The heat sensitivity of hepatitis A virus determined by a simple tissue culture method

Parry, J. V.; Mortimer, Philip P.

doi:10.1002/jmv.1890140312

Cited by 76 publications

(40 citation statements)

References 9 publications

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“…In order to evaluate the effects of food matrix composition on thermal inactivation, the levels of resistance of HAV were compared in several food samples. Thermal inactivation studies for HAV have involved cell culture medium, spinach, shellfish, mussels, clams, cockles, and milk; reported D values for HAV in the range of 50 to 100°C were 0.01 to 385 min (26,27,(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50). According to the product description, the composition of the turkey deli meat included sodium (10 mg/g), fat (0.8%), carbohydrates (1.7%), protein (19%), and moisture (77%).…”

Section: Resultsmentioning

confidence: 99%

Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat

Bozkurt

D’Souza

Davidson

2015

Appl Environ Microbiol

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4), in a publication on the incidence and causes of foodborne illnesses in the United States, reported that a large number of outbreaks are caused by HNoV (58%). Additionally, relatively high hospitalization and death rates are associated with HAV infection (32% and 2%, respectively) (1, 4).According to the U.S. Food and Drug Administration (FDA) and U.S. Department of Agriculture Food Safety and Inspection Service (FSIS), deli meat has posed the highest per annum risk of illness and death among poultry products (5). Additionally, in other studies, Gould et al. (6) and Painter et al. (7) studied surveillance and attribution of foodborne disease outbreaks in the United States from 1998 to 2008. They found that, among individual food categories, poultry was the most commonly reported food vehicle of disease, causing 17% of outbreaks of foodborne illness (6), and that the proportions of poultry-associated foodborne illnesses, hospitalizations, and deaths caused by human noroviruses and HAV were 28%, 14%, and 4%, respectively (7). In 1998 through 2002 alone, three large outbreaks were linked to the consumption of turkey delicatessen meat contaminated during processing (7). Since ready-to-eat (RTE) meat and poultry deli products can be consumed without further cooking, these products should be free of non-spore-forming pathogens following the industrial thermal process. However, they can become contaminated before packaging in the final retail wrap and thus pose a safety threat for consumers (8,9). Viral contamination of RTE and prepared foods most frequently comes from poor hand-washing practices of food handlers after toilet use. Fecal material can be left on hands or even under nails which then can come in contact with food products (10). Handling cooked products with bare hands has been identified as a major factor for pathogen transfer to RTE foods (11), and there is presumed to be a direct correlation between the number of pathogenic organisms on a food employee's hands and the probability of microbial transfer from hands to cooked food products (12). Since the contamination most likely occurs at the surface, it seems advisable to decontaminate the outer layer of products. For this purpose, postpackage pasteurization technologies could be practiced as a method for reducing surface contamination by food pathogens (9). One of the challenges for the industry would be to assess the required time and temperature combination, which would depend on the thermal inactivation kinetics of the target microorganism (13). It has been reported that foodborne enteric viruses are more heat resistant than most non-spore-forming bacterial foodborne pathogens (14); thus, processing recommendations based on the data for non-spore-forming bacteria may not eliminate similar numbers of foodborne enteric viruses. Since there is no specific federal regulation covering the minimum time-temperature combinations for inactivating virus in contaminated deli meat, establishment of potential thermal processes for inactivating human norovirus...

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Section: Resultsmentioning

confidence: 99%

Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat

Bozkurt

D’Souza

Davidson

2015

Appl Environ Microbiol

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“…2-log reduction in virus titer, respectively (18). Complete inactivation of HAV was only achieved at 98ЊC for 1 min (11).…”

Section: Discussionmentioning

confidence: 99%

Heat Inactivation of Hepatitis A Virus in Dairy Foods

Bidawid

Farber

Sattar

et al. 2000

Journal of Food Protection

113

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Experiments were performed to determine the thermal resistance of hepatitis A virus (HAV) in three types of dairy products containing increased amounts of fat content (skim milk, homogenized milk; 3.5% MFG, and table cream; 18% MFG). HAV-inoculated dairy products were introduced into custom-made U-shaped microcapillary tubes that in turn were simultaneously immersed in a waterbath, using custom-made floating boats and a carrying platform. Following exposure to the desired time and temperature combinations, the contents of each of the tubes was retrieved and was tested by plaque assay to determine the reduction in virus titer. Our data indicated that Ͻ0.5 min at 85ЊC was sufficient to cause a 5-log reduction in HAV titer in all three dairy products, whereas at 80ЊC, Յ0.68 min (for skim and homogenized milk), and 1.24 min (for cream) were needed to cause a similar log reduction. Using a nonlinear two-phase negative exponential model (two-compartment model) to analyze the data, it was found that at temperatures of 65, 67, 69, 71, and 75ЊC, significantly (P Ͻ 0.05) higher exposure times were needed to achieve a 1-log reduction in virus titer in cream, as compared to skim and homogenized milk. For example, at 71ЊC, a significantly (P Ͻ 0.05) higher exposure time of 0.52 min (for cream) was needed as compared to Յ0.18 min (for skim and homogenized milk) to achieve a 1-log reduction in virus titer. A similar trend of inactivation was observed at 73 and 75ЊC where significantly (P Ͻ 0.05) higher exposure times of 0.29 to 0.36 min for cream were needed to cause a 1-log reduction in HAV in cream, as compared to Յ0.17 min for skim and homogenized milk. This study has provided information on the heat resistance of HAV in skim milk, homogenized milk, and table cream and demonstrated that an increase in fat content appears to play a protective role and contributes to the heat stability of HAV.Hepatitis A virus (HAV), the causative agent of hepatitis A, is a member of the Picornaviridae family. Because of its unique genetic and physical characteristics, HAV has now been assigned to a distinct genus, hepatovirus (17). It is a 27-nm icosahedral, nonenveloped virus, containing a 7.5-kb positive-stranded RNA genome that is enclosed by a capsid protein shell consisting of VP1, VP2, VP3, and VP4 glycoproteins. Despite its successful propagation in cell culture (3,19), wild-type HAV strains are still very difficult to culture, even in primary mammalian cells. Although similar to other enteroviruses in morphology and composition, HAV exhibits greater resistance to inactivation by various chemical and physical agents, including heat (4,6,8,21). Outbreaks of foodborne hepatitis have been well documented epidemiologically with a wide variety of foods, such as shellfish, salads, fruits, and dairy products being implicated (1,2,20). Most investigations have focused on the use of heat as a method of inactivating HAV in shellfish. Koff and Sear (10) indicated that it took 4 to 6 min for the internal temperature to reach 100ЊC in st...

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“…Frosner (1982) (1952) demonstrated that ice cream, cream and milk can exert protective effects on poliovirus when exposed to heat. Parry & Mortimer (1984) found that the stability of HAV was increased when suspended in milk. The steaming or immersion in boiling water of shellfish such as cockles is intended to render them safe for the consumer.…”

Section: Discussionmentioning

confidence: 99%

Studies on heat inactivation of hepatitis A virus with special reference to shellfish: Part 1. Procedures for infection and recovery of virus from laboratory-maintained cockles

1987

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SUMMARYThe consumption of bi-valve molluscan shellfish has been associated with outbreaks of viral gastroenteritis and hepatitis A. Investigations were undertaken to determine the heat inactivation conditions necessary to render shellfish such as cockles safe for the consumer. Conditions for the laboratory maintenance of live cockles are described. In preliminary experiments either poliovirus (106 TCID50/ml seawater) or hepatitis A virus (HAV) (approx. 104 RFU/ml seawater) was introduced into the shellfish tank. Following 48 h filter feeding, virus was recovered from cockles using an adsorption-elution extraction procedure. Titres of virus recovered ranged from 104 to 105 TCID50/ml of shellfish extract for poliovirus and from 103 to 105 RFU/ml of shellfish extract for HAV. Active ingestion of the virus from the seawater was demonstrated by recovering virus from within cockle guts.To quantify recovered HAV, end-point dilutions and an adaptation of a radioimmunofocus assay (RIFA) were compared. The tests were of similar sensitivity but the RIFA has the advantage of being relatively rapid, shortening the time taken to complete an experiment by as much as 4 weeks.

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The heat sensitivity of hepatitis A virus determined by a simple tissue culture method

Cited by 76 publications

References 9 publications

Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat

Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat

Heat Inactivation of Hepatitis A Virus in Dairy Foods

Studies on heat inactivation of hepatitis A virus with special reference to shellfish: Part 1. Procedures for infection and recovery of virus from laboratory-maintained cockles

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