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PubMed | University of Limoges, Hospices Civils de Lyon, Montpellier University, Assistance Publique Hopitaux de Paris and 11 more.
Type: Journal Article | Journal: Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases | Year: 2016

Group A rotavirus (RVA) is the leading cause of acute gastroenteritis in young children worldwide. A prospective surveillance network has been set up to investigate the virological and clinical features of RVA infections and to detect the emergence of potentially epidemic strains in France. From 2009 to 2014, RVA-positive stool samples were collected from 4800 children <5 years old attending the paediatric emergency units of 16 large hospitals. Rotaviruses were then genotyped by RT-PCR with regard to their outer capsid proteins VP4 and VP7. Genotyping of 4708 RVA showed that G1P[8] strains (62.2%) were predominant. The incidence of G9P[8] (11.5%), G3P[8] (10.4%) and G2P[4] (6.6%) strains varied considerably, whereas G4P[8] (2.7%) strains were circulating mostly locally. Of note, G12P[8] (1.6%) strains emerged during the seasons 2011-12 and 2012-13 with 4.1% and 3.0% prevalence, respectively. Overall, 40 possible zoonotic reassortants, such as G6 (33.3%) and G8 (15.4%) strains, were detected, and were mostly associated with P[6] (67.5%). Analysis of clinical records of 624 hospitalized children and severity scores from 282 of them showed no difference in clinical manifestations or severity in relation to the genotype. The relative stability of RVA genotypes currently co-circulating and the large predominance of P[8] type strains may ensure vaccine effectiveness in France. The surveillance will continue to monitor the emergence of new reassortants that might not respond to current vaccines, all the more so as all genotypes can cause severe infections in infants.


Roos-Weil D.,Center dInfectiologie Necker Pasteur | Ambert-Balay K.,Center National Of Reference Des Virus Enteriques | Lanternier F.,Center dInfectiologie Necker Pasteur | Lanternier F.,University of Paris Descartes | And 19 more authors.
Transplantation | Year: 2011

Background: Diarrhea of unspecified cause frequently occurs after renal transplantation and is usually ascribed to mycophenolic acid toxicity. Norovirus (NoV) and sapovirus (SaV) have been sporadically reported to cause chronic diarrhea in immunocompromised patients. Methods: We undertook a retrospective study (2008-2009) to examine the clinical and epidemiologic significance of NoV and SaV infections in adult renal transplant recipients hospitalized for acute or chronic diarrhea. Results: Ninety-six renal transplant recipients were hospitalized for diarrhea at our institution during a 16-month period, 87 of whom were included in the study, including 46 patients with chronic diarrhea. Among 41 patients with unexplained diarrhea, 20 patients were screened for NoV/SaV, 16 of whom were positive. Fifteen of them (94%) had chronic diarrhea. When compared with bacterial and parasitic infections, NoV/SaV infections were associated with a greater weight loss at the time of admission, a 8.7-fold longer duration of symptoms and a more frequent need for mycophenolic acid dosage reduction. Eighty-one percent of patients hospitalized for NoV/SaV-associated diarrhea experienced acute renal failure. Five and one patients subsequently had biopsy-diagnosed active graft rejection and oxalate nephropathy, respectively. Ten of the 14 patients who underwent a longitudinal study of NoV/SaV stool's clearance exhibited a prolonged viral shedding period with a median time of 289 days (107-581 days). Conclusions: Our study indicates that NoV/SaV infection causes posttransplant chronic diarrhea potentially complicated by severe kidney graft impairment. © 2011 by Lippincott Williams & Wilkins.


Ruvoen-Clouet N.,National School of Engineering in Agricultural and Food Industries | Ruvoen-Clouet N.,French Institute of Health and Medical Research | Belliot G.,Center National Of Reference Des Virus Enteriques | Le Pendu J.,French Institute of Health and Medical Research
Reviews in Medical Virology | Year: 2013

SUMMARY: Noroviruses (NoVs) are recognized as a leading cause of human gastroenteritis worldwide. Infection occurs following the ingestion of contaminated food or, most often, through direct contact from person to person. However, not all individuals are equally sensitive to these viruses. Indeed, NoVs use glycans of the ABH and Lewis histo-blood group antigen family (HBGAs) as attachment factors. At the epithelial level, the synthesis of these HBGAs requires the action of several glycosyltransferases that are encoded by the ABO, FUT2, and FUT3 genes. The combined polymorphism at these three loci dictates sensitivity to NoV infection because the attachment profile to these glycans varies among strains. Structural analysis of the capsid protein interaction with HBGAs reveals distinct modes of binding for strains of genogroups I and II but high conservation within each genogroup, whereas minor amino acid changes are sufficient to generate modifications of HBGA-binding specificities or affinities. Such modifications therefore induce changes in the spectrum of susceptible individuals. Studies of NoV-HBGA interactions together with phylogenetic analyses and the epidemiologic survey of strains indicate that NoV transmission and evolution depend on both the establishment of herd immunity and the genetic resistance of many individuals, which confers herd innate protection by restricting NoV circulation. © 2013 John Wiley & Sons, Ltd.


Ruvoen-Clouet N.,National School of Engineering in Agricultural and Food Industries | Ruvoen-Clouet N.,University of Nantes | Belliot G.,Center National Of Reference Des Virus Enteriques | Le Pendu J.,University of Nantes
Virologie | Year: 2013

Norovirus (NoVs) are recognized as a leading cause of human gastroenteritis worldwide. Infection takes place following ingestion of contaminated food or most often through direct contact from person to person. However, not all individuals are equally sensitive to these viruses. Indeed, NoVs use ABH and Lewis glycans of the histo-blood group antigen family (HBGAs) as ligands. At the epithelial level synthesis of these HBGAs requires the action of several glycosyltransferases encoded by the ABO, FUT2 and FUT3 genes. Since the attachment profile to these glycans varies from strain to strain, the combined polymorphism at these three loci dictates sensitivity to NoV infection. Studies of the NoV-HBGA interactions together with phylogenetic analyses and the epidemiologic follow-up of strains indicate that NoVs transmission and evolution depends both on the establishment of herd immunity and on the genetic resistance of many individuals that contributes to restrict NoVs circulation, confering a herd innate proctection.


Ayouni S.,Center National Of Reference Des Virus Enteriques | Ayouni S.,University of Monastir | Estienney M.,Center National Of Reference Des Virus Enteriques | Hammami S.,University of Monastir | And 8 more authors.
PLoS ONE | Year: 2016

Three newly discovered viruses have been recently described in diarrheal patients: Cosavirus (CosV) and Salivirus (SalV), two picornaviruses, and Bufavirus (BuV), a parvovirus. The detection rate and the role of these viruses remain to be established in acute gastroenteritis (AGE) in diarrheal Tunisian infants. From October 2010 through March 2012, stool samples were collected from 203 children <5 years-old suffering from AGE and attending the Children's Hospital in Monastir, Tunisia. All samples were screened for CosV, SalV and BuV as well as for norovirus (NoV) and group A rotavirus (RVA) by molecular biology. Positive samples for the three screened viruses were also tested for astrovirus, sapovirus, adenovirus, and Aichi virus, then genotyped when technically feasible. During the study period, 11 (5.4%) samples were positive for one of the three investigated viruses: 2 (1.0%) CosVA10, 7 (3.5%) SalV-A1 and 2 (1.0%) BuV-1, whereas 71 (35.0%) children were infected with NoV and 50 (24.6%) with RVA. No mixed infections involving the three viruses were found, but multiple infections with up to 4 classic enteric viruses were found in all cases. Although these viruses are suspected to be responsible for AGE in children, our data showed that this association was uncertain since all infected children also presented infections with several enteric viruses, suggesting here potential water-borne transmission. Therefore, further studies with large cohorts of healthy and diarrheal children will be needed to evaluate their clinical role in AGE. © 2016 Ayouni et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Barret A.S.,Institute of Veille Sanitaire | Jourdan-Da Silva N.,Institute of Veille Sanitaire | Ambert-Balay K.,Center National Of Reference Des Virus Enteriques | Delmas G.,Institute of Veille Sanitaire | And 4 more authors.
Eurosurveillance | Year: 2014

This article describes outbreaks of gastroenteritis in elderly long-term care facilities (LTCF) in France from November 2010 to May 2012 reported through the surveillance system for gastroenteritis outbreaks in LTCF. A total of 1,072 outbreaks were reported, causing 26,551 episodes of illness and 60 deaths. The median attack rate (AR) among residents was 32%. Norovirus and person-to-person transmission were the most frequently reported aetiology and mode of transmission. Control measures were implemented in 1,054 (98%) outbreaks and for 928 outbreaks, the timing of such measures could be inferred. Of these, 799 (86%) had put control measures into effect within three days of the occurrence of the first case. Outbreaks of gastroenteritis in LTCF cause substantial morbidity and mortality among elderly people in France. LTCF are encouraged to develop infection prevention and control plans and to notify any gastroenteritis outbreak to health authorities to ensure rapid control. © 2007-2013. All rights reserved.


Ronchetti A.-M.,University Pierre and Marie Curie | Henry B.,University Pierre and Marie Curie | Ambert-Balay K.,Center National Of Reference Des Virus Enteriques | Pothier P.,Center National Of Reference Des Virus Enteriques | And 3 more authors.
BMC Infectious Diseases | Year: 2014

Background: Norovirus infection is increasingly recognized as an important cause of persistent gastroenteritis in immunocompromised hosts and can be a potential cause of morbidity in these populations.Case presentation: Here, we report a case of norovirus-related chronic diarrhea occurring in a 62-year-old immunocompromised patient treated with alemtuzumab for chronic lymphocytic leukemia. Despite different therapeutic strategies including tapering of immunosuppressive therapy and immunoglobulin administration, diarrhea unfortunately did not resolve and lasted for a total of more than twelve weeks with prolonged norovirus fecal excretion.Conclusions: Norovirus infection can occur in the setting of alemtuzumab treatment, even as a single agent, and should be included in the differential diagnoses of acute and chronic diarrhea in these immunocompromised patients. Although the administration of oral immunoglobulin has been described as a promising efficient therapy, this was not the case in our patient. Clinical trials are thus clearly warranted to better define risk factors and efficient therapies for norovirus infection in immunocompromised populations. © 2014 Ronchetti et al.; licensee BioMed Central Ltd.


PubMed | Center National Of Reference Des Virus Enteriques
Type: Journal Article | Journal: Bulletin de l'Academie nationale de medecine | Year: 2011

Rotaviruses and noroviruses are the main causes of acute gastroenteritis in young children and adults, respectively. Prospective molecular surveillance of rotavirus genotypes in France and Europe shows that circulating strains may vary with the season, locality or country. Rotavirus OK? genotypes G1 and G9 are the most prevalent. Most strains are associated with P[8], showing a certain genotypic stability of rotaviruses currently circulating in Europe and suggesting that vaccination would be effective at least in the short and medium term. However, atypical strains G12 and G8 must be monitored in case they emerge in future. Noroviruses belong to the Caliciviridae family. These single-stranded RNA viruses show major genetic diversity. they are divided into 5 genogroups, which are themselves subdivided into genotypes. In addition, new variants are continually arising, and are frequently associated with new epidemic waves of gastroenteritis.


PubMed | University of Monastir and Center National Of Reference Des Virus Enteriques
Type: Journal Article | Journal: PloS one | Year: 2016

Three newly discovered viruses have been recently described in diarrheal patients: Cosavirus (CosV) and Salivirus (SalV), two picornaviruses, and Bufavirus (BuV), a parvovirus. The detection rate and the role of these viruses remain to be established in acute gastroenteritis (AGE) in diarrheal Tunisian infants. From October 2010 through March 2012, stool samples were collected from 203 children <5 years-old suffering from AGE and attending the Childrens Hospital in Monastir, Tunisia. All samples were screened for CosV, SalV and BuV as well as for norovirus (NoV) and group A rotavirus (RVA) by molecular biology. Positive samples for the three screened viruses were also tested for astrovirus, sapovirus, adenovirus, and Aichi virus, then genotyped when technically feasible. During the study period, 11 (5.4%) samples were positive for one of the three investigated viruses: 2 (1.0%) CosV-A10, 7 (3.5%) SalV-A1 and 2 (1.0%) BuV-1, whereas 71 (35.0%) children were infected with NoV and 50 (24.6%) with RVA. No mixed infections involving the three viruses were found, but multiple infections with up to 4 classic enteric viruses were found in all cases. Although these viruses are suspected to be responsible for AGE in children, our data showed that this association was uncertain since all infected children also presented infections with several enteric viruses, suggesting here potential water-borne transmission. Therefore, further studies with large cohorts of healthy and diarrheal children will be needed to evaluate their clinical role in AGE.


Pothier P.,Center National Of Reference Des Virus Enteriques
Bulletin de l'Academie Nationale de Medecine | Year: 2010

Rotaviruses and noroviruses are the main causes of acute gastroenteritis in young children and adults, respectively. Prospective molecular surveillance of rotavirus genotypes in France and Europe shows that circulating strains may vary with the season, locality or country. Rotavirus OK? genotypes G1 and G9 are the most prevalent. Most strains are associated with P[8], showing a certain genotypic stability of rotaviruses currently circulating in Europe and suggesting that vaccination would be effective at least in the short and medium -term. However, atypical strains G12 and G8 must be monitored in case they emerge in future. Noroviruses belong to the Caliciviridae family. These single-stranded RNA viruses show major genetic diversity: they are divided into 5 genogroups, which are themselves subdivided into genotypes. In addition, new variants are continually arising, and are frequently associated with new epidemic waves of gastroenteritis.

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