Experimental and CFD evaluation of ozone efficacy against coronavirus and enteric virus contamination on public transport surfaces

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.

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

Journal of Food Protection ◽

10.4315/0362-028x-44.4.294 ◽

1981 ◽

Vol 44 (4) ◽

pp. 294-296 ◽

Cited By ~ 13

Author(s):

M. J. EYLES ◽

G. R. DAVEY ◽

E. J. HUNTLEY

Keyword(s):

Causative Agent ◽

Enteric Virus ◽

Fecal Specimen ◽

Viral Gastroenteritis ◽

Norwalk Virus ◽

Viral Contamination ◽

Virus Contamination ◽

Human Enteric Virus ◽

Viral Illness ◽

Echovirus Type

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.

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Microbial Purification of Shellfish: A Review of Depuration and Relaying

Journal of Food Protection ◽

10.4315/0362-028x-51.3.218 ◽

1988 ◽

Vol 51 (3) ◽

pp. 218-251 ◽

Cited By ~ 109

Author(s):

GARY P. RICHARDS

Keyword(s):

Enteric Virus ◽

Intestinal Cells ◽

Review Of The Literature ◽

Indicator Microorganisms ◽

Virus Contamination ◽

Pathogenic Viruses ◽

Proper Design ◽

Flow Through ◽

Low Levels ◽

Vibrio Spp

A review of the literature on shellfish depuration and relaying revealed wide diversity in microbial uptake and elimination among shellfish species and for different microorganisms. Information on relaying of five commercial shellfish species and on controlled purification (depuration) of 11 species indicates that such processes are effective in reducing the levels of bioconcentrated bacteria and viruses from shellfish. The degree of bacterial and viral bioconcentration varies with shellfish species; however, the primary sites of bioconcentration are the hepatopancreas and digestive diverticula. Low levels of enteric viruses and coliphage may be sequestered in shellfish hemolymph and tissues, thus protecting them from elimination through depurative processes. Vibrio spp. appear to proliferate when closely associated with intestinal cells of shellfish. Shellfish relaying techniques offer effective microbial depletion provided water quality is acceptable and shellfish remain physiologically active. The current body of literature on controlled purification demonstrates a broad spectrum of conditions under which shellfish are depurated. Optimal times, temperatures and salinities for effective depuration vary among shellfish species. Proper design and operation of depuration plants is crucial to insure process integrity. Recirculating and flow-through purification systems are effective in reducing the levels of pathogenic and indicator microorganisms from shellfish, but the extent to which they reduce viruses from shellfish is uncertain. Studies are needed to validate the effectiveness of depuration processes in eliminating pathogenic viruses and to address the adequacy of indicator bacteria as measures of enteric virus contamination.

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Bacteriophages and bacteria as indicators of enteric viruses in oysters and their harvest waters

Water Science & Technology ◽

10.2166/wst.1998.0494 ◽

1998 ◽

Vol 38 (12) ◽

pp. 37-44 ◽

Cited By ~ 18

Author(s):

H. Chung ◽

L.-A. Jaykus ◽

G. Lovelace ◽

M. D. Sobsey

Keyword(s):

Enteric Viruses ◽

Enteric Virus ◽

Indicator Bacteria ◽

Faecal Coliforms ◽

Rt Pcr ◽

E Coli ◽

Virus Contamination ◽

Receiving Waters ◽

Male Specific ◽

Receiving Water

Reliable indicators are needed to detect enteric virus contamination of bivalve molluscan shellfish and their harvest waters. Concentrations of male-specific (F+) coliphages, Bacteroides fragilis phages, Salmonella phages and several indicator bacteria in wastewater, estuarine receiving water and its oysters were examined for their ability to predict the presence and levels of faecal contamination and enteric viruses in oysters. Enteric viruses in oysters were detected by cell culture and RT-PCR methods. F+ coliphages, Salmonella phages, B fragilis phages and faecal indicator bacteria (faecal coliforms, E coli, enterococci and Clostridium perfringens) were generally positively associated and were highest in raw sewage and progressively lower in sewage effluent and in receiving waters at increasing distance from the wastewater discharge. Indicator levels in oysters were highest for F+ coliphages and C perfringens. One F+ RNA coliphage serotype (Group II) predominated in the wastewater, receiving water and oysters. Human enteric viruses were detected in 17/31 oyster samples. The levels of most indicators in oysters and water were higher when oysters were enteric virus-positive and lower when oysters were enteric virus-negative. F+ coliphages and C perfringens were the only indicators significantly associated with the presence of enteric viruses in oysters. F+ coliphages and their serotypes are promising indicators of human enteric virus contamination in oysters and their harvest waters.

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Occurrence of norovirus and other enteric viruses in untreated groundwaters of Korea

Journal of Water and Health ◽

10.2166/wh.2011.142 ◽

2011 ◽

Vol 9 (3) ◽

pp. 544-555 ◽

Cited By ~ 25

Author(s):

Ji Hee Jung ◽

Chang Hoon Yoo ◽

Eung Seo Koo ◽

Hak Min Kim ◽

Youjin Na ◽

...

Keyword(s):

Hepatitis A ◽

Heterotrophic Bacteria ◽

Hepatitis A Virus ◽

Enteric Virus ◽

Additional Treatment ◽

Total Coliforms ◽

E Coli ◽

Virus Contamination ◽

Three Samples ◽

Groundwater Wells

A total of 39 water samples from 23 different groundwater wells in Korea were collected and analyzed in order to monitor the occurrence of norovirus (NoV) and other indicator microbes as the first part of a national survey of groundwater. More than 500 L of untreated groundwater were filtered through 1MDS filters. Following elution and concentration by organic flocculation, PCR and sequence analysis were employed to detect and identify NoV, enterovirus, rotavirus, hepatitis A virus and adenovirus (Adv). Somatic and F-specific phages, heterotrophic bacteria, total coliforms and Escherichia coli were also analyzed to infer possible fecal contamination. NoVs were detected in 18% of the 39 samples. Five out of seven NoV-positive samples (71%) were identified as GI while the other two (29%) were GII. Enteroviruses and Advs were detected in two and three samples, respectively. Rotavirus and hepatitis A virus were not detected. Total coliforms, E. coli and coliphages were detected in 49, 15 and 13% of the samples, respectively, but did not appear to be suitable indicators of enteric virus contamination in groundwater. These results suggest that additional treatment may be needed for a significant number of groundwaters prior to use as drinking water.

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A longitudinal study on enteric virus contamination in bivalves along the coast of Ibaraki Prefecture, Japan

Journal of Food Protection ◽

10.4315/jfp-20-353 ◽

2021 ◽

Author(s):

Takumi Motoya ◽

Noriko Nagata ◽

Ryo Kashimura ◽

Keiko Ohashi ◽

Aoi Saito ◽

...

Keyword(s):

Infectious Disease ◽

Longitudinal Study ◽

Food Poisoning ◽

Enteric Viruses ◽

Enteric Virus ◽

Surrounding Area ◽

Virus Surveillance ◽

Virus Contamination ◽

Harvest Timing ◽

Ibaraki Prefecture

During the 2014–2018 seasons, we conducted a longitudinal study involving enteric virus surveillance in bivalves, including natural oysters and clams harvested in Ibaraki Prefecture, Japan. Some norovirus (NoV) contaminations were detected in natural oysters, while no enteric virus was found in clams. NoV detected in oysters were of the genotypes GII.4 and GII.6, which are closely related genetically to the NoV strains prevalent in humans. We found low level of enteric virus contamination in bivalves collected along the coast of Ibaraki Prefecture. The possibility of food poisoning caused by these viruses appears low, and few cases of infectious disease have been observed in the surrounding area. The harvest timing was more related to detection of enteric viruses than the harvest area. Our results highlighted the fact that contamination of bivalves by enteric viruses may depend upon the prevalence of human diarrhea and illness.

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Round-Robin Comparison of Methods for the Detection of Human Enteric Viruses in Lettuce

Journal of Food Protection ◽

10.4315/0362-028x-67.10.2315 ◽

2004 ◽

Vol 67 (10) ◽

pp. 2315-2319 ◽

Cited By ~ 35

Author(s):

FRANÇOISE S. LE GUYADER ◽

ANNA-CHARLOTTE SCHULTZ ◽

LARISSA HAUGARREAU ◽

LUCIANA CROCI ◽

LEENA MAUNULA ◽

...

Keyword(s):

Low Cost ◽

Enteric Virus ◽

Virus Contamination ◽

Human Enteric Virus ◽

Sewage Contamination ◽

Concentration Step ◽

Human Enteric Viruses ◽

Reliable Methods ◽

Virus Strains ◽

Commercial Kit

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.

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