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Registros recuperados: 10 | |
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Desdouits, Marion; Wacrenier, Candice; Ollivier, Joanna; Schaeffer, Julien; Le Guyader, Soizick. |
Human noroviruses (NoV) cause epidemics of acute gastroenteritis (AGE) worldwide and can be transmitted through consumption of contaminated foods. Fresh products such as shellfish can be contaminated by human sewage during production, which results in the presence of multiple virus strains, at very low concentrations. Here, we tested a targeted metagenomics approach by deep-sequencing PCR amplicons of the capsid (VP1) and polymerase (RdRp) viral genes, on a set of artificial samples and on shellfish samples associated to AGE outbreaks, to evaluate its advantages and limitations in the identification of strains from the NoV genogroup (G) II. Using artificial samples, the method allowed the sequencing of most strains, but not all, and displayed variability... |
Tipo: Text |
Palavras-chave: Norovirus; Foodborne virus; Metagenomics; Amplicon deep sequencing; Viral diversity. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00646/75831/76818.pdf |
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Grodzki, Marco; Schaeffer, Julien; Piquet, Jean-come; Le Saux, Jean-claude; Cheve, Julien; Ollivier, Joanna; Le Pendu, Jacques; Le Guyader, Soizick. |
Hepatitis E virus (HEV), an enteric pathogen of both humans and animals, is excreted by infected individuals and is therefore present in wastewaters and coastal waters. As bivalve molluscan shellfish are known to concentrate viral particles during the process of filter feeding, they may accumulate this virus. The bioaccumulation efficiencies of oysters (Crassostrea gigas), flat oysters (Ostrea edulis), mussels (Mytilus edulis), and clams (Ruditapes philippinarum) were compared at different time points during the year. Tissue distribution analysis showed that most of the viruses were concentrated in the digestive tissues of the four species. Mussels and clams were found to be more sensitive to sporadic contamination events, as demonstrated by rapid... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00204/31501/29905.pdf |
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Le Guyader, Soizick; Garry, Pascal; Ollivier, Joanna; Piquet, Jean-come. |
The shellfish safety has long been considered a public health problem. The implementation of a regulation based on a bacterial indicator of faecal contamination has significantly reduced outbreaks of bacterial origin. However, epidemics of viral gastroenteritis due to the presence of noroviruses from human sewage persist. We demonstrated few years ago that oysters are not just a passive filter but are able to select some viral strains, via the presence of specific ligands, very similar to ligands observed in humans for these same virus. Ongoing developments, in conjunction with the application of metagenomic tools, will allow us to better understand the fate of some human pathogens after their release into the coastal environment. |
Tipo: Text |
Palavras-chave: Shellfish; Microbiology; Oysters; Norovirus. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00599/71141/69457.pdf |
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Benabbes, Laila; Ollivier, Joanna; Schaeffer, Julien; Parnaudeau, Sylvain; Rhaissi, Houria; Nourlil, Jalal; Le Guyader, Soizick. |
The aim of this study was to evaluate the presence of human enteric viruses in shellfish collected along the Mediterranean Sea and Atlantic Coast of Morocco. A total of 77 samples were collected from areas potentially contaminated by human sewage. Noroviruses were detected in 30 % of samples, with an equal representation of GI and GII strains, but were much more frequently found in cockles or clams than in oysters. The method used, including extraction efficiency controls, allowed the quantification of virus concentration. As in previous reports, results showed levels of contamination between 100 and 1,000 copies/g of digestive tissues. Sapoviruses were detected in 13 % of samples mainly in oyster and clam samples. Hepatitis A virus was detected in two... |
Tipo: Text |
Palavras-chave: Shellfish; Norovirus; Hepatitis A virus; Environmental conditions; Quantification; Morocco. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00130/24102/22489.pdf |
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Teunis, Peter Fm; Le Guyader, Soizick; Liu, Pengbo; Ollivier, Joanna; Moe, Christine L. |
Noroviruses are a major public health concern: their high infectivity and environmental persistence have been documented in several studies. Genetic sequencing shows that noroviruses are highly variable, and exhibit rapid evolution. A few human challenge studies have been performed with norovirus, leading to estimates of their infectivity. However, such incidental estimates do not provide insight into the biological variation of the virus and the interaction with its human host. To study the variation in infectivity and pathogenicity of norovirus, multiple challenge studies must be analysed jointly, to compare their differences and describe how virus infectivity and host susceptibility vary. Since challenge studies can only provide a small sample of the... |
Tipo: Text |
Palavras-chave: Challenge studies; Infectivity; Natural experiments; Norovirus; Multilevel dose response. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00641/75265/75474.pdf |
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Randazzo, Walter; Khezri, Mohammad; Ollivier, Joanna; Le Guyader, Soizick; Rodriguez-diaz, Jesus; Aznar, Rosa; Sanchez, Gloria. |
Shellfish contamination by human noroviruses (HuNoVs) is a serious health and economic problem. Recently an ISO procedure based on RT-qPCR for the quantitative detection of HuNoVs in shellfish has been issued, but these procedures cannot discriminate between inactivated and potentially infectious viruses. The aim of the present study was to optimize a pretreatment using PMAxx to better discriminate between intact and heat-treated HuNoVs in shellfish and sewage. To this end, the optimal conditions (30 min incubation with 100 μM of PMAxx and 0.5% of Triton, and double photoactivation) were applied to mussels, oysters and cockles artificially inoculated with thermally-inactivated (99 °C for 5 min) HuNoV GI and GII. This pretreatment reduced the signal of... |
Tipo: Text |
Palavras-chave: Intercalating dyes; Viability PCR; Norovirus; Shellfish; Sewage; RT-qPCR. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00411/52208/52970.pdf |
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Desdouits, Marion; Garry, Pascal; Gourmelon, Michele; Hervio Heath, Dominique; Hubert, Francoise; Kaelin, Gaelle; Kergaravat, Cedric; Le Mennec, Cecile; Le Guyader, Soizick; Loiseau, Veronique; Lozach, Solen; Maillot, Jessica; Ollivier, Joanna; Parnaudeau, Sylvain; Piquet, Jean-come; Quenot, Emmanuelle; Rocq, Sophie; Schaeffer, Julien; Serghine, Joelle; Vallade, Emilie; Veron, Antoine; Wacrenier, Candice. |
Ce rapport présente une synthèse des actions, et travaux réalisés par le laboratoire Santé Environnement et Microbiologie pendant l’année 2018. Les divers projets de recherche sont résumés et les derniers développements ou résultats sont brièvement évoqués. Les actions en tant que Laboratoire National de Référence pour la Microbiologie des Coquillages et les activités pour la coordination du réseau REMI sont également présentées. |
Tipo: Text |
Palavras-chave: Microbiologie sanitaire; Bactéries entériques; Vibrions; Virus entériques humains; Norovirus; Coquillage; Activité de référence; REMI.. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00491/60218/63584.pdf |
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Lowther, J. A.; Bosch, A.; Butot, S.; Ollivier, Joanna; Maede, D.; Rutjes, S. A.; Hardouin, G.; Lombard, B.; In'T Veld, P.; Leclercq, A.. |
Hepatitis A virus (HAV) and norovirus are important agents of food-borne human viral illness, with common vehicles including bivalve molluscan shellfish, soft fruit and various vegetables. Outbreaks of viral illness due to contamination of the surfaces of foods, or food preparation surfaces by for example infected food handlers are also common. Virus analysis of food matrices can contribute towards risk management for these hazards and a two-part technical specification for determination of Hepatitis A virus and norovirus in food matrices (ISO/TS 15216:2013) was published jointly by the European Committee for Standardisation and the International Organization for Standardization in 2013. As part of the European Mandate No. M381 to validate 15 standards in... |
Tipo: Text |
Palavras-chave: Norovirus; Hepatitis A virus; Real-time RT-PCR; Validation; Standardization; Bivalve molluscan shellfish; Soft fruit; Vegetables; Bottled water; Surfaces. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00476/58776/61442.pdf |
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Registros recuperados: 10 | |
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