scholarly journals Temperature-Dependent Survival of Hepatitis A Virus during Storage of Contaminated Onions

2012 ◽  
Vol 78 (14) ◽  
pp. 4976-4983 ◽  
Author(s):  
Y. Sun ◽  
D. T. Laird ◽  
Y. C. Shieh

ABSTRACTPre- or postharvest contamination of green onions by hepatitis A virus (HAV) has been linked to large numbers of food-borne illnesses. Understanding HAV survival in onions would assist in projecting the risk of the disease associated with their consumption. This study defined HAV inactivation rates in contaminated green onions contained in air-permeable, moisture-retaining high-density polyethylene packages that were stored at 3, 10, 14, 20, 21, 22, and 23°C. A protocol was established to recover HAV from whole green onions, with 31% as the average recovery by infectivity assay. Viruses in eluates were primarily analyzed by a 6-well plaque assay on FRhK-4 cells. Eight storage trials, including two trials at 3°C, were conducted, with 3 to 7 onion samples per sampling and 4 to 7 samplings per trial. Linear regression correlation (r2= 0.80 to 0.98) was observed between HAV survival and storage time for each of the 8 trials, held at specific temperatures. Increases in the storage temperature resulted in greater HAV inactivation rates, e.g., a reduction of 0.033 log PFU/day at 3.4 ± 0.3°C versus 0.185 log PFU/day at 23.4 ± 0.7°C. Thus, decimal reduction time (D) values of 30, 14, 11, and 5 days, respectively, were obtained for HAV in onions stored at 3, 10, 14, and 23°C. Further regression analysis determined that 1 degree Celsius increase would increase inactivation of HAV by 0.007 log PFU/day in onions (r2= 0.97). The data suggest that natural degradation of HAV in contaminated fresh produce is minimal and that a preventive strategy is critical to produce safety. The results are useful in predicting the risks associated with HAV contamination in fresh produce.

2000 ◽  
Vol 66 (7) ◽  
pp. 2759-2763 ◽  
Author(s):  
S. Bidawid ◽  
J. M. Farber ◽  
S. A. Sattar

ABSTRACT Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm2resulted in transfer of 9.2% � 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% � 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.


2009 ◽  
Vol 72 (11) ◽  
pp. 2390-2393 ◽  
Author(s):  
Y. CAROL SHIEH ◽  
DIANA S. STEWART ◽  
DAVID T. LAIRD

Spinach leaves are frequently consumed raw and have been involved with past foodborne outbreaks. In this study, we examined the survival of hepatitis A virus (HAV) on fresh spinach leaves in moisture- and gas-permeable packages that were stored at 5.4 ± 1.2°C for up to 42 days. Different eluents including phosphate-buffered saline (PBS), pH 7.5 (with and without 2% serum), and 3% beef extract (pH 7.5 and 8) were compared for how efficiently they recovered viruses from spinach by using a simple elution procedure (<1 h). The recoveries were compared and determined by a plaque assay with FRhK-4 cells. Culture grade PBS containing 2% serum was found to be appropriate for HAV elution from spinach leaves, with an average recovery of 45% ± 10%. Over 4 weeks of storage at 5.4 ± 1.2°C, HAV in spinach decreased slightly more than 1 log, with 6.75% of the original titer remaining. HAV survived under refrigerated temperatures on spinach leaves with a D-value of 28.6 days (equivalent to an inactivation rate of 20.035 log of HAV per day, r2 = 0.88). In comparison, HAV in PBS containing 2% serum under the same storage conditions remained constant throughout 7 weeks. The inactivation rate of 20.035 log each day for HAV on spinach leaves was possibly due to the interaction of the virus and the leaf.


2015 ◽  
Vol 81 (14) ◽  
pp. 4850-4859 ◽  
Author(s):  
Hayriye Bozkurt ◽  
Doris H. D'Souza ◽  
P. Michael Davidson

ABSTRACTHuman noroviruses (HNoV) and hepatitis A virus (HAV) have been implicated in outbreaks linked to the consumption of presliced ready-to-eat deli meats. The objectives of this research were to determine the thermal inactivation kinetics of HNoV surrogates (murine norovirus 1 [MNV-1] and feline calicivirus strain F9 [FCV-F9]) and HAV in turkey deli meat, compare first-order and Weibull models to describe the data, and calculate Arrhenius activation energy values for each model. TheD(decimal reduction time) values in the temperature range of 50 to 72°C calculated from the first-order model were 0.1 ± 0.0 to 9.9 ± 3.9 min for FCV-F9, 0.2 ± 0.0 to 21.0 ± 0.8 min for MNV-1, and 1.0 ± 0.1 to 42.0 ± 5.6 min for HAV. Using the Weibull model, thetD = 1(time to destroy 1 log) values for FCV-F9, MNV-1, and HAV at the same temperatures ranged from 0.1 ± 0.0 to 11.9 ± 5.1 min, from 0.3 ± 0.1 to 17.8 ± 1.8 min, and from 0.6 ± 0.3 to 25.9 ± 3.7 min, respectively. Thez(thermal resistance) values for FCV-F9, MNV-1, and HAV were 11.3 ± 2.1°C, 11.0 ± 1.6°C, and 13.4 ± 2.6°C, respectively, using the Weibull model. Thezvalues using the first-order model were 11.9 ± 1.0°C, 10.9 ± 1.3°C, and 12.8 ± 1.7°C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 214 ± 28, 242 ± 36, and 154 ± 19 kJ/mole, respectively, while the calculated activation energies for the first-order model were 181 ± 16, 196 ± 5, and 167 ± 9 kJ/mole, respectively. Precise information on the thermal inactivation of HNoV surrogates and HAV in turkey deli meat was generated. This provided calculations of parameters for more-reliable thermal processes to inactivate viruses in contaminated presliced ready-to-eat deli meats and thus to reduce the risk of foodborne illness outbreaks.


1987 ◽  
Vol 22 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Theresa Cromeans ◽  
Mark D. Sobsey ◽  
Howard A. Fields

2000 ◽  
Vol 66 (1) ◽  
pp. 213-218 ◽  
Author(s):  
Kellogg J. Schwab ◽  
Frederick H. Neill ◽  
Rebecca L. Fankhauser ◽  
Nicholas A. Daniels ◽  
Stephan S. Monroe ◽  
...  

ABSTRACT “Norwalk-like viruses” (NLVs) and hepatitis A virus (HAV) are the most common causes of virus-mediated food-borne illness. Epidemiological investigations of outbreaks associated with these viruses have been hindered by the lack of available methods for the detection of NLVs and HAV in foodstuffs. Although reverse transcription (RT)-PCR methods have been useful in detecting NLVs and HAV in bivalve mollusks implicated in outbreaks, to date such methods have not been available for other foods. To address this need, we developed a method to detect NLVs and HAV recovered from food samples. The method involves washing of food samples with a guanidinium-phenol-based reagent, extraction with chloroform, and precipitation in isopropanol. Recovered viral RNA is amplified with HAV- or NLV-specific primers in RT-PCRs, using a viral RNA internal standard control to identify potential sample inhibition. By this method, 10 to 100 PCR units (estimated to be equivalent to 102 to 103 viral genome copies) of HAV and Norwalk virus seeded onto ham, turkey, and roast beef were detected. The method was applied to food samples implicated in an NLV-associated outbreak at a university cafeteria. Sliced deli ham was positive for a genogroup II NLV as determined by using both polymerase- and capsid-specific primers and probes. Sequence analysis of the PCR-amplified capsid region of the genome indicated that the sequence was identical to the sequence from virus detected in the stools of ill students. The developed method is rapid, simple, and efficient.


2020 ◽  
Vol 83 (9) ◽  
pp. 1576-1583
Author(s):  
CHRISTINE YU ◽  
KAORU HIDA ◽  
EFSTATHIA PAPAFRAGKOU ◽  
MICHAEL KULKA

ABSTRACT Foodborne viral contamination of fresh produce has been associated with numerous outbreaks. Detection of such contaminated foods is important in protecting public health. Here, we demonstrate for the first time the capability of the U.S. Food and Drug Administration Enteric Viruses tiling microarray (FDA-EVIR) to perform rapid molecular identification of hepatitis A virus (HAV) and human norovirus extracted from artificially inoculated fresh produce. Two published viral extraction strategies, total RNA extraction or virus particle isolation, were used to prepare the viral targets. The total RNA extraction method was used on material eluted from tomatoes, using an alkaline Tris–glycine–beef extract (TGBE) buffer. Optimization procedures including DNase treatment and poly(A)-RNA enrichment were adopted to improve microarray sensitivity. For green onions or celery, material was eluted using either glycine buffer or TGBE buffer supplemented with pectinase, respectively, and then virus particles were concentrated by ultracentrifugation. We also assessed the amount of viral RNA extracted from celery using three commercially available kits and how well that RNA performed on FDA-EVIR. Our results confirm that FDA-EVIR can identify common enteric viruses isolated from fresh produce when present as either a single or mixed species of viruses. Using total RNA extraction from tomatoes yielded a limit of detection of 1.0 × 105 genome equivalents (ge) of HAV per array input. The limit of detection for viral RNA obtained using ultracentrifugation was 1.2 × 105 ge of HAV from green onions and 1.0 × 103 ge of norovirus from celery per array input. Extending microarray methods to other food matrices should provide important support to surveillance and outbreak investigations. HIGHLIGHTS


1991 ◽  
Vol 24 (2) ◽  
pp. 229-234 ◽  
Author(s):  
A. Bosch ◽  
R. Gajardo ◽  
F. X. Abad ◽  
J. M. Diez ◽  
J. Jofre

The cytopathogenic pHM-175 strain of hepatitis A virus was used to develop different procedures for the concentration of HAV in tap water, fresh water, seawater and raw sewage, HAV was quantified by a plaque assay in the FRhK-4 cell line. Water samples were concentrated by a modification of the adsorption to and elution from glass powder (GPAE) method, by adsorption to and elution from filter aid, and by ammonium sulfate flocculation (ASF). The GPAE method consistently yielded greater HAV recoveries than filtration through filter aid, or ASF. HAV was concentrated by GPAE from 20-litre samples with satisfactory efficiencies in all kinds of water: 100% for tap water, 80% for freshwater, 75% for seawater and 61% for sewage. Concentration efficiencies for filter aid and ASF were always lower than 25% and 40%, respectively, in any kind of water. The charge of glass powder was modified by polyethylenimine treatment. Concentration efficiencies of HAV in 20 1 samples through adsorption to and elution from positively charged glass powder (PGPAE) were 100% for tap water, 94% for seawater, and 61% for freshwater and sewage. The presence of wild-type HAV in sewage samples could be monitored by molecular hybridization with cDNA probes after GPAE concentration.


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