scholarly journals Chlorine inactivation of coliphage MS2 on strawberries by industrial-scale water washing units

2009 ◽  
Vol 7 (2) ◽  
pp. 244-250 ◽  
Author(s):  
Michael J. Casteel ◽  
Charles E. Schmidt ◽  
Mark D. Sobsey
Keyword(s):  
Hepatitis A ◽  
Fruits And Vegetables ◽  
Hepatitis A Virus ◽  
Field Studies ◽  
Wash Water ◽  
Industrial Scale ◽  
Cross Contamination ◽  
Minimal Processing ◽  
Water Washing ◽  
Pathogenic Viruses

Fruits and vegetables (produce) intended for minimal processing are often rinsed or washed in water. Chlorine and other sanitizers are used during washing to inactivate produce spoilage microbes, but such procedures may also inactivate pathogens epidemiologically linked to produce, such as hepatitis A virus (HAV). However, no information exists on the efficacy of chlorinated wash water to inactivate HAV and other viruses on produce in actual practice, because of obvious safety concerns. In contrast, coliphage MS2 (a bacterial virus) is commonly used as a surrogate for some pathogenic viruses and may be safely used in field studies. In the present investigation, strawberries seeded with MS2 were passed through industrial-scale water washing units operated with or without added sodium hypochlorite. MS2 on strawberries was inactivated by 68%, 92% and 96% at free chlorine (FC) concentrations of ≤2, 20 and 200 ppm in wash water, respectively. MS2 was detected in wash water containing ≤2 ppm FC in one trial, but was not detected in water containing 20 or 200 ppm FC. The presence and absence of MS2 in wash water containing various levels of FC highlight the importance of controlling sanitizer levels to prevent viral cross contamination of strawberries.

Survival of Hepatitis A Virus on Two-month Stored Freeze-dried Berries

2021 ◽  
Author(s):  
Yan Zhang ◽  
Xueyan Wang ◽  
Y. Carol Shieh
Keyword(s):  
Freeze Drying ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Reduction Rate ◽  
Radiant Heating ◽  
Minimal Processing ◽  
Log Reduction ◽  
C Storage ◽  
Freeze Dried ◽  
Heating Up

Imported berries have contributed to U.S. hepatitis A virus (HAV) infections. Minimal processing by freeze-drying is preferred by industry for preserving food quality, but virus inactivation by this process may be limited. This study investigated HAV survival on strawberries during 24-h freeze-drying followed by 22 ° C-storage. The outer surfaces of strawberry slices were prepared and each inoculated with 5 to 6 log 10 PFU HAV, air-dried 20 min, frozen 1 h at -80 °C, and freeze-dried 24 h with radiant heating up to 36 °C. Infectious HAV levels eluted from berry slices were quantified on FRhK-4 cells grown onto 6-well dishes. Freeze-drying trials (n = 17) with radiant heating inactivated ≤1 log 10 PFU per trial, although HAV-inactivation was significantly greater at 36 ºC than 15 ºC heating ( p < 0.01). Average HAV reduction rate on dried berries continuously decreased as storage time increased, 0.2, 0.09, 0.08, 0.04, 0.04 and 0.03 log-reduction/day at day 2, 7, 14, 28, 42, and 56, respectively, with the cumulated log-reduction divided by storage days. Therefore, the best fit regression for the total/cumulative virus reduction (Y) at any given day (X) is Y= 0.2882X 0.4503 (r² = 0.97), with maximum 2.7 log-reduction on berries throughout the drying and subsequent 2-month storage. HAV showed the greatest decline within the first 14-days of storage of dried berries (approximately 70% weekly reduction from its previous week levels), but the HAV reduction rates were still lower than that occurring on fresh produce.

Outbreaks of Shellfish-Associated Enteric Virus Illness in the United States: Requisite for Development of Viral Guidelines

1985 ◽  
Vol 48 (9) ◽  
pp. 815-823 ◽  
Author(s):  
GARY P. RICHARDS
Keyword(s):  
United States ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Enteric Virus ◽  
The United States ◽  
Viral Gastroenteritis ◽  
Norwalk Virus ◽  
Virus Contamination ◽  
Pathogenic Viruses

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.

UV Light Inactivation of Hepatitis A Virus, Aichi Virus, and Feline Calicivirus on Strawberries, Green Onions, and Lettuce

2008 ◽  
Vol 71 (5) ◽  
pp. 908-913 ◽  
Author(s):  
VIVIANA R. FINO ◽  
KALMIA E. KNIEL
Keyword(s):  
Foodborne Pathogens ◽  
Hepatitis A ◽  
Fruits And Vegetables ◽  
Hepatitis A Virus ◽  
Uv Light ◽  
Mammalian Cell Culture ◽  
Aichi Virus ◽  
Feline Calicivirus ◽  
Virus Inactivation ◽  
Need To Evaluate

A majority of illnesses caused by foodborne viruses are associated with fresh produce. Fruits and vegetables may be considered high-risk foods, as they are often consumed raw without a specific inactivation step. Therefore, there is a need to evaluate nonthermal treatments for the inactivation of foodborne pathogens. This study investigates the UV inactivation of three viruses: feline calicivirus (a surrogate for norovirus), and two picornaviruses, hepatitis A virus and Aichi virus. Three produce types were selected for their different surface topographies and association with outbreaks. Green onions, lettuce, and strawberries were individually spot inoculated with 107 to 109 50% tissue culture infective doses (TCID50) of each virus per ml and exposed to UV light at various doses (≤240 mW s/cm2), and viruses were eluted using an optimized recovery strategy. Virus infection was quantified by TCID50 in mammalian cell culture and compared with untreated recovered virus. UV light applied to contaminated lettuce resulted in inactivation of 4.5 to 4.6 log TCID50/ml; for contaminated green onions, inactivation ranged from 2.5 to 5.6 log TCID50/ml; and for contaminated strawberries, inactivation ranged from 1.9 to 2.6 log TCID50/ml for the three viruses tested. UV light inactivation on the surface of lettuce is more effective than inactivation on the other two produce items. Consistently, the lowest results were observed in the inactivation of viruses on strawberries. No significant differences (P > 0.05) for virus inactivation were observed among the three doses applied (40, 120, and 240 mW s/cm2)on the produce, with the exception of hepatitis A virus and Aichi virus inactivation on green onions, where inactivation continued at 120 mW s/cm2 (P < 0.05).

Removal of hepatitis a virus (HAV), poliovirus and MS2 coliphage by coagulation and high rate filtration

1995 ◽  
Vol 31 (5-6) ◽  
pp. 63-68 ◽  
Author(s):  
A. Nasser ◽  
D. Weinberg ◽  
N. Dinoor ◽  
B. Fattal ◽  
A. Adin
Keyword(s):  
Humic Acid ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Cationic Polyelectrolyte ◽  
High Rate ◽  
Sand Column ◽  
Virus Removal ◽  
Jar Test ◽  
Pathogenic Viruses ◽  
Operation Unit

Filtration is considered a mandatory operation unit for the production of pathogen free drinking water from surface sources. This study was undertaken to determine the removal efficiency of enteric pathogenic viruses (hepatitis A virus and poliovirus) by high rate filtration and to determine the suitability of F+bacteriophages as index for the removal of these pathogens. A jar test was used to determine the optimal flocculation dose to be used in the high rate filtration experiments. At an alum concentration of 30 mg/l, the greatest reduction was observed for HAV (88.4%) as compared with poliovirus 1 (47%) and turbidity (61%). Addition of 1 mg/l cationic polyelectrolyte improved the reduction of HAV to 98.3% by flocculation, while the removal of polio 1 and turbidity was not improved. The presence of humic acid at a concentration of 15.3 mg/l interfered with flocculation performance of HAV and turbidity, while the addition of the cationic polyelectrolyte reduced the interference appreciably. High rate filtration (20 m/hr) using a 100 cm long sand column, resulted in reduction of 99%, 93% and 80% of turbidity, MS2 and poliovirus 1, respectively. Addition of polyelectrolyte enhanced the removal of viruses and turbidity. In the presence of humic acid no virus removal was observed by high rate filtration, whereas turbidity removal was unaffected. The removal of MS2 was similar to that of HAV rather than poliovirus 1. High rate filtration was found efficient for the removal of pathogenic viruses and turbidity from surface water. Under all conditions tested the removal of turbidity was greater than that of viruses.

scholarly journals Foodborne Pread of Hepatitis A: Recent Studies on Virus Survival, Transfer and Inactivation

2000 ◽  
Vol 11 (3) ◽  
pp. 159-163 ◽  
Author(s):  
Syed A Sattar ◽  
Jason Tetro ◽  
Sabah Bidawid ◽  
Jeff Farber
Keyword(s):  
Hepatitis A ◽  
Fruits And Vegetables ◽  
Hepatitis A Virus ◽  
Food Service ◽  
Disease Outbreaks ◽  
Economic Losses ◽  
Viral Pathogen ◽  
Environmental Surfaces ◽  
Considerable Morbidity ◽  
Virus Survival

Hepatitis A virus (HAV) is responsible for considerable morbidity and economic losses worldwide, and is the only reportable, foodborne viral pathogen in Canada. Outbreaks caused by it occur more frequently in settings such as hospitals, daycare centres, schools, and in association with foods and food service establishments. In recent years, the incidence of hepatitis A has increased in Canada. Many factors, including changing lifestyles and demographics, faster and more frequent travel, and enhanced importation of foods from hepatitis A-endemic regions, may be behind this increase. Despite its increasing significance as a human pathogen, not much was known until recently about the survival and inactivation of HAV, and even less was understood about the effectiveness of measures to prevent and control its foodborne spread. Studies conducted in the past decade have shown that HAV can survive for several hours on human hands and for several days on environmental surfaces indoors. The virus can also retain its infectivity for several days on fruits and vegetables which are often consumed raw, and such imported items have already been incriminated in disease outbreaks. Casual contact between contaminated hands and clean food items can readily lead to a transfer of as much as 10% of the infectious virus. HAV is also relatively resistant to inactivation by heat, gamma irradiation and chemical germicides. In view of these findings, better approaches to prevent the contamination of foods with HAV and more effective methods for its inactivation in foods, on environmental surfaces and on the hands of food handlers are needed.

Viruses in Mussels: Public Health Implications and Depuration

1997 ◽  
Vol 60 (6) ◽  
pp. 677-681 ◽  
Author(s):  
F. XAVIER ABAD ◽  
ROSA M. PINTÓ ◽  
RODRIGO GAJARDO ◽  
ALBERT BOSCH
Keyword(s):  
Public Health ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Enteric Viruses ◽  
Adenovirus Type ◽  
Marine Water ◽  
Health Implications ◽  
Public Consumption ◽  
Enteric Adenovirus ◽  
Pathogenic Viruses

Studies were conducted in the common mussel (Mytilus spp.) to evaluate the public health implications derived from shellfish contamination with human pathogenic enteric viruses. In bioaccumulation experiments, we could verify that after 6 h of immersion of mussels in marine water contaminated with high levels of clay-associated enteric adenovirus (type 40) and human rotavirus (type 3), between 4 to 56% of the seeded viruses were adsorbed to shellfish tissues, mainly in the gills and digestive tract. We investigated the occurrence of wild-type enteric viruses in mussels from sites with different levels of fecal pollution. Pathogenic viruses could be detected in mussels from areas that, following current standards based on bacteriological quality, should be regarded as unpolluted, safe for swimming, and suitable for harvesting shellfish. Cooking experiments performed with contaminated mussels revealed that 5 min after the opening of the mussel valves, rotaviruses and hepatitis A virus could still be recovered in steamed shellfish. Under commercial depuration conditions, health-significant enteric viruses, such as rotavirus and hepatitis A virus, could be recovered from bivalves after 96 h of immersion in a continuous flow of ozonated marine water. Routine screening of bivalves for the presence of health-significant enteric viruses before public consumption may help in the prevention of outbreaks among shellfish consumers.

scholarly journals Detection of Pathogenic Viruses in Sewage Provided Early Warnings of Hepatitis A Virus and Norovirus Outbreaks

2014 ◽  
Vol 80 (21) ◽  
pp. 6771-6781 ◽  
Author(s):  
Maria Hellmér ◽  
Nicklas Paxéus ◽  
Lars Magnius ◽  
Lucica Enache ◽  
Birgitta Arnholm ◽  
...  
Keyword(s):  
Early Warning ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Milk Proteins ◽  
Hepatitis E ◽  
Aichi Virus ◽  
Untreated Sewage ◽  
Before And After ◽  
Pathogenic Viruses ◽  
Different Strains

ABSTRACTMost persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care.

Physical Removal and Transfer of Murine Norovirus and Hepatitis A Virus from Contaminated Produce by Scrubbing and Peeling

2013 ◽  
Vol 76 (1) ◽  
pp. 85-92 ◽  
Author(s):  
QING WANG ◽  
MARILYN C. ERICKSON ◽  
YNES ORTEGA ◽  
JENNIFER L. CANNON
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Virus Detection ◽  
Cross Contamination ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Running Water ◽  
Virus Removal ◽  
Food Residue ◽  
Virus Transfer

Human noroviruses and hepatitis A virus are responsible for numerous outbreaks associated with handling fresh produce. In this study, physical removal of hepatitis A virus and murine norovirus, a human norovirus surrogate, from contaminated produce items (honeydew melons, cantaloupes, carrots, and celery) by scrubbing under running water with a nylon brush or scouring pad and by peeling (carrots and celery) with a peeler was investigated. The degree and extent of utensil contamination with viruses during these operations in the presence and absence of food residue also was investigated. Scrubbing or peeling produce initially inoculated with ~5.5 log PFU of each virus resulted in significant levels of virus removal, ranging from 0.93 to 2.85 log PFU. However, utensil cross-contamination occurred, with >2 log PFU of virus transferred from a single produce item. After preparation of a contaminated produce item, utensil cross-contamination resulted in virus detection on seven successively prepared produce items. Produce residue accumulation on utensils variably impacted virus transfer to utensil surfaces. Results indicate that scrubbing and peeling produce can reduce levels of viruses on contaminated produce, but the importance of utensil sanitation to prevent cross-contamination is highlighted. Findings also provide important information for modeling virus cross-contamination during food preparation.

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