Demonstration of Viral Contamination of Oysters Responsible for an Outbreak of Viral Gastroenteritis

1981 ◽  
Vol 44 (4) ◽  
pp. 294-296 ◽  
Author(s):  
M. J. EYLES ◽  
G. R. DAVEY ◽  
E. J. HUNTLEY

Two viruses, echovirus type 8 and a reovirus, were isolated from a batch of oysters responsible for an outbreak of gastroenteritis. Characteristics of the illness, detection of Norwalk virus in the feces of one of the victims and other factors indicated strongly that the illness was due to infection with Norwalk virus. Examination of the implicated oysters and a fecal specimen from a victim failed to provide evidence of the involvement of any other causative agent. Thus laboratory evidence of human enteric virus contamination of a batch of food responsible for a viral illness has been provided.

1985 ◽  
Vol 48 (9) ◽  
pp. 815-823 ◽  
Author(s):  
GARY P. RICHARDS

Outbreaks of hepatitis A, Norwalk illness, and nonspecific viral gastroenteritis are associated with consumption of sewage-contaminated shellfish. Over 100 outbreaks have been reported in the United States during the past 50 years. Reported cases of shellfish-associated enteric virus illness are on the increase, whereas bacterial illness from shellfish is on the decline. As yet, there are no procedures for detecting hepatitis A virus, Norwalk virus and numerous other pathogenic viruses in environmental samples, but virus extraction and assay procedures for water and shellfish are available for the more easily cultivated enteric viruses. Current standards rely on bacterial indicators as a means to evaluate the sanitary quality of shellfish and their growing waters, but the adequacy of using bacteria as indicators of possible virus contamination is questionable. The feasibility of employing enteroviruses or rotaviruses as possible viral indiators is discussed. It is proposed that easily cultivated enteroviruses, such as poliovirus, be used as an interim indicator for the possible presence of human pathogenic viruses in seafoods, with the subsequent formulation of guidelines to limit the levels of virus contamination in shellfish.


2004 ◽  
Vol 67 (10) ◽  
pp. 2315-2319 ◽  
Author(s):  
FRANÇOISE S. LE GUYADER ◽  
ANNA-CHARLOTTE SCHULTZ ◽  
LARISSA HAUGARREAU ◽  
LUCIANA CROCI ◽  
LEENA MAUNULA ◽  
...  

Five methods that detect human enteric virus contamination in lettuce were compared. To mimic multiple contaminations as observed after sewage contamination, artificial contamination was with human calicivirus and poliovirus and animal calici-virus strains at different concentrations. Nucleic acid extractions were done at the same time in the same laboratory to reduce assay-to-assay variability. Results showed that the two critical steps are the washing step and removal of inhibitors. The more reliable methods (sensitivity, simplicity, low cost) included an elution/concentration step and a commercial kit. Such development of sensitive methods for viral detection in foods other than shellfish is important to improve food safety.


1998 ◽  
Vol 38 (12) ◽  
pp. 51-56 ◽  
Author(s):  
K. Henshilwood ◽  
J. Green ◽  
D. N. Lees

This study investigates human enteric virus contamination of a shellfish harvesting area. Samples were analysed over a 14-month period for Small Round Structured Viruses (SRSVs) using a previously developed nested RT-PCR. A clear seasonal difference was observed with the largest numbers of positive samples obtained during the winter period (October to March). This data concurs with the known winter association of gastroenteric illness due to oyster consumption in the UK and also with the majority of the outbreaks associated with shellfish harvested from this area during the study period. RT-PCR positive amplicons were further characterised by cloning and sequencing. Sequence analysis of the positive samples identified eleven SRSV strains, of both Genogroup I and Genogroup II, occurring throughout the study period. Many shellfish samples contained a mixture of strains with a few samples containing up to three different strains with both Genogroups represented. The observed common occurrence of strain mixtures may have implications for the role of shellfish as a vector for dissemination of SRSV strains. These results show that nested RT-PCR can identify SRSV contamination in shellfish harvesting areas. Virus monitoring of shellfish harvesting areas by specialist laboratories using RT-PCR is a possible approach to combating the transmission of SRSVs by molluscan shellfish and could potentially offer significantly enhanced levels of public health protection.


1994 ◽  
Vol 113 (1) ◽  
pp. 143-151 ◽  
Author(s):  
S. P. Parker ◽  
W. D. Cubitt

SUMMARYAn enzyme immunoassay employing recombinant Norwalk virus capsid protein was evaluated for the measurement of IgA responses. Tests on 23 volunteers and patients known to have been infected with Norwalk virus (NV) showed that 19 developed significant IgA responses, 2 had unchanging levels of IgA and 2 failed to respond. There was no evidence of IgA responses to NV following infection with Hawaii or Snow Mountain-like viruses.Tests on sera from patients involved in outbreaks associated with eating contaminated shellfish suggest that some patients may have been infected with more than one strain of calicivirus. The use of the rNV EIA for measuring IgA and IgG responses in patients involved in a major outbreak of food poisoning affecting hospital staff indicated that the causative agent was probably NV.


Viruses ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 104
Author(s):  
Georges Tarris ◽  
Alexis de Rougemont ◽  
Maëva Charkaoui ◽  
Christophe Michiels ◽  
Laurent Martin ◽  
...  

Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD), is a multifactorial disease in which dietary, genetic, immunological, and microbial factors are at play. The role of enteric viruses in IBD remains only partially explored. To date, epidemiological studies have not fully described the role of enteric viruses in inflammatory flare-ups, especially that of human noroviruses and rotaviruses, which are the main causative agents of viral gastroenteritis. Genome-wide association studies have demonstrated the association between IBD, polymorphisms of the FUT2 and FUT3 genes (which drive the synthesis of histo-blood group antigens), and ligands for norovirus and rotavirus in the intestine. The role of autophagy in defensin-deficient Paneth cells and the perturbations of cytokine secretion in T-helper 1 and T-helper 17 inflammatory pathways following enteric virus infections have been demonstrated as well. Enteric virus interactions with commensal bacteria could play a significant role in the modulation of enteric virus infections in IBD. Based on the currently incomplete knowledge of the complex phenomena underlying IBD pathogenesis, future studies using multi-sampling and data integration combined with new techniques such as human intestinal enteroids could help to decipher the role of enteric viruses in IBD.


2000 ◽  
Vol 66 (8) ◽  
pp. 3241-3248 ◽  
Author(s):  
F. Le Guyader ◽  
L. Haugarreau ◽  
L. Miossec ◽  
E. Dubois ◽  
M. Pommepuy

ABSTRACT The main pathogenic enteric viruses able to persist in the environment, such as hepatitis A virus (HAV), Norwalk-like virus (NLV), enterovirus (EV), rotavirus (RV), and astrovirus (AV), were detected by reverse transcription-PCR and hybridization in shellfish during a 3-year study. Oyster samples (n = 108), occasionally containing bacteria, were less frequently contaminated, showing positivity for AV (17%), NLV (23%), EV (19%), and RV (27%), whereas mussel samples, collected in areas routinely impacted by human sewage, were more highly contaminated: AV (50%), HAV (13%), NLV (35%), EV (45%), and RV (52%). Sequences obtained from HAV and NLV amplicons showed a great variety of strains, especially for NLV (strains close to Mexico, Snow Mountain Agent, or Norwalk virus). Viral contamination was mainly observed during winter months, although there were some seasonal differences among the viruses. This first study of virus detection over a fairly long period of time suggests that routine analysis of shellfish by a molecular technique is feasible.


1993 ◽  
Vol 56 (12) ◽  
pp. 1043-1050 ◽  
Author(s):  
JOAN B. ROSE ◽  
MARK D. SOBSEY

Human pathogenic viruses have been detected from approved shellfish harvesting waters based on the fecal coliform indicator. Until recently it was difficult to assess viral contamination and the potential impact on public health. Risk assessment is a valuable tool which can be used to estimate adverse effects associated with microbial hazards. This report describes the use of quantitative risk assessment for evaluating potential human health impacts associated with exposure to viral contamination of shellfish. The four fundamental steps used in a formal risk assessment are described within and include i) Hazard identification, ii) Dose-response determination, iii) Exposure assessment, and iv) Risk characterization. Dose-response models developed from human feeding studies were used to evaluate the risk of infection from contaminated shellfish. Of 58 pooled samples, 19% were found to be positive for viruses. Using an echovirus-12 probability model, the individual risk was determined for consumption of 60 g of raw shellfish. Individual risks ranged from 2.2 × 10−4 to 3.5 × 10−2. These data suggest that individuals consuming raw shellfish from approved waters in the United States may have on the average a 1 in 100 chance of becoming infected with an enteric virus. Using the rotavirus model which represents a more infectious virus, the risk rose to 5 in 10. The potential for use of a risk assessment approach for developing priorities and strategies for control of disease is immense. Epidemiological data have demonstrated the significance of shellfish-associated viral disease and, although limited, appropriate virus occurrence data are available. Additional information on virus occurrence and exposure is needed, and then scientific risk assessment can be used to better assure the safety of seafood.


mSphere ◽  
2019 ◽  
Vol 4 (6) ◽  
Author(s):  
Francisco J. Pérez-Rodriguez ◽  
Gael Vieille ◽  
Lara Turin ◽  
Soner Yildiz ◽  
Caroline Tapparel ◽  
...  

ABSTRACT Human astroviruses (HAstV) are among the most common causative agents of viral gastroenteritis, especially in children, and extraintestinal manifestations have also been described. These viruses are transmitted by the fecal-oral route, implying that stool composition and the gut microbiota may impact their ability to remain infectious. For some enteric viruses, individual bacterial envelope components and other polysaccharide-containing molecules, which are abundant in stools, have been shown to enhance capsid stability. However, the role of the complex stool environment and, most importantly, the role of interindividual differences have been poorly studied. We used HAstV as a model to investigate how the stool environment in itself, its interindividual variability, and some specific stool components could affect HAstV stability and infectivity. Using two different HAstV genotypes, we found that stools as a whole modulate astrovirus infectivity not only in an individual-dependent manner but also in a manner that depends on the viral genotype. A virus-protective effect was observed after incubation with various Gram-positive and Gram-negative bacteria as well as with bacterial components, such as lipopolysaccharide and peptidoglycan. These results were further confirmed in human intestinal tissues, a more physiologically relevant system. Astrovirus infectivity was also preserved by mucin, a major component of intestinal mucus. We further confirmed that these components stabilize the viral capsid. These results show that although HAstV benefits from the stabilizing effect of fecal components, the complexity and variability of the stool composition and the multiple potential interactions may explain the interindividual differences in viral transmission observed in real life. IMPORTANCE To ensure transmission, enteric viruses must maintain their infectivity during the various environmental challenges that they face in transit within and between hosts. Increased knowledge of the factors affecting enteric virus survival may help to control their transmission. This study reveals that specific fecal bacterial components preserve classic human astrovirus infectivity by stabilizing viral particles. However, the outcomes of stool-virus interactions are very variable, ranging from protection to a reduction of viral infectivity, depending on the viral genotype and the individual from whom the stool has been collected. We show that the transmissibility of enteric viruses is dependent on the intestinal contents of the infected individual and highlight the complex multiple interactions that could explain the stochastic nature of enteric virus transmission in humans.


2005 ◽  
Vol 86 (10) ◽  
pp. 2799-2806 ◽  
Author(s):  
Vance P. Lochridge ◽  
Kathryn L. Jutila ◽  
Joel W. Graff ◽  
Michele E. Hardy

Noroviruses cause the majority of epidemic outbreaks of acute viral gastroenteritis worldwide. Human norovirus strains do not grow in cell culture, but recent carbohydrate binding, sequence and structural analyses have begun to define functional domains in the norovirus capsid that may be conserved among multiple antigenic types. The purpose of this study was to localize domains and define sequences in the major capsid protein VP1 that are important for cell interactions. Monoclonal antibodies to genogroups GI.1 and GII.2 reference strains Norwalk virus and Snow Mountain virus, respectively, were generated that blocked binding of recombinant virus-like particles to Caco-2 intestinal cells and inhibited haemagglutination. Peptides that mimicked the mAb binding epitopes were selected from a phage-displayed random nonapeptide library. Anti-recombinant Norwalk virus mAb 54.6 and anti-recombinant Snow Mountain virus mAb 61.21 recognized epitopes located in the protruding P2 domain of VP1. The epitope recognized by mAb 61.21 contained amino acids that are completely conserved among norovirus strains across genogroups, including strains isolated from swine, bovine and murine species. This study identifies the first epitope involved in inhibition of norovirus–cell interactions and supports increasing evidence that interactions between noroviruses and host cells rely on structures in the P2 domain of VP1.


Sign in / Sign up

Export Citation Format

Share Document