. Truncation analysis revealed that the N-terminal membrane association domain of NV p41 is critical for NoroGLuc activity. Although designed for NV, a genogroup GI.1 norovirus, NoroGLuc also efficiently detects Pro activities from GII.3 and GII.4 noroviruses. At noncytotoxic concentrations, protease inhibitors ZnCl2 and Nα-p-tosyl-l-lysine chloromethyl ketone (TLCK) exhibited dose-dependent inhibitory effects on a GII.4 Pro by NoroGLuc assay. These results establish NoroGLuc as a pan-genogroup HuNoV protease reporter system that can be used for the study of HuNoV proteases and precursors, monitoring of viral RNA replication, and evaluation of antiviral agents. IMPORTANCE Human noroviruses are the leading cause of epidemic gastroenteritis worldwide. Currently, there are no vaccines or antiviral drugs available to counter these highly contagious viruses. These viruses are currently noncultivatable in cell culture. Here, we report

  18. Norovirus Genotypes Present in Oysters and in Effluent from a Wastewater Treatment Plant during the Seasonal Peak of Infections in Ireland in 2010

    PubMed Central

    Waters, Allison; Keaveney, Sinéad; Flannery, John; Tuite, Gráinne; Coughlan, Suzie; O'Flaherty, Vincent; Doré, William

    2013-01-01

    We determined norovirus (NoV) concentrations in effluent from a wastewater treatment plant and in oysters during the peak period of laboratory-confirmed cases of NoV infection in Ireland in 2010 (January to March). Weekly samples of influent, secondary treated effluent, and oysters were analyzed using real-time quantitative reverse transcription-PCR for NoV genogroup I (GI) and genogroup II (GII). The mean concentration of NoV GII (5.87 × 104 genome copies 100 ml−1) in influent wastewater was significantly higher than the mean concentration of NoV GI (1.40 × 104 genome copies 100 ml−1). The highest concentration of NoV GII (2.20 × 105 genome copies 100 ml−1) was detected in influent wastewater during week 6. Over the study period, a total of 931 laboratory-confirmed cases of NoV GII infection were recorded, with the peak (n = 171) occurring in week 7. In comparison, 16 cases of NoV GI-associated illness were reported during the study period. In addition, the NoV capsid N/S domain was molecularly characterized for selected samples. Multiple genotypes of NoV GI (GI.1, GI.4, GI.5, GI.6, and GI.7) and GII (GII.3, GII.4, GII.6, GII.7, GII.12, GII.13, and GII.17), as well as 4 putative recombinant strains, were detected in the environmental samples. The NoV GII.4 variant 2010 was detected in wastewater and oyster samples and was the dominant strain detected in NoV outbreaks at that time. This study demonstrates the diversity of NoV genotypes present in wastewater during a period of high rates of NoV infection in the community and highlights the potential for the environmental spread of multiple NoV genotypes. PMID:23396337

  19. Molecular characterization and multiple infections of rotavirus, norovirus, sapovirus, astrovirus and adenovirus in outpatients with sporadic gastroenteritis in Shanghai, China, 2010-2011.

    PubMed

    Lu, Lijuan; Jia, Ran; Zhong, Huaqing; Xu, Menghua; Su, Liyun; Cao, Lingfeng; Dong, Zuoquan; Dong, Niuniu; Xu, Jin

    2015-05-01

    Rotavirus (RV), norovirus (NoV), sapovirus (SaV), human astrovirus (HAstV) and human adenovirus (HAdV) are significant because they are the most common pathogens that cause diarrhea in young children. The aim of this study was to investigate the genetic characteristics and compare the roles of these five viruses in outpatient children with diarrhea in Shanghai. A total of 436 fecal samples were collected from pediatric patients with acute gastroenteritis from January 2010 to December 2011. The selected samples were subjected to reverse transcription PCR (RT-PCR) or PCR to detect and genotype RV, NoV, SaV, HAstV and HAdV. RV (43.3 %, 189/436) was the most prevalent virus, followed by NoV (28.9 %, 126/436), HAdV (7.1 %, 31/436). HAstV (1.8 %, 8/436) and SaV (0.5 %, 2/436). The percentage of multiple infection cases was 14.9 % (65/436), and RV + NoV was the predominant mixed infection. The RV genotype combinations of P[8]G3 (52/189, 27.5 %), P[8]G1 (51/189, 26.9 %) and P[8]G9 (48/189, 25.4 %) occurred most frequently. The predominant NoV genotype was GII.4 (73.0 %, 92/126), and the majority of GII.4 clustered as GII.4-2006b (65.2 %, 60/92). Two of the SaV cases were identified as GI.2 and GII.1. All HAstV-positive samples belonged to HAstV-1. The predominant HAdV type was HAdV-41 (45.2 %, 14/31). This study clearly shows the diversity of the viral causative agents of acute gastroenteritis in outpatient children in Shanghai, which will provide baseline information for future vaccination strategies and development in this area.

  20. Histo-Blood Group Antigen Presentation Is Critical for Binding of Norovirus VLP to Glycosphingolipids in Model Membranes.

    PubMed

    Nasir, Waqas; Frank, Martin; Kunze, Angelika; Bally, Marta; Parra, Francisco; Nyholm, Per-Georg; Höök, Fredrik; Larson, Göran

    2017-03-27

    Virus entry depends on biomolecular recognition at the surface of cell membranes. In the case of glycolipid receptors, these events are expected to be influenced by how the glycan epitope close to the membrane is presented to the virus. This presentation of membrane-associated glycans is more restricted than that of glycans in solution, particularly because of orientational constraints imposed on the glycolipid through its lateral interactions with other membrane lipids and proteins. We have developed and employed a total internal reflection fluorescence microscopy-based binding assay and a scheme for molecular dynamics (MD) membrane simulations to investigate the consequences of various glycan presentation effects. The system studied was histo-blood group antigen (HBGA) epitopes of membrane-bound glycosphingolipids (GSLs) derived from small intestinal epithelium of humans (type 1 chain) and dogs (type 2 chain) interacting with GII.4 norovirus-like particles. Our experimental results showed strong binding to all lipid-linked type 1 chain HBGAs but no or only weak binding to the corresponding type 2 chain HBGAs. This is in contrast to results derived from STD experiments with free HBGAs in solution where binding was observed for Lewis x. The MD data suggest that the strong binding to type 1 chain glycolipids was due to the well-exposed (1,2)-linked α-l-Fucp and (1,4)-linked α-l-Fucp residues, while the weaker binding or lack of binding to type 2 chain HBGAs was due to the very restricted accessibility of the (1,3)-linked α-l-Fucp residue when the glycolipid is embedded in a phospholipid membrane. Our results not only contribute to a general understanding of protein-carbohydrate interactions on model membrane surfaces, particularly in the context of virus binding, but also suggest a possible role of human intestinal GSLs as potential receptors for norovirus uptake.

  1. Evaluation of the RIDAGENE real-time PCR assay for the detection of GI and GII norovirus.

    PubMed

    Dunbar, N L; Bruggink, L D; Marshall, J A

    2014-07-01

    The current study examined the efficacy of the RIDAGENE norovirus (NoV) real-time polymerase chain reaction assay (R-Biopharm, Darmstadt, Germany) for use in a routine diagnostic laboratory. The RIDAGENE assay had an overall sensitivity of 98% but was more sensitive for GII than GI NoV. The assay had a specificity of 98%. The RIDAGENE assay could detect a variety of GI and GII open reading frame 2 genotypes including GI.1, GI.3, GI.8, GI.13, GII.2, GII.3, GII.4 (including the following variants: 2006b, 2009, 2012, and 3 others that have not been assigned), GII.6, GII.12, and GII.13. The assay did not cross react with a number of gastroenteritis viruses including adenovirus, astrovirus, rotavirus, and sapovirus. The assay was straightforward to perform, and for a run of 50 specimens, a result was obtainable in roughly 4 hours. The RIDAGENE assay can be recommended as a valuable detection method for NoV. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Genetic and evolutionary characterization of norovirus from sewage and surface waters in Córdoba City, Argentina.

    PubMed

    Blanco Fernández, María D; Torres, Carolina; Martínez, Laura C; Giordano, Miguel O; Masachessi, Gisela; Barril, Patricia A; Isa, María B; Campos, Rodolfo H; Nates, Silvia V; Mbayed, Viviana A

    2011-10-01

    Noroviruses (NoVs) are among the most common viral agents that cause gastroenteritis in humans of all ages worldwide. They are excreted in the feces and introduced into environmental waters as raw or treated sewage. In this work, sewage and water samples collected from the Suquía River in the city of Córdoba, Argentina, were evaluated for the presence of NoV. Phylogenetic analysis demonstrated that the main genotype detected was GII.4, belonging to the widely-distributed 2006b variant, followed by strains related to the putative recombinant GII.g virus. Detected NoVs were more phylogenetically related with recent viruses from other countries than with previous local sequences, suggesting a rapid and wide spread of viral strains that prevents a geographically structured phylogeny. A Bayesian coalescent analysis demonstrated that variants isolated in this work have a most recent common ancestor placed in 2007-2008 with estimated substitution rates of 3.7-5.8×10(-3)s/s/y. Environmental samples showed a mixture of both viral types, pointing up to the co-circulation and the risk of mixed infections and recombination. This is the first report on the detection and characterization of NoV in sewage and river water in Argentina.

  3. A novel norovirus GII.17 lineage contributed to adult gastroenteritis in Shanghai, China, during the winter of 2014–2015

    PubMed Central

    Chen, Haili; Qian, Fangxing; Xu, Jin; Chan, Martin; Shen, Zhen; Zai, Shubei; Shan, Menglin; Cai, Jinfeng; Zhang, Wanju; He, Jing; Liu, Yi; Zhang, Jun; Yuan, Zhenghong; Zhu, Zhaoqin; Hu, Yunwen

    2015-01-01

    Norovirus (NoV) is now recognized as a leading cause of nonbacterial acute gastroenteritis; however, the NoV GII.17 genotype has rarely been reported as the predominant genotype in clinical diarrhea cases. During the winter of 2014–2015, the GII.17 genotype, together with the NoV GII.4 genotype, dominated in sporadic adult patients with gastroenteritis in Shanghai. Phylogenetic analysis based on full-length VP1 amino acid sequences showed that the GII.17 strains that emerged in Shanghai have close evolutionary relationships with strains recently collected in the Hong Kong area, Guangdong province of China, and Japan during the same period. This cluster in the phylogenetic tree may represent a novel NoV GII.17 lineage recently circulating in East Asia. Pairwise distances between clusters also revealed the evolution of the NoV GII.17 genotype in previous decades. Our study emphasizes the importance of combined surveillance of NoV-associated infections. PMID:26975060

  4. Identifying Carbohydrate Ligands of a Norovirus P Particle using a Catch and Release Electrospray Ionization Mass Spectrometry Assay

    NASA Astrophysics Data System (ADS)

    Han, Ling; Kitova, Elena N.; Tan, Ming; Jiang, Xi; Klassen, John S.

    2014-01-01

    Noroviruses (NoVs), the major cause of epidemic acute gastroenteritis, recognize human histo-blood group antigens (HBGAs), which are present as free oligosaccharides in bodily fluid or glycolipids and glycoproteins on the surfaces of cells. The subviral P particle formed by the protruding (P) domain of the NoV capsid protein serves as a useful model for the study NoV-HBGA interactions. Here, we demonstrate the application of a catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) assay for screening carbohydrate libraries against the P particle to rapidly identify NoV ligands and potential inhibitors. Carbohydrate libraries of 50 and 146 compounds, which included 18 and 24 analogs of HBGA receptors, respectively, were screened against the P particle of VA387, a member of the predominant GII.4 NoVs. Deprotonated ions corresponding to the P particle bound to carbohydrates were isolated and subjected to collision-induced dissociation to release the ligands in their deprotonated forms. The released ligands were identified by ion mobility separation followed by mass analysis. All 13 and 16 HBGA ligands with intrinsic affinities >500 M-1 were identified in the 50 and the 146 compound libraries, respectively. Furthermore, screening revealed interactions with a series of oligosaccharides with structures found in the cell wall of mycobacteria and human milk. The affinities of these newly discovered ligands are comparable to those of the HBGA receptors, as estimated from the relative abundance of released ligand ions.

  5. Analysis of norovirus contamination of seafood

    USDA-ARS?s Scientific Manuscript database

    The study of human norovirus (NoVs) replication in vitro would be a highly useful tool to virologists and immunologists. For this reason, we have searched for new approaches to determine viability of noroviruses in food samples (especially sea food). Our research team has multiple years of experie...

  6. Molecular epidemiology of norovirus in South Korea

    PubMed Central

    Lee, Sung-Geun; Cho, Han-Gil; Paik, Soon-Young

    2015-01-01

    Norovirus is a major cause of viral gastroenteritis and a common cause of foodborne and waterborne outbreaks. Norovirus outbreaks are responsible for economic losses, most notably to the public health and food industry field. Norovirus has characteristics such as low infectious dose, prolonged shedding period, strong stability, great diversity, and frequent genome mutations. Besides these characteristics, they are known for rapid and extensive spread in closed settings such as hospitals, hotels, and schools. Norovirus is well known as a major agent of food-poisoning in diverse settings in South Korea. For these reasons, nationwide surveillance for norovirus is active in both clinical and environmental settings in South Korea. Recent studies have reported the emergence of variants and novel recombinants of norovirus. In this review, we summarized studies on the molecular epidemiology and nationwide surveillance of norovirus in South Korea. This review will provide information for vaccine development and prediction of new emerging variants of norovirus in South Korea. [BMB Reports 2015; 48(2): 61-67] PMID:25441425

  7. Murine Norovirus: Propagation, Quantification and Genetic Manipulation

    PubMed Central

    Hwang, Seungmin; Alhatlani, Bader; Arias, Armando; Caddy, Sarah L; Christodoulou, Constantina; Cunha, Juliana; Emmott, Ed; Gonzalez-Hernandez, Marta; Kolawole, Abimbola; Lu, Jia; Rippinger, Christine; Sorgeloos, Frédéric; Thorne, Lucy; Vashist, Surender; Goodfellow, Ian

    2014-01-01

    Murine norovirus (MNV) is a positive-sense, plus-stranded RNA virus in the Caliciviridae family. It is the most common pathogen in biomedical research colonies. MNV is also related to the human noroviruses, which cause the majority of non-bacterial gastroenteritis worldwide. Like the human noroviruses, MNV is an enteric virus that replicates in the intestine and is transmitted by the fecal-oral route. MNV replicates in murine macrophages and dendritic cells in cells in culture and in the murine host. This virus is often used to study mechanisms in norovirus biology, because the human noroviruses are refractory to growth in cell culture. MNV combines the availability of a cell culture and reverse genetics system with the ability to study infection in the native host. Herein, we describe a panel of techniques that are commonly used to study MNV biology. PMID:24789596

  8. The Effect of Malnutrition on Norovirus Infection

    PubMed Central

    Hickman, Danielle; Jones, Melissa K.; Zhu, Shu; Kirkpatrick, Ericka; Ostrov, David A.; Wang, Xiaoyu; Ukhanova, Maria; Sun, Yijun; Mai, Volker; Salemi, Marco; Karst, Stephanie M.

    2014-01-01

    ABSTRACT Human noroviruses are the primary cause of severe childhood diarrhea in the United States, and they are of particular clinical importance in pediatric populations in the developing world. A major contributing factor to the general increased severity of infectious diseases in these regions is malnutrition—nutritional status shapes host immune responses and the composition of the host intestinal microbiota, both of which can influence the outcome of pathogenic infections. In terms of enteric norovirus infections, mucosal immunity and intestinal microbes are likely to contribute to the infection outcome in substantial ways. We probed these interactions using a murine model of malnutrition and murine norovirus infection. Our results reveal that malnutrition is associated with more severe norovirus infections as defined by weight loss, impaired control of norovirus infections, reduced antiviral antibody responses, loss of protective immunity, and enhanced viral evolution. Moreover, the microbiota is dramatically altered by malnutrition. Interestingly, murine norovirus infection also causes changes in the host microbial composition within the intestine but only in healthy mice. In fact, the infection-associated microbiota resembles the malnutrition-associated microbiota. Collectively, these findings represent an extensive characterization of a new malnutrition model of norovirus infection that will ultimately facilitate elucidation of the nutritionally regulated host parameters that predispose to more severe infections and impaired memory immune responses. In a broad sense, this model may provide insight into the reduced efficacy of oral vaccines in malnourished hosts and the potential for malnourished individuals to act as reservoirs of emergent virus strains. PMID:24595373

  9. Norovirus diversity in diarrheic children from an African-descendant settlement in Belém, Northern Brazil.

    PubMed

    Aragão, Glicélia Cruz; Mascarenhas, Joana D'Arc Pereira; Kaiano, Jane Haruko Lima; de Lucena, Maria Silvia Sousa; Siqueira, Jones Anderson Monteiro; Fumian, Túlio Machado; Hernandez, Juliana das Mercês; de Oliveira, Consuelo Silva; Oliveira, Darleise de Souza; Araújo, Eliete da Cunha; Soares, Luana da Silva; Linhares, Alexandre Costa; Gabbay, Yvone Benchimol

    2013-01-01

    Norovirus (NoV), sapovirus (SaV) and human astrovirus (HAstV) are viral pathogens that are associated with outbreaks and sporadic cases of gastroenteritis. However, little is known about the occurrence of these pathogens in relatively isolated communities, such as the remnants of African-descendant villages ("Quilombola"). The objective of this study was the frequency determination of these viruses in children under 10 years, with and without gastroenteritis, from a "Quilombola" Community, Northern Brazil. A total of 159 stool samples were obtained from April/2008 to July/2010 and tested by an enzyme immunoassay (EIA) and reverse transcription-polymerase chain reaction (RT-PCR) to detect NoV, SaV and HAstV, and further molecular characterization was performed. These viruses were detected only in the diarrheic group. NoV was the most frequent viral agent detected (19.7%-16/81), followed by SaV (2.5%-2/81) and HAstV (1.2%-1/81). Of the 16 NoV-positive samples, 14 were sequenced with primers targeting the B region of the polymerase (ORF1) and the D region of the capsid (ORF2). The results showed a broad genetic diversity of NoV, with 12 strains being classified as GII-4 (5-41.7%), GII-6 (3-25%), GII-7 (2-16.7%), GII-17 (1-8.3%) and GI-2 (1-8.3%), as based on the polymerase region; 12 samples were classified, based on the capsid region, as GII-4 (6-50%, being 3-2006b variant and 3-2010 variant), GII-6 (3-25%), GII-17 (2-16.7%) and GII-20 (1-8.3%). One NoV-strain showed dual genotype specificity, based on the polymerase and capsid region (GII-7/GII-20). This study provides, for the first time, epidemiological and molecular information on the circulation of NoV, SaV and HAstV in African-descendant communities in Northern Brazil and identifies NoV genotypes that were different from those detected previously in studies conducted in the urban area of Belém. It remains to be determined why a broader NoV diversity was observed in such a semi-isolated community.

  10. Evaluation of Chlorine Treatment Levels on Inactivation of Human Norovirus and MS2 Bacteriophage during Sewage Treatment.

    PubMed

    Kingsley, David H; Fay, Johnna P; Calci, Kevin; Pouillot, Régis; Woods, Jacquelina; Chen, Haiqiang; Niemira, Brendan A; Van Doren, Jane M

    2017-09-22

    This study examined the inactivation of human norovirus (HuNoV) GI.1 and GII.4 by chlorine under conditions that mimic sewage treatment. Using a porcine gastric mucin-magnetic bead (PGM-MB) assay, no statistically significant loss in HuNoV binding (inactivation) was observed for secondary effluent treatments of ≤25 ppm total chlorine, while for both strains 50 and 100 ppm treatments resulted in ≤0.8 log10 and ≥3.9 log10 reductions, respectively. Treatments of 10, 25, 50, and 100 ppm chlorine inactivated 0.31, 1.35, >5, and >5 log10 of the norovirus indicator, MS2 bacteriophage, respectively. Evaluation of treatment time indicated that the vast majority of MS2 and HuNoV inactivation occurred in the first 5 min for 0.2-μm filtered, pre-chlorinated secondary effluent. Free chlorine measurements of secondary effluent seeded with MS2 and HuNoV demonstrated a substantial oxidative burden. For 25, 50, and 100 ppm treatments, free chlorine after 5 min exposure time ranged between 0.21-0.58, 0.28-16.7, and 11.6-53 ppm, respectively. At chlorine treatment levels of >50 ppm, statistically significant differences were observed between reductions for PGM-MB-bound HuNoV (potentially infectious) particles as compared with that for unbound (non-infectious) HuNoV particles or total norovirus particles. While results suggest that MS2 and HuNoV (as measured with PGM-MB binding) behave similarly, although not identically, both have limited susceptibility to chlorine treatments of ≤ 25 ppm total chlorine. Since sewage treatment is performed at ≤ 25 ppm total chlorine, targeting a free chlorine level of 0.5-1.0 ppm, these results suggest that traditional chlorine-based sewage treatment does not inactivate HuNoV efficiently.IMPORTANCE HuNoV is ubiquitous in sewage. A receptor binding assay was used to assess inactivation of HuNoV by chlorine-based sewage treatment given that the virus cannot be routinely propagated in vitro Results reported here indicate that chlorine

  11. Norovirus: U.S. Trends and Outbreaks

    MedlinePlus

    ... Norovirus outbreaks can also occur from fecal (stool) contamination of certain foods at their source. For example, oysters harvested from contaminated water and raspberries irrigated with contaminated water have caused ...

  12. Enterovirus and Norovirus Monitoring under UCMR3

    EPA Science Inventory

    This presentation describes the Unregulated Contaminant Monitoring Rule round 3 (UCMR3) monitoring program for enterovirus and norovirus in groundwater. It provides the data on microbial indicators and virus occurrence during the monitoring period. Enteric virus occurrence was ab...

  13. Noroviruses: a challenge for military forces.

    PubMed

    Delacour, H; Dubrous, P; Koeck, J L

    2010-12-01

    For military forces, the control of infectious acute gastroenteritis constitutes an old, constant and unsolved concern. Recent epidemiological studies suggest that the common bacterial causes are being overtaken by viruses. Norviruses are the most alarming group and norovirus outbreaks in military forces are regularly reported. Illness is generally mild and characterised by acute vomiting and diarrhoea, which lasts for a few days on average, but may be severe and potentially life-threatening in subjects who are already dehydrated due to daily activity. Moreover, outbreaks may diminish operational effectiveness. Prevention of norovirus infection currently relies on strict application of personal and collective hygiene rules including isolation of the cases, to the greatest possible extent. Although noroviruses are frequently mentioned as the cause of gastroenteritis outbreaks in troops deployed overseas, laboratory diagnosis is rarely done. So their real burden in military forces remains unclear and further epidemiological studies are required to determine the full impact of norovirus gastroenteritis on troops.

  14. Enterovirus and Norovirus Monitoring under UCMR3

    EPA Science Inventory

    This presentation describes the Unregulated Contaminant Monitoring Rule round 3 (UCMR3) monitoring program for enterovirus and norovirus in groundwater. It provides the data on microbial indicators and virus occurrence during the monitoring period. Enteric virus occurrence was ab...

  15. Innate Resistance and Susceptibility to Norovirus Infection

    SciTech Connect

    Nordgren, Johan; Sharma, Sumit; Kambhampati, Anita; Lopman, Ben; Svensson, Lennart; Dutch, Rebecca Ellis

    2016-04-26

    The notion that certain individuals appear more or less susceptible to infections or to specific microbes is not new, but, until recently, it was assumed that clinical outcome of an infection was mainly owing to virulence factors of the microorganism. Relatively little attention has been given to host genetic factors involved in innate or adaptive immunity or expression of pathogen receptors. A remarkable example of susceptibility dependence is the strong Mendelian trait resistance to the most common noroviruses among individuals with a nonsense mutation in chromosome 19. Norovirus is recognized as the leading cause of gastroenteritis worldwide, affecting children and adults alike. Noroviruses are highly contagious and genetically diverse RNA viruses, but not all individuals are susceptible to infection to the same norovirus genotypes. Presence of histo-blood group antigens (HBGAs) on gut epithelial surfaces is essential for susceptibility to many norovirus genotypes. The synthesis of these HBGAs, specifically of the ABH and Lewis families, requires the use of several fucosyl and glycosyltransferases encoded by the FUT2, FUT3, and ABH genes. Polymorphisms in these genes vary considerably depending on ethnicity, with a homozygous nonsense mutation (individuals called non-secretors) in the FUT2 gene occurring in approximately 5%–50% of different populations worldwide. Secretor status also affects gut microbiota composition, including HBGA-expressing bacteria and bacteria inducing fucosylation in the gut. These could be intermediary factors that govern norovirus susceptibility.

  16. Norovirus infection in primary immune deficiency.

    PubMed

    Brown, Li-An K; Clark, Ian; Brown, Julianne R; Breuer, Judith; Lowe, David M

    2017-03-08

    Norovirus is acknowledged to be a leading cause of acute gastroenteritis worldwide, and its importance as a cause of chronic infection in immune deficient hosts is increasingly recognised. Current evidence suggests that a coordinated response of innate immune mechanisms, CD8+ cytotoxicity and a humoral response, with CD4+ orchestration, is necessary for norovirus clearance. We explain how primary immune deficiency impairs these host defences and predisposes to chronic infection, associated with protracted diarrhoea, weight loss, and requirement for parenteral nutrition. The mucosal villous atrophy frequently seen in norovirus infection appears to be immune mediated, suggesting that some functional immune response is required in order for chronic norovirus infection to become symptomatic in primary immune deficiency. We provide a comprehensive summary of published cases of norovirus infection in patients with primary immune deficiency. Spontaneous viral clearance has been described; however, the majority of reported cases have had prolonged and severe illness. Treatment strategies are discussed in detail. Approaches that have been tried in patients with primary immune deficiency include exclusion diets, enteral and intravenous immunoglobulins, breast milk, immunosuppressants, ribavirin, and nitazoxanide. To date, only ribavirin has been used with apparent success to achieve clearance of chronic norovirus in primary immune deficiency, and randomised controlled trials are needed to evaluate a number of promising therapies that are discussed.

  17. Innate Resistance and Susceptibility to Norovirus Infection

    DOE PAGES

    Nordgren, Johan; Sharma, Sumit; Kambhampati, Anita; ...

    2016-04-26

    The notion that certain individuals appear more or less susceptible to infections or to specific microbes is not new, but, until recently, it was assumed that clinical outcome of an infection was mainly owing to virulence factors of the microorganism. Relatively little attention has been given to host genetic factors involved in innate or adaptive immunity or expression of pathogen receptors. A remarkable example of susceptibility dependence is the strong Mendelian trait resistance to the most common noroviruses among individuals with a nonsense mutation in chromosome 19. Norovirus is recognized as the leading cause of gastroenteritis worldwide, affecting children andmore » adults alike. Noroviruses are highly contagious and genetically diverse RNA viruses, but not all individuals are susceptible to infection to the same norovirus genotypes. Presence of histo-blood group antigens (HBGAs) on gut epithelial surfaces is essential for susceptibility to many norovirus genotypes. The synthesis of these HBGAs, specifically of the ABH and Lewis families, requires the use of several fucosyl and glycosyltransferases encoded by the FUT2, FUT3, and ABH genes. Polymorphisms in these genes vary considerably depending on ethnicity, with a homozygous nonsense mutation (individuals called non-secretors) in the FUT2 gene occurring in approximately 5%–50% of different populations worldwide. Secretor status also affects gut microbiota composition, including HBGA-expressing bacteria and bacteria inducing fucosylation in the gut. These could be intermediary factors that govern norovirus susceptibility.« less

  18. Therapeutics and Immunoprophylaxis against Noroviruses and Rotaviruses.

    PubMed

    Ghosh, Souvik; Malik, Yashpal Singh; Kobayashi, Nobumichi

    2017-09-12

    Noroviruses and rotaviruses are important viral etiologies of severe gastroenteritis. Noroviruses are the primary cause of non-bacterial diarrheal outbreaks in humans, whilst rotaviruses are a major cause of childhood diarrhea. Although both enteric pathogens substantially impact human health and economies, there are no approved drugs against noroviruses and rotaviruses, so far. On the other hand, whilst the currently licensed rotavirus vaccines have been successfully implemented in over 100 countries, the most advanced norovirus vaccine has recently completed phase-I and II trials. Technological advances coupled with proper understanding of viral morphology and replication over the past decade has facilitated pioneering research on therapeutics and immunoprophylaxis against noroviruses and rotaviruses, with promising outcomes in human clinical trials of some of the drugs and vaccines. Herein, we focus on the developments in the field of norovirus and rotavirus therapeutics and immunoprophylaxis, such as potential antiviral drug molecules, passive immunotherapies (oral human immunoglobulins, egg yolk and bovine colostral antibodies, llama-derived nanobodies, and antibodies expressed in probiotics, plants, rice grains and insect larvae), immune system modulators, probiotics, phytochemicals and other biological substances such as bovine milk proteins, therapeutic nanoparticles, hydrogels and viscogens, conventional viral vaccines (live and inactivated whole virus vaccines), and genetically engineered viral vaccines (reassortant viral particles, virus-like particles (VLPs) and other subunit recombinant vaccines including multi-valent viral vaccines, edible plant vaccines, and encapsulated viral particles). Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Ultrasensitive Norovirus Detection Using DNA Aptasensor Technology

    PubMed Central

    Giamberardino, Amanda; Labib, Mahmoud; Hassan, Eman M.; Tetro, Jason A.; Springthorpe, Susan; Sattar, Syed A.; Berezovski, Maxim V.; DeRosa, Maria C.

    2013-01-01

    DNA aptamers were developed against murine norovirus (MNV) using SELEX (Systematic Evolution of Ligands by EXponential enrichment). Nine rounds of SELEX led to the discovery of AG3, a promising aptamer with very high affinity for MNV as well as for lab-synthesized capsids of a common human norovirus (HuNoV) outbreak strain (GII.3). Using fluorescence anisotropy, AG3 was found to bind with MNV with affinity in the low picomolar range. The aptamer could cross-react with HuNoV though it was selected against MNV. As compared to a non-specific DNA control sequence, the norovirus-binding affinity of AG3 was about a million-fold higher. In further tests, the aptamer also showed nearly a million-fold higher affinity for the noroviruses than for the feline calicivirus (FCV), a virus similar in size and structure to noroviruses. AG3 was incorporated into a simple electrochemical sensor using a gold nanoparticle-modified screen-printed carbon electrode (GNPs-SPCE). The aptasensor could detect MNV with a limit of detection of approximately 180 virus particles, for possible on-site applications. The lead aptamer candidate and the aptasensor platform show promise for the rapid detection and identification of noroviruses in environmental and clinical samples. PMID:24244426

  20. Use of Murine Norovirus as a Surrogate To Evaluate Resistance of Human Norovirus to Disinfectants▿

    PubMed Central

    Belliot, Gaël; Lavaux, Amandine; Souihel, Donya; Agnello, Davide; Pothier, Pierre

    2008-01-01

    Murine norovirus (MNV) was used as a surrogate to study resistance of human norovirus to disinfectants used in hospitals. MNV was sensitive to alcohol, alcohol hand rubs, bleach, and povidone iodine-based disinfectant. Real-time reverse transcription-PCR results indicated that the presence of viral RNA did not correlate with the presence of infectious virus. PMID:18378650

  1. Experimental verification of the identity of variant-specific surface proteins in Giardia lamblia trophozoites.

    PubMed

    Li, Wei; Saraiya, Ashesh A; Wang, Ching C

    2013-05-21

    The cell membrane of a Giardia lamblia trophozoite is covered with a single species of variant-specific surface protein (VSP) that is replaced by another VSP every 6 to 13 generations of cell growth, possibly for an evasion of host immunity. Experimentally, only six VSP species have been verified to localize to the cell membrane thus far. By assuming that VSP contains multiple CXXC motifs, 219 vsp genes were annotated in GiardiaDB of the WB isolate. By further assuming that VSP possesses both CXXC motifs and a CRGKA tail at the C terminus, Adam et al. (BMC Genomics 11:424, 2010) identified a total of 303 potential vsp genes in Giardia WB. The discrepancies between these two assumed VSP identities have caused some confusion. Here, we used experimental approaches to further verify what is required of the structures of a VSP to localize to the surface of cell membrane. The data led to the following conclusions. (i) The C-terminal CRGKA sequence is not essential for localizing VSPs to the cell membrane. (ii) A "motif 1" of 45 residues, consisting of two CXXCs separated by 12 to 15 amino acid residues, located close to the C terminus and a hydrophobic "motif 2" of 38 residues at the C terminus are both essential and sufficient for localizing the protein to the cell membrane. (ii) An N-terminal sequence upstream from motif 1 is not required for targeting VSPs to the cell membrane. By these criteria, we are able to identify 73 open reading frames as the putative vsp genes in Giardia. IMPORTANCE The intestinal pathogen Giardia lamblia expresses only one variant-specific surface protein (VSP) on the cell membrane surface at a given time, but it changes spontaneously every 6 to 13 generations of growth, presumably for evading the host immunity. Only 6 VSPs have been empirically shown to localize to the cell membrane surface thus far. Here, we used mutations of VSPs and methods of identifying their locations in Giardia cells and found that a "motif 1" of 45 residues

  2. Self-Assembly of the Recombinant Capsid Protein of a Swine Norovirus into Virus-Like Particles and Evaluation of Monoclonal Antibodies Cross-Reactive with a Human Strain from Genogroup II▿

    PubMed Central

    Almanza, Horacio; Cubillos, Carolina; Angulo, Iván; Mateos, Francisco; Castón, José R.; van der Poel, Wim H. M.; Vinje, Jan; Bárcena, Juan; Mena, Ignacio

    2008-01-01

    Noroviruses (NoVs) are responsible for the majority of gastroenteritis outbreaks in humans. Recently, NoV strains which are genetically closely related to human genogroup II (GII) NoVs have been detected in fecal specimens from swine. These findings have raised concern about the possible role of pigs as reservoirs for NoVs that could infect humans. To better understand the epidemiology of swine NoVs in both the swine and the human populations, rapid immunoassays are needed. In this study, baculovirus recombinants were generated to express the capsid gene of a swine NoV GII genotype 11 (GII.11) strain which self-assembled into virus-like particles (VLPs). Subsequently, the purified VLPs were used to evoke monoclonal antibodies (MAbs) in mice. A panel of eight promising MAbs was obtained and evaluated for their ability to bind to heterologous VLPs, denaturated antigens, and truncated capsid proteins. The MAbs could be classified into two groups: two MAbs that recognized linear epitopes located at the amino-terminal half (shell domain) of the swine NoV GII.11 VLPs and that cross-reacted with human GII.4 NoV VLPs. The other six MAbs bound to conformational epitopes and did not cross-react with the human GII.4 VLPs. To our knowledge, this is the first report on the characterization of MAbs against swine NoVs. The swine NoV VLPs and the MAbs described here may be further used for the design of diagnostic reagents that could help increase our knowledge of the prevalence of NoV infections in pigs and the possible role of pigs as reservoirs for NoVs. PMID:18842943

  3. Identification of a variant-specific phosphorylation of TH2A during spermiogenesis

    PubMed Central

    Hada, Masashi; Masuda, Koji; Yamaguchi, Kosuke; Shirahige, Katsuhiko; Okada, Yuki

    2017-01-01

    Tissue-specific histone variant incorporation into chromatin plays dynamic and important roles in tissue development. Testis is one such tissue, and a number of testis-specific histone variants are expressed that have unique roles. While it is expected that such variants acquire post-transcriptional modifications to be functional, identification of variant-specific histone modifications is challenging because of the high similarity of amino acid sequences between canonical and variant versions. Here we identified a novel phosphorylation on TH2A, a germ cell-specific histone H2A variant. TH2A-Thr127 is unique to the variant and phosphorylated concomitant with chromatin condensation including spermiogenesis and early embryonic mitosis. In sperm chromatin, phosphorylated TH2A-Thr127 (=pTH2A) is co-localized with H3.3 at transcriptional starting sites of the genome, and subsequently becomes absent from the paternal genome upon fertilization. Notably, pTH2A is recurrent and accumulated in the pericentromeric heterochromatin of both paternal and maternal chromosomes in the first mitosis of embryos, suggesting its unique regulation during spermiogenesis and early embryogenesis. PMID:28387373

  4. Transmission of Norovirus Within Households in Quininde, Ecuador.

    PubMed

    Gastañaduy, Paul A; Vicuña, Yosselin; Salazar, Fabian; Broncano, Nely; Gregoricus, Nicole; Vinjé, Jan; Chico, Martha; Parashar, Umesh D; Cooper, Philip J; Lopman, Ben

    2015-09-01

    We studied the transmission of norovirus infection in households in Quininde, Ecuador. Among household contacts of norovirus positive children with diarrhea, norovirus negative children with diarrhea and asymptomatic controls, infection attack rates were 33%, 8% and 18%, respectively (N = 45, 36, 83). Infection attack rates were higher when index children had a higher viral load.

  5. Norovirus in feces and nasopharyngeal swab of children with and without acute gastroenteritis symptoms: First report of GI.5 in Brazil and GI.3 in nasopharyngeal swab.

    PubMed

    Dábilla, Nathânia; Nunes Vieira Almeida, Tâmera; Carvalho Rebouças Oliveira, Anniely; Kipnis, André; Neres Silva, Thairiny; Souza Fiaccadori, Fabíola; Teixeira de Sousa, Teresinha; de Paula Cardoso, Divina das Dôres; Souza, Menira

    2017-02-01

    Noroviruses (NoVs) are an important cause of acute gastroenteritis (AGE), worldwide. To evaluate the frequency, viral load and molecular profile of NoV in fecal and nasopharyngeal swab samples from hospitalized children, and to determine children's secretor status. From May 2014 to May 2015, 219 children were included in the study, 96 with gastroenteric symptoms and 123 without gastroenteric symptoms. All fecal and nasopharyngeal swab samples were screened by TaqMan RT-qPCR duplex (GI/GII NoV) and quality samples were characterized by genomic sequencing. Norovirus positivity rate in feces was 15.4% in asymptomatic and 18.8% in the symptomatic group. The median viral loads in feces were 2.69×10(8)GC/g and 4.32×10(7)GC/g from children with or without AGE symptoms, respectively. In nasopharyngeal swab samples, the NoV positivity was 11.4% in symptomatic children, with a median viral load of 2.20×10(7)GC/mL and 6.5% in asymptomatic children, with an average viral load of 1.73×10(6)GC/mL. In only two cases NoV was detected in both samples. A considerable genomic variability was observed in feces, with six genotypes being detected, as follows: GII.4, GII.6, GI.3 and GII.3, GI.2 and GI.5. Two GI.3 was detected in nasopharyngeal swab. Our data reveal considerable NoV frequencies in both nasopharyngeal and fecal samples from symptomatic and asymptomatic children. Higher viral loads were detected in samples from AGE symptomatic children, when compared to asymptomatic children. High genomic variability was observed, with this being the first report of GI.5 NoV in Brazil and of GI.3 in nasopharyngeal swab samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. In Vitro Proteolytic Processing of the MD145 Norovirus ORF1 Nonstructural Polyprotein Yields Stable Precursors and Products Similar to Those Detected in Calicivirus-Infected Cells

    PubMed Central

    Belliot, Gaël; Sosnovtsev, Stanislav V.; Mitra, Tanaji; Hammer, Carl; Garfield, Mark; Green, Kim Y.

    2003-01-01

    The MD145-12 strain (GII/4) is a member of the genus Norovirus in the Caliciviridae and was detected in a patient with acute gastroenteritis in a Maryland nursing home. The open reading frame 1 (ORF1) (encoding the nonstructural polyprotein) was cloned as a consensus sequence into various expression vectors, and a proteolytic cleavage map was determined. The virus-encoded cysteine proteinase mediated at least five cleavages (Q330/G331, Q696/G697, E875/G876, E1008/A1009, and E1189/G1190) in the ORF1 polyprotein in the following order: N-terminal protein; nucleoside triphosphatase; 20-kDa protein (p20); virus protein, genome linked (VPg); proteinase (Pro); polymerase (Pol). A time course analysis of proteolytic processing of the MD145-12 ORF1 polyprotein in an in vitro coupled transcription and translation assay allowed the identification of stable precursors and final mapped cleavage products. Stable precursors included p20VPg (analogous to the 3AB of the picornaviruses) and ProPol (analogous to the 3CD of the picornaviruses). Less stable processing intermediates were identified as p20VPgProPol, p20VPgPro, and VPgPro. The MD145-12 Pro and ProPol proteins were expressed in bacteria as active forms of the proteinase and used to further characterize their substrate specificities in trans cleavage assays. The MD145-12 Pro was able to cleave its five mapped cleavage sites in trans and, in addition, could mediate trans cleavage of the Norwalk virus (GI/I) ORF1 polyprotein into a similar proteolytic processing profile. Taken together, our data establish a model for proteolytic processing in the noroviruses that is consistent with nonstructural precursors and products identified in studies of caliciviruses that replicate in cell culture systems. PMID:14512545

  7. In vitro proteolytic processing of the MD145 norovirus ORF1 nonstructural polyprotein yields stable precursors and products similar to those detected in calicivirus-infected cells.

    PubMed

    Belliot, Gaël; Sosnovtsev, Stanislav V; Mitra, Tanaji; Hammer, Carl; Garfield, Mark; Green, Kim Y

    2003-10-01

    The MD145-12 strain (GII/4) is a member of the genus Norovirus in the Caliciviridae and was detected in a patient with acute gastroenteritis in a Maryland nursing home. The open reading frame 1 (ORF1) (encoding the nonstructural polyprotein) was cloned as a consensus sequence into various expression vectors, and a proteolytic cleavage map was determined. The virus-encoded cysteine proteinase mediated at least five cleavages (Q(330)/G(331), Q(696)/G(697), E(875)/G(876), E(1008)/A(1009), and E(1189)/G(1190)) in the ORF1 polyprotein in the following order: N-terminal protein; nucleoside triphosphatase; 20-kDa protein (p20); virus protein, genome linked (VPg); proteinase (Pro); polymerase (Pol). A time course analysis of proteolytic processing of the MD145-12 ORF1 polyprotein in an in vitro coupled transcription and translation assay allowed the identification of stable precursors and final mapped cleavage products. Stable precursors included p20VPg (analogous to the 3AB of the picornaviruses) and ProPol (analogous to the 3CD of the picornaviruses). Less stable processing intermediates were identified as p20VPgProPol, p20VPgPro, and VPgPro. The MD145-12 Pro and ProPol proteins were expressed in bacteria as active forms of the proteinase and used to further characterize their substrate specificities in trans cleavage assays. The MD145-12 Pro was able to cleave its five mapped cleavage sites in trans and, in addition, could mediate trans cleavage of the Norwalk virus (GI/I) ORF1 polyprotein into a similar proteolytic processing profile. Taken together, our data establish a model for proteolytic processing in the noroviruses that is consistent with nonstructural precursors and products identified in studies of caliciviruses that replicate in cell culture systems.

  8. Prevalence and diversity of norovirus genogroups I and II in Hong Kong marine waters and detection by real-time PCR.

    PubMed

    Yang, Ning; Qi, Huizhou; Wong, Minnie Man Lai; Wu, Rudolf Shiu Sun; Kong, Richard Yuen Chong

    2012-01-01

    Marine waters from six sites around Hong Kong with varying levels of sewage pollution were examined for noroviruses (NoVs) by PCR cloning and sequencing of a highly-variable N-terminal region of the VP1 capsid gene, at the ORF1-ORF2 junction of NoV. Phylogenetic analysis of genogroups GI- and GII-specific PCR clones obtained from different marine sites indicated that human NoV GI.1 and GII.4 strains are the most prevalent genotypes circulating in Hong Kong waters. GI- and GII-specific TaqMan-based real-time PCR assays targeting the ORF1-ORF2 junction of NoVs were used to quantify NoV particles in marine water samples in parallel with total Escherichia coli counts which were enumerated on TBX medium. No correlation of any significance between NoV and E. coli counts was observed which highlighted the inadequacy in using E. coli as a fecal indicator to predict the level of NoVs in marine waters to protect public health. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Comparison of nucleic acid extraction and reverse transcription-qPCR approaches for detection of GI and GII noroviruses in drinking water.

    PubMed

    Griffin, Shannon M; Brinkman, Nichole E; Hedrick, Elizabeth J; Rhodes, Eric R; Fout, G Shay

    2014-04-01

    The objective of this study was to compare three nucleic acid extraction and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) approaches for norovirus (NoV) detection in drinking water with respect to performance, costs, and analysis time. The approaches evaluated were: (A) an approach that utilizes the QIAamp DNA Blood Mini Kit and multiplex primers and probes for detection; (B) a procedure which includes the NucliSENS Magnetic Extraction Kit and other components of a proposed European Union standard method for NoV detection in foods; and (C) a commercialized assay which uses NucliSENS extraction and Cepheid SmartCycler® technologies. Each approach was evaluated by most probable number (MPN) analysis for detection of GI.1 and GII.4 NoVs from human stool. Furthermore, recoveries of spiked primary effluent in tap water concentrates were compared for each approach. Few significant differences were observed between approaches with regard to performance. However, Approach C was the most time consuming and expensive to perform. This research presents a case study of how molecular-based approaches for detection of NoVs can be compared and how various factors may play a role in which approach laboratories choose to employ. Published by Elsevier B.V.

  10. Delayed norovirus epidemic in the 2009-2010 season in Japan: potential relationship with intensive hand sanitizer use for pandemic influenza.

    PubMed

    Inaida, S; Shobugawa, Y; Matsuno, S; Saito, R; Suzuki, H

    2016-09-01

    Norovirus (NoV) epidemics normally peak in December in Japan; however, the peak in the 2009-2010 season was delayed until the fourth week of January 2010. We suspected intensive hand hygiene that was conducted for a previous pandemic influenza in 2009 as the cause of this delay. We analysed the NoV epidemic trend, based on national surveillance data, and its associations with monthly output data for hand hygiene products, including alcohol-based skin antiseptics and hand soap. The delayed peak in the NoV incidence in the 2009-2010 season had the lowest number of recorded cases of the five seasons studied (2006-2007 to 2010-2011). GII.4 was the most commonly occurring genotype. The monthly relative risk of NoV and monthly output of both alcohol-based skin antiseptics and hand soap were significantly and negatively correlated. Our findings suggest an association between hand hygiene using these products and prevention of NoV transmission.

  11. Enhanced hygiene measures and norovirus transmission during an outbreak.

    PubMed

    Heijne, Janneke C M; Teunis, Peter; Morroy, Gabriella; Wijkmans, Clementine; Oostveen, Sandy; Duizer, Erwin; Kretzschmar, Mirjam; Wallinga, Jacco

    2009-01-01

    Control of norovirus outbreaks relies on enhanced hygiene measures, such as handwashing, surface cleaning, using disposable paper towels, and using separate toilets for sick and well persons. However, little is known about their effectiveness in limiting further spread of norovirus infections. We analyzed norovirus outbreaks in 7 camps at an international scouting jamboree in the Netherlands during 2004. Implementation of hygiene measures coincided with an 84.8% (95% predictive interval 81.2%-86.6%) reduction in reproduction number. This reduction was unexpectedly large but still below the reduction needed to contain a norovirus outbreak. Even more stringent control measures are required to break the chain of transmission of norovirus.

  12. Bovine noroviruses: A missing component of calf diarrhoea diagnosis.

    PubMed

    Di Felice, Elisabetta; Mauroy, Axel; Pozzo, Fabiana Dal; Thiry, Damien; Ceci, Chiara; Di Martino, Barbara; Marsilio, Fulvio; Thiry, Etienne

    2016-01-01

    Noroviruses are RNA viruses that belong to the Genus Norovirus, Family Caliciviridae, and infect human beings and several animal species, including cattle. Bovine norovirus infections have been detected in cattle of a range of different ages throughout the world. Currently there is no suitable cell culture system for these viruses and information on their pathogenesis is limited. Molecular and serological tests have been developed, but are complicated by the high genetic and antigenic diversity of bovine noroviruses. Bovine noroviruses can be detected frequently in faecal samples of diarrhoeic calves, either alone or in association with other common enteric pathogens, suggesting a role for these viruses in the aetiology of calf enteritis.

  13. Identification of Variant-Specific Functions of PIK3CA by Rapid Phenotyping of Rare Mutations

    PubMed Central

    Dogruluk, Turgut; Tsang, Yiu Huen; Espitia, Maribel; Chen, Fengju; Chen, Tenghui; Chong, Zechen; Appadurai, Vivek; Dogruluk, Armel; Eterovic, Agna Karina; Bonnen, Penelope E.; Creighton, Chad J.; Chen, Ken; Mills, Gordon B.; Scott, Kenneth L.

    2015-01-01

    Large-scale sequencing efforts are uncovering the complexity of cancer genomes, which are comprised of causal “driver” mutations that promote tumor progression along with many more pathologically-neutral “passenger” events. The majority of mutations, both in known cancer drivers and uncharacterized genes, are generally of low occurrence, highlighting the need to functionally annotate the long tail of infrequent mutations present in heterogeneous cancers. Here we describe a mutation assessment pipeline enabled by high-throughput engineering of molecularly-barcoded gene variant expression clones identified by tumor sequencing. We first used this platform to functionally assess tail mutations observed in PIK3CA, which encodes the catalytic subunit alpha of the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) frequently mutated in cancer. Orthogonal screening for PIK3CA variant activity using in vitro and in vivo cell growth and transformation assays differentiated driver from passenger mutations, revealing that PIK3CA variant activity correlates imperfectly with its mutation frequency across breast cancer populations. While PIK3CA mutations with frequencies above 5% were significantly more oncogenic than wild-type in all assays, mutations occurring at 0.07 – 5.0% included those with and without oncogenic activities that ranged from weak to strong in at least one assay. Proteomic profiling coupled with therapeutic sensitivity assays on PIK3CA variant-expressing cell models revealed variant-specific activation of PI3K signaling as well as other pathways that include the MEK1/2 module of Mitogen-Activated Protein (MAP) Kinase pathway. Our data indicate that cancer treatments will need to increasingly consider the functional relevance of specific mutations in driver genes rather than considering all mutations in drivers as equivalent. PMID:26627007

  14. Structural Basis for Variant-Specific Neuroligin-Binding by α-Neurexin

    PubMed Central

    Tanaka, Hiroki; Nogi, Terukazu; Yasui, Norihisa; Iwasaki, Kenji; Takagi, Junichi

    2011-01-01

    Neurexins (Nrxs) are presynaptic membrane proteins with a single membrane-spanning domain that mediate asymmetric trans-synaptic cell adhesion by binding to their postsynaptic receptor neuroligins. α-Nrx has a large extracellular region comprised of multiple copies of laminin, neurexin, sex-hormone-binding globulin (LNS) domains and epidermal growth factor (EGF) modules, while that of β-Nrx has but a single LNS domain. It has long been known that the larger α-Nrx and the shorter β-Nrx show distinct binding behaviors toward different isoforms/variants of neuroligins, although the underlying mechanism has yet to be elucidated. Here, we describe the crystal structure of a fragment corresponding to the C-terminal one-third of the Nrx1α ectodomain, consisting of LNS5-EGF3-LNS6. The 2.3 Å-resolution structure revealed the presence of a domain configuration that was rigidified by inter-domain contacts, as opposed to the more common flexible “beads-on-a-string” arrangement. Although the neuroligin-binding site on the LNS6 domain was completely exposed, the location of the α-Nrx specific LNS5-EGF3 segment proved incompatible with the loop segment inserted in the B+ neuroligin variant, which explains the variant-specific neuroligin recognition capability observed in α-Nrx. This, combined with a low-resolution molecular envelope obtained by a single particle reconstruction performed on negatively stained full-length Nrx1α sample, allowed us to derive a structural model of the α-Nrx ectodomain. This model will help us understand not only how the large α-Nrx ectodomain is accommodated in the synaptic cleft, but also how the trans-synaptic adhesion mediated by α- and β-Nrxs could differentially affect synaptic structure and function. PMID:21552542

  15. Experimental Verification of the Identity of Variant-Specific Surface Proteins in Giardia lamblia Trophozoites

    PubMed Central

    Li, Wei; Saraiya, Ashesh A.; Wang, Ching C.

    2013-01-01

    ABSTRACT The cell membrane of a Giardia lamblia trophozoite is covered with a single species of variant-specific surface protein (VSP) that is replaced by another VSP every 6 to 13 generations of cell growth, possibly for an evasion of host immunity. Experimentally, only six VSP species have been verified to localize to the cell membrane thus far. By assuming that VSP contains multiple CXXC motifs, 219 vsp genes were annotated in GiardiaDB of the WB isolate. By further assuming that VSP possesses both CXXC motifs and a CRGKA tail at the C terminus, Adam et al. (BMC Genomics 11:424, 2010) identified a total of 303 potential vsp genes in Giardia WB. The discrepancies between these two assumed VSP identities have caused some confusion. Here, we used experimental approaches to further verify what is required of the structures of a VSP to localize to the surface of cell membrane. The data led to the following conclusions. (i) The C-terminal CRGKA sequence is not essential for localizing VSPs to the cell membrane. (ii) A “motif 1” of 45 residues, consisting of two CXXCs separated by 12 to 15 amino acid residues, located close to the C terminus and a hydrophobic “motif 2” of 38 residues at the C terminus are both essential and sufficient for localizing the protein to the cell membrane. (ii) An N-terminal sequence upstream from motif 1 is not required for targeting VSPs to the cell membrane. By these criteria, we are able to identify 73 open reading frames as the putative vsp genes in Giardia. PMID:23695837

  16. Plaque assay for murine norovirus.

    PubMed

    Gonzalez-Hernandez, Mariam B; Bragazzi Cunha, Juliana; Wobus, Christiane E

    2012-08-22

    Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture. Cell lysis and cytopathic effect (CPE) are observed during MNV-1 infection of murine dendritic cells or macrophages. This property of MNV-1 can be used to quantify the number of infectious particles in a given sample by performing a plaque assay. The plaque assay relies on the ability of MNV-1 to lyse cells and to form holes in a confluent cell monolayer, which are called plaques. Multiple techniques can be used to detect viral infections in tissue culture, harvested tissue, clinical, and environmental samples, but not all measure the number of infectious particles (e.g. qRT-PCR). One way to quantify infectious viral particles is to perform a plaque assay, which will be described in detail below. A variation on the MNV plaque assay is the fluorescent focus assay, where MNV antigen is immunostained in cell monolayers. This assay can be faster, since viral antigen expression precedes plaque formation. It is also useful for titrating viruses unable to form plaques. However, the fluorescent focus assay requires additional resources beyond those of the plaque assay, such as antibodies and a microscope to count focus-forming units. Infectious MNV can also be quantified by determining the 50% Tissue Culture Infective Dose (TCID50). This assay measures the amount of virus required to produce CPE in 50% of inoculated tissue culture cells by endpoint titration. However, its limit of detection is higher compared to a plaque assay. In this article, we describe a plaque assay protocol that can be used to effectively determine the number of infectious MNV particles present in biological or environmental samples. This method is based on the preparation of 10-fold serial dilutions of MNV-containing samples, which are used to inoculate a monolayer of permissive cells (RAW 264.7 murine macrophage cells). Virus is allowed to attach to the cell monolayer for a given period of

  17. Decoding norovirus infection in Crohn's disease.

    PubMed

    Chamaillard, Mathias; Cesaro, Annabelle; Lober, Pierre-Emmanuel; Hober, Didier

    2014-04-01

    Although a causing viral infectious agent remains untraceable in Crohn's disease, most recent genome-wide association studies have linked the FUT2 W143X mutation (resulting in asymptomatic norovirus infection) with the pathogenesis of Crohn's ileitis and with vitamin B12 deficiency (i.e., a known risk factor for Crohn's disease with ileal involvement). In line with these findings, host variations in additional genes involved in host response to norovirus infection (such as ATG16L1 and NOD2) predispose humans to Crohn's ileitis. One may therefore presume that asymptomatic norovirus infection may contribute to disruption of the stability of the gut microbiota leading to Crohn's ileitis. These paradigms highlight not only the need to revisit the potential transmissibility of Crohn's disease, but also potential safety issues of forthcoming clinical trials on human probiotic infusions in Crohn's ileitis by rigorous donors screening program.

  18. Rapid detection of norovirus in naturally contaminated food: foodborne gastroenteritis outbreak on a cruise ship in Brazil, 2010.

    PubMed

    Morillo, Simone Guadagnucci; Luchs, Adriana; Cilli, Audrey; do Carmo Sampaio Tavares Timenetsky, Maria

    2012-09-01

    Norovirus (NoV) is a prevalent pathogen of foodborne diseases; however, its detection in foods other than shellfish is often time consuming and unsuccessful. In 2010, an outbreak of acute gastroenteritis occurred on a cruise ship in Brazil, and NoV was the etiologic agent suspected. The objectives of this study were to report that a handy in-house methodology was suitable for NoV detection in naturally contaminated food, and perform the molecular characterization of food strains. Food samples (blue cheese, Indian sauce, herbal butter, soup, and white sauce) were analyzed by ELISA, two methods of RNA extraction, TRIzol(®) and QIAamp(®), following conventional RT-PCR. The qPCR was used in order to confirm the NoV genogroups. GI and GII NoV genogroups were identified by conventional RT-PCR after RNA extraction by means of the TRIzol(®) method. Two GII NoV samples were successfully sequenced, classified as GII.4; and they displayed a genetic relationship with strains from the Asian continent also isolated in 2010. GII and GI NoV were identified in distinct food matrices suggesting that it was not a common source of contamination. TRIzol(®) extraction followed by conventional RT-PCR was a suitable methodology in order to identify NoV in naturally contaminated food. Moreover, food samples could be processed within 8 h indicating the value of the method used for NoV detection, and its potential to identify foodborne gastroenteritis outbreaks in food products other than shellfish. This is the first description in Brazil of NoV detection in naturally contaminated food other than shellfish involved in a foodborne outbreak.

  19. Group a rotavirus and norovirus genotypes circulating in the northeastern Brazil in the post-monovalent vaccination era.

    PubMed

    Sá, Ana Caroline C; Gómez, Mariela M; Lima, Ila Fernanda N; Quetz, Josiane S; Havt, Alexandre; Oriá, Reinaldo B; Lima, Aldo A; Leite, José Paulo G

    2015-09-01

    Group A rotaviruses (RVA) and noroviruses (NoV) are the leading cause of acute gastroenteritis (AGE) worldwide. Childhood diarrhea deaths and hospital admissions have declined since the introduction of the monovalent (G1P[8]) vaccine (Rotarix(®) [RV1]) in the National Immunization Program in Brazil in 2006. This study aims to investigate the epidemiological profile of NoV and RVA infections from children with AGE in the Northeastern region of Brazil in the post vaccine season. Two-hundred fecal samples collected from children up to 10 years old in Fortaleza, Ceará between 2008-2009 were screened for the presence of RVA and NoV. Positive samples were genotyped and sequenced. The RVA screening revealed 12% prevalence and all RVA strains belonged to G2P[4] genotype. Phylogenetic analysis based on the 11 RVA genome segments sequenced from eight samples revealed a DS-1-like genotype constellation: I2-R2-C2-M2-A2-N2-T2-E2-H2. For NoV screening, the prevalence observed was 17% and the following genotypes were detected: GII.4 (59%), GII.12 (17%), GII.6 (9%), GII.3 (6%), and GII.? (9%). At least four different NoVs genotypes and two RVA G2P[4] variants were identified circulating in the Northeastern region of Brazil. RVA phylogenetic analysis suggests that the RVA G2P[4] strains might have originated from intragenogroup reassortment events. Whether the genetic modifications observed in these contemporary G2P[4] RVA strains may impact the long-term effectiveness of the current vaccination programs remains to be explored. These data reinforce the importance of surveillance for monitoring the emergence of new strains of RVA and NoV and their impact on cases of acute gastroenteritis.

  20. The South to North Variation of Norovirus Epidemics from 2006–07 to 2008–09 in Japan

    PubMed Central

    Inaida, Shinako; Shobugawa, Yugo; Matsuno, Shigeo; Saito, Reiko; Suzuki, Hiroshi

    2013-01-01

    Background Norovirus (NoV) is a major cause of gastroenteritis during the autumn and winter seasons in Japan as well as in other temperate climate regions. Most outbreaks are thought to occur by secondary attacks through person-to-person infection by fecal-oral route. Severe cases are found in young children or patients with chronic diseases. Clarifying the patterns of epidemic diffusion is important for considering effective monitoring and surveillance as well as possible prevention. Methods We considered the predominant viral genotype from the laboratory result obtained from Infectious Agents Surveillance Report (IASR) of National Institute of Infectious Diseases (NIID). We investigated the increase of NoV cases nationwide for the 2006–07 to 2008–09 seasons using sentinel gastroenteritis data collected from about 3000 pediatric clinics on National Epidemiological Surveillance of Infectious Diseases (NESID) acquired from the kriging method in the geographic information system (GIS). Results During these three seasons, the majority of the detected virus was GII.4, which ranged from 60.4 to 88.9%. The number of cases (per sentinel site) at the peak week was 22.81 in the 2006–07 season and it decreased in the following seasons. NoV cases began to increase earlier in the southern areas and gradually extended into the northern areas, similarly, over the seasons. The average period from when the increase of cases was detected in the southern area to when it reached the northern area was 12.7 weeks. Conclusion The decrease of the number of sentinel cases at the peak week may suggest the development of herd immunity after a period of high prevalence. Although the NoV epidemic is thought to be associated with cold weather, its cases first increased in the southern area with relatively warm temperature, indicating there are other climate factors involved. Geographic study using the sentinel data could enhance the monitoring and surveillance of and preparedness against

  1. Inactivation of human norovirus and Tulane virus in simple media and fresh whole strawberries by ionizing radiation.

    PubMed

    DiCaprio, Erin; Phantkankum, Nuttapong; Culbertson, Doug; Ma, Yuanmei; Hughes, John H; Kingsley, David; Uribe, Roberto M; Li, Jianrong

    2016-09-02

    Human norovirus (NoV) is a major cause of fresh produce-associated outbreaks and human NoV in irrigation water can potentially lead to viral internalization in fresh produce. Therefore, there is a need to develop novel intervention strategies to target internalized viral pathogens while maintaining fresh produce quality. In this study electron beam (E-beam) and gamma radiation were evaluated for efficacy against a human NoV GII.4 strain and Tulane virus (TV). Virus survival following ionizing radiation treatments was determined using direct quantitative reverse transcriptase PCR (RT-qPCR), the porcine gastric mucin magnetic bead (PGM-MB) binding assay followed by RT-qPCR, and plaque assay. In simple media, a high dose of E-beam treatment was required to completely abolish the receptor binding ability of human NoV (35.3kGy) and TV (19.5-24.1kGy), as assessed using the PGM-MB binding assay. Both human NoV and TV were more susceptible to gamma irradiation than E-beam, requiring 22.4kGy to achieve complete inactivation. In whole strawberries, no human NoV or TV RNA was detected following 28.7kGy of E-beam treatment using the PGM-MB binding assay. Overall, human NoV and TV are highly resistant to ionizing radiation and therefore the technology may not be suitable to eliminate viruses in fresh produce at the currently approved levels. In addition, the PGM-MB binding assay is an improved method to detect viral infectivity compared to direct RT-qPCR. Copyright © 2016. Published by Elsevier B.V.

  2. High Protective Efficacy of Probiotics and Rice Bran against Human Norovirus Infection and Diarrhea in Gnotobiotic Pigs

    PubMed Central

    Lei, Shaohua; Ramesh, Ashwin; Twitchell, Erica; Wen, Ke; Bui, Tammy; Weiss, Mariah; Yang, Xingdong; Kocher, Jacob; Li, Guohua; Giri-Rachman, Ernawati; Trang, Nguyen Van; Jiang, Xi; Ryan, Elizabeth P.; Yuan, Lijuan

    2016-01-01

    Probiotics have been recognized as vaccine adjuvants and therapeutic agents to treat acute gastroenteritis in children. We previously showed that rice bran (RB) reduced human rotavirus diarrhea in gnotobiotic pigs. Human noroviruses (HuNoVs) are the major pathogens causing non-bacterial acute gastroenteritis worldwide. In this study, Lactobacillus rhamnosus GG (LGG) and Escherichia coli Nissle 1917 (EcN) were first screened for their ability to bind HuNoV P particles and virions derived from clinical samples containing HuNoV genotype GII.3 and GII.4, then the effects of LGG+EcN and RB on HuNoV infection and diarrhea were investigated using the gnotobiotic pig model. While LGG+EcN colonization inhibited HuNoV shedding, probiotic cocktail regimens in which RB feeding started 7 days prior to or 1 day after viral inoculation in the LGG+EcN colonized gnotobiotic pigs exhibited high protection against HuNoV diarrhea and shedding, characterized by significantly reduced incidence (89 versus 20%) and shorter mean duration of diarrhea (2.2 versus 0.2 days), as well as shorter mean duration of virus shedding (3.2 versus 1.0 days). In both probiotic cocktail groups, the diarrhea reduction rates were 78% compared with the control group, and diarrhea severity was reduced as demonstrated by the significantly lower cumulative fecal scores. The high protective efficacy of the probiotic cocktail regimens was attributed to stimulation of IFN-γ+ T cell responses, increased production of intestinal IgA and IgG, and maintenance of healthy intestinal morphology (manifested as longer villi compared with the control group). Therefore, probiotic cocktail regimens containing LGG+EcN and RB may represent highly efficacious strategies to prevent and treat HuNoV gastroenteritis, and potentially other human enteric pathogens. PMID:27853451

  3. Full-Genomic Analysis of a Human Norovirus Recombinant GII.12/13 Novel Strain Isolated from South Korea

    PubMed Central

    Han, Sang-ha; Cho, Han-Gil; Kang, Lae-Hyung; Lee, Sung-Geun; Ryu, Sang-Ryeol; Paik, Soon-Young

    2013-01-01

    Norovirus (NoV) genogroups I and II are frequently recognized as the main causes of acute gastroenteritis and outbreaks of non-bacterial foodborne diseases. Furthermore, variants and recombinant strains of this virus are continuously emerging worldwide. The aim of this study was to identify NoV strains and to investigate and characterize rare genotypes. Stool samples (n = 500) were collected from patients with symptoms of acute gastroenteritis in Korea between December 2004 and November 2007. For analysis of the samples, rapid genotype screening was performed using reverse transcriptase-polymerase chain reaction. Full sequencing, using a newly designed set of 12 primers, revealed GII-12/13 strain. The partial sequence of GII-12/13 strain was compared with published NoV (GII-1 - 14) sequences targeting RdRp and capsid regions using phylogenetic analysis with the SimPlot program, which could evaluate recombination breakpoints. SimPlot analysis was also performed with the strain GII-12/Gifu-96/JPN (AB045603) for the RdRp region and with GII-13/G5175B-83/AUS(DQ379714) for the capsid region. NoV was detected in 19 of the 500 stool samples (3.8%). Genogroup GII-4 was found most frequently (n = 9, 1.8%), followed by GII-3 (n = 4, 0.8%), GII-6 (n = 3, 0.6%), GI-6 (n = 2, 0.4%), and GII-12/13 (n = 1, 0.2%). Importantly, we identified a novel NoV recombinant strain, C9-439 (KF289337), indicating potential risks, which suggested that, recombination occurred in the region between open reading frames 1 and 2 of the GII-12/13 strain and that breakpoints occurred in the polymerase region. PMID:24391985

  4. High Protective Efficacy of Probiotics and Rice Bran against Human Norovirus Infection and Diarrhea in Gnotobiotic Pigs.

    PubMed

    Lei, Shaohua; Ramesh, Ashwin; Twitchell, Erica; Wen, Ke; Bui, Tammy; Weiss, Mariah; Yang, Xingdong; Kocher, Jacob; Li, Guohua; Giri-Rachman, Ernawati; Trang, Nguyen Van; Jiang, Xi; Ryan, Elizabeth P; Yuan, Lijuan

    2016-01-01

    Probiotics have been recognized as vaccine adjuvants and therapeutic agents to treat acute gastroenteritis in children. We previously showed that rice bran (RB) reduced human rotavirus diarrhea in gnotobiotic pigs. Human noroviruses (HuNoVs) are the major pathogens causing non-bacterial acute gastroenteritis worldwide. In this study, Lactobacillus rhamnosus GG (LGG) and Escherichia coli Nissle 1917 (EcN) were first screened for their ability to bind HuNoV P particles and virions derived from clinical samples containing HuNoV genotype GII.3 and GII.4, then the effects of LGG+EcN and RB on HuNoV infection and diarrhea were investigated using the gnotobiotic pig model. While LGG+EcN colonization inhibited HuNoV shedding, probiotic cocktail regimens in which RB feeding started 7 days prior to or 1 day after viral inoculation in the LGG+EcN colonized gnotobiotic pigs exhibited high protection against HuNoV diarrhea and shedding, characterized by significantly reduced incidence (89 versus 20%) and shorter mean duration of diarrhea (2.2 versus 0.2 days), as well as shorter mean duration of virus shedding (3.2 versus 1.0 days). In both probiotic cocktail groups, the diarrhea reduction rates were 78% compared with the control group, and diarrhea severity was reduced as demonstrated by the significantly lower cumulative fecal scores. The high protective efficacy of the probiotic cocktail regimens was attributed to stimulation of IFN-γ(+) T cell responses, increased production of intestinal IgA and IgG, and maintenance of healthy intestinal morphology (manifested as longer villi compared with the control group). Therefore, probiotic cocktail regimens containing LGG+EcN and RB may represent highly efficacious strategies to prevent and treat HuNoV gastroenteritis, and potentially other human enteric pathogens.

  5. Noroviral p-particles as an in vitro model to assess the interactions of noroviruses with probiotics.

    PubMed

    Rubio-del-Campo, Antonio; Coll-Marqués, José M; Yebra, María J; Buesa, Javier; Pérez-Martínez, Gaspar; Monedero, Vicente; Rodríguez-Díaz, Jesús

    2014-01-01

    Noroviruses (NoVs) are the main etiologic agents of acute epidemic gastroenteritis and probiotic bacteria have been reported to exert a positive effect on viral diarrhea. The protruding (P) domain from NoVs VP1 capsid protein has the ability to assemble into the so-called P-particles, which retain the binding ability to host receptors. We purified the P-domains from NoVs genotypes GI.1 and GII.4 as 6X(His)-tagged proteins and determined that, similar to native domains, they were structured into P-particles that were functional in the recognition of the specific glycoconjugated receptors, as established by surface plasmon resonance experiments. We showed that several lactic acid bacteria (probiotic and non-probiotic) and a Gram-negative probiotic strain have the ability to bind P-particles on their surfaces irrespective of their probiotic status. The binding of P-particles (GI.1) to HT-29 cells in the presence of selected strains showed that bacteria can inhibit P-particle attachment in competitive exclusion experiments. However, pre-treatment of cells with bacteria or adding bacteria to cells with already attached P-particles enhanced the retention of the particles. Although direct viral binding and blocking of viral receptors have been postulated as mechanisms of protection against viral infection by probiotic bacteria, these results highlight the need for a careful evaluation of this hypothesis. The work presented here investigates for the first time the probiotic-NoVs-host interactions and points up the NoVs P-particles as useful tools to overcome the absence of in vitro cellular models to propagate these viruses.

  6. A norovirus outbreak related to contaminated surfaces.

    PubMed

    Repp, Kimberly K; Hostetler, Trevor P; Keene, William E

    2013-07-15

    We investigated an outbreak of norovirus infection affecting 12 of 16 auto dealership employees (75%) subsequent to a staff meeting. Take-out sandwiches initially seemed the likely source, but a cohort study found no association between illness and food consumption. Employees reported seeing a toddler with diarrhea in a dealership restroom shortly before the luncheon. Indistinguishable norovirus was isolated from employees and the child (genotype GII6.C) and from a diaper-changing station in the restroom (genogroup GII). Counterintuitively, this point-source outbreak following a meal was caused by environmental exposures, not food. Environmental exposures should be considered even in routine outbreak investigations.

  7. Identification of immune and viral correlates of norovirus protective immunity through comparative study of intra-cluster norovirus strains.

    PubMed

    Zhu, Shu; Regev, Doron; Watanabe, Makiko; Hickman, Danielle; Moussatche, Nissin; Jesus, Desyree Murta; Kahan, Shannon M; Napthine, Sawsan; Brierley, Ian; Hunter, Robert N; Devabhaktuni, Divya; Jones, Melissa K; Karst, Stephanie M

    2013-01-01

    Whether or not primary norovirus infections induce protective immunity has become a controversial issue, potentially confounded by the comparison of data from genetically distinct norovirus strains. Early human volunteer studies performed with a norovirus-positive inoculum initially led to the conclusion that primary infection does not generate long-term, protective immunity. More recently though, the epidemiological pattern of norovirus pandemics has led to the extrapolation that primary norovirus infection induces herd immunity. While these are seemingly discordant observations, they may in fact reflect virus strain-, cluster-, or genogroup-specific differences in protective immunity induction. Here, we report that highly genetically related intra-cluster murine norovirus strains differ dramatically in their ability to induce a protective immune response: Primary MNV-3 infection induced robust and cross-reactive protection, whereas primary MNV-1 infection induced modest homotypic and no heterotypic protection. In addition to this fundamental observation that intra-cluster norovirus strains display remarkable differences in protective immunity induction, we report three additional important observations relevant to norovirus:host interactions. First, antibody and CD4⁺ T cells are essential to controlling secondary norovirus infections. Second, the viral minor structural protein VP2 regulates the maturation of antigen presenting cells and protective immunity induction in a virus strain-specific manner, pointing to a mechanism by which MNV-1 may prevent the stimulation of memory immune responses. Third, VF1-mediated regulation of cytokine induction also correlates with protective immunity induction. Thus, two highly genetically-related norovirus strains displayed striking differences in induction of protective immune responses, strongly suggesting that the interpretation of norovirus immunity and vaccine studies must consider potential virus strain

  8. Norovirus: targets and tools in antiviral drug discovery.

    PubMed

    Rocha-Pereira, Joana; Neyts, Johan; Jochmans, Dirk

    2014-09-01

    The development of antiviral strategies to treat or prevent norovirus infections is a pressing matter. Noroviruses are the number 1 cause of acute gastroenteritis, of foodborne illness, of sporadic gastroenteritis in all age groups and of severe acute gastroenteritis in children less than 5 years old seeking medical assistance [USA/CDC]. In developing countries, noroviruses are linked to significant mortality (~200,000 children <5 years old). Noroviruses are a major culprit for the closure of hospital wards, and associated with increased hospitalization and mortality among the elderly. Transplant patients have significant risk of acquiring persistent norovirus gastroenteritis. Control and prevention strategies are limited to the use of disinfectants and hand sanitizers, whose efficacy is frequently insufficient. Hence, there is an ample need for antiviral treatment and prophylaxis of norovirus infections. The fact that only a handful of inhibitors of norovirus replication have been reported can largely be attributable to the hampering inability to cultivate human noroviruses in cell culture. The Norwalk replicon-bearing cells and the murine norovirus-infected cell lines are the available models to assess in vitro antiviral activity of compounds. Human noroviruses have been shown to replicate (to some extent) in mice, calves, gnotobiotic pigs, and chimpanzees. Infection of interferon-deficient mice with the murine norovirus results in virus-induced diarrhea. Here we review recent developments in understanding which norovirus proteins or host cell factors may serve as targets for inhibition of viral replication. Given the recent advances, significant progress in the search for antiviral strategies against norovirus infections is expected in the upcoming years. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Evaluation of a Microarray for Genotyping Noroviruses

    EPA Science Inventory

    Noroviruses that infect humans are divided into three genogroups based upon their sequence diversity. Of these, genogroups I and II have been identified as leading causes of waterborne disease outbreaks worldwide and are frequently found in rivers and lakes that serve as drinkin...

  10. Evaluation of a Microarray for Genotyping Noroviruses

    EPA Science Inventory

    Noroviruses that infect humans are divided into three genogroups based upon their sequence diversity. Of these, genogroups I and II have been identified as leading causes of waterborne disease outbreaks worldwide and are frequently found in rivers and lakes that serve as drinkin...

  11. Norovirus in Captive Lion Cub (Panthera leo)

    PubMed Central

    Campolo, Marco; Lorusso, Eleonora; Cavicchio, Paolo; Camero, Michele; Bellacicco, Anna L.; Decaro, Nicola; Elia, Gabriella; Greco, Grazia; Corrente, Marialaura; Desario, Costantina; Arista, Serenella; Banyai, Krisztián; Koopmans, Marion; Buonavoglia, Canio

    2007-01-01

    African lions (Panthera leo) are susceptible to viral diseases of domestic carnivores, including feline calicivirus infection. We report the identification of a novel enteric calicivirus, genetically related to human noroviruses of genogroup IV, in a lion cub that died of severe hemorrhagic enteritis. PMID:18214183

  12. Inactivation of human norovirus using chemical sanitizers

    USDA-ARS?s Scientific Manuscript database

    The porcine gastric mucin binding magnetic bead (PGM-MB) assay was used to evaluate the ability of chlorine, chlorine dioxide, peroxyacetic acid, hydrogen peroxide, and trisodium phosphate to inactivate human norovirus within 10 percent stool filtrate. One min free chlorine treatments at concentrat...

  13. Global Economic Burden of Norovirus Gastroenteritis

    PubMed Central

    Bartsch, Sarah M.; Lopman, Benjamin A.; Ozawa, Sachiko; Hall, Aron J.; Lee, Bruce Y.

    2016-01-01

    Background Despite accounting for approximately one fifth of all acute gastroenteritis illnesses, norovirus has received comparatively less attention than other infectious pathogens. With several candidate vaccines under development, characterizing the global economic burden of norovirus could help funders, policy makers, public health officials, and product developers determine how much attention and resources to allocate to advancing these technologies to prevent and control norovirus. Methods We developed a computational simulation model to estimate the economic burden of norovirus in every country/area (233 total) stratified by WHO region and globally, from the health system and societal perspectives. We considered direct costs of illness (e.g., clinic visits and hospitalization) and productivity losses. Results Globally, norovirus resulted in a total of $4.2 billion (95% UI: $3.2–5.7 billion) in direct health system costs and $60.3 billion (95% UI: $44.4–83.4 billion) in societal costs per year. Disease amongst children <5 years cost society $39.8 billion, compared to $20.4 billion for all other age groups combined. Costs per norovirus illness varied by both region and age and was highest among adults ≥55 years. Productivity losses represented 84–99% of total costs varying by region. While low and middle income countries and high income countries had similar disease incidence (10,148 vs. 9,935 illness per 100,000 persons), high income countries generated 62% of global health system costs. In sensitivity analysis, the probability of hospitalization had the largest impact on health system cost estimates ($2.8 billion globally, assuming no hospitalization costs), while the probability of missing productive days had the largest impact on societal cost estimates ($35.9 billion globally, with a 25% probability of missing productive days). Conclusions The total economic burden is greatest in young children but the highest cost per illness is among older age

  14. Recurring norovirus transmission on an airplane.

    PubMed

    Thornley, Craig N; Emslie, Nicola A; Sprott, Tim W; Greening, Gail E; Rapana, Jackie P

    2011-09-01

    Previously reported outbreaks of norovirus gastroenteritis associated with aircraft have been limited to transmission during a single flight sector. During October 2009, an outbreak of diarrhea and vomiting occurred among different groups of flight attendants who had worked on separate flight sectors on the same airplane. We investigated the cause of the outbreak and whether the illnesses were attributable to work on the airplane. Information was obtained from flight attendants on demographic characteristics, symptoms, and possible transmission risk factors. Case patients were defined as flight attendants with diarrhea or vomiting <51 hours after the end of their first flight sector on the airplane during 13-18 October 2009. Stool samples were tested for norovirus RNA. A passenger had vomited on the Boeing 777-200 airplane on the 13 October flight sector. Sixty-three (82%) of 77 flight attendants who worked on the airplane during 13-18 October provided information, and 27 (43%) met the case definition. The attack rate among flight attendants decreased significantly over successive flight sectors from 13 October onward (P < .001). Working as a supervisor was independently associated with development of illness (adjusted odds ratio, 5.8; 95% confidence interval, 1.3-25.6). Norovirus genotype GI.6 was detected in stool samples from 2 case patients who worked on different flight sectors. Sustained transmission of norovirus is likely to have occurred because of exposures on this airplane during successive flight sectors. Airlines should make provision for adequate disinfection of airplanes with use of products effective against norovirus and other common infectious agents after vomiting has occurred.

  15. Inactivation of human norovirus using chemical sanitizers.

    PubMed

    Kingsley, David H; Vincent, Emily M; Meade, Gloria K; Watson, Clytrice L; Fan, Xuetong

    2014-02-03

    The porcine gastric mucin binding magnetic bead (PGM-MB) assay was used to evaluate the ability of chlorine, chlorine dioxide, peroxyacetic acid, hydrogen peroxide, and trisodium phosphate to inactivate human norovirus within 10% stool filtrate. One-minute free chlorine treatments at concentrations of 33 and 189 ppm reduced virus binding in the PGM-MB assay by 1.48 and 4.14 log₁₀, respectively, suggesting that chlorine is an efficient sanitizer for inactivation of human norovirus (HuNoV). Five minute treatments with 5% trisodium phosphate (pH~12) reduced HuNoV binding by 1.6 log₁₀, suggesting that TSP, or some other high pH buffer, could be used to treat food and food contact surfaces to reduce HuNoV. One minute treatments with 350 ppm chlorine dioxide dissolved in water did not reduce PGM-MB binding, suggesting that the sanitizer may not be suitable for HuNoV inactivation in liquid form. However a 60-min treatment with 350 ppm chlorine dioxide did reduce human norovirus by 2.8 log₁₀, indicating that chlorine dioxide had some, albeit limited, activity against HuNoV. Results also suggest that peroxyacetic acid has limited effectiveness against human norovirus, since 1-min treatments with up to 195 ppm reduced human norovirus binding by <1 log₁₀. Hydrogen peroxide (4%) treatment of up to 60 min resulted in minimal binding reduction (~0.1 log₁₀) suggesting that H₂O₂ is not a good liquid sanitizer for HuNoV. Overall this study suggests that HuNoV is remarkably resistant to several commonly used disinfectants and advocates for the use of chlorine (sodium hypochlorite) as a HuNoV disinfectant wherever possible.

  16. Advances in Laboratory Methods for Detection and Typing of Norovirus

    PubMed Central

    2014-01-01

    Human noroviruses are the leading cause of epidemic and sporadic gastroenteritis across all age groups. Although the disease is usually self-limiting, in the United States norovirus gastroenteritis causes an estimated 56,000 to 71,000 hospitalizations and 570 to 800 deaths each year. This minireview describes the latest data on laboratory methods (molecular, immunological) for norovirus detection, including real-time reverse transcription-quantitative PCR (RT-qPCR) and commercially available immunological assays as well as the latest FDA-cleared multi-gastrointestinal-pathogen platforms. In addition, an overview is provided on the latest nomenclature and molecular epidemiology of human noroviruses. PMID:24989606

  17. Virucidal Effectiveness Testing Using Feline Calicivirus as Surrogate for Norovirus

    EPA Pesticide Factsheets

    These documents describe the effectiveness test using Feline Calicivirus as Surrogate for Norovirus, including initial and confirmatory testing and testing with pre-saturated or impregnated towelettes.

  18. Structural Basis for Norovirus Inhibition and Fucose Mimicry by Citrate

    SciTech Connect

    Hansman, Grant S.; Shahzad-ul-Hussan, Syed; McLellan, Jason S.; Chuang, Gwo-Yu; Georgiev, Ivelin; Shimoike, Takashi; Katayama, Kazuhiko; Bewley, Carole A.; Kwong, Peter D.

    2012-01-20

    Human noroviruses bind with their capsid-protruding domains to histo-blood-group antigens (HBGAs), an interaction thought to direct their entry into cells. Although human noroviruses are the major cause of gastroenteritis outbreaks, development of antivirals has been lacking, mainly because human noroviruses cannot be cultivated. Here we use X-ray crystallography and saturation transfer difference nuclear magnetic resonance (STD NMR) to analyze the interaction of citrate with genogroup II (GII) noroviruses. Crystals of citrate in complex with the protruding domain from norovirus GII.10 Vietnam026 diffracted to 1.4 {angstrom} and showed a single citrate bound at the site of HBGA interaction. The citrate interaction was coordinated with a set of capsid interactions almost identical to that involved in recognizing the terminal HBGA fucose, the saccharide which forms the primary conserved interaction between HBGAs and GII noroviruses. Citrate and a water molecule formed a ring-like structure that mimicked the pyranoside ring of fucose. STD NMR showed the protruding domain to have weak affinity for citrate (460 {mu}M). This affinity, however, was similar to the affinities of the protruding domain for fucose (460 {mu}M) and H type 2 trisaccharide (390 {mu}M), an HBGA shown previously to be specifically recognized by human noroviruses. Importantly, competition STD NMR showed that citrate could compete with HBGA for norovirus binding. Together, the results suggest that citrate and other glycomimetics have the potential to block human noroviruses from binding to HBGAs.

  19. Structural basis for norovirus inhibition and fucose mimicry by citrate.

    PubMed

    Hansman, Grant S; Shahzad-Ul-Hussan, Syed; McLellan, Jason S; Chuang, Gwo-Yu; Georgiev, Ivelin; Shimoike, Takashi; Katayama, Kazuhiko; Bewley, Carole A; Kwong, Peter D

    2012-01-01

    Human noroviruses bind with their capsid-protruding domains to histo-blood-group antigens (HBGAs), an interaction thought to direct their entry into cells. Although human noroviruses are the major cause of gastroenteritis outbreaks, development of antivirals has been lacking, mainly because human noroviruses cannot be cultivated. Here we use X-ray crystallography and saturation transfer difference nuclear magnetic resonance (STD NMR) to analyze the interaction of citrate with genogroup II (GII) noroviruses. Crystals of citrate in complex with the protruding domain from norovirus GII.10 Vietnam026 diffracted to 1.4 Å and showed a single citrate bound at the site of HBGA interaction. The citrate interaction was coordinated with a set of capsid interactions almost identical to that involved in recognizing the terminal HBGA fucose, the saccharide which forms the primary conserved interaction between HBGAs and GII noroviruses. Citrate and a water molecule formed a ring-like structure that mimicked the pyranoside ring of fucose. STD NMR showed the protruding domain to have weak affinity for citrate (460 μM). This affinity, however, was similar to the affinities of the protruding domain for fucose (460 μM) and H type 2 trisaccharide (390 μM), an HBGA shown previously to be specifically recognized by human noroviruses. Importantly, competition STD NMR showed that citrate could compete with HBGA for norovirus binding. Together, the results suggest that citrate and other glycomimetics have the potential to block human noroviruses from binding to HBGAs.

  20. Heat-Denatured Lysozyme Inactivates Murine Norovirus as a Surrogate Human Norovirus.

    PubMed

    Takahashi, Hajime; Nakazawa, Moemi; Ohshima, Chihiro; Sato, Miki; Tsuchiya, Tomoki; Takeuchi, Akira; Kunou, Masaaki; Kuda, Takashi; Kimura, Bon

    2015-07-02

    Human norovirus infects humans through the consumption of contaminated food, contact with the excrement or vomit of an infected person, and through airborne droplets that scatter the virus through the air. Being highly infectious and highly viable in the environment, inactivation of the norovirus requires a highly effective inactivating agent. In this study, we have discovered the thermal denaturing capacity of a lysozyme with known antimicrobial activity against gram-positive bacteria, as well as its inactivating effect on murine norovirus. This study is the first report on the norovirus-inactivating effects of a thermally denatured lysozyme. We observed that lysozymes heat-treated for 40 min at 100 °C caused a 4.5 log reduction in infectivity of norovirus. Transmission electron microscope analysis showed that virus particles exposed to thermally denatured lysozymes were expanded, compared to the virus before exposure. The amino acid sequence of the lysozyme was divided into three sections and the peptides of each artificially synthesised, in order to determine the region responsible for the inactivating effect. These results suggest that thermal denaturation of the lysozyme changes the protein structure, activating the region responsible for imparting an inactivating effect against the virus.

  1. Asymptomatic Norovirus Infection in Mexican Children

    PubMed Central

    García, Coralith; DuPont, Herbert L.; Long, Kurt Z.; Santos, Jose I.; Ko, GwangPyo

    2006-01-01

    Sixty-three children in periurban Mexico City were examined for the occurrence of asymptomatic norovirus (NoV) infection from June to August 1998. NoV was detected in 48 of 161 stool specimens (29.8%), with 31 children (49.2%) having at least one positive stool. Asymptomatic NoV infection occurred commonly during summertime in a Mexican pediatric population. PMID:16891526

  2. Human Norovirus Aptamer Exhibits High Degree of Target Conformation-Dependent Binding Similar to That of Receptors and Discriminates Particle Functionality

    PubMed Central

    Bobay, Benjamin G.; Mertens, Brittany; Jaykus, Lee-Ann

    2016-01-01

    ABSTRACT Although two in vitro cultivation methods have been reported, discrimination of infectious human norovirus particles for study of viral inactivation is still a challenge, as both rely on reverse transcriptase quantitative PCR. Histo-blood group antigen (HBGA) binding assays serve as a proxy for estimation of infectious particles; however, they are costly and difficult to purify/modify. Some evidence suggests that certain nucleic acid aptamers only bind intact target proteins, thus displaying a high degree of conformation-dependent binding. The objective of this proof-of-concept study was to characterize the degree of conformation-dependent binding a human norovirus aptamer, M6-2, displayed with the capsid of the norovirus GII.4 Sydney (SYV) strain as a model. SYV capsids were exposed to heat, and aptamer, receptor (HBGA), and antibody binding was assessed. M6-2 and the receptor displayed similarly little target sequence-dependent binding (2.0% ± 1.3% and 0.5% ± 1.2% signal, respectively) compared to that of NS14 (26.4% ± 3.9%). The decay rates calculated with M6-2 and the receptor were also not statistically significantly different (P > 0.05), and dynamic light scattering and electron microscopy confirmed these observations. Ligand docking simulations revealed multiple distinct contacts of M6-2 in the N-terminal P1 and P2 domains of the viral capsid, with some residues close to receptor binding residues. These data suggest that single-stranded DNA aptamers like M6-2 display a high degree of target conformation-dependent binding. It is the first time nucleic acid aptamers have had this characteristic utilized and investigated to discern the infectivity status of viral particles, and the data suggest that other aptamers may show promise as valuable ligands in the study of other fastidious microorganisms. IMPORTANCE Human noroviruses impose a considerable health burden globally. However, study of their inactivation is still challenging with currently

  3. Identifying Potential Norovirus Epidemics in China via Internet Surveillance.

    PubMed

    Liu, Kui; Huang, Sichao; Miao, Zi-Ping; Chen, Bin; Jiang, Tao; Cai, Gaofeng; Jiang, Zhenggang; Chen, Yongdi; Wang, Zhengting; Gu, Hua; Chai, Chengliang; Jiang, Jianmin

    2017-08-08

    Norovirus is a common virus that causes acute gastroenteritis worldwide, but a monitoring system for norovirus is unavailable in China. We aimed to identify norovirus epidemics through Internet surveillance and construct an appropriate model to predict potential norovirus infections. The norovirus-related data of a selected outbreak in Jiaxing Municipality, Zhejiang Province of China, in 2014 were collected from immediate epidemiological investigation, and the Internet search volume, as indicated by the Baidu Index, was acquired from the Baidu search engine. All correlated search keywords in relation to norovirus were captured, screened, and composited to establish the composite Baidu Index at different time lags by Spearman rank correlation. The optimal model was chosen and possibly predicted maps in Zhejiang Province were presented by ArcGIS software. The combination of two vital keywords at a time lag of 1 day was ultimately identified as optimal (ρ=.924, P<.001). The exponential curve model was constructed to fit the trend of this epidemic, suggesting that a one-unit increase in the mean composite Baidu Index contributed to an increase of norovirus infections by 2.15 times during the outbreak. In addition to Jiaxing Municipality, Hangzhou Municipality might have had some potential epidemics in the study time from the predicted model. Although there are limitations with early warning and unavoidable biases, Internet surveillance may be still useful for the monitoring of norovirus epidemics when a monitoring system is unavailable.

  4. Lessons Learned from an Elementary School Norovirus Outbreak

    ERIC Educational Resources Information Center

    Gomez, Eileen Button

    2008-01-01

    Outbreaks of norovirus have been on the increase. The virus often spreads quickly through schools and similar institutions. The school nurse may be able to minimize the impact of a school norovirus outbreak by providing accurate information about the disease, the scope of the local situation, and instruction on infection control measures. This…

  5. EVALUATION OF A GENERIC ARRAY APPROACH FOR GENOTYPING NOROVIRUSES

    EPA Science Inventory

    Noroviruses are the leading cause of nonbacterial gastroenteritis outbreaks in the United States. Because of their potential to contaminate drinking water, the U.S Environmental Protection Agency has included noroviruses on the Contaminant Candidate List (CCL) to assess the publi...

  6. 21 CFR 866.3395 - Norovirus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Norovirus serological reagents. 866.3395 Section 866.3395 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3395 Norovirus...

  7. 21 CFR 866.3395 - Norovirus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Norovirus serological reagents. 866.3395 Section 866.3395 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3395 Norovirus...

  8. 21 CFR 866.3395 - Norovirus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Norovirus serological reagents. 866.3395 Section 866.3395 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3395 Norovirus...

  9. High pressure processing inactivates human norovirus within oysters

    USDA-ARS?s Scientific Manuscript database

    Consumption of raw bivalve mollusks can result in norovirus infection. One potential intervention for virus-contaminated shellfish is high pressure processing (HPP). Currently HPP is known to inactivate Vibrio bacteria, hepatitis A virus, and murine norovirus within oysters. To evaluate the potentia...

  10. Lessons Learned from an Elementary School Norovirus Outbreak

    ERIC Educational Resources Information Center

    Gomez, Eileen Button

    2008-01-01

    Outbreaks of norovirus have been on the increase. The virus often spreads quickly through schools and similar institutions. The school nurse may be able to minimize the impact of a school norovirus outbreak by providing accurate information about the disease, the scope of the local situation, and instruction on infection control measures. This…

  11. Identifying Potential Norovirus Epidemics in China via Internet Surveillance

    PubMed Central

    Chen, Bin; Jiang, Tao; Cai, Gaofeng; Jiang, Zhenggang; Chen, Yongdi; Wang, Zhengting; Gu, Hua; Chai, Chengliang

    2017-01-01

    Background Norovirus is a common virus that causes acute gastroenteritis worldwide, but a monitoring system for norovirus is unavailable in China. Objective We aimed to identify norovirus epidemics through Internet surveillance and construct an appropriate model to predict potential norovirus infections. Methods The norovirus-related data of a selected outbreak in Jiaxing Municipality, Zhejiang Province of China, in 2014 were collected from immediate epidemiological investigation, and the Internet search volume, as indicated by the Baidu Index, was acquired from the Baidu search engine. All correlated search keywords in relation to norovirus were captured, screened, and composited to establish the composite Baidu Index at different time lags by Spearman rank correlation. The optimal model was chosen and possibly predicted maps in Zhejiang Province were presented by ArcGIS software. Results The combination of two vital keywords at a time lag of 1 day was ultimately identified as optimal (ρ=.924, P<.001). The exponential curve model was constructed to fit the trend of this epidemic, suggesting that a one-unit increase in the mean composite Baidu Index contributed to an increase of norovirus infections by 2.15 times during the outbreak. In addition to Jiaxing Municipality, Hangzhou Municipality might have had some potential epidemics in the study time from the predicted model. Conclusions Although there are limitations with early warning and unavoidable biases, Internet surveillance may be still useful for the monitoring of norovirus epidemics when a monitoring system is unavailable. PMID:28790023

  12. EVALUATION OF A GENERIC ARRAY APPROACH FOR GENOTYPING NOROVIRUSES

    EPA Science Inventory

    Noroviruses are the leading cause of nonbacterial gastroenteritis outbreaks in the United States. Because of their potential to contaminate drinking water, the U.S Environmental Protection Agency has included noroviruses on the Contaminant Candidate List (CCL) to assess the publi...

  13. Norovirus GII.17 Natural Infections in Rhesus Monkeys, China

    PubMed Central

    He, Zhanlong; Liu, Bo; Tao, Yufen; Li, Chao; Xia, Ming; Zhong, Weiming; Jiang, Xi

    2017-01-01

    Noroviruses are a leading viral cause of acute gastroenteritis among humans. During the 2014–15 epidemic season, norovirus GII.17 was detected in rhesus monkeys in China. Genetic, structural, and challenge studies revealed virus mutations and verified the infections. Thus, cross-species transmission may occur, and monkeys may be a virus reservoir. PMID:28102802

  14. Noroviruses: The Principal Cause of Foodborne Disease Worldwide

    PubMed Central

    Koo, Hoonmo L.; Ajami, Nadim; Atmar, Robert L.; DuPont, Herbert L.

    2011-01-01

    Noroviruses are the leading cause of foodborne disease outbreaks worldwide, and may soon eclipse rotaviruses as the most common cause of severe pediatric gastroenteritis, as the use of rotavirus vaccines becomes more widespread. Genetic mutations and recombinations contribute to the broad heterogeneity of noroviruses and the emergence of new epidemic strains. Although typically a self-limited disease, norovirus gastroenteritis can cause significant morbidity and mortality among children, the elderly, and the immunocompromised. The lack of a cell culture or small animal model has hindered norovirus research and the development of novel therapeutic and preventative interventions. However, vaccines based on norovirus capsid protein virus-like particles are promising and may one day become widely available through transgenic expression in plants. PMID:20670600

  15. Multicenter Evaluation of the Xpert Norovirus Assay for Detection of Norovirus Genogroups I and II in Fecal Specimens

    PubMed Central

    Gonzalez, Mark D.; Langley, L. Claire; Faron, Matthew L.; Maier, Melanie; Templeton, Kate; Walker, Kimberly; Popowitch, Elena B.; Miller, Melissa B.; Rao, Arundhati; Liebert, Uwe G.; Ledeboer, Nathan A.; Vinjé, Jan

    2015-01-01

    Norovirus is the most common cause of sporadic gastroenteritis and outbreaks worldwide. The rapid identification of norovirus has important implications for infection prevention measures and may reduce the need for additional diagnostic testing. The Xpert Norovirus assay recently received FDA clearance for the detection and differentiation of norovirus genogroups I and II (GI and GII), which account for the vast majority of infections. In this study, we evaluated the performance of the Xpert Norovirus assay with both fresh, prospectively collected (n = 914) and frozen, archived (n = 489) fecal specimens. A Centers for Disease Control and Prevention (CDC) composite reference method was used as the gold standard for comparison. For both prospective and frozen specimens, the Xpert Norovirus assay showed positive percent agreement (PPA) and negative percent agreement (NPA) values of 98.3% and 98.1% for GI and of 99.4% and 98.2% for GII, respectively. Norovirus prevalence in the prospective specimens (collected from March to May of 2014) was 9.9% (n = 90), with the majority of positives caused by genogroup II (82%, n = 74). The positive predictive value (PPV) of the Xpert Norovirus assay was 75% for GI-positive specimens, whereas it was 86.5% for GII-positive specimens. The negative predictive values (NPV) for GI and GII were 100% and 99.9%, respectively. PMID:26560532

  16. Outbreak of norovirus illness in a college summer camp: impact of cleaning on occurrence of norovirus on fomites.

    PubMed

    Fankem, Sonia L M; Boone, Stephanie A; Gaither, Marlene; Gerba, Charles P

    2014-04-01

    During the summer of 2005 an outbreak of norovirus acute gastroenteritis occurred in a residential college summer camp and was reported to the local health department. The outbreak spread rapidly to several other groups concurrently sharing the same facilities. During the investigation, fomites were sampled at different times in dorm rooms and tested for norovirus. The number of norovirus-positive rooms increased after the first room cleaning, from 40% to 73%. After the initial cleaning, the staff was instructed on proper cleaning and disinfection procedures and provided with disposable disinfecting wipes to reduce cross contamination, and the number of norovirus-positive rooms decreased to 30%. These findings reinforce the need for appropriate cleaning and disinfection procedures during a norovirus outbreak.

  17. Performance of a one-step quantitative duplex RT-PCR for detection of rotavirus A and noroviruses GII during two periods of high viral circulation.

    PubMed

    Fumian, Tulio M; Leite, José Paulo G; Rocha, Mônica S; de Andrade, Juliana S R; Fioretti, Julia M; de Assis, Rosane M S; Assis, Matheus R S; Fialho, Alexandre M; Miagostovich, Marize P

    2016-02-01

    Rotavirus A (RVA) and noroviruses (NoV) are the major viral agents of acute gastroenteritis (AGE) worldwide. In the present study, we aimed to evaluate the performance of a one-step duplex quantitative RT-PCR (dRT-qPCR) assay, established for detection and quantification of RVA and NoV genogroup II (GII) using a single DNA standard curve (SC), as well as to investigate the association between fecal viral load and optical density (OD) values, and viruses' genotyping. The results obtained by dRT-qPCR in 530 fecal samples from AGE cases were compared with methods employed for the diagnosis of those viruses as follows: enzyme immunoassay (EIA) and polyacrylamide gel electrophoresis (PAGE) for RVA; and qualitative PCR for NoV. By using dRT-qPCR, we detected RVA and NoV in 353 (66%), increasing the positivity rate by 22.5% for RVA and 11.5% NoV, comparing the number of positive samples. RVA and NoV GII were detected in a range of 5.17 × 10(3) to 6.56 × 10(9) and 3.76 × 10(3) to 9.13 × 10(10) genome copies per gram of feces, respectively. We observed a significant direct correlation between genome copies values and optical density, using dRT-qPCR and EIA assays, respectively (Spearman ρ=0.41; p<0.0001). Viruses characterization demonstrated a predominance of NoV GII.4 Sidney 2012 variant during October 2013 to February 2014, followed by the emergence of RVA genotype G12P[8] in 2014. The established assay using a single SC provides an early feedback concerning detection and quantification, with the advantage of detecting simultaneously RVA and NoV GII, reducing time and reagent costs.

  18. Rotavirus capsid VP6 protein acts as an adjuvant in vivo for norovirus virus-like particles in a combination vaccine

    PubMed Central

    Blazevic, Vesna; Malm, Maria; Arinobu, Daisuke; Lappalainen, Suvi; Vesikari, Timo

    2016-01-01

    ABSTRACT Rotavirus (RV) and norovirus (NoV) are the 2 leading causes of acute viral gastroenteritis worldwide. We have developed a non-live NoV and RV vaccine candidate consisting of NoV virus-like particles (VLPs) and recombinant polymeric RV VP6 protein produced in baculovirus-insect cell expression system. Both components have been shown to induce strong potentially protective immune responses. As VP6 nanotubes are highly immunogenic, we investigated here a possible adjuvant effect of these structures on NoV-specific immune responses in vivo. BALB/c mice were immunized intramuscularly with a suboptimal dose (0.3 μg) of GII.4 or GI.3 VLPs either alone or in a combination with 10 μg dose of VP6 and induction of NoV-specific antibodies in sera of experimental animals were measured. Blocking assay using human saliva or synthetic histo-blood group antigens was employed to test NoV blocking antibodies. Suboptimal doses of the VLPs alone did not induce substantial anti-NoV antibodies. When co-administered with the VP6, considerable titers of not only type-specific but also cross-reactive IgG antibodies against NoV VLP genotypes not included in the vaccine composition were induced. Most importantly, NoV-specific blocking antibodies, a surrogate for neutralizing antibodies, were generated. Our results show that RV VP6 protein has an in vivo adjuvant effect on NoV-specific antibody responses and support the use of VP6 protein as a part of the NoV-RV combination vaccine, especially when addition of external adjuvants is not desirable. PMID:26467630

  19. Low Prevalence of Rotavirus and High Prevalence of Norovirus in Hospital and Community Wastewater after Introduction of Rotavirus Vaccine in Nicaragua

    PubMed Central

    Bucardo, Filemón; Lindgren, Per-Eric; Svensson, Lennart; Nordgren, Johan

    2011-01-01

    Rotavirus (RV) and norovirus (NoV) are major causes of pediatric diarrhea and are altogether associated with approximately 800,000 deaths in young children every year. In Nicaragua, national RV vaccination program using the pentavalent RV5 vaccine from Merck was implemented in October 2006. To determine whether RV vaccination decreased the overall number of RV infections, we investigated the occurrence of RV and NoV in wastewater in the city of León from July 2007 to July 2008 and compared these data with pre-vaccination data. The major finding was the low prevalence of RV compared to NoV in all sampling points (11% vs 44%, p<0.05), and that RV concentration was lower as compared to NoV. RV was observed mainly during the rainy season (July–September), and the majority of all RV detected (6/9) belonged to subgroup (SG) I. The partial VP7-gene obtained from one RV positive sample was similar (99% nt identity) to a G6 VP7-gene of bovine origin and similar to the corresponding gene of the vaccine strain (98%). Furthermore RV G-types 2 and 4 were found in the incoming wastewater. NoV strains were detected throughout the year, of which a majority (20/21) were of genotype GII.4. We conclude that the introduction of RV vaccination reduced the transmission of RV in the community in Nicaragua. However, the burden of diarrhea in the country remains high, and the high prevalence of NoVs in hospital and municipal wastewater is noteworthy. This study highlights the need for further assessment of NoV following RV vaccine introduction. PMID:22016794

  20. Stable variant-specific transcripts of the variant cell surface glycoprotein gene 1. 8 expression site in Trypanosoma brucei

    SciTech Connect

    Shea, C.; Van der Ploeg, L.H.T.

    1988-02-01

    The structure and transcriptional regulation of the 1.8 variant cell surface glycoproteins (VSG) gene expression site located on a 430-kilobase (kb) chromosome was examined in a 430-kb-chromosome-specific library. Using /sup 32/P-labeled nascent transcripts generated by nuclear run-on, the authors selected recombinant clones derived from the 430-kb chromosome which were coordinately activated with the 1.8 VSG gene. The results show that a repetitive region with a minimum size of 27 kb is coordinately activated with the 1.8 VSG gene. As with the 1.8 VSG gene, transcription is by RNA polymerases that are insensitive to the drug alpha-amanitin at concentrations up to 1 mgml. Transcription results in the generation of several stable variant-specific mRNAs. These mRNAs most likely belong to a family of repetitive expression-site-associated genes.

  1. Economic value of norovirus outbreak control measures in healthcare settings.

    PubMed

    Lee, B Y; Wettstein, Z S; McGlone, S M; Bailey, R R; Umscheid, C A; Smith, K J; Muder, R R

    2011-04-01

    Although norovirus is a significant cause of nosocomial viral gastroenteritis, the economic value of hospital outbreak containment measures following identification of a norovirus case is currently unknown. We developed computer simulation models to determine the potential cost-savings from the hospital perspective of implementing the following norovirus outbreak control interventions: (i) increased hand hygiene measures, (ii) enhanced disinfection practices, (iii) patient isolation, (iv) use of protective apparel, (v) staff exclusion policies, and (vi) ward closure. Sensitivity analyses explored the impact of varying intervention efficacy, number of initial norovirus cases, the norovirus reproductive rate (R(0)), and room, ward size, and occupancy. Implementing increased hand hygiene, using protective apparel, staff exclusion policies or increased disinfection separately or in bundles provided net cost-savings, even when the intervention was only 10% effective in preventing further norovirus transmission. Patient isolation or ward closure was cost-saving only when transmission prevention efficacy was very high (≥ 90%), and their economic value decreased as the number of beds per room and the number of empty beds per ward increased. Increased hand hygiene, using protective apparel or increased disinfection practices separately or in bundles are the most cost-saving interventions for the control and containment of a norovirus outbreak.

  2. Norovirus contamination on French marketed oysters

    PubMed Central

    Schaeffer, Julien; Le Saux, Jean-Claude; Lora, Monica; Atmar, Robert L.; Le Guyader, Françoise S.

    2014-01-01

    Contaminated shellfish have been implicated in gastroenteritis outbreaks in different countries. As no regulation has been set up yet regarding viral contamination of food, very few data are available on the prevalence of contaminated products on the market. This study presents data obtained from oysters collected on the French market in one producing area over a 16 month period of time. Noroviruses were detected in 9% of samples with a seasonal impact and influence of climatic events. Contamination levels were low and, surprisingly, oysters sampled directly from the producer were found to have less contamination than oysters from supermarkets. PMID:23973835

  3. Norovirus contamination on French marketed oysters.

    PubMed

    Schaeffer, Julien; Le Saux, Jean-Claude; Lora, Monica; Atmar, Robert L; Le Guyader, Françoise S

    2013-09-02

    Contaminated shellfish have been implicated in gastroenteritis outbreaks in different countries. As no regulation has been set up yet regarding viral contamination of food, very few data are available on the prevalence of contaminated products on the market. This study presents data obtained from oysters collected on the French market in one producing area over a 16 month period of time. Noroviruses were detected in 9% of samples with a seasonal impact and influence of climatic events. Contamination levels were low and, surprisingly, oysters sampled directly from the producer were found to have less contamination than oysters from supermarkets.

  4. Structural Basis for Norovirus Inhibition by Human Milk Oligosaccharides

    PubMed Central

    Weichert, Stefan; Koromyslova, Anna; Singh, Bishal K.; Hansman, Satoko; Jennewein, Stefan; Schroten, Horst

    2016-01-01

    Histo-blood group antigens (HBGAs) are important binding factors for norovirus infections. We show that two human milk oligosaccharides, 2′-fucosyllactose (2′FL) and 3-fucosyllactose (3FL), could block norovirus from binding to surrogate HBGA samples. We found that 2′FL and 3FL bound at the equivalent HBGA pockets on the norovirus capsid using X-ray crystallography. Our data revealed that 2′FL and 3FL structurally mimic HBGAs. These results suggest that 2′FL and 3FL might act as naturally occurring decoys in humans. PMID:26889023

  5. Characterization of ozone disinfection of murine norovirus.

    PubMed

    Lim, Mi Young; Kim, Ju-Mi; Lee, Jung Eun; Ko, GwangPyo

    2010-02-01

    Despite the importance of human noroviruses (NoVs) in public health, little information concerning the effectiveness of ozone against NoVs is available. We determined the efficacy of ozone disinfection using murine norovirus (MNV) as a surrogate of human NoV. MNV in ozone demand-free buffer was exposed to a predetermined dose of ozone at two different pHs and temperatures. The virus remaining in the solution was analyzed by plaque assay, real-time TaqMan reverse transcriptase PCR (RT-PCR) (short template), and long-template conventional RT-PCR. Under all conditions, more than 99% of the MNV was inactivated by ozone at 1 mg/liter within 2 min. Both RT-PCR assays significantly underestimated the inactivation of MNV, compared with that measured by plaque assay. Our results indicate that NoV may be more resistant to ozone than has been previously reported. Nevertheless, proper ozone disinfection practices can be used to easily control its transmission in water.

  6. [Norovirus outbreak in Majorca (Spain) associated with oyster consumption].

    PubMed

    Galmés Truyols, Antònia; Duran, Jaume Giménez; Riutort, Antonio Nicolau; Cerdá, Gabriel Arbona; Isabel, Catalina Bosch; Arbona, Margarita Portell; Berga, Joana Vanrell

    2011-01-01

    We describe investigation into an outbreak of norovirus gastroenteritis associated with oyster consumption. A survey was conducted in 346 exposed persons, 266 of whom were cases. Only 14 feces samples from patients were sent to the National Microbiology Laboratory. Oysters collected at the production site were sent to the National Food Center. The oysters met the microbiological quality standard required before sale, which did not include virus investigation. Epidemiological analysis showed an association between gastroenteritis and consumption of oysters (OR = 60.4; 95% CI: 26.2-139.3) and razor shells (OR = 3.13; 95% CI: 1.4-6.9). Microbiological analysis confirmed norovirus in affected individuals but not in the oysters that had been tested after a longer purification period than those consumed. Food with a special risk of norovirus transmission should be strictly monitored. Investigators should dispose of the necessary laboratory resources to study food-borne norovirus outbreaks.

  7. Tropical and travel-associated norovirus: current concepts

    PubMed Central

    Ballard, Sarah-Blythe; Saito, Mayuko; Mirelman, Andrew J.; Bern, Caryn; Gilman, Robert H.

    2015-01-01

    Purpose of review We highlight recent advances relevant to understanding norovirus infections in the tropics, both in populations living in developing settings and travelers to these regions. Recent findings Because of the decrease in diarrheal disease associated with the global rollout of vaccines against rotavirus, norovirus is emerging as the predominant cause of diarrhea morbidity among children in the tropics, and evidence suggests that it contributes to adult disease in endemic populations and travelers. In addition to identifying potential target populations for preventive measures, we provide an update on norovirus vaccine development and concepts related to their implementation in low-income and middle-income countries. Summary These current concepts related to norovirus-attributable disease burden, clinical significance, and economic impact can potentially be applied to tailoring efforts to prevent and mitigate the effects of this important enteropathogen. PMID:26237546

  8. Molecular Diagnostic Methods for Detection and Characterization of Human Noroviruses

    PubMed Central

    Chen, Haifeng; Hu, Yuan

    2016-01-01

    Human noroviruses are a group of viral agents that afflict people of all age groups. The viruses are now recognized as the most common causative agent of nonbacterial acute gastroenteritis and foodborne viral illness worldwide. However, they have been considered to play insignificant roles in the disease burden of acute gastroenteritis for the past decades until the recent advent of new and more sensitive molecular diagnostic methods. The availability and application of the molecular diagnostic methods have led to enhanced detection of noroviruses in clinical, food and environmental samples, significantly increasing the recognition of noroviruses as an etiologic agent of epidemic and sporadic acute gastroenteritis. This article aims to summarize recent efforts made for the development of molecular methods for the detection and characterization of human noroviruses. PMID:27335620

  9. Relative frequency of norovirus infection in children with acute gastroenteritis.

    PubMed

    Çöl, D; Biçer, S; Uğraş, M; Küçük, Ö; Giray, T; Gürol, Y; Erdağ, G Ç; Vitrinel, A; Çelik, G; Kaspar, Ç

    2015-02-01

    The aim of this study was to determine the prevalence of norovirus among children with acute gastroenteritis in 2009 and 2010. We also aimed that, to detecting the possible clinical and laboratory differences among cases in 2009 and 2010. Fecal samples were collected from children under 16 years of age who were admitted for acute gastroenteritis. Norovirus was detected using immunochromatography. For the comparison of seasonal distribution, clinical manifestations, and laboratory results between cases, we divided subjects into two groups by year. Norovirus infection was detected in 112 of the 1027 collected samples (10.9%). In three cases with norovirus, other enteric viruses like rotavirus and adenovirus are detected concurrently, and these were excluded. After the exclusion of three cases with co-infections, statistical analysis was made in 109 cases. Most of the positive cases were between 1-24 months of age (N.=75, 67%). The rate of norovirus infection peaked in winter in 2010 (P<0.05). However, the rates were not significantly different between seasons in 2009 (P>0.05). We did not detect any positive cases in late summer and autumn in 2010. Diarrhea (97.2%), vomiting (95.4%), and abdominal pain (65.1%) were most frequently encountered symptoms of patients with norovirus. Leukocytosis and neutrophilia were significantly higher in 2010 than 2009 (P<0.05). The prevalence and clinical characteristics of norovirus in our study group is similar but seasonal distribution is different between two years. Most of the cases were <24 months of age. Like rotavirus, norovirus vaccine can be developed to prevent infection.

  10. Norovirus genetic diversity and evolution: implications for antiviral therapy.

    PubMed

    Rocha-Pereira, Joana; Van Dycke, Jana; Neyts, Johan

    2016-10-01

    Human noroviruses are the leading cause of foodborne illness causing both acute and chronic gastroenteritis. In recent years, a number of vaccine candidates entered (pre-) clinical development and the first efforts to develop antiviral therapy have been made. We here discuss aspects of norovirus genetic evolution, persistence in immunocompromised patients as well as the risk and potential consequences of resistance development toward future antiviral drugs. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Environmental indicators of oyster norovirus outbreaks in coastal waters.

    PubMed

    Shamkhali Chenar, Shima; Deng, Zhiqiang

    2017-09-01

    This paper presents an artificial intelligence-based approach to identifying environmental indicators of oyster norovirus outbreaks in coastal waters. It was found that oyster norovirus outbreaks are generally linked to the extreme combination of antecedent environmental conditions characterized by low water temperature, low solar radiation, low gage height, low salinity, strong wind, and heavy precipitation. Among the six environmental indicators, the most important three indicators, including water temperature, solar radiation and gage height, are capable of explaining 77.7% of model-predicted oyster norovirus outbreaks while the extremely low temperature alone may explain 37.2% of oyster norovirus outbreaks. It is, therefore, recommended that water temperature in oyster harvesting areas be monitored in the cold season and particularly the extremely low temperature during a low gage height be used as the primary indicator of oyster norovirus outbreaks. The findings are of profound significance to reducing the public health risk of norovirus outbreaks associated with consumption of oysters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Norovirus infections in preterm infants: wide variety of clinical courses

    PubMed Central

    Armbrust, Sven; Kramer, Axel; Olbertz, Dirk; Zimmermann, Kathrin; Fusch, Christoph

    2009-01-01

    Background Norovirus is an important cause of nonbacterial acute gastroenteritis in all ages. Atypical courses are described. Clinical symptoms are diarrhea, vomiting, nausea, abdominal cramps, fever and malaise. Apart from three recent short reports we describe for the first time an outbreak of norovirus in a tertiary Neonatal Intensive Care Unit. Findings The typical symptoms of norovirus infection are in part also seen in premature born infants but with a different pattern and a huge variety of clinical courses. Vomiting is not the main symptom of norovirus infection in premature infants but distended abdomen and other symptoms such as apnea, gastric remainders or sepsis like appearance. The course in premature born patients could be explained by an immunocompromised mice model. Extensive hygienic measures were necessary to control the outbreak without closing the Neonatal Intensive Care Unit. Conclusion Norovirus infection in premature infants shows an impressive pattern of a wide variety of clinical courses. Only the consequent use of different hygienic pattern can lead to elimination of norovirus. PMID:19490612

  13. Anti-Norovirus Therapeutics: A Patent Review (2010–2015)

    PubMed Central

    Galasiti Kankanamalage, Anushka C.; Weerawarna, Pathum M.; Kim, Yunjeong; Chang, Kyeong-Ok; Groutas, William C.

    2016-01-01

    Introduction Human noroviruses are the primary causative agents of acute gastroenteritis and are a pressing public health burden worldwide. There are currently no vaccines or small molecule therapeutics available for the treatment or prophylaxis of norovirus infections. An improved understanding of norovirus biology, as well as the pathogenic mechanisms underlying the disease, has provided the impetus for a range of intense exploratory drug discovery efforts targeting viral and host factors. Areas covered An overview of norovirus inhibitors disclosed in the patent literature (2010-present) and Clinicaltrials.gov is presented. The review is further enriched and supplemented by recent literature reports. Expert opinion Seminal discoveries made in recent years, including a better understanding of the pathobiology and life cycle of norovirus, the identification and targeting of multiple viral and host factors, the advent of a replicon system and a small animal model for the preclinical evaluation of lead compounds, and the availability of high resolution X-ray crystal structures that can be utilized in structure-based drug design and lead optimization campaigns, collectively suggest that a small molecule therapeutic and prophylactic for norovirus infection is likely to emerge in the not too distant future. PMID:26881878

  14. Enteric bacteria promote human and mouse norovirus infection of B cells

    PubMed Central

    Jones, Melissa K.; Watanabe, Makiko; Zhu, Shu; Graves, Christina L.; Keyes, Lisa R.; Grau, Katrina R.; Gonzalez-Hernandez, Mariam B.; Iovine, Nicole M.; Wobus, Christiane E.; Vinjé, Jan; Tibbetts, Scott A.; Wallet, Shannon M.; Karst, Stephanie M.

    2015-01-01

    The cell tropism of human noroviruses and the development of an in vitro infection model remain elusive. Although susceptibility to individual human norovirus strains correlates with an individual’s histo-blood group antigen (HBGA) profile, the biological basis of this restriction is unknown. We demonstrate that human and mouse noroviruses infected B cells in vitro and likely in vivo. Human norovirus infection of B cells required the presence of HBGA-expressing enteric bacteria. Furthermore, mouse norovirus replication was reduced in vivo when the intestinal microbiota was depleted by means of oral antibiotic administration. Thus, we have identified B cells as a cellular target of noroviruses and enteric bacteria as a stimulatory factor for norovirus infection, leading to the development of an in vitro infection model for human noroviruses. PMID:25378626

  15. Norovirus surveillance among callers to foodborne illness complaint hotline, Minnesota, USA, 2011-2013.

    PubMed

    Saupe, Amy A; Kaehler, Dawn; Cebelinski, Elizabeth A; Nefzger, Brian; Hall, Aron J; Smith, Kirk E

    2013-08-01

    Norovirus is the leading cause of foodborne disease in the United States. During October 2011-January 2013, we conducted surveillance for norovirus infection in Minnesota among callers to a complaint-based foodborne illness hotline who reported diarrhea or vomiting. Of 241 complainants tested, 127 (52.7%) were positive for norovirus.

  16. Endemic Norovirus Infections in Children, Ho Chi Minh City, Vietnam, 2009–2010

    PubMed Central

    My, Phan Vu Tra; Thompson, Corinne; Phuc, Hoang Le; Tuyet, Pham Thi Ngoc; Vinh, Ha; Hoang, Nguyen Van Minh; Minh, Pham Van; Vinh, Nguyen Thanh; Thuy, Cao Thu; Nga, Tran Thi Thu; Hau, Nguyen Thi Thu; Campbell, James; Chinh, Nguyen Tran; Thuong, Tang Chi; Tuan, Ha Manh; Farrar, Jeremy

    2013-01-01

    We performed a case–control investigation to identify risk factors for norovirus infections among children in Vietnam. Of samples from 1,419 children who had diarrhea and 609 who were asymptomatic, 20.6% and 2.8%, respectively, were norovirus positive. Risk factors included residential crowding and symptomatic contacts, indicating person-to-person transmission of norovirus. PMID:23735160

  17. Endemic norovirus infections in children, Ho Chi Minh City, Vietnam, 2009-2010.

    PubMed

    My, Phan Vu Tra; Thompson, Corinne; Phuc, Hoang Le; Tuyet, Pham Thi Ngoc; Vinh, Ha; Hoang, Nguyen Van Minh; Minh, Pham Van; Vinh, Nguyen Thanh; Thuy, Cao Thu; Nga, Tran Thi Thu; Hau, Nguyen Thi Thu; Campbell, James; Chinh, Nguyen Tran; Thuong, Tang Chi; Tuan, Ha Manh; Farrar, Jeremy; Baker, Stephen

    2013-06-01

    We performed a case-control investigation to identify risk factors for norovirus infections among children in Vietnam. Of samples from 1,419 children who had diarrhea and 609 who were asymptomatic, 20.6% and 2.8%, respectively, were norovirus positive. Risk factors included residential crowding and symptomatic contacts, indicating person-to-person transmission of norovirus.

  18. The virucidal effects against murine norovirus and feline calicivirus F4 as surrogates for human norovirus by the different additive concentrations of ethanol-based sanitizers.

    PubMed

    Akasaka, Tempei; Shimizu-Onda, Yuko; Hayakawa, Satoshi; Ushijima, Hiroshi

    2016-03-01

    Since human norovirus is non-cultivable, murine norovirus and feline calicivirus have been used as surrogates. In this study, the virucidal effects of ethanol-based sanitizers with different concentrations of additives (malic acid/sodium malate, glycerin-fatty acid ester) against murine norovirus and feline calicivirus F4 were examined. The ethanol-based sanitizers at pH 7 showed sufficient virucidal effects, but glycerin-fatty acid ester included in ethanol-based sanitizers at pH 4 or 6 reduced the virucidal effects against murine norovirus. The ethanol-based sanitizers containing malic acid/sodium malate inactivated feline calicivirus F4 in shorter time, but there is no difference between ethanol-based sanitizers with and without glycerin-fatty acid ester. Traditionally, feline calicivirus has been used for long time as a surrogate virus for human norovirus. However, this study suggested that murine norovirus and feline calicivirus F4 had different sensitivity with the additive components of ethanol-based sanitizers. Therefore, using feline calicivirus alone as a surrogate for human norovirus may not be sufficient to evaluate the virucidal effect of sanitizers on food-borne infections caused by human norovirus. Sanitizers having virucidal effects against at least both murine norovirus and feline calicivirus may be more suitable to inactivate human norovirus.

  19. Viability and heat resistance of murine norovirus on bread.

    PubMed

    Takahashi, Michiko; Takahashi, Hajime; Kuda, Takashi; Kimura, Bon

    2016-01-04

    Contaminated bread was the cause of a large-scale outbreak of norovirus disease in Japan in 2014. Contamination of seafood and uncooked food products by norovirus has been reported several times in the past; however the outbreak resulting from the contamination of bread products was unusual. A few reports on the presence of norovirus on bread products are available; however there have been no studies on the viability and heat resistance of norovirus on breads, which were investigated in this study. ce:italic>/ce:italic> strain 1 (MNV-1), a surrogate for human norovirus, was inoculated directly on 3 types of bread, but the infectivity of MNV-1 on bread samples was almost unchanged after 5days at 20°C. MNV-1 was inoculated on white bread that was subsequently heated in a toaster for a maximum of 2min. The results showed that MNV-1 remained viable if the heating period was insufficient to inactivate. In addition, bread dough contaminated with MNV-1 was baked in the oven. Our results indicated that MNV-1 may remain viable on breads if the heating duration or temperature is insufficient. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Advances Toward a Norovirus Antiviral: From Classical Inhibitors to Lethal Mutagenesis

    PubMed Central

    Thorne, Lucy; Arias, Armando; Goodfellow, Ian

    2016-01-01

    Human noroviruses are a leading cause of gastroenteritis worldwide, yet there are no licensed antivirals. There is an urgent need for norovirus therapeutics, particularly for chronic infections in immunocompromised individuals, but also a potential need for prophylactic use in epidemics. Continued research has led to the identification of compounds that inhibit norovirus replication in vitro and, at least in some cases, are also effective in vivo against murine norovirus. Progress has included classical approaches targeting viral proteins and harnessing the antiviral action of interferon, strategies targeting essential host cell factors, and novel strategies exploiting the high mutation rate of noroviruses. PMID:26744429

  1. Advances Toward a Norovirus Antiviral: From Classical Inhibitors to Lethal Mutagenesis.

    PubMed

    Thorne, Lucy; Arias, Armando; Goodfellow, Ian

    2016-02-01

    Human noroviruses are a leading cause of gastroenteritis worldwide, yet there are no licensed antivirals. There is an urgent need for norovirus therapeutics, particularly for chronic infections in immunocompromised individuals, but also a potential need for prophylactic use in epidemics. Continued research has led to the identification of compounds that inhibit norovirus replication in vitro and, at least in some cases, are also effective in vivo against murine norovirus. Progress has included classical approaches targeting viral proteins and harnessing the antiviral action of interferon, strategies targeting essential host cell factors, and novel strategies exploiting the high mutation rate of noroviruses.

  2. Norovirus prevalence in ‘pathogen negative’ gastroenteritis in children from periurban areas in Lima, Peru

    PubMed Central

    Rivera, Fulton P.; Ochoa, Theresa J.; Ruiz, Joaquim; Medina, Anicia M.; Ecker, Lucie; Mercado, Erik; Gil, Ana I.; Huicho, Luis; Lanata, Claudio F.

    2011-01-01

    Summary Norovirus was detected in 17.4% of 224 diarrhoeal samples from children younger than 24 months of age in Lima, in whom all common pathogens had been excluded (pathogen negative). Norovirus was identified more frequently in children older than 12 months of age than in younger children (34% vs 8%, P<0.001). Among norovirus-positive samples, genogroup II was the predominant group (92%). Compared with rotavirus, norovirus episodes tended to be of shorter duration and less severe. The role of norovirus as a cause of diarrhoea and the ascertainment of its severity in developing countries needs further confirmation by future epidemiological studies. PMID:21962615

  3. Determination of the thermal inactivation kinetics of the human norovirus surrogates, murine norovirus and feline calicivirus.

    PubMed

    Bozkurt, Hayriye; D'Souza, Doris H; Davidson, P Michael

    2013-01-01

    Studies are needed to bridge existing data gaps and determine appropriate parameters for thermal inactivation methods for human noroviruses. Cultivable surrogates, such as feline calicivirus (FCV-F9) and murine norovirus (MNV-1), have been used in the absence of human norovirus infectivity assays. This study aimed to characterize the thermal inactivation kinetics of MNV-1 and FCV-F9 at 50, 56, 60, 65, and 72°C for different treatment times (0 to 60 min). Thermal inactivation was performed using the capillary tube method with titers of 4.0 × 10(7) (MNV-1) and 5.8 × 10(8) (FCV-F9) PFU/ml in triplicate experiments, followed by standard plaque assays in duplicate for each experiment. Weibull and first-order models were compared to describe survival curve kinetics. Model fitness was investigated by comparing the regression coefficients (R(2)) and the chi-square (χ(2)) and root mean square error (RMSE) values. The D-values calculated from the first-order model (50 to 72°C) were 0.15 to 34.49 min for MNV-1 and 0.11 to 20.23 min for FCV-9. Using the Weibull model, the t(D) values needed to destroy 1 log PFU of MNV-1 and FCV-F9 at the same temperatures were 0.11 to 28.26 and 0.06 to 13.86 min, respectively. In terms of thermal resistance, MNV-1 was more sensitive than FCV-F9 up to 65°C. At 72°C, FCV-F9 was slightly more susceptible to heat inactivation. Results revealed that the Weibull model was more appropriate to represent the thermal inactivation behavior of both tested surrogates. The z-values were calculated using D-values for the first-order model and the t(D) values for the Weibull model. The z-values were 9.31 and 9.19°C for MNV-1 and 9.36 and 9.31°C for FCV-F9 for the first-order and Weibull models, respectively. This study provides more precise information than previous reports on the thermal inactivation kinetics of two norovirus surrogates for use in thermal process calculations.

  4. Batch testing for noroviruses in frozen raspberries.

    PubMed

    De Keuckelaere, Ann; Li, Dan; Deliens, Bart; Stals, Ambroos; Uyttendaele, Mieke

    2015-01-02

    Berries, in particular raspberries, have been associated with multiple recalls due to norovirus contamination and were linked to a number of norovirus (NoV) outbreaks. In the present study a total of 130 samples of frozen raspberries were collected from 26 batches in four different raspberry processing companies. In two companies the samples consisted of bulk frozen raspberries serving as raw material for the production of raspberry puree (an intermediate food product in a business to business setting). In two other companies, the samples consisted of bulk individually quick frozen (IQF) raspberries serving as raw material for the production of frozen fruit mixes (as a final food product for consumer). Enumeration of Escherichia coli and coliforms was performed as well as real-time reverse transcription PCR (RT-qPCR) detection of GI and GII NoV (in 2 × 10 g). In addition, in cases where positive NoV GI or GII RT-qPCR signals were obtained, an attempt to sequence the amplicons was undertaken. Six out of 70 samples taken from the 14 batches of frozen raspberries serving raspberry puree production provided a NoV RT-qPCR signal confirmed by sequencing. Four of these six positive samples clustered in one batch whereas the other two positive samples clustered in another batch from the same company. All six positive samples showed NoV RT-qPCR signals above the limit of quantification of the RT-qPCR assay. These two positive batches of frozen raspberries can be classified as being of insufficient sanitary quality. The mean NoV level in 20 g of these raspberry samples was 4.3 log genomic copies NoV GI/20 g. The concern for public health is uncertain as NoV RT-qPCR detection is unable to discriminate between infectious and non-infectious virus particles. For the IQF raspberries, one batch out of 12 tested NoV positive, but only 1 out of the 5 samples analyzed in this batch showed a positive RT-qPCR GI NoV signal confirmed by sequencing. The RT-qPCR signal was below the

  5. Non-thermal inactivation of Noroviruses in food

    NASA Astrophysics Data System (ADS)

    Velebit, B.; Petronijević, R.; Bošković, T.

    2017-09-01

    An increased incidence of foodborne illnesses caused by Norovirus and consumer demand for fresh, convenient, and safe foods have prompted research into alternative antiviral processing technologies. Chlorine dioxide, UV treatment and thermal processing are standard antinoroviral technologies that have been employed for a while; however, they tend to be non-effective in modern processing due to residue concerns (ClO2), shadowing effects (UV) and low-energy efficiency (heat treatment). Alternative technologies have been validated such as ozone treatment, high pressure processing and pulse electric fields. Although these techniques are promising, none of them individually can deem food free of Norovirus. Further research on the effects on Norovirus in various food matrices is required. Good manufacturing practices and proper sanitation procedures remain the “gold” safety tools in food business.

  6. An outbreak of norovirus linked to oysters in Tasmania.

    PubMed

    Lodo, Kerryn L; Veitch, Mark G K; Green, Michelle L

    2014-03-31

    Norovirus is the most commonly reported virus in shellfish related gastroenteritis outbreaks. In March 2013 an investigation was conducted following the receipt of reports of gastroenteritis after the consumption of oysters at private functions in Tasmania. Cases were ascertained through general practitioners, emergency departments, media releases and self-reporting. Of the 306 cases identified in Tasmania, ten faecal specimens were collected for laboratory testing and eight were positive for norovirus (GII.g). The most common symptoms were vomiting (87%), diarrhoea (85%), myalgia (82%) and fever (56%). The implicated oysters were traced to a single lease from which they were harvested and distributed locally and interstate. Nationally 525 cases were identified from Tasmania (306), Victoria (209), New South Wales (8) and Queensland (2). This report highlights the consequences of norovirus outbreaks in shellfish, even with rapid identification, trace back and removal of the implicated product from the market.

  7. Genogroup IV and VI canine noroviruses interact with histo-blood group antigens.

    PubMed

    Caddy, Sarah; Breiman, Adrien; le Pendu, Jacques; Goodfellow, Ian

    2014-09-01

    Human noroviruses (HuNV) are a significant cause of viral gastroenteritis in humans worldwide. HuNV attaches to cell surface carbohydrate structures known as histo-blood group antigens (HBGAs) prior to internalization, and HBGA polymorphism among human populations is closely linked to susceptibility to HuNV. Noroviruses are divided into 6 genogroups, with human strains grouped into genogroups I (GI), II, and IV. Canine norovirus (CNV) is a recently discovered pathogen in dogs, with strains classified into genogroups IV and VI. Whereas it is known that GI to GIII noroviruses bind to HBGAs and GV noroviruses recognize terminal sialic acid residues, the attachment factors for GIV and GVI noroviruses have not been reported. This study sought to determine the carbohydrate binding specificity of CNV and to compare it to the binding specificities of noroviruses from other genogroups. A panel of synthetic oligosaccharides were used to assess the binding specificity of CNV virus-like particles (VLPs) and identified α1,2-fucose as a key attachment factor. CNV VLP binding to canine saliva and tissue samples using enzyme-linked immunosorbent assays (ELISAs) and immunohistochemistry confirmed that α1,2-fucose-containing H and A antigens of the HBGA family were recognized by CNV. Phenotyping studies demonstrated expression of these antigens in a population of dogs. The virus-ligand interaction was further characterized using blockade studies, cell lines expressing HBGAs, and enzymatic removal of candidate carbohydrates from tissue sections. Recognition of HBGAs by CNV provides new insights into the evolution of noroviruses and raises concerns regarding the potential for zoonotic transmission of CNV to humans. Infections with human norovirus cause acute gastroenteritis in millions of people each year worldwide. Noroviruses can also affect nonhuman species and are divided into 6 different groups based on their capsid sequences. Human noroviruses in genogroups I and II interact

  8. Genogroup IV and VI Canine Noroviruses Interact with Histo-Blood Group Antigens

    PubMed Central

    Breiman, Adrien; le Pendu, Jacques

    2014-01-01

    ABSTRACT Human noroviruses (HuNV) are a significant cause of viral gastroenteritis in humans worldwide. HuNV attaches to cell surface carbohydrate structures known as histo-blood group antigens (HBGAs) prior to internalization, and HBGA polymorphism among human populations is closely linked to susceptibility to HuNV. Noroviruses are divided into 6 genogroups, with human strains grouped into genogroups I (GI), II, and IV. Canine norovirus (CNV) is a recently discovered pathogen in dogs, with strains classified into genogroups IV and VI. Whereas it is known that GI to GIII noroviruses bind to HBGAs and GV noroviruses recognize terminal sialic acid residues, the attachment factors for GIV and GVI noroviruses have not been reported. This study sought to determine the carbohydrate binding specificity of CNV and to compare it to the binding specificities of noroviruses from other genogroups. A panel of synthetic oligosaccharides were used to assess the binding specificity of CNV virus-like particles (VLPs) and identified α1,2-fucose as a key attachment factor. CNV VLP binding to canine saliva and tissue samples using enzyme-linked immunosorbent assays (ELISAs) and immunohistochemistry confirmed that α1,2-fucose-containing H and A antigens of the HBGA family were recognized by CNV. Phenotyping studies demonstrated expression of these antigens in a population of dogs. The virus-ligand interaction was further characterized using blockade studies, cell lines expressing HBGAs, and enzymatic removal of candidate carbohydrates from tissue sections. Recognition of HBGAs by CNV provides new insights into the evolution of noroviruses and raises concerns regarding the potential for zoonotic transmission of CNV to humans. IMPORTANCE Infections with human norovirus cause acute gastroenteritis in millions of people each year worldwide. Noroviruses can also affect nonhuman species and are divided into 6 different groups based on their capsid sequences. Human noroviruses in genogroups

  9. Diagnosing norovirus-associated infectious intestinal disease using viral load.

    PubMed

    Phillips, Gemma; Lopman, Ben; Tam, Clarence C; Iturriza-Gomara, Miren; Brown, David; Gray, Jim

    2009-05-14

    Reverse transcription-polymerase chain reaction (RT-PCR) is the main method for laboratory diagnosis of norovirus-associated infectious intestinal disease (IID). However, up to 16% of healthy individuals in the community, with no recent history of IID, may be RT-PCR positive; so it is unclear whether norovirus is actually the cause of illness in an IID case when they are RT-PCR positive. It is important to identify the pathogen causing illness in sporadic IID cases, for clinical management and for community based incidence studies. The aim of this study was to investigate how faecal viral load can be used to determine when norovirus is the most likely cause of illness in an IID case. Real-time RT-PCR was used to determine the viral load in faecal specimens collected from 589 IID cases and 159 healthy controls, who were infected with genogroup II noroviruses. Cycle threshold (Ct) values from the real-time RT-PCR were used as a proxy measure of viral load. Receiver-operating characteristic (ROC) analysis was used to identify a cut-off in viral load for attributing illness to norovirus in IID cases. One hundred and sixty-nine IID cases and 159 controls met the inclusion criteria for the ROC analysis. The optimal Ct value cut-off for attributing IID to norovirus was 31. The same cut-off was selected when using healthy controls, or IID cases who were positive by culture for bacterial pathogens, as the reference negative group. This alternative reference negative group can be identified amongst specimens routinely received in clinical virology laboratories. We demonstrated that ROC analysis can be used to select a cut-off for a norovirus real time RT-PCR assay, to aid clinical interpretation and diagnose when norovirus is the cause of IID. Specimens routinely received for diagnosis in clinical virology laboratories can be used to select an appropriate cut-off. Individual laboratories can use this method to define in-house cut-offs for their assays, to provide the best

  10. Duration of immunity to norovirus gastroenteritis.

    PubMed

    Simmons, Kirsten; Gambhir, Manoj; Leon, Juan; Lopman, Ben

    2013-08-01

    The duration of immunity to norovirus (NoV) gastroenteritis has been believed to be from 6 months to 2 years. However, several observations are inconsistent with this short period. To gain better estimates of the duration of immunity to NoV, we developed a mathematical model of community NoV transmission. The model was parameterized from the literature and also fit to age-specific incidence data from England and Wales by using maximum likelihood. We developed several scenarios to determine the effect of unknowns regarding transmission and immunity on estimates of the duration of immunity. In the various models, duration of immunity to NoV gastroenteritis was estimated at 4.1 (95% CI 3.2-5.1) to 8.7 (95% CI 6.8-11.3) years. Moreover, we calculated that children (<5 years) are much more infectious than older children and adults. If a vaccine can achieve protection for duration of natural immunity indicated by our results, its potential health and economic benefits could be substantial.

  11. Eliminating Murine Norovirus by Cross-Fostering

    PubMed Central

    Buxbaum, Laurence U.; DeRitis, Pierina C.; Chu, Niansheng; Conti, Pierre A.

    2011-01-01

    Murine norovirus (MNV) is a newly discovered and extremely prevalent pathogen of laboratory mouse colonies. MNV causes severe disease in some immunocompromised mouse strains and can cause persistent infections even in immunocompetent mice. Despite the fact that immunocompetent mice are generally asymptomatic, the possibility that MNV infection might alter immune responses makes its eradication a potentially useful goal for many facilities. Initial attempts by others to use a strategy of testing and culling were unsuccessful, whereas complete depopulation and facility decontamination was successful. However, these measures may be impractical, and finding less drastic approaches seemed prudent. Based on a report that cross-fostering of pups from MNV-positive mothers to MNV-negative ones could be successful in experimental MNV infection, we undertook a comprehensive fostering program using Swiss Webster mothers, careful sanitary measures, and fecal PCR testing to eradicate the virus from a mouse colony recently infected with MNV. We successfully decontaminated 17 of 18 (94%) litters and managed to prevent spread when a new MNV-infected mouse strain entered quarantine at our facility. These results suggest that cross-fostering, when performed in a setting of excellent sanitary procedures, may be practical for the large number of mouse facilities in which MNV is endemic. PMID:21838978

  12. Inactivation of a Human Norovirus Surrogate, Human Norovirus Virus-Like Particles, and Vesicular Stomatitis Virus by Gamma Irradiation ▿

    PubMed Central

    Feng, Kurtis; Divers, Erin; Ma, Yuanmei; Li, Jianrong

    2011-01-01

    Gamma irradiation is a nonthermal processing technology that has been used for the preservation of a variety of food products. This technology has been shown to effectively inactivate bacterial pathogens. Currently, the FDA has approved doses of up to 4.0 kGy to control food-borne pathogens in fresh iceberg lettuce and spinach. However, whether this dose range effectively inactivates food-borne viruses is less understood. We have performed a systematic study on the inactivation of a human norovirus surrogate (murine norovirus 1 [MNV-1]), human norovirus virus-like particles (VLPs), and vesicular stomatitis virus (VSV) by gamma irradiation. We demonstrated that MNV-1 and human norovirus VLPs were resistant to gamma irradiation. For MNV-1, only a 1.7- to 2.4-log virus reduction in fresh produce at the dose of 5.6 kGy was observed. However, VSV was more susceptible to gamma irradiation, and a 3.3-log virus reduction at a dose of 5.6 kGy in Dulbecco's modified Eagle medium (DMEM) was achieved. We further demonstrated that gamma irradiation disrupted virion structure and degraded viral proteins and genomic RNA, which resulted in virus inactivation. Using human norovirus VLPs as a model, we provide the first evidence that the capsid of human norovirus has stability similar to that of MNV-1 after exposure to gamma irradiation. Overall, our results suggest that viruses are much more resistant to irradiation than bacterial pathogens. Although gamma irradiation used to eliminate the virus contaminants in fresh produce by the FDA-approved irradiation dose limits seems impractical, this technology may be practical to inactivate viruses for other purposes, such as sterilization of medical equipment. PMID:21441330

  13. Norovirus infections in young children in Lusaka Province, Zambia: clinical characteristics and molecular epidemiology.

    PubMed

    Howard, Leigh M; Mwape, Innocent; Siwingwa, Mpanji; Simuyandi, Michelo; Guffey, M Brad; Stringer, Jeffrey S A; Chi, Benjamin H; Edwards, Kathryn M; Chilengi, Roma

    2017-01-23

    The burden, clinical features, and molecular epidemiology of norovirus infection in young children in southern Africa are not well defined. Using data from a health facility-based surveillance study of children <5 years in Lusaka Province, Zambia presenting with diarrhea, we assessed the burden of norovirus infection. A convenience sample of 454 stool specimens was tested for norovirus using reverse-transcriptase polymerase chain reaction (RT-PCR). RT-PCR positive samples underwent additional nucleotide sequencing for genogroup and genotype identification. Clinical features and severity of diarrheal illnesses were compared between norovirus-positive and -negative subjects using Chi-squared and t-tests. Norovirus was detected in 52/454 (11.5%) specimens tested. Abdominal pain, fever, and vomiting were the most common presenting features in norovirus-associated illnesses. However, there were no significant differences in the clinical features of norovirus-positive compared to norovirus-negative illnesses. Of 43 isolates that were available for sequencing, 31 (72.1%) were genogroup II (GII) and 12 (27.9%) were genogroup I (GI). The distribution of genotypes was diverse. Noroviruses were detected in approximately 10% of young children with diarrhea in the Lusaka Province of Zambia, with GII representing the majority of infections. These findings support the role of norovirus in symptomatic diarrhea disease in Africa. Further studies are needed to confirm these observations and to evaluate prevention strategies.

  14. A survey of Australian oysters for the presence of human noroviruses.

    PubMed

    Brake, Felicity; Ross, Tom; Holds, Geoffrey; Kiermeier, Andreas; McLeod, Catherine

    2014-12-01

    Impending international policies for norovirus in oysters and the lack of Australian data suggested there was a need to undertake a national survey of norovirus in oysters. Two geographically distinct oyster-growing areas from each of three Australian states were sampled on 4 occasions during 2010 and 2011. The sites selected were considered by state shellfish authorities to be the most compromised with respect to the potential for human faecal contamination as identified by shoreline surveys. The oysters were tested for norovirus GI, GII and Escherichia coli. Norovirus GII was detected in two of 120 (1.7%) samples and norovirus GI was not detected. One of the norovirus positive samples was cloned and sequenced as GII.3. Five of 120 (4.2%) samples were found to have more than the guidance concentration of 230 E. coli per 100 g of shellfish but these samples did not contain detectable concentrations of norovirus. The apparently low prevalence of norovirus in oysters from Australian growing areas supports epidemiological data that suggests norovirus contamination of Australian oysters is rare. The results from this study emphasise the need for future norovirus control measures for shellfish to be commensurate with the risk associated with the growing area.

  15. Variable high pressure processing sensitivities for GII human noroviruses

    USDA-ARS?s Scientific Manuscript database

    Human norovirus (HuNoV) is the leading cause of foodborne diseases worldwide. High pressure processing (HPP) is one of the most promising non-thermal technologies for decontamination of viral pathogens in foods. However, the survival of HuNoVs by HPP is poorly understood because these viruses cann...

  16. Inactivation of a Norovirus by High-Pressure Processing▿

    PubMed Central

    Kingsley, David H.; Holliman, Daniel R.; Calci, Kevin R.; Chen, Haiqiang; Flick, George J.

    2007-01-01

    Murine norovirus (strain MNV-1), a propagable norovirus, was evaluated for susceptibility to high-pressure processing. Experiments with virus stocks in Dulbecco's modified Eagle medium demonstrated that at room temperature (20°C) the virus was inactivated over a pressure range of 350 to 450 MPa, with a 5-min, 450-MPa treatment being sufficient to inactivate 6.85 log10 PFU of MNV-1. The inactivation of MNV-1 was enhanced when pressure was applied at an initial temperature of 5°C; a 5-min pressure treatment of 350 MPa at 30°C inactivated 1.15 log10 PFU of virus, while the same treatment at 5°C resulted in a reduction of 5.56 log10 PFU. Evaluation of virus inactivation as a function of treatment times ranging from 0 to 150 s and 0 to 900 s at 5°C and 20°C, respectively, indicated that a decreasing rate of inactivation with time was consistent with Weibull or log-logistic inactivation kinetics. The inactivation of MNV-1 directly within oyster tissues was demonstrated; a 5-min, 400-MPa treatment at 5°C was sufficient to inactivate 4.05 log10 PFU. This work is the first demonstration that norovirus can be inactivated by high pressure and suggests good prospects for inactivation of nonpropagable human norovirus strains in foods. PMID:17142353

  17. Serum Immunoglobulin A Cross-Strain Blockade of Human Noroviruses

    PubMed Central

    Lindesmith, Lisa C.; Beltramello, Martina; Swanstrom, Jesica; Jones, Taylor A.; Corti, Davide; Lanzavecchia, Antonio; Baric, Ralph S.

    2015-01-01

    Background. Human noroviruses are the leading cause of acute viral gastroenteritis, justifying vaccine development despite a limited understanding of strain immunity. After genogroup I (GI).1 norovirus infection and immunization, blockade antibody titers to multiple virus-like particles (VLPs) increase, suggesting that GI cross-protection may occur. Methods. Immunoglobulin (Ig)A was purified from sera collected from GI.1-infected participants, and potential neutralization activity was measured using a surrogate neutralization assay based on antibody blockade of ligand binding. Human and mouse monoclonal antibodies (mAbs) were produced to multiple GI VLPs to characterize GI epitopes. Results. Immunoglobulin A purified from day 14 post-GI.1 challenge sera blocked binding of GI.1, GI.3, and GI.4 to carbohydrate ligands. In some subjects, purified IgA preferentially blocked binding of other GI VLPs compared with GI.1, supporting observations that the immune response to GI.1 infection may be influenced by pre-exposure history. For other subjects, IgA equivalently blocked multiple GI VLPs. Only strain-specific mAbs recognized blockade epitopes, whereas strain cross-reactive mAbs recognized nonblockade epitopes. Conclusions. These studies are the first to describe a functional role for serum IgA in norovirus immunity and the first to characterize human monoclonal antibodies to GI strains, expanding our understanding of norovirus immunobiology. PMID:26180833

  18. Norovirus in Bottled Water Associated with Gastroenteritis Outbreak, Spain, 2016.

    PubMed

    Blanco, Albert; Guix, Susana; Fuster, Noemí; Fuentes, Cristina; Bartolomé, Rosa; Cornejo, Thais; Pintó, Rosa Maria; Bosch, Albert

    2017-09-01

    In April 2016, an outbreak of gastrointestinal illness (4,136 cases) occurred in Catalonia, Spain. We detected high levels of norovirus genotypes I and II in office water coolers associated with the outbreak. Infectious viral titer estimates were 33-49 genome copies/L for genotype I and 327-660 genome copies/L for genotype II.

  19. Low-density microarray technologies for rapid human norovirus genotyping

    USDA-ARS?s Scientific Manuscript database

    Human noroviruses cause up to 21 million cases of foodborne disease in the United States annually and are the most common cause of acute gastroenteritis in industrialized countries. To reduce the burden of foodborne disease associated with viruses, the use of low density DNA microarrays in conjuncti...

  20. Inactivation of Tulane virus, a novel surrogate for human norovirus

    USDA-ARS?s Scientific Manuscript database

    Human noroviruses (HuNoVs) are the major cause of non-bacterial epidemics of gastroenteritis. Due to the inability to cultivate HuNoVs and the lack of an efficient small animal model, surrogates are used to study HuNoV biology. Two such surrogates, the feline calicivirus (FCV) and the murine norovir...

  1. Epidemiology of foodborne Norovirus outbreak in Incheon, Korea.

    PubMed

    Yu, Jun-Hwan; Kim, Na-Yeon; Koh, Yeon-Ja; Lee, Hun-Jae

    2010-08-01

    On June 14, 2008, an outbreak of gastroenteritis occurred among elementary school students in Incheon. We conducted an investigation to identify the source and described the extent of the outbreak. We performed a retrospective cohort study among students, teachers and food handlers exposed to canteen food in the elementary school. Using self-administered questionnaires we collected information on symptoms, days of canteen food eaten, food items consumed. Stool samples were collected from 131 symptomatic people and 11 food handlers. The catering kitchen was inspected and food samples were taken. Of the 1,560 people who ate canteen food, 117 were symptomatic cases, and the attack rate was 7.5%. Consumption of cucumber-crown daisy salad (RR=2.71), fresh cabbage mix (RR=2.23), dried radish salad (RR=3.04) and young radish kimchi (RR=2.52) were associated with illness. Sixty-four (45%) of the 142 stool specimens were positive for Norovirus. Norovirus was detected in 2 food handlers. Interviews with kitchen staff indicated the likelihood of contamination from an infected food handler to the dried radish salad during food processing. The excretion of Norovirus from asymptomatic food handlers may be an infection source of Norovirus outbreaks.

  2. Waterborne norovirus outbreak during a summer excursion in Northern Italy.

    PubMed

    Di Bartolo, Ilaria; Pavoni, Enrico; Tofani, Silvia; Consoli, Marta; Galuppini, Elisa; Losio, Marina Nadia; Ruggeri, Franco Maria; Varisco, Giorgio

    2015-01-01

    In September 2011, an acute gastroenteritis outbreak affected 33 children in Northern Italy. Patients had drunk river water during an excursion. Identical GI.4 norovirus genomes were detected from one patient's stools and from the river water. Improper discharge of human sewage into the river may have caused this waterborne outbreak.

  3. Epidemiology of foodborne norovirus outbreaks, United States, 2001-2008.

    PubMed

    Hall, Aron J; Eisenbart, Valerie G; Etingüe, Amy Lehman; Gould, L Hannah; Lopman, Ben A; Parashar, Umesh D

    2012-10-01

    Noroviruses are the leading cause of foodborne illness in the United States. To better guide interventions, we analyzed 2,922 foodborne disease outbreaks for which norovirus was the suspected or confirmed cause, which had been reported to the Foodborne Disease Outbreak Surveillance System of the Centers for Disease Control and Prevention during 2001-2008. On average, 365 foodborne norovirus outbreaks were reported annually, resulting in an estimated 10,324 illnesses, 1,247 health care provider visits, 156 hospitalizations, and 1 death. In 364 outbreaks attributed to a single commodity, leafy vegetables (33%), fruits/nuts (16%), and mollusks (13%) were implicated most commonly. Infected food handlers were the source of 53% of outbreaks and may have contributed to 82% of outbreaks. Most foods were likely contaminated during preparation and service, except for mollusks, and occasionally, produce was contaminated during production and processing. Interventions to reduce the frequency of foodborne norovirus outbreaks should focus on food workers and production of produce and shellfish.

  4. Low-Density microarray technologies for rapid human norovirus genotyping

    USDA-ARS?s Scientific Manuscript database

    Human noroviruses (HuNoV) are the most common cause of food borne disease and viruses are likely responsible for a large proportion of foodborne diseases of unknown etiology. Recent advancements in molecular biology, bioinformatics, epidemiology, and risk analysis have aided the study of these agent...

  5. Evidence-Based interventions of Norovirus outbreaks in China.

    PubMed

    Chen, Tianmu; Gu, Haogao; Leung, Ross Ka-Kit; Liu, Ruchun; Chen, Qiuping; Wu, Ying; Li, Yaman

    2016-10-12

    In resource-limited settings where laboratory capacity is limited and response strategy is non-specific, delayed or inappropriate intervention against outbreaks of Norovirus (NoV) are common. Here we report interventions of two norovirus outbreaks, which highlight the importance of evidence-based modeling and assessment to identify infection sources and formulate effective response strategies. Spatiotemporal scanning, mathematical and random walk modeling predicted the modes of transmission in the two incidents, which were supported by laboratory results and intervention outcomes. Simulation results indicated that contaminated water was 14 to 500 fold more infectious than infected individuals. Asymptomatic individuals were not effective transmitters. School closure for up to a week still could not contain the outbreak unless the duration was extended to 10 or more days. The total attack rates (TARs) for waterborne NoV outbreaks reported in China (n = 3, median = 4.37) were significantly (p < 0.05) lower than worldwide (n = 14, median = 41.34). The low TARs are likely due to the high number of the affected population. We found that school closure alone could not contain Norovirus outbreaks. Overlooked personal hygiene may serve as a hotbed for infectious disease transmission. Our results reveal that evidence-based investigations can facilitate timely interventions of Norovirus transmission.

  6. Cell Culture Assay for Human Noroviruses [response

    SciTech Connect

    Straub, Tim M.; Honer Zu Bentrup, Kerstin; Orosz Coghlan, Patricia; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza A.; Nickerson, Cheryl A.

    2007-07-01

    We appreciate the comments provided by Leung et al., in response to our recently published article “In Vitro Cell Culture Infectivity Assay for Human Noroviruses” by Straub et al. (1). The specific aim of our project was to develop an in vitro cell culture infectivity assay for human noroviruses (hNoV) to enhance risk assessments when they are detected in water supplies. Reverse transcription (RT) qualitative or quantitative PCR are the primary assays for waterborne NoV monitoring. However, these assays cannot distinguish between infectious vs. non-infectious virions. When hNoV is detected in water supplies, information provided by our infectivity assay will significantly improve risk assessment models and protect human health, regardless of whether we are propagating NoV. Indeed, in vitro cell culture infectivity assays for the waterborne pathogen Cryptosporidium parvum that supplement approved fluorescent microscopy assays, do not result in amplification of the environmentally resistant hard-walled oocysts (2). However, identification of life cycle stages in cell culture provides evidence of infectious oocysts in a water supply. Nonetheless, Leung et al.’s assertion regarding the suitability of our method for the in vitro propagation of high titers of NoV is valid for the medical research community. In this case, well-characterized challenge pools of virus would be useful for developing and testing diagnostics, therapeutics, and vaccines. As further validation of our published findings, we have now optimized RT quantitative PCR to assess the level of viral production in cell culture, where we are indeed finding significant increases in viral titer. The magnitude and time course of these increases is dependent on both virus strain and multiplicity of infection. We are currently preparing a manuscript that will discuss these findings in greater detail, and the implications this may have for creating viral challenge pools

  7. Epidemiology of Rotavirus-Norovirus Co-Infection and Determination of Norovirus Genogrouping among Children with Acute Gastroenteritis in Tehran, Iran

    PubMed Central

    Nasab, Seyed Dawood Mousavi; Sabahi, Farzaneh; Makvandi, Manoochehr; Samiee, Siamak Mirab; Nadji, Seyed Alireza; Ravanshad, Mehrdad

    2016-01-01

    Background: Enteric viruses, particularly human rotavirus and norovirus, have been shown to replace bacteria and parasites, as the most common pathogens responsible for acute diarrhea. However, there are still few epidemiological data on the simultaneous occurrence of these viruses in Iran. In this regard, the aim of this study was to assess the useful epidemiological data on the gastroenteritis associated with rotavirus-norovirus mixed infection and to examine the prevalence of norovirus genogrouping among children aged less than five years old in Iran. Methods: A total of 170 stool samples were collected from children under five years of age with the clinical signs and symptoms of acute gastroenteritis, from May 2013 to May 2014. For the detection of both rotavirus and norovirus, total RNA was extracted from all samples, followed by reverse transcription polymerase chain reaction (RT-PCR). For both detected rotaviruses and noroviruses, genogrouping was performed. Results: Of 170 samples, 49 (28.8%) and 15 (8.8%) samples were found to be positive for rotavirus and norovirus infections by RT-PCR. Interestingly, 6 (3.5%) patients were positive for both infections. Among the 15 norovirus-positive patients, 13 (86.6%) and 2 (13.3%) belonged to genogroups GII and GI. Conclusion: The norovirus genogroup GII and rotavirus lead to the serious infections in children with acute gastroenteritis. However, more well-designed studies are needed to further elucidate the role of other enteric viruses in acute gastroenteritis PMID:27137790

  8. Comparative Virucidal Efficacy of Seven Disinfectants Against Murine Norovirus and Feline Calicivirus, Surrogates of Human Norovirus.

    PubMed

    Zonta, William; Mauroy, Axel; Farnir, Frederic; Thiry, Etienne

    2016-03-01

    Human noroviruses (HuNoV) are the leading cause of acute non-bacterial gastroenteritis in humans and can be transmitted either by person-to-person contact or by consumption of contaminated food. A knowledge of an efficient disinfection for both hands and food-contact surfaces is helpful for the food sector and provides precious information for public health. The aim of this study was to evaluate the effect of seven disinfectants belonging to different groups of biocides (alcohol, halogen, oxidizing agents, quaternary ammonium compounds, aldehyde and biguanide) on infectious viral titre and on genomic copy number. Due to the absence of a cell culture system for HuNoV, two HuNoV surrogates, such as murine norovirus and feline calicivirus, were used and the tests were performed in suspension, on gloves and on stainless steel discs. When, as criteria of efficacy, a log reduction >3 of the infectious viral titre on both surrogates and in the three tests is used, the most efficacious disinfectants in this study appear to be biocidal products B, C and D, representing the halogens, the oxidizing agents group and a mix of QAC, alcohol and aldehyde, respectively. In addition, these three disinfectants also elicited a significant effect on genomic copy number for both surrogate viruses and in all three tests. The results of this study demonstrate that a halogen compound, oxidizing agents and a mix of QAC, alcohol and aldehyde are advisable for HuNoV disinfection of either potentially contaminated surfaces or materials in contact with foodstuffs.

  9. Outbreak management and implications of a nosocomial norovirus outbreak.

    PubMed

    Johnston, Cecilia P; Qiu, Haoming; Ticehurst, John R; Dickson, Conan; Rosenbaum, Patricia; Lawson, Patricia; Stokes, Amy B; Lowenstein, Charles J; Kaminsky, Michael; Cosgrove, Sara E; Green, Kim Y; Perl, Trish M

    2007-09-01

    Noroviruses are enterically transmitted and are a frequent cause of gastroenteritis, affecting 23 million people annually in the United States. We describe a norovirus outbreak and its control in a tertiary care hospital during February-May 2004. Patients and health care workers met the case definition if they had new onset of vomiting and/or diarrhea during the outbreak period. Selected stool samples were tested for norovirus RNA. We also determined outbreak costs, including the estimated lost revenue associated with unit closures, sick leave, and cleaning expenses. We identified 355 cases that affected 90 patients and 265 health care workers and that were clustered in the coronary care unit and psychiatry units. Attack rates were 5.3% (7 of 133) for patients and 29.9% (29 of 97) for health care workers in the coronary care unit and 16.7% (39 of 233) for patients and 38.0% (76 of 200) for health care workers in the psychiatry units. Thirteen affected health care workers (4.9%) required emergency department visits or hospitalization. Detected noroviruses had 98%-99% sequence identity with representatives of a new genogroup II.4 variant that emerged during 2002-2004 in the United States (e.g., Farmington Hills and other strains) and Europe. Aggressive infection-control measures, including closure of units and thorough disinfection using sodium hypochlorite, were required to terminate the outbreak. Costs associated with this outbreak were estimated to be $657,644. The significant disruption of patient care and cost of this single nosocomial outbreak support aggressive efforts to prevent transmission of noroviruses in health care settings.

  10. Acute gastroenteritis outbreak caused by a GII.6 norovirus

    PubMed Central

    Luo, Ling-Fei; Qiao, Kun; Wang, Xiao-Guang; Ding, Ke-Ying; Su, Hua-Ling; Li, Cui-Zhen; Yan, Hong-Jing

    2015-01-01

    AIM: To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6 (GII.6) strain norovirus in Shanghai, China. METHODS: Noroviruses are responsible for approximately half of all reported gastroenteritis outbreaks in many countries. Genogroup 2 genotype 4 strains are the most prevalent. Rare outbreaks caused by GII.6 strains have been reported. An acute gastroenteritis outbreak occurred in an elementary school in Shanghai in December of 2013. Field and molecular epidemiologic investigations were conducted. RESULTS: The outbreak was limited to one class in an elementary school located in southwest Shanghai. The age of the students ranged from 9 to 10 years. The first case emerged on December 10, 2013, and the last case emerged on December 14, 2013. The cases peaked on December 11, 2013, with 21 new cases. Of 45 students in the class, 32 were affected. The main symptom was gastroenteritis, and 15.6% (5/32) of the cases exhibited a fever. A field epidemiologic investigation showed the pathogen may have been transmitted to the elementary school from employees in a delicatessen via the first case student, who had eaten food from the delicatessen one day before the gastroenteritis episodes began. A molecular epidemiologic investigation identified the cause of the gastroenteritis as norovirus strain GII.6; the viral sequence of the student cases showed 100% homology with that of the shop employees. Genetic relatedness analyses showed that the new viral strain is closely related to previously reported GII.6 sequences, especially to a strain reported in Japan. CONCLUSION: This is the first report to show that norovirus strain GII.6 can cause a gastroenteritis outbreak. Thus, the prevalence of GII.6 noroviruses requires attention. PMID:25954103

  11. High pressure inactivation of human norovirus-like particles: evidence that the capsid of human norovirus is highly pressure resistant

    USDA-ARS?s Scientific Manuscript database

    High pressure processing (HPP) is a promising non-thermal technology to inactivate foodborne viruses. However, the effectiveness of HPP on inactivating human norovirus (HuNoV), the leading cause of acute gastroenteritis, is unknown because it cannot be propagated in cell culture. Therefore, developi...

  12. Human Norovirus Detection and Production, Quantification, and Storage of Virus-Like Particles

    PubMed Central

    Debbink, Kari; Costantini, Veronica; Swanstrom, Jesica; Agnihothram, Sudhakar; Vinjé, Jan; Baric, Ralph

    2014-01-01

    Human noroviruses constitute a significant worldwide disease burden. Each year noroviruses cause over 267 million infections, deaths in over 200,000 children under the age of five, and over 50% of U.S. food borne illness. Due to the absence of a tissue culture model or small animal model to study human norovirus, virus-like particles (VLPs) and ELISA-based biological assays have been used to answer questions about norovirus evolution and immunity as well provide a potential vaccine platform. This chapter outlines the protocols on norovirus detection in stool and norovirus VLP design, production, purification, and storage using a Venezuelan equine encephalitis virus (VEE)-based VRP expression system. PMID:24510290

  13. Multiple consecutive norovirus infections in the first 2 years of life.

    PubMed

    Blazevic, Vesna; Malm, Maria; Salminen, Marjo; Oikarinen, Sami; Hyöty, Heikki; Veijola, Riitta; Vesikari, Timo

    2015-12-01

    Studies investigating the magnitude and breath of protective immune responses after primary and subsequent norovirus infections in pediatric populations are limited. We investigated incidence of norovirus infections and serological responses in a child from longitudinal stool and serum samples collected from birth to 2 years of age. Four consecutive infections with distinct genotypes of norovirus were detected. Serum antibodies were genotype-specific offering no protection to reinfection with heterologous virus. This study describes norovirus-specific serological responses in a child with four consecutive norovirus infection during the first 2 years of life. The response is type-specific and does not protect from a subsequent infection with a heterologous virus. • Correlates of protection to norovirus infection and disease are not yet determined, and most of the presently available data concern adult population. • This manuscript describes serological immune responses after primary and subsequent infections in a child during the first 2 years of life.

  14. Discrepancies between Antigen and Polymerase Chain Reaction Tests for the Detection of Rotavirus and Norovirus.

    PubMed

    Kim, Hyun Soo; Kim, Jae-Seok

    2016-05-01

    We compared the results of an antigen test (ELISA) with those of polymerase chain reaction (PCR) for the detection of rotavirus and norovirus in stool specimens. Rotavirus and norovirus antigen-positive stool specimens were collected, and rotavirus and norovirus PCRs were performed on these specimens. Of the 325 rotavirus antigen-positive specimens, 200 were positive for both assays and 125 were PCR negative. Of 286 norovirus antigen-positive specimens, 51 were PCR negative. Comparison of the lower limit of detection showed that rotavirus PCR was 16 times more sensitive and norovirus PCR was over 4,000 times more sensitive than the ELISA. Discrepant results between ELISA and PCR were common, and the possibility of false-positive and false-negative results should be considered with rotavirus and norovirus assays.

  15. Chronic norovirus infection in a transplant patient successfully treated with enterally administered immune globulin.

    PubMed

    Chagla, Zain; Quirt, Jaclyn; Woodward, Kevin; Neary, John; Rutherford, Candace

    2013-09-01

    Norovirus infection causes a significant burden of morbidity and (in the developing world) mortality. In immunocompromised hosts, norovirus infection can become chronic, with devastating consequences. Unfortunately, therapeutic options for chronic disease are unproven, and treatment is largely supportive. We report a case of norovirus infection causing debilitating chronic gastroenteritis in a transplant patient that responded to a short course of enterally administered human immune globulin.

  16. Incidence of Norovirus-Associated Diarrhea, Shanghai, China, 2012–2013

    PubMed Central

    Yu, Jianxing; Ye, Chuchu; Lai, Shengjie; Zhu, Weiping; Zhang, Zike; Geng, Qibin; Xue, Caoyi; Yang, Weizhong; Wu, Shuyu; Hall, Aron J.

    2017-01-01

    We conducted sentinel-based surveillance for norovirus in the Pudong area of Shanghai, China, during 2012–2013, by analyzing 5,324 community surveys, 408,024 medical records, and 771 laboratory-confirmed norovirus infections among 3,877 diarrhea cases. Our analysis indicated an outpatient incidence of 1.5/100 person-years and a community incidence of 8.9/100 person-years for norovirus-associated diarrhea. PMID:28098539

  17. Oxadiazole-Based Cell Permeable Macrocyclic Transition State Inhibitors of Norovirus 3CL Protease.

    PubMed

    Damalanka, Vishnu C; Kim, Yunjeong; Alliston, Kevin R; Weerawarna, Pathum M; Galasiti Kankanamalage, Anushka C; Lushington, Gerald H; Mehzabeen, Nurjahan; Battaile, Kevin P; Lovell, Scott; Chang, Kyeong-Ok; Groutas, William C

    2016-03-10

    Human noroviruses are the primary causative agents of acute gastroenteritis and a pressing public health burden worldwide. There are currently no vaccines or small molecule therapeutics available for the treatment or prophylaxis of norovirus infections. Norovirus 3CL protease plays a vital role in viral replication by generating structural and nonstructural proteins via the cleavage of the viral polyprotein. Thus, molecules that inhibit the viral protease may have potential therapeutic value. We describe herein the structure-based design, synthesis, and in vitro and cell-based evaluation of the first class of oxadiazole-based, permeable macrocyclic inhibitors of norovirus 3CL protease.

  18. Identification of Cross-Reactive Norovirus CD4+ T Cell Epitopes ▿

    PubMed Central

    LoBue, Anna D.; Lindesmith, Lisa C.; Baric, Ralph S.

    2010-01-01

    Immune responses and the components of protective immunity following norovirus infection in humans are poorly understood. Although antibody responses following norovirus infection have been partially characterized, T cell responses in humans remain largely undefined. In contrast, T cells have been shown to be essential for viral clearance of mouse norovirus (MNV) infection. In this paper, we demonstrate that CD4+ T cells secrete gamma interferon (IFN-γ) in response to stimulation with MNV virus-like particles (VLPs) after MNV infection, supporting earlier reports for norovirus-infected mice and humans. Utilizing this model, we immunized mice with alphavirus vectors (Venezuelan equine encephalitis [VEE] virus replicon particles [VRPs]) expressing Norwalk virus (NV) or Farmington Hills virus (FH) virus-like particles to evaluate T cell epitopes shared between human norovirus strains. Stimulation of splenocytes from norovirus VRP-immunized mice with overlapping peptides from complete libraries of the NV or FH capsid proteins revealed specific amino acid sequences containing T cell epitopes that were conserved within genoclusters and genogroups. Immunization with heterologous norovirus VRPs resulted in specific cross-reactive IFN-γ secretion profiles following stimulation with NV and FH peptides in the mouse. Identification of unique strain-specific and cross-reactive epitopes may provide insight into homologous and heterologous T cell-mediated norovirus immunity and provide a platform for the study of norovirus-induced cellular immunity in humans. PMID:20573810

  19. High Mobility Group N Proteins Modulate the Fidelity of the Cellular Transcriptional Profile in a Tissue- and Variant-specific Manner*

    PubMed Central

    Kugler, Jamie E.; Horsch, Marion; Huang, Di; Furusawa, Takashi; Rochman, Mark; Garrett, Lillian; Becker, Lore; Bohla, Alexander; Hölter, Sabine M.; Prehn, Cornelia; Rathkolb, Birgit; Racz, Ildikó; Aguilar-Pimentel, Juan Antonio; Adler, Thure; Adamski, Jerzy; Beckers, Johannes; Busch, Dirk H.; Eickelberg, Oliver; Klopstock, Thomas; Ollert, Markus; Stöger, Tobias; Wolf, Eckhard; Wurst, Wolfgang; Yildirim, Ali Önder; Zimmer, Andreas; Gailus-Durner, Valérie; Fuchs, Helmut; Hrabě de Angelis, Martin; Garfinkel, Benny; Orly, Joseph; Ovcharenko, Ivan; Bustin, Michael

    2013-01-01

    The nuclei of most vertebrate cells contain members of the high mobility group N (HMGN) protein family, which bind specifically to nucleosome core particles and affect chromatin structure and function, including transcription. Here, we study the biological role of this protein family by systematic analysis of phenotypes and tissue transcription profiles in mice lacking functional HMGN variants. Phenotypic analysis of Hmgn1tm1/tm1, Hmgn3tm1/tm1, and Hmgn5tm1/tm1 mice and their wild type littermates with a battery of standardized tests uncovered variant-specific abnormalities. Gene expression analysis of four different tissues in each of the Hmgntm1/tm1 lines reveals very little overlap between genes affected by specific variants in different tissues. Pathway analysis reveals that loss of an HMGN variant subtly affects expression of numerous genes in specific biological processes. We conclude that within the biological framework of an entire organism, HMGNs modulate the fidelity of the cellular transcriptional profile in a tissue- and HMGN variant-specific manner. PMID:23620591

  20. Recovery optimization and survival of human norovirus surrogates, feline calicivirus and murine norovirus on carpet.

    PubMed

    Buckley, David; Fraser, Angela; Huang, Guohui; Jiang, Xiuping

    2017-09-01

    Carpet been attributed to prolonged and reoccurring outbreaks of human noroviruses (HuNoV), the leading cause of acute gastroenteritis worldwide. Viral recovery from environmental surfaces, such as carpet, remains undeveloped. Our aim was to determine survival of HuNoV surrogates on an understudied environmental surface, carpet. First, we measured the zeta potential and absorption capacity of wool and nylon carpet fibers, then developed a mini-spin column elution method (MSC), and lastly characterized the survival of HuNoV surrogates, feline calicivirus (FCV) and murine norovirus (MNV), over 60 days under 30 and 70% relative humidity (RH) on two types of carpet and one glass surface. Carpet surface charge was negative between relevant pH values (7 - 9). Additionally, wool could absorb ca. 2X more liquid than nylon. Percent recovery efficiency with the MSC ranged from 4.34 to 20.89% and 30.71 to 54.14% for FCV and MNV on carpet fibers, respectively, after desiccation. Overall, elution buffer type did not significantly affect recovery. Infectious FCV or MNV survived between <1 and 15 or 3 and 15 days, respectively. However, MNV survived longer under some conditions and at significantly (P <0.05) higher titers compared to FCV. Albeit, surrogates followed similar survival trends, i.e. both survived longest on wool then nylon and glass while 30% RH provided a more hospitable environment compared to 70% RH. RT-qPCR signals for both surrogates were detectable for the entire study but FCV genomic copies experienced significantly higher reductions (<3.80 log10 copies) on all surfaces compared to MNV (<1.10 log10 copies).IMPORTANCE Human noroviruses (HuNoV) are the leading cause of acute gastroenteritis worldwide. Classical symptoms of illness include vomiting and diarrhea which could lead to severe dehydration and death. HuNoV are transmitted by the fecal-oral or vomitus-oral route via person-to-person, food, water, and/or environmental surfaces. Published laboratory

  1. Noroviruses as a Cause of Diarrhea in Immunocompromised Pediatric Hematopoietic Stem Cell and Solid Organ Transplant Recipients

    PubMed Central

    Ye, Xunyan; Van, John N.; Munoz, Flor M.; Revell, Paula A.; Kozinetz, Claudia A; Krance, Robert A.; Atmar, Robert L.; Estes, Mary K.; Koo, Hoonmo L.

    2016-01-01

    Case reports describe significant norovirus gastroenteritis morbidity in immunocompromised patients. We evaluated norovirus pathogenesis in prospectively enrolled solid organ (SOT) and hematopoietic stem cell transplant (HSCT) patients with diarrhea who presented to Texas Children’s Hospital and submitted stool for enteric testing. Noroviruses were detected by real-time reverse transcription polymerase chain reaction. Clinical outcomes of norovirus diarrhea and non-norovirus diarrhea patients, matched by transplanted organ type, were compared. Norovirus infection was identified in 25 (22%) of 116 patients, more frequently than other enteropathogens. Fifty percent of norovirus patients experienced diarrhea lasting ≥14 days, with median duration of 12.5 days (range 1 – 324 days); 29% developed diarrhea recurrence. Fifty-five percent of norovirus patients were hospitalized for diarrhea, with 27% requiring intensive care unit (ICU) admission. One HSCT recipient developed pneumatosis intestinalis. Three HSCT patients expired ≤6 months of norovirus diarrhea onset. Compared to non-norovirus diarrhea patients, norovirus patients experienced significantly more frequent ICU admission (27% vs. 0%, p = 0.02), greater serum creatinine rise (median 0.3 vs. 0.2 mg/dL, p = 0.01), and more weight loss (median 1.6 vs. 0.6 kg, p < 0.01). Noroviruses are an important cause of diarrhea in pediatric transplant patients and are associated with significant clinical complications. PMID:25788003

  2. Resolution of diarrhea in an immunocompromised patient with chronic norovirus gastroenteritis correlates with constitution of specific antibody blockade titer.

    PubMed

    Knoll, Bettina M; Lindesmith, Lisa C; Yount, Boyd L; Baric, Ralph S; Marty, Francisco M

    2016-08-01

    Norovirus gastroenteritis in immunocompromised hosts can result in a serious and prolonged diarrheal illness. We present a case of chronic norovirus disease during rituximab-bendamustine chemotherapy for non-Hodgkin's lymphoma. We show for the first time a correlation between norovirus strain-specific antibody blockade titers and symptom improvement in an immunocompromised host.

  3. Detection and forecasting of oyster norovirus outbreaks: recent advances and future perspectives.

    PubMed

    Wang, Jiao; Deng, Zhiqiang

    2012-09-01

    Norovirus is a highly infectious pathogen that is commonly found in oysters growing in fecally contaminated waters. Norovirus outbreaks can cause the closure of oyster harvesting waters and acute gastroenteritis in humans associated with consumption of contaminated raw oysters. Extensive efforts and progresses have been made in detection and forecasting of oyster norovirus outbreaks over the past decades. The main objective of this paper is to provide a literature review of methods and techniques for detecting and forecasting oyster norovirus outbreaks and thereby to identify the future directions for improving the detection and forecasting of norovirus outbreaks. It is found that (1) norovirus outbreaks display strong seasonality with the outbreak peak occurring commonly in December-March in the U.S. and April-May in the Europe; (2) norovirus outbreaks are affected by multiple environmental factors, including but not limited to precipitation, temperature, solar radiation, wind, and salinity; (3) various modeling approaches may be employed to forecast norovirus outbreaks, including Bayesian models, regression models, Artificial Neural Networks, and process-based models; and (4) diverse techniques are available for near real-time detection of norovirus outbreaks, including multiplex PCR, seminested PCR, real-time PCR, quantitative PCR, and satellite remote sensing. The findings are important to the management of oyster growing waters and to future investigations into norovirus outbreaks. It is recommended that a combined approach of sensor-assisted real time monitoring and modeling-based forecasting should be utilized for an efficient and effective detection and forecasting of norovirus outbreaks caused by consumption of contaminated oysters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. [Survey on a public health emergency event caused by norovirus].

    PubMed

    Xing, Y; Jiang, C; Hua, W Y; Liu, F; Zhao, Z; Ding, Y J; Wang, L; Li, J

    2017-09-10

    Objective: To study the epidemiological characteristics of an outbreak caused by norovirus infection in a school in Haidian district, Beijing. Methods: Basic information of the school and data related to patients in the fields survey were collected and analyzed descriptively. Laboratory tests were performed to test the stool and anal swab specimens of both patients and cooks as well as the environmental specimens. Risk factors related to the incidence were analyzed through a case-control study. Results: A total number of 119 patients were identified in the school. Clinical symptoms were mild, mainly involving vomiting (94.1%, 112/119), abdominal pain (46.2%, 55/119), but no need of hospitalization. The average age of the student patients was 6.38, with minimum and maximum between 5 and 11. Patients were found in 22 classes, but mainly in grade 1 and class 7 where 35 patients were found (30.17%). A total of 134 specimens of rectal swabs and stool were collected, with 7 positive for norovirus and 6 for sappovirus. Salmonella, Shigella, lapactic Escherichia coli and Vibrio parahaemolyticus were not found in on dinner sets, residual foods, bottled water or in drinking fountains. Index on water hygiene was unsatisfactory in classrooms or dormitories where more cases were found. Accommodation, north-facing-classrooms, abnormal water hygiene indexes were found related to the occurance of the disease (P<0.05). Conclusions: The outbreak was identified a gastroenteritis infection, caused by norovirus with symptoms as vomiting and abdominal pain. This event reached the reporting standards of public health emergencies-level Ⅳ. Discovery and isolation of the first case was not timely while transmission of the disease might be water-borne. Surveillance programs on symptoms, disinfection of vomit and stool in places like nurseries and schools should be strengthened to prevent the norovirus outbreak.

  5. Norovirus outbreak associated with undercooked oysters and secondary household transmission.

    PubMed

    Alfano-Sobsey, E; Sweat, D; Hall, A; Breedlove, F; Rodriguez, R; Greene, S; Pierce, A; Sobsey, M; Davies, M; Ledford, S L

    2012-02-01

    During December 2009, over 200 individuals reported gastrointestinal symptoms after dining at a North Carolina restaurant. An outbreak investigation included a case-control study of restaurant patrons, a secondary household transmission study, environmental assessment of the restaurant facilities and operations, and laboratory analysis of stool and food samples. Illness was primarily associated with consumption of steamed oysters (odds ratio 12, 95% confidence interval 4·8-28) and 20% (8/41 households) reported secondary cases, with a secondary attack rate of 14% among the 70 susceptible household contacts. Norovirus RNA was detected in 3/5 stool specimens from ill patrons; sequencing of RT-PCR products from two of these specimens identified identical genogroup II genotype 12 sequences. Final cooked temperatures of the steamed oysters were generally inadequate to inactivate norovirus, ranging from 21°C to 74°C. Undercooked contaminated oysters pose a similar risk for norovirus illness as raw oysters and household contacts are at risk for secondary infection.

  6. In Vitro Cell Culture Infectivity Assay for Human Noroviruses

    SciTech Connect

    Straub, Tim M.; Honer Zu Bentrup, Kerstin A.; Orosz Coghlan, Patricia A.; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza; Nickerson, Cheryl A.

    2007-01-30

    Human noroviruses (NoV) cause severe, self-limiting gastroenteritis that typically lasts 24 - 48 hours. The true nature of NoV pathogenesis remains unknown due to the lack of suitable tissue culture or animal models. Here we show, for the first time, that NoV can infect and replicate in an organoid, three-dimensional (3-D) model of human small intestinal epithelium (INT-407). Cellular differentiation for this model was achieved by growing the cells in 3-D on porous collagen I-coated microcarrier beads under conditions of physiological fluid shear in rotating wall vessel bioreactors. Microscopy, PCR, and fluorescent in-situ hybridization were employed to provide evidence of NoV infection. CPE and norovirus RNA was detected at each of the five cell passages for both genogroup I and II viruses. Our results demonstrate that the highly differentiated 3-D cell culture model can support the natural growth of human noroviruses, whereas previous attempts using differentiated monolayer cultures failed.

  7. Disinfection kinetics of murine norovirus using chlorine and chlorine dioxide.

    PubMed

    Lim, Mi Young; Kim, Ju-Mi; Ko, Gwangpyo

    2010-05-01

    We determined the disinfection efficiency of chlorine and chlorine dioxide (ClO(2)) using murine norovirus (MNV) and coliphage MS2 as surrogates for human norovirus. Experiments were performed in oxidant demand-free buffer (pH 7.2) at 5 degrees C and 20 degrees C. The extent of virus inactivation by a disinfectant was quantified using three different analytical methods: plaque, short template real-time TaqMan reverse transcriptase-polymerase chain reaction (RT-PCR), and long template RT-PCR assays. Rapid inactivation of MNV by both chlorine and chlorine dioxide was observed by the plaque assay. According to the efficiency factor Hom model, Ct values of 0.314mg/Lmin and 0.247mg/Lmin were required for a 4-log reduction of MNV at 5 degrees C by chlorine and chlorine dioxide, respectively. Lower Ct values were required at 20 degrees C. Both long template and short template RT-PCR assays significantly underestimated the virus inactivation compared to the plaque assay. Our study demonstrates that adequate treatment of water with either chlorine or ClO(2) is likely to effectively control the waterborne transmission of human norovirus.

  8. Outbreak of norovirus illness associated with a swimming pool.

    PubMed

    Podewils, L J; Zanardi Blevins, L; Hagenbuch, M; Itani, D; Burns, A; Otto, C; Blanton, L; Adams, S; Monroe, S S; Beach, M J; Widdowson, M

    2007-07-01

    On 3 February 2004, the Vermont Department of Health received reports of acute gastroenteritis in persons who had recently visited a swimming facility. A retrospective cohort study was conducted among persons attending the facility between 30 January and 2 February. Fifty-three of 189 (28%) persons interviewed developed vomiting or diarrhoea within 72 h after visiting the facility. Five specimens tested positive for norovirus and three specimen sequences were identical. Entering the smaller of the two pools at the facility was significantly associated with illness (RR 5.67, 95% CI 1.5-22.0, P=0.012). The investigation identified several maintenance system failures: chlorine equipment failure, poorly trained operators, inadequate maintenance checks, failure to alert management, and insufficient record keeping. This study demonstrates the vulnerability of recreational water to norovirus contamination, even in the absence of any obvious vomiting or faecal accident. Our findings also suggest that norovirus is not as resistant to chlorine as previously reported in experimental studies. Appropriate regulations and enforcement, with adequate staff training, are necessary to ensure recreational water safety.

  9. Atmospheric cold plasma iactivation of norovirus surrogates and native microbiota on blueberries

    USDA-ARS?s Scientific Manuscript database

    Cold plasma (CP) is an emerging, novel, nonthermal technology that can be used for surface decontamination of foods. This study investigated CP technology for the nonthermal inactivation of the human norovirus surrogates, Tulane virus (TV) and Murine Norovirus (MNV), as well as for background microb...

  10. Inactivation of HAV and norovirus surrogates within raw shellfish and other foods

    USDA-ARS?s Scientific Manuscript database

    High pressure processing can inactivate hepatitis A virus, (HAV) and the human norovirus surrogates, feline calicivirus (FCV) and murine norovirus (MNV), in foods such as oysters, strawberries, and green onions. A 5-min 400-Megapascals (MPa) treatment at 5 degrees C and a 1–min 400-MPa treatment at ...

  11. Novel Platform Technologies for Analysis of Norovirus Contamination of Sea Food

    USDA-ARS?s Scientific Manuscript database

    The study of human norovirus (NoVs) replication in vitro would be a highly useful tool to virologists and immunologists. For this reason, we have searched for new approaches to determine viability of noroviruses in food samples (especially seafood). Our research team has multiple years of experien...

  12. Critical review of norovirus surrogates in food safety research: rationale for considering volunteer studies

    USDA-ARS?s Scientific Manuscript database

    The inability to propagate human norovirus (NoV) or to clearly differentiate infectious from noninfectious virus particles have led to the use of surrogate viruses, like feline calicivirus (FCV) and murine norovirus-1 (MNV), which are propagatable in cell culture. The use of surrogates is predicate...

  13. Digital PCR for Quantifying Norovirus in Oysters Implicated in Outbreaks, France

    PubMed Central

    Polo, David; Schaeffer, Julien; Fournet, Nelly; Le Saux, Jean-Claude; Parnaudeau, Sylvain; McLeod, Catherine

    2016-01-01

    Using samples from oysters clearly implicated in human disease, we quantified norovirus levels by using digital PCR. Concentrations varied from 43 to 1,170 RNA copies/oyster. The analysis of frozen samples from the production area showed the presence of norovirus 2 weeks before consumption. PMID:27869597

  14. Surface plasmon resonance biosensor for detection of feline calicivirus, a surrogate for norovirus

    USDA-ARS?s Scientific Manuscript database

    The human noroviruses are the most common non-bacterial cause of gastroenteritis and are responsible for as much as 50% of all gastroenteritis outbreaks worldwide. Norovirus (NoV), a single stranded RNA virus, is highly contagious with an infectious dose of less than 100 viral particles. While techn...

  15. Temperature-dependent persistence of human norovirus within oysters (Crassotrea virginica)

    USDA-ARS?s Scientific Manuscript database

    This study characterizes the persistence of human norovirus in Eastern oysters (Crassostrea virginica) held at different seawater temperatures. Oysters were contaminated with human norovirus GI.1 (Norwalk strain 8fIIa) by exposing them to virus contaminated water at 15 degrees C, and subsequently ho...

  16. Role of noroviruses as aetiological agents of diarrhoea in developing countries.

    PubMed

    Ayukekbong, James Ayukepi; Mesumbe, Henry Nzike; Oyero, Olufunmilayo G; Lindh, Magnus; Bergström, Tomas

    2015-08-01

    Diarrhoea is considered to be the second leading cause of death due to infections among children  < 5 years of age worldwide that may be caused by bacteria, parasites, viruses and non-infectious agents. The major causative agents of diarrhoea in developing countries may vary from those in developed countries. Noroviruses are considered to be the most common cause of acute diarrhoea in both children and adults in industrialized countries. On the other hand, there is a lack of comprehensive epidemiological evidence from developing countries that norovirus is a major cause of diarrhoea. In these regions, asymptomatic norovirus infections are very common, and similar detection rates have been observed in patients with diarrhoea and asymptomatic persons. This review summarizes the current knowledge of norovirus infection in developing countries and seeks to position infections with noroviruses among those of other enteropathogens in terms of disease burden in these regions.

  17. Inhibition of norovirus replication by morpholino oligomers targeting the 5′-end of the genome

    PubMed Central

    Bok, Karin; Cavanaugh, Victoria J.; Matson, David O.; González-Molleda, Lorenzo; Chang, Kyeong-Ok; Zintz, Carmelann; Smith, Alvin W.; Iversen, Patrick; Green, Kim Y.; Campbell, Ann E.

    2013-01-01

    Noroviruses are an important cause of non-bacterial epidemic gastroenteritis, but no specific antiviral therapies are available. We investigated the inhibitory effect of phosphorodiamidiate morpholino oligomers (PMOs) targeted against norovirus sequences. A panel of peptide-conjugated PMOs (PPMOs) specific for the murine norovirus (MNV) genome was developed, and two PPMO compounds directed against the first AUG of the ORF1 coding sequence near the 5′-end of the genome proved effective in inhibiting MNV replication in cells. A consensus PPMO (designated Noro 1.1), designed to target the corresponding region of several diverse human norovirus genotypes, decreased the efficiency of protein translation in a cell-free luciferase reporter assay and inhibited Norwalk virus protein expression in replicon-bearing cells. Our data suggest that PPMOs directed against the relatively conserved 5′-end of the norovirus genome may show broad antiviral activity against this genetically diverse group of viruses. PMID:18783811

  18. Comparative murine norovirus studies reveal a lack of correlation between intestinal virus titers and enteric pathology

    PubMed Central

    Kahan, Shannon M.; Liu, Guangliang; Reinhard, Mary K.; Hsu, Charlie C.; Livingston, Robert S.; Karst, Stephanie M.

    2011-01-01

    Human noroviruses are significant emerging pathogens, causing the majority of non-bacterial gastroenteritis outbreaks worldwide. The recent discovery of 30 murine norovirus strains is beginning to facilitate a detailed investigation of norovirus pathogenesis. Here, we have performed an in vivo comparative analysis of two murine norovirus strains, MNV-1 and MNV-3. In immunocompetent mice, MNV-1 caused modest intestinal pathology whereas MNV-3 was attenuated compared to MNV-1. Surprisingly though, MNV-3 reached higher titers in intestinal tissue than MNV-1. MNV-3 also displayed attenuation in mice deficient in the critical interferon signaling molecule STAT-1, demonstrating that MNV-3 attenuation is not a result of increased interferon sensitivity. Importantly, MNV-3-infected mice lost weight and developed gastric bloating and diarrhea in STAT1−/− mice, from which all animals recovered. This disease profile recapitulates several key features of acute gastroenteritis experienced by people infected with a human norovirus. PMID:22018636

  19. Comparative Evaluation of Real-Time PCR Methods for Human Noroviruses in Wastewater and Human Stool

    PubMed Central

    Konta, Yoshimitsu; Kazama, Shinobu; Inaba, Manami; Imagawa, Toshifumi; Tohma, Kentaro; Saito, Mayuko; Suzuki, Akira; Oshitani, Hitoshi; Omura, Tatsuo

    2016-01-01

    Selecting the best quantitative PCR assay is essential to detect human norovirus genome effectively from clinical and environmental samples because no cell lines have been developed to propagate this virus. The real-time PCR methods for noroviruses GI (4 assays) and GII (3 assays) were evaluated using wastewater (n = 70) and norovirus-positive stool (n = 77) samples collected in Japan between 2012 and 2013. Standard quantitative PCR assays recommended by the U.S. Environmental Protection Agency, International Organization for Standardization, and Ministry of Health, Labour and Welfare, Japan, together with recently reported assays were included. Significant differences in positive rates and quantification cycles were observed by non-parametric analysis. The present study identifies the best assay for norovirus GI and GII to amplify norovirus genomes efficiently. PMID:27525654

  20. Human Norovirus Interactions with Histo-Blood Group Antigens and Human Milk Oligosaccharides

    PubMed Central

    Schroten, Horst; Hanisch, Franz-Georg

    2016-01-01

    Human noroviruses interact with both human histo-blood group antigens (HBGAs) and human milk oligosaccharides (HMOs). The former are believed to be important for a virus infection, while the latter might act as natural decoys in the host during an infection. However, certain noroviruses are known to bind poorly to HBGAs and yet still cause infections; some interact with numerous HBGA types but are nonprevalent; and yet others bind HBGAs and seem to be increasing in prevalence. HBGAs and HMOs can be found as soluble antigens in humans, can be structurally alike, and can interact with equivalent residues at identical binding pockets on the capsid. In this Gem, we discuss HBGA and HMO binding studies for human noroviruses, concentrating on the clinically important genogroup II noroviruses. In short, the roles of HBGA and HMO interactions in norovirus infections are still unclear. PMID:27122582

  1. Sanitizer Efficacy against Murine Norovirus, a Surrogate for Human Norovirus, on Stainless Steel Surfaces when Using Three Application Methods

    PubMed Central

    Kotwal, Grishma; Harrison, Mark A.; Law, S. Edward; Harrison, Judy A.

    2013-01-01

    Human noroviruses are major etiologic agents of epidemic gastroenteritis. Outbreaks are often accompanied by contamination of environmental surfaces, but since these viruses cannot be routinely propagated in laboratory cultures, their response to surface disinfectants is predicted by using surrogates, such as murine norovirus 1 (MNV-1). This study compared the virucidal efficacies of various liquid treatments (three sanitizer liquids, 5% levulinic acid plus 2% SDS [LEV/SDS], 200 ppm chlorine, and an isopropanol-based quaternary ammonium compound [Alpet D2], and two control liquids, sterile tap water and sterile tap water plus 2% SDS) when delivered to MNV-1-inoculated stainless steel surfaces by conventional hydraulic or air-assisted, induction-charged (AAIC) electrostatic spraying or by wiping with impregnated towelettes. For the spray treatments, LEV/SDS proved effective when applied with hydraulic and AAIC electrostatic spraying, providing virus reductions of 2.71 and 1.66 log PFU/ml, respectively. Alpet D2 provided a 2.23-log PFU/ml reduction with hydraulic spraying, outperforming chlorine (1.16-log PFU/ml reduction). Chlorine and LEV/SDS were equally effective as wipes, reducing the viral load by 7.05 log PFU/ml. Controls reduced the viral load by <1 log with spraying applications and by >3 log PFU/ml with wiping. Results indicated that both sanitizer type and application methods should be carefully considered when choosing a surface disinfectant to best prevent and control environmental contamination by noroviruses. PMID:23263949

  2. Hydrogen Peroxide Vapor Decontamination in a Patient Room Using Feline Calicivirus and Murine Norovirus as Surrogate Markers for Human Norovirus.

    PubMed

    Holmdahl, Torsten; Walder, Mats; Uzcátegui, Nathalie; Odenholt, Inga; Lanbeck, Peter; Medstrand, Patrik; Widell, Anders

    2016-05-01

    To determine whether hydrogen peroxide vapor (HPV) could be used to decontaminate caliciviruses from surfaces in a patient room. Feline calicivirus (FCV) and murine norovirus (MNV) were used as surrogate viability markers to mimic the noncultivable human norovirus. Cell culture supernatants of FCV and MNV were dried in triplicate 35-mm wells of 6-well plastic plates. These plates were placed in various positions in a nonoccupied patient room that was subsequently exposed to HPV. Control plates were positioned in a similar room but were never exposed to HPV. Virucidal activity was measured in cell culture by reduction in 50% tissue culture infective dose titer for FCV and by both 50% tissue culture infective dose titer and plaque reduction for MNV. Neither viable FCV nor viable MNV could be detected in the test room after HPV treatment. At least 3.65 log reduction for FCV and at least 3.67 log reduction for MNV were found by 50% tissue culture infective dose. With plaque assay, measurable reduction for MNV was at least 2.85 log units. The successful inactivation of both surrogate viruses indicates that HPV could be a useful tool for surface decontamination of a patient room contaminated by norovirus. Hence nosocomial spread to subsequent patients can be avoided.

  3. Modeling and Prediction of Oyster Norovirus Outbreaks along Gulf of Mexico Coast.

    PubMed

    Wang, Jiao; Deng, Zhiqiang

    2016-05-01

    Oyster norovirus outbreaks often pose high risks to human health. However, little is known about environmental factors controlling the outbreaks, and little can be done to prevent the outbreaks because they are generally considered to be unpredictable. We sought to develop a mathematical model for predicting risks of oyster norovirus outbreaks using environmental predictors. We developed a novel probability-based Artificial Neural Network model, called NORF model, using 21 years of environmental and norovirus outbreak data collected from Louisiana oyster harvesting areas along the Gulf of Mexico coast, USA. The NORF model involves six input variables that were selected through stepwise regression analysis and sensitivity analysis. We found that the model-based probability of norovirus outbreaks was most sensitive to gage height (the depth of water in an oyster bed) and water temperature, followed by wind, rainfall, and salinity, respectively. The NORF model predicted all historical oyster norovirus outbreaks from 1994 through 2014. Specifically, norovirus outbreaks occurred when the NORF model probability estimate was > 0.6, whereas no outbreaks occurred when the estimated probability was < 0.5. Outbreaks may also occur when the estimated probability is 0.5-0.6. Our findings require further confirmation, but they suggest that oyster norovirus outbreaks may be predictable using the NORF model. The ability to predict oyster norovirus outbreaks at their onset may make it possible to prevent or at least reduce the risk of norovirus outbreaks by closing potentially affected oyster beds. Wang J, Deng Z. 2016. Modeling and prediction of oyster norovirus outbreaks along Gulf of Mexico coast. Environ Health Perspect 124:627-633; http://dx.doi.org/10.1289/ehp.1509764.

  4. Modeling and Prediction of Oyster Norovirus Outbreaks along Gulf of Mexico Coast

    PubMed Central

    Wang, Jiao; Deng, Zhiqiang

    2015-01-01

    Background: Oyster norovirus outbreaks often pose high risks to human health. However, little is known about environmental factors controlling the outbreaks, and little can be done to prevent the outbreaks because they are generally considered to be unpredictable. Objective: We sought to develop a mathematical model for predicting risks of oyster norovirus outbreaks using environmental predictors. Methods: We developed a novel probability-based Artificial Neural Network model, called NORF model, using 21 years of environmental and norovirus outbreak data collected from Louisiana oyster harvesting areas along the Gulf of Mexico coast, USA. The NORF model involves six input variables that were selected through stepwise regression analysis and sensitivity analysis. Results: We found that the model-based probability of norovirus outbreaks was most sensitive to gage height (the depth of water in an oyster bed) and water temperature, followed by wind, rainfall, and salinity, respectively. The NORF model predicted all historical oyster norovirus outbreaks from 1994 through 2014. Specifically, norovirus outbreaks occurred when the NORF model probability estimate was > 0.6, whereas no outbreaks occurred when the estimated probability was < 0.5. Outbreaks may also occur when the estimated probability is 0.5–0.6. Conclusions: Our findings require further confirmation, but they suggest that oyster norovirus outbreaks may be predictable using the NORF model. The ability to predict oyster norovirus outbreaks at their onset may make it possible to prevent or at least reduce the risk of norovirus outbreaks by closing potentially affected oyster beds. Citation: Wang J, Deng Z. 2016. Modeling and prediction of oyster norovirus outbreaks along Gulf of Mexico coast. Environ Health Perspect 124:627–633; http://dx.doi.org/10.1289/ehp.1509764 PMID:26528621

  5. Microfluidic platform integrated with graphene-gold nano-composite aptasensor for one-step detection of norovirus.

    PubMed

    Chand, Rohit; Neethirajan, Suresh

    2017-12-15

    Noroviruses are a foremost cause of gastroenteritis outbreaks throughout the world. On-site sample processing and detection of the viral clinical samples has always been a problem. This study reports an all-polydimethylsiloxane microfluidic chip integrated with screen-printed carbon electrode for the electrochemical detection of norovirus. The microfluidic chip contained packed silica microbeads zones to filter and enrich the norovirus infected clinical sample. Selective detection of norovirus was accomplished by functionalizing the graphene-gold nanoparticles composite modified carbon electrode with the viral capsid-specific aptamer. Norovirus specific aptamer was tagged with a ferrocene molecule, which acts a redox probe. The interaction of aptamer and norovirus resulted in a decrease in the electrochemical signal from ferrocene. The microfluidic chip and functionalized electrodes were characterized using several microscopic and electrochemical techniques. The optimized microfluidic aptasensor was employed to detect a range of norovirus concentration. Using differential pulse voltammetric analysis, a detection limit of 100 pM with a detection range from 100 pM to 3.5nM for norovirus was obtained. The application of aptasensor was also assessed by detecting norovirus in spiked blood samples. The aptasensor could easily discriminate between the target norovirus and other interfering molecules. The developed microfluidic aptasensor has the potential to be used for point-of-care one-step detection of norovirus in clinical samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Effects of disinfectants against norovirus virus-like particles predict norovirus inactivation.

    PubMed

    Sato, Jun; Miki, Motohiro; Kubota, Hiromi; Hitomi, Jun; Tokuda, Hajime; Todaka-Takai, Reiko; Katayama, Kazuhiko

    2016-09-01

    Human noroviruses (NoVs) are a major cause of epidemic and sporadic acute gastroenteritis worldwide. Public and personal hygiene is one of the most important countermeasures for preventing spread of NoV infection. However, no a practicable cell culture system for NoV had been developed, initial tests of the virucidal effectiveness of anti-NoV disinfectants and sanitizers have been performed using surrogate viruses. In this study, NoV virus-like particles (VLPs) were used as a new surrogate for NoVs and a method for evaluating NoV inactivation using them developed. This method is based on morphological changes in VLPs after treatment with sodium hypochlorite. VLP specimens were found to become deformed and degraded in a concentration-dependent manner. Based on these results, the effects of sodium hypochlorite on VLPs were classified into four phases according to morphological changes and number of particles. Using the criteria thus established, the efficacy of ethanol, carbonates and alkali solutions against VLPs was evaluated. Deformation and aggregation of VLPs were observed after treatment with these disinfectants under specific conditions. To determine the degradation mechanism(s), VLPs were examined by SDS-PAGE and immunoblotting after treatment with sodium hypochlorite and ethanol. The band corresponding to the major capsid protein, VP1, was not detected after treatment with sodium hypochlorite at concentrations greater than 500 ppm, but remained after treatment with ethanol. These results suggest that VLPs have excellent potential as a surrogate marker for NoVs and can be used in initial virucidal effectiveness tests to determine the mechanism(s) of chemical agents on NoVs. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

  7. Multisite outbreak of norovirus associated with a franchise restaurant--Kent County, Michigan, May 2005.

    PubMed

    2006-04-14

    The majority of cases of foodborne gastroenteritis in the United States are caused by noroviruses. This report summarizes an investigation by the Kent County Health Department (KCHD) in Michigan into three norovirus outbreaks and a cluster of community cases that were associated with a national submarine sandwich franchise restaurant during May 3-9, 2005. The investigation identified a potential source, a food handler who had returned to work within a few hours of having symptoms of gastrointestinal illness while he was still excreting norovirus in his stools. To prevent norovirus outbreaks, food service workers should be educated regarding norovirus transmission and control. In 2005, new guidelines for state health departments regarding norovirus containment were published by the Food and Drug Administration (FDA); guidelines for local health departments in Michigan were issued by the state's Department of Community Health and Department of Agriculture. The new guidelines for Michigan recommend that food service workers with suspected norovirus not return to work until they are asymptomatic for 48-72 hours.

  8. Human Norovirus prevalence in Africa: a review of studies from 1990 to 2013.

    PubMed

    Kabue, Jean Pierre; Meader, Emma; Hunter, Paul R; Potgieter, Natasha

    2016-01-01

    To assess the contribution of Human Norovirus to diarrhoeal diseases in Africa. We conducted a systematic review of the PubMed and EMBASE databases for published articles of Human Norovirus in Africa between 1990 and 2013. Data were extracted from selected studies and analysed. A total of 208 eligible studies were identified, of which 55 (from 19 countries) met the inclusion criteria. Many cases were of sporadic gastroenteritis (70.9%) in children (82%), 65.4% of which were seen in an outpatient setting. Over half (59.4%) of the affected children were under 5 years of age. The pooled prevalence rate of Human NoV was 11% (95% CI 8-14%), and the meta-analysis indicated significant heterogeneity between the studies. However, the conditional negative binomial regression could not clearly find the factors affecting the Human NoV prevalence rates reported. A close relationship was found between Human Norovirus strains from environmental and clinical samples. Unreported sporadic gastroenteritis cases of Human Norovirus are common in Africa. Most are community-associated infections. Possible environmental transmission routes have been documented. Combined environmental and clinical studies are required for targeted actions to control transmission of Human Norovirus in Africa. Systematic surveillance of Human Norovirus is needed to measure the burden of Norovirus-induced gastroenteritis in Africa and support any requirements for vaccine development. © 2015 John Wiley & Sons Ltd.

  9. Environmental factors associated with childhood norovirus diarrhoea in León, Nicaragua.

    PubMed

    Becker-Dreps, S; Cuthbertson, C C; Bucardo, F; Vinje, J; Paniagua, M; Giebultowicz, S; Espinoza, F; Emch, M

    2017-06-01

    Norovirus is detected in one in five diarrhoea episodes in children, yet little is known about environmental risk factors associated with this disease, especially in low-income settings. The objective of this study was to examine environmental risk factors, and spatial and seasonal patterns of norovirus diarrhoea episodes in children in León, Nicaragua. We followed a population-based cohort of children under age 5 years for norovirus diarrhoea over a 1-year period. At baseline, characteristics of each household were recorded. Households were geocoded and spatial locations of garbage dumps, rivers, and markets were collected. In bivariate analysis we observed younger children and those with animals in their households were more likely to have experienced norovirus episodes. In adjusted models, younger children remained at higher risk for norovirus episodes, but only modest associations were observed with family and environmental characteristics. We next identified symptomatic children living in the same household and within 500 m buffer zones around the household of another child infected with the same genotype. Norovirus diarrhoea episodes peaked early in the rainy season. These findings contribute to our understanding of environmental factors and norovirus infection.

  10. Epidemiology of foodborne Norovirus outbreaks in Catalonia, Spain

    PubMed Central

    Martinez, Ana; Dominguez, Angela; Torner, Nuria; Ruiz, Laura; Camps, Neus; Barrabeig, Irene; Arias, Cesar; Alvarez, Josep; Godoy, Pere; Balaña, Pilar Jorgina; Pumares, Analia; Bartolome, Rosa; Ferrer, Dolors; Perez, Unai; Pinto, Rosa; Buesa, Javier

    2008-01-01

    Background Noroviruses are one of the principal biological agents associated with the consumption of contaminated food. The objective of this study was to analyse the size and epidemiological characteristics of foodborne outbreaks of gastroenteritis in Catalonia, a region in the northeast of Spain. Methods In all reported outbreaks of gastroenteritis associated with food consumption, faecal samples of persons affected were analysed for bacteria and viruses and selectively for parasites. Study variables included the setting, the number of people exposed, age, sex, clinical signs and hospital admissions. The study was carried out from October 2004 to October 2005. Results Of the 181 outbreaks reported during the study period, 72 were caused by Salmonella and 30 by norovirus (NoV); the incidence rates were 14.5 and 9.9 per 100,000 person-years, respectively. In 50% of the NoV outbreaks and 27% of the bacterial outbreaks (p = 0.03) the number of persons affected was ≥10; 66.7% of NoV outbreaks occurred in restaurants; no differences in the attack rates were observed according to the etiology. Hospitalizations were more common (p = 0.03) in bacterial outbreaks (8.6%) than in NoV outbreaks (0.15%). Secondary cases accounted for 4% of cases in NoV outbreaks compared with 0.3% of cases in bacterial outbreaks (p < 0.001) Conclusion Norovirus outbreaks were larger but less frequent than bacterial outbreaks, suggesting that underreporting is greater for NoV outbreaks. Food handlers should receive training on the transmission of infections in diverse situations. Very strict control measures on handwashing and environmental disinfection should be adopted in closed or partially-closed institutions. PMID:18410687

  11. Mapping Broadly Reactive Norovirus Genogroup I and II Monoclonal Antibodies

    PubMed Central

    Crawford, Sue E.; Ajami, Nadim; Parker, Tracy Dewese; Kitamoto, Noritoshi; Natori, Katsuro; Takeda, Naokazu; Tanaka, Tomoyuki; Kou, Baijun; Atmar, Robert L.

    2014-01-01

    Noroviruses are responsible for most acute nonbacterial epidemic outbreaks of gastroenteritis worldwide. To develop cross-reactive monoclonal antibodies (MAbs) for rapid identification of genogroup I and II (GI and GII) noroviruses (NoVs) in field specimens, mice were immunized with baculovirus-expressed recombinant virus-like particles (VLPs) corresponding to NoVs. Nine MAbs against the capsid protein were identified that detected both GI and GII NoV VLPs. These MAbs were tested in competition enzyme-linked immunosorbent assays (ELISAs) to identify common epitope reactivities to GI and GII VLPs. Patterns of competitive reactivity placed these MAbs into two epitope groups (groups 1 and 2). Epitopes for MAbs NV23 and NS22 (group 1) and MAb F120 (group 2) were mapped to a continuous region in the C-terminal P1 subdomain of the capsid protein. This domain is within regions previously defined to contain cross-reactive epitopes in GI and GII viruses, suggesting that common epitopes are clustered within the P1 domain of the capsid protein. Further characterization in an accompanying paper (B. Kou et al., Clin Vaccine Immunol 22:160–167, 2015, http://dx.doi.org/10.1128/CVI.00519-14) revealed that MAb NV23 (epitope group 1) is able to detect GI and GII viruses in stool. Inclusion of the GI and GII cross-reactive MAb NV23 in antigen detection assays may facilitate the identification of GI and GII human noroviruses in stool samples as causative agents of outbreaks and sporadic cases of gastroenteritis worldwide. PMID:25428246

  12. Biodegradable nanogels for oral delivery of interferon for norovirus infection

    PubMed Central

    Kim, Yunjeong; Thapa, Mahendra; Hua, Duy H; Chang, Kyeong-Ok

    2010-01-01

    Norwalk virus (NV) replicon-harboring cells have provided an excellent tool to the development of antivirals. Previously we demonstrated that the expression levels of replicon RNA and proteins were significantly reduced in the presence of various interferons (IFNs) including IFN-α and IFN-γ in a dose-dependent manner in the NV replicon-harboring cells, and suggested that IFNs could be therapeutic options for norovirus infection. It was also demonstrated that innate immunity including IFNs is crucial in the replication and pathogenicity of murine norovirus (MNV) in vitro (RAW267.4 cells) and in vivo. IFNs have a short half-life in vitro and in vivo due to low stability. Thus it is important to have a good delivery system to improve the stability of IFNs. Nanogels are nanosized networks of chemically cross-linked polymers that swell in physiologic solutions and provide improved stability and bioavailability to drugs. We have synthesized nanogels based on cross-linked polyethyleneimine (PEI)-polyethylenglycol (PEG). The PEI/PEG nanogels were further acetylated (AcNg) to reduce cellular penetration and cytotoxicity. The IFN-AcNg complex was prepared by incubating two components together at 4 °C and lyophilization. The IFN activity of IFN-AcNg was evaluated in the NV- and HCV-replicon-harboring cells and against MNV-1 in RAW267.4 cells in comparison to IFN without AcNg. The AcNg improved the stability of IFN stored at 4 °C, and was well tolerated in the cells. Furthermore, the activity of IFN was significantly higher when combined with AcNg in the replicon-harboring cells and against MNV-1 in RAW267.4 cells. We concluded that AcNg may be pursued further as a vehicle for oral delivery of IFNs in norovirus infection. PMID:21144866

  13. Mechanisms of antiviral action of plant antimicrobials against murine norovirus.

    PubMed

    Gilling, Damian H; Kitajima, Masaaki; Torrey, Jason R; Bright, Kelly R

    2014-08-01

    Numerous plant compounds have antibacterial or antiviral properties; however, limited research has been conducted with nonenveloped viruses. The efficacies of allspice oil, lemongrass oil, and citral were evaluated against the nonenveloped murine norovirus (MNV), a human norovirus surrogate. The antiviral mechanisms of action were also examined using an RNase I protection assay, a host cell binding assay, and transmission electron microscopy. All three antimicrobials produced significant reductions (P ≤ 0.05) in viral infectivity within 6 h of exposure (0.90 log10 to 1.88 log10). After 24 h, the reductions were 2.74, 3.00, and 3.41 log10 for lemongrass oil, citral, and allspice oil, respectively. The antiviral effect of allspice oil was both time and concentration dependent; the effects of lemongrass oil and citral were time dependent. Based on the RNase I assay, allspice oil appeared to act directly upon the viral capsid and RNA. The capsids enlarged from ≤ 35 nm to up to 75 nm following treatment. MNV adsorption to host cells was not significantly affected. Alternatively, the capsid remained intact following exposure to lemongrass oil and citral, which appeared to coat the capsid, causing nonspecific and nonproductive binding to host cells that did not lead to successful infection. Such contrasting effects between allspice oil and both lemongrass oil and citral suggest that though different plant compounds may yield similar reductions in virus infectivity, the mechanisms of inactivation may be highly varied and specific to the antimicrobial. This study demonstrates the antiviral properties of allspice oil, lemongrass oil, and citral against MNV and thus indicates their potential as natural food and surface sanitizers to control noroviruses. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Mechanisms of Antiviral Action of Plant Antimicrobials against Murine Norovirus

    PubMed Central

    Gilling, Damian H.; Kitajima, Masaaki; Torrey, Jason R.

    2014-01-01

    Numerous plant compounds have antibacterial or antiviral properties; however, limited research has been conducted with nonenveloped viruses. The efficacies of allspice oil, lemongrass oil, and citral were evaluated against the nonenveloped murine norovirus (MNV), a human norovirus surrogate. The antiviral mechanisms of action were also examined using an RNase I protection assay, a host cell binding assay, and transmission electron microscopy. All three antimicrobials produced significant reductions (P ≤ 0.05) in viral infectivity within 6 h of exposure (0.90 log10 to 1.88 log10). After 24 h, the reductions were 2.74, 3.00, and 3.41 log10 for lemongrass oil, citral, and allspice oil, respectively. The antiviral effect of allspice oil was both time and concentration dependent; the effects of lemongrass oil and citral were time dependent. Based on the RNase I assay, allspice oil appeared to act directly upon the viral capsid and RNA. The capsids enlarged from ≤35 nm to up to 75 nm following treatment. MNV adsorption to host cells was not significantly affected. Alternatively, the capsid remained intact following exposure to lemongrass oil and citral, which appeared to coat the capsid, causing nonspecific and nonproductive binding to host cells that did not lead to successful infection. Such contrasting effects between allspice oil and both lemongrass oil and citral suggest that though different plant compounds may yield similar reductions in virus infectivity, the mechanisms of inactivation may be highly varied and specific to the antimicrobial. This study demonstrates the antiviral properties of allspice oil, lemongrass oil, and citral against MNV and thus indicates their potential as natural food and surface sanitizers to control noroviruses. PMID:24907316

  15. Mapping broadly reactive norovirus genogroup I and II monoclonal antibodies.

    PubMed

    Crawford, Sue E; Ajami, Nadim; Parker, Tracy Dewese; Kitamoto, Noritoshi; Natori, Katsuro; Takeda, Naokazu; Tanaka, Tomoyuki; Kou, Baijun; Atmar, Robert L; Estes, Mary K

    2015-02-01

    Noroviruses are responsible for most acute nonbacterial epidemic outbreaks of gastroenteritis worldwide. To develop cross-reactive monoclonal antibodies (MAbs) for rapid identification of genogroup I and II (GI and GII) noroviruses (NoVs) in field specimens, mice were immunized with baculovirus-expressed recombinant virus-like particles (VLPs) corresponding to NoVs. Nine MAbs against the capsid protein were identified that detected both GI and GII NoV VLPs. These MAbs were tested in competition enzyme-linked immunosorbent assays (ELISAs) to identify common epitope reactivities to GI and GII VLPs. Patterns of competitive reactivity placed these MAbs into two epitope groups (groups 1 and 2). Epitopes for MAbs NV23 and NS22 (group 1) and MAb F120 (group 2) were mapped to a continuous region in the C-terminal P1 subdomain of the capsid protein. This domain is within regions previously defined to contain cross-reactive epitopes in GI and GII viruses, suggesting that common epitopes are clustered within the P1 domain of the capsid protein. Further characterization in an accompanying paper (B. Kou et al., Clin Vaccine Immunol 22:160-167, 2015, http://dx.doi.org/10.1128/CVI.00519-14) revealed that MAb NV23 (epitope group 1) is able to detect GI and GII viruses in stool. Inclusion of the GI and GII cross-reactive MAb NV23 in antigen detection assays may facilitate the identification of GI and GII human noroviruses in stool samples as causative agents of outbreaks and sporadic cases of gastroenteritis worldwide. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. Likely transmission of norovirus on an airplane, October 2008.

    PubMed

    Kirking, Hannah L; Cortes, Jennifer; Burrer, Sherry; Hall, Aron J; Cohen, Nicole J; Lipman, Harvey; Kim, Curi; Daly, Elizabeth R; Fishbein, Daniel B

    2010-05-01

    On 8 October 2008, members of a tour group experienced diarrhea and vomiting throughout an airplane flight from Boston, Massachusetts, to Los Angeles, California, resulting in an emergency diversion 3 h after takeoff. An investigation was conducted to determine the cause of the outbreak, assess whether transmission occurred on the airplane, and describe risk factors for transmission. Passengers and crew were contacted to obtain information about demographics, symptoms, locations on the airplane, and possible risk factors for transmission. Case patients were defined as passengers with vomiting or diarrhea (> or =3 loose stools in 24 h) and were asked to submit stool samples for norovirus testing by real-time reverse-transcription polymerase chain reaction. Thirty-six (88%) of 41 tour group members were interviewed, and 15 (41%) met the case definition (peak date of illness onset, 8 October 2008). Of 106 passengers who were not tour group members, 85 (80%) were interviewed, and 7 (8%) met the case definition after the flight (peak date of illness onset, 10 October 2008). Multivariate logistic regression analysis showed that sitting in an aisle seat (adjusted relative risk, 11.0; 95% confidence interval, 1.4-84.9) and sitting near any tour group member (adjusted relative risk, 7.5; 95% confidence interval, 1.7-33.6) were associated with the development of illness. Norovirus genotype II was detected by reverse-transcription polymerase chain reaction in stool samples from case patients in both groups. Despite the short duration, transmission of norovirus likely occurred during the flight.

  17. Norovirus Infection and Acquired Immunity in 8 Countries: Results From the MAL-ED Study.

    PubMed

    Rouhani, Saba; Peñataro Yori, Pablo; Paredes Olortegui, Maribel; Siguas Salas, Mery; Rengifo Trigoso, Dixner; Mondal, Dinesh; Bodhidatta, Ladaporn; Platts-Mills, James; Samie, Amidou; Kabir, Furqan; Lima, Aldo; Babji, Sudhir; Mason, Carl J; Kalam, Adil; Bessong, Pascal; Ahmed, Tahmeed; Mduma, Estomih; Bhutta, Zulfiqar A; Lima, Ila; Ramdass, Rakhi; Lang, Dennis; George, Ajila; Zaidi, Anita K M; Kang, Gagandeep; Houpt, Eric; Kosek, Margaret N

    2016-05-15

    Norovirus is an important cause of childhood diarrhea. We present data from a longitudinal, multicountry study describing norovirus epidemiology during the first 2 years of life. A birth cohort of 1457 children across 8 countries contributed 7077 diarrheal stools for norovirus testing. A subset of 199 children contributed additional asymptomatic samples (2307) and diarrheal stools (770), which were used to derive incidence rates and evaluate evidence for acquired immunity. Across sites, 89% of children experienced at least 1 norovirus infection before 24 months, and 22.7% of all diarrheal stools were norovirus positive. Severity of norovirus-positive diarrhea was comparable to other enteropathogens, with the exception of rotavirus. Incidence of genogroup II (GII) infection was higher than genogroup I and peaked at 6-11 months across sites. Undernutrition was a risk factor for symptomatic norovirus infection, with an increase in 1 standard deviation of length-for-age z score associated with a 17% reduction (odds ratio, 0.83 [95% confidence interval, .72-.97]; P = .011) in the odds of experiencing diarrhea when norovirus was present, after accounting for genogroup, rotavirus vaccine, and age. Evidence of acquired immunity was observed among GII infections only: Children with prior GII infection were found to have a 27% reduction in the hazard of subsequent infection (hazard ratio, 0.727; P = .010). The high prevalence of norovirus across 8 sites in highly variable epidemiologic settings and demonstration of protective immunity for GII infections provide support for investment in vaccine development. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

  18. Norovirus Capture with Histo-Blood Group Antigens Reveals Novel Virus-Ligand Interactions

    PubMed Central

    Harrington, Patrick R.; Vinjé, Jan; Moe, Christine L.; Baric, Ralph S.

    2004-01-01

    Noroviruses are genetically diverse, uncultivable, positive-sense RNA viruses and are the most common cause of epidemic acute gastroenteritis in humans in the United States. Recent studies of norovirus attachment in vitro by using recombinant virus-like particles (VLPs) suggest that various norovirus strains exhibit different patterns of attachment to ABH histo-blood group antigens, which are carbohydrate epitopes present in high concentrations on mucosal cell surfaces of the gut. However, attachment of live norovirus strains to histo-blood group antigens has not been investigated to date. Utilizing a newly designed magnetic bead-virus capture method, we characterized histo-blood group antigen attachment properties of various norovirus strains obtained from clinical stool specimens to compare the attachment properties of wild-type virus and VLPs and to further map norovirus attachment. Consistent with previous reports using VLPs, various strains of noroviruses exhibited different patterns of attachment to histo- blood group antigens. Norwalk virus bound specifically to H type 1, H type 3, and Leb. Two genogroup II noroviruses, one representing the Toronto genotype and the other from a novel genotype, bound specifically to Leb. A Desert Shield-like strain did not attach to H types 1, 2, or 3, H type 1 and 3 precursors, Lea, or Leb. Surprisingly, wild-type Snow Mountain virus (SMV) attached specifically to H type 3, which contradicted previous findings with SMV VLPs. On further investigation, we found that stool components promote this attachment, providing the first known observation that one or more components of human feces could promote and enhance norovirus attachment to histo-blood group antigens. PMID:14990722

  19. Modelling Estimates of Norovirus Disease in Patients with Chronic Medical Conditions

    PubMed Central

    Verstraeten, Thomas; Jiang, Baoguo; Weil, John G.; Lin, Jennifer H.

    2016-01-01

    Background The burden of disease due to norovirus infection has been well described in the general United States population, but studies of norovirus occurrence among persons with chronic medical conditions have been limited mostly to the immunocompromised. We assessed the impact of norovirus gastroenteritis on health care utilization in US subjects with a range of chronic medical conditions. Methods We performed a retrospective cohort study using MarketScan data from July 2002 to December 2013, comparing the rates of emergency department visits, outpatient visits and hospitalizations among patients with chronic conditions (renal, cardiovascular, respiratory, immunocompromising, gastrointestinal, hepatic/pancreatic and neurological conditions and diabetes) with those in a healthy population. We estimated the rates of these outcomes due to norovirus gastroenteritis using an indirect modelling approach whereby cases of gastroenteritis of unknown cause and not attributed to a range of other causes were assumed to be due to norovirus. Results Hospitalization rates for norovirus gastroenteritis were higher in all of the risk groups analyzed compared with data in otherwise healthy subjects, ranging from 3.2 per 10,000 person-years in persons with chronic respiratory conditions, to 23.1 per 10,000 person-years in persons with chronic renal conditions, compared to 2.1 per 10,000 among persons without chronic conditions. Over 51% of all norovirus hospitalizations occurred in the 37% of the population with some form of chronic medical condition. Outpatient visits for norovirus gastroenteritis were also increased in persons with chronic gastrointestinal or immunocompromising conditions. Conclusion Norovirus gastroenteritis leads to significantly higher rates of healthcare utilization in patients with a chronic medical condition compared to patients without any such condition. PMID:27438335

  20. Regulation of Norovirus Virulence by the VP1 Protruding Domain Correlates with B Cell Infection Efficiency

    PubMed Central

    Zhu, Shu; Watanabe, Makiko; Kirkpatrick, Ericka; Murray, Akilah B.; Sok, Ryneth

    2015-01-01

    ABSTRACT Human noroviruses are a leading cause of gastroenteritis across the globe, but the pathogenic mechanisms responsible for disease are not well established. The availability of a murine norovirus model system provides the opportunity to elucidate viral and host determinants of virulence in a natural host. For example, previous studies have revealed that the protruding domain of the murine norovirus capsid protein VP1, specifically residue 296 of VP1, regulates virulent infection. We identified a panel of nonsynonymous mutations in the open reading frame 2 (ORF2) gene encoding VP1 that arose in persistently infected mice and tested whether these mutations conferred phenotypic changes to viral replication and virulence. Consistent with previous studies, we demonstrate that a glutamic acid at position 296 results in attenuation. For the first time, we also demonstrate that a lysine at this position is sufficient to confer virulence on an otherwise attenuated murine norovirus strain. Moreover, our studies reveal a direct correlation between the efficiency of viral replication in B cells and virulence. These data are especially striking because mutations causing reduced B cell replication and attenuation had minimal effects on the ability of the virus to replicate in macrophages. Thus, norovirus infection of B cells may directly contribute to disease outcome. IMPORTANCE Human noroviruses are a major global cause of disease, yet we know very little about their pathogenic mechanisms. The availability of a murine norovirus model system facilitates investigation of noroviruses in a natural host organism and the identification of viral and host determinants of pathogenesis. We have identified a panel of mutations arising in the viral capsid protein VP1 during persistent infection of mice. Our data reveal that the protruding domain of VP1 regulates the ability of the virus to replicate in B cells, and this directly correlates with virulence. Importantly, mutations

  1. Norovirus Infection and Acquired Immunity in 8 Countries: Results From the MAL-ED Study

    PubMed Central

    Rouhani, Saba; Peñataro Yori, Pablo; Paredes Olortegui, Maribel; Siguas Salas, Mery; Rengifo Trigoso, Dixner; Mondal, Dinesh; Bodhidatta, Ladaporn; Platts-Mills, James; Samie, Amidou; Kabir, Furqan; Lima, Aldo; Babji, Sudhir; Mason, Carl J.; Kalam, Adil; Bessong, Pascal; Ahmed, Tahmeed; Mduma, Estomih; Bhutta, Zulfiqar A.; Lima, Ila; Ramdass, Rakhi; Lang, Dennis; George, Ajila; Zaidi, Anita K. M.; Kang, Gagandeep; Houpt, Eric; Kosek, Margaret N.

    2016-01-01

    Background. Norovirus is an important cause of childhood diarrhea. We present data from a longitudinal, multicountry study describing norovirus epidemiology during the first 2 years of life. Methods. A birth cohort of 1457 children across 8 countries contributed 7077 diarrheal stools for norovirus testing. A subset of 199 children contributed additional asymptomatic samples (2307) and diarrheal stools (770), which were used to derive incidence rates and evaluate evidence for acquired immunity. Results. Across sites, 89% of children experienced at least 1 norovirus infection before 24 months, and 22.7% of all diarrheal stools were norovirus positive. Severity of norovirus-positive diarrhea was comparable to other enteropathogens, with the exception of rotavirus. Incidence of genogroup II (GII) infection was higher than genogroup I and peaked at 6–11 months across sites. Undernutrition was a risk factor for symptomatic norovirus infection, with an increase in 1 standard deviation of length-for-age z score associated with a 17% reduction (odds ratio, 0.83 [95% confidence interval, .72–.97]; P = .011) in the odds of experiencing diarrhea when norovirus was present, after accounting for genogroup, rotavirus vaccine, and age. Evidence of acquired immunity was observed among GII infections only: Children with prior GII infection were found to have a 27% reduction in the hazard of subsequent infection (hazard ratio, 0.727; P = .010). Conclusions. The high prevalence of norovirus across 8 sites in highly variable epidemiologic settings and demonstration of protective immunity for GII infections provide support for investment in vaccine development. PMID:27013692

  2. Genetically distinct genogroup IV norovirus strains identified in wastewater.

    PubMed

    Kitajima, Masaaki; Rachmadi, Andri T; Iker, Brandon C; Haramoto, Eiji; Gerba, Charles P

    2016-12-01

    We investigated the prevalence and genetic diversity of genogroup IV norovirus (GIV NoV) strains in wastewater in Arizona, United States, over a 13-month period. Among 50 wastewater samples tested, GIV NoVs were identified in 13 (26 %) of the samples. A total of 47 different GIV NoV strains were identified, which were classified into two genetically distinct clusters: the GIV.1 human cluster and a unique genetic cluster closely related to strains previously identified in Japanese wastewater. The results provide additional evidence of the considerable genetic diversity among GIV NoV strains through the analysis of wastewater containing virus strains shed from all populations.

  3. Protective role of murine norovirus against Pseudomonas aeruginosa acute pneumonia.

    PubMed

    Thépaut, Marion; Grandjean, Teddy; Hober, Didier; Lobert, Pierre-Emmanuel; Bortolotti, Perrine; Faure, Karine; Dessein, Rodrigue; Kipnis, Eric; Guery, Benoit

    2015-09-04

    The murine norovirus (MNV) is a recently discovered mouse pathogen, representing the most common contaminant in laboratory mouse colonies. Nevertheless, the effects of MNV infection on biomedical research are still unclear. We tested the hypothesis that MNV infection could alter immune response in mice with acute lung infection. Here we report that co-infection with MNV increases survival of mice with Pseudomonas aeruginosa acute lung injury and decreases in vivo production of pro-inflammatory cytokines. Our results suggest that MNV infection can deeply modify the parameters studied in conventional models of infection and lead to false conclusions in experimental models.

  4. Knowledge of norovirus prevention and control among infection preventionists.

    PubMed

    Kosa, Katherine M; Cates, Sheryl C; Hall, Aron J; Brophy, Jenna E; Frasier, Angela

    2014-06-01

    A Web-based survey was administered to infection preventionists (IPs) (N = 941) to characterize awareness and knowledge of norovirus (NoV). Only 44% of respondents correctly identified NoV as one of the 3 most common foodborne pathogens in the United States, and 5% correctly identified the 3 most common settings for NoV outbreaks. Several gaps in IPs' knowledge of NoV were identified; specifically, IPs could benefit from learning more about the natural history of NoV, modes of transmission, and cleaning and disinfection processes. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. All rights reserved.

  5. Two-Year Systematic Study To Assess Norovirus Contamination in Oysters from Commercial Harvesting Areas in the United Kingdom

    PubMed Central

    Gustar, Nicole E.; Powell, Andrew L.; Hartnell, Rachel E.; Lees, David N.

    2012-01-01

    The contamination of bivalve shellfish with norovirus from human fecal sources is recognized as an important human health risk. Standardized quantitative methods for the detection of norovirus in molluscan shellfish are now available, and viral standards are being considered in the European Union and internationally. This 2-year systematic study aimed to investigate the impact of the application of these methods to the monitoring of norovirus contamination in oyster production areas in the United Kingdom. Twenty-four monthly samples of oysters from 39 United Kingdom production areas, chosen to represent a range of potential contamination risk, were tested for norovirus genogroups I and II by using a quantitative real-time reverse transcription (RT)-PCR method. Norovirus was detected in 76.2% (643/844) of samples, with all sites returning at least one positive result. Both prevalences (presence or absence) and norovirus levels varied markedly between sites. However, overall, a marked winter seasonality of contamination by both prevalence and quantity was observed. Correlations were found between norovirus contamination and potential risk indicators, including harvesting area classifications, Escherichia coli scores, and environmental temperatures. A predictive risk score for norovirus contamination was developed by using a combination of these factors. In summary, this study, the largest of its type undertaken to date, provides a systematic analysis of norovirus contamination in commercial oyster production areas in the United Kingdom. The data should assist risk managers to develop control strategies to reduce the risk of human illness resulting from norovirus contamination of bivalve molluscs. PMID:22685151

  6. Quantification of Human Norovirus GII on Hands of Mothers with Children Under the Age of Five Years in Bagamoyo, Tanzania.

    PubMed

    Mattioli, Mia Catharine M; Davis, Jennifer; Mrisho, Mwifadhi; Boehm, Alexandria B

    2015-09-01

    Human noroviruses are the most common cause of viral gastroenteritis worldwide and one of the leading causes of viral diarrhea in children under the age of 5 years. Hands have been shown to play an important role in norovirus transmission. Norovirus outbreaks tend to exhibit strong seasonality, most often occurring during cold, dry months, but recently have also been documented during hot, dry winter months in the southern hemisphere. Other research suggests that rainfall is an important factor in norovirus outbreaks. This study examines the prevalence and concentration of human norovirus GII on the hands of mothers in Bagamoyo, Tanzania, during the rainy and dry seasons. Norovirus GII was detected in approximately 5% of hand rinse samples during both the rainy and dry seasons. Fecal indicator bacteria levels, Escherichia coli and enterococci, in hand rinse samples were not associated with norovirus hand contamination. Turbidity of the hand rinses was found to be associated with norovirus presence on mothers' hands; however, this relationship was only observed during the rainy season. The