scholarly journals Chlorine inactivation of hepatitis E virus and human adenovirus 2 in water

2014 ◽  
Vol 12 (3) ◽  
pp. 436-442 ◽  
Author(s):  
Rosina Girones ◽  
Anna Carratalà ◽  
Byron Calgua ◽  
Miquel Calvo ◽  
Jesús Rodriguez-Manzano ◽  
...  
Keyword(s):  
Hepatitis E Virus ◽  
Free Water ◽  
Human Adenovirus ◽  
Hepatitis E ◽  
Oral Route ◽  
Inactivation Kinetics ◽  
Common Source ◽  
Log Reduction ◽  
Chlorine Disinfection ◽  
Kinetics Of

Hepatitis E virus (HEV) is transmitted via the fecal–oral route and has been recognized as a common source of large waterborne outbreaks involving contaminated water in developing countries. Thus, there is the need to produce experimental data on the disinfection kinetics of HEV by chlorine in water samples with diverse levels of fecal contamination. Here, the inactivation of HEV and human adenovirus C serotype 2 (HAdV2), used as a reference virus, was monitored using immunofluorescence and quantitative reverse transcription polymerase chain reaction (RT-qPCR) assays. HEV has been shown to be susceptible to chlorine disinfection and presented equivalent kinetics to human adenoviruses. The C(t) values observed for a 2-log reduction of HEV were 0.41 in buffered demand-free water and 11.21 mg/L × min in the presence of 1% sewage. The results indicate that the inactivation kinetics of HEV and HAdV2 are equivalent and support the use of chlorine disinfection as an effective strategy to control HEV waterborne transmission.

scholarly journals Development and Optimization of an Enzyme Immunoassay to Detect Serum Antibodies against the Hepatitis E Virus in Pigs, Using Plant-Derived ORF2 Recombinant Protein

Vaccines ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 991
Author(s):  
Katerina Takova ◽  
Tsvetoslav Koynarski ◽  
George Minkov ◽  
Valentina Toneva ◽  
Eugenia Mardanova ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Capsid Protein ◽  
Hepatitis E Virus ◽  
Hepatitis E ◽  
Blocking Agent ◽  
Oral Route ◽  
Youden Index ◽  
Common Source ◽  
Kappa Index ◽  
Pig Serum

Hepatitis E is an emerging global disease, mainly transmitted via the fecal–oral route in developing countries, and in a zoonotic manner in the developed world. Pigs and wild boar constitute the primary Hepatitis E virus (HEV) zoonotic reservoir. Consumption of undercooked animal meat or direct contact with infected animals is the most common source of HEV infection in European countries. The purpose of this study is to develop an enzyme immunoassay (EIA) for the detection of anti-hepatitis E virus IgG in pig serum, using plant-produced recombinant HEV-3 ORF2 as an antigenic coating protein, and also to evaluate the sensitivity and specificity of this assay. A recombinant HEV-3 ORF2 110-610_6his capsid protein, transiently expressed by pEff vector in Nicotiana benthamiana plants was used to develop an in-house HEV EIA. The plant-derived HEV-3 ORF2 110-610_6his protein proved to be antigenically similar to the HEV ORF2 capsid protein and it can self-assemble into heterogeneous particulate structures. The optimal conditions for the in-house EIA (iEIA) were determined as follows: HEV-3 ORF2 110-610_6his antigen concentration (4 µg/mL), serum dilution (1:50), 3% BSA as a blocking agent, and secondary antibody dilution (1:20 000). The iEIA developed for this study showed a sensitivity of 97.1% (95% Cl: 89.9–99.65) and a specificity of 98.6% (95% Cl: 92.5–99.96) with a Youden index of 0.9571. A comparison between our iEIA and a commercial assay (PrioCHECK™ Porcine HEV Ab ELISA Kit, ThermoFisher Scientific, MA, USA) showed 97.8% agreement with a kappa index of 0.9399. The plant-based HEV-3 ORF2 iEIA assay was able to detect anti-HEV IgG in pig serum with a very good agreement compared to the commercially available kit.

scholarly journals Hepatitis E Virus Immunopathogenesis

Pathogens ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1180
Author(s):  
Kush Kumar Yadav ◽  
Scott P. Kenney
Keyword(s):  
Hepatitis E Virus ◽  
Organ Transplant ◽  
Hepatitis E ◽  
Oral Route ◽  
Solid Organ ◽  
Immunocompromised Patients ◽  
In Vivo Models ◽  
Transplant Patients

Hepatitis E virus is an important emerging pathogen producing a lethal impact on the pregnant population and immunocompromised patients. Starting in 1983, it has been described as the cause for acute hepatitis transmitted via the fecal–oral route. However, zoonotic and blood transfusion transmission of HEV have been reported in the past few decades, leading to the detailed research of HEV pathogenesis. The reason behind HEV being highly virulent to the pregnant population particularly during the third trimester, leading to maternal and fetal death, remains unknown. Various host factors (immunological, nutritional, hormonal) and viral factors have been studied to define the key determinants assisting HEV to be virulent in pregnant and immunocompromised patients. Similarly, chronic hepatitis is seen particularly in solid organ transplant patients, resulting in fatal conditions. This review describes recent advances in the immunopathophysiology of HEV infections in general, pregnant, and immunocompromised populations, and further elucidates the in vitro and in vivo models utilized to understand HEV pathogenesis.

Determination of the Thermal Inactivation Kinetics of Listeria monocytogenes, Salmonella enterica, and Escherichia coli O157:H7 and non-O157 in Buffer and a Spinach Homogenate

2015 ◽  
Vol 78 (8) ◽  
pp. 1467-1471 ◽  
Author(s):  
EMEFA ANGELICA MONU ◽  
MALCOND VALLADARES ◽  
DORIS H. D'SOUZA ◽  
P. MICHAEL DAVIDSON
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Salmonella Enterica ◽  
Thermal Inactivation ◽  
Inactivation Kinetics ◽  
Mild Heat ◽  
Log Reduction ◽  
D Values ◽  
Heat Processes ◽  
Kinetics Of

Produce has been associated with a rising number of foodborne illness outbreaks. While much produce is consumed raw, some is treated with mild heat, such as blanching or cooking. The objectives of this research were to compare the thermal inactivation kinetics of Listeria monocytogenes, Salmonella enterica, Shiga toxin–producing Escherichia coli (STEC) O157:H7, and non-O157 STEC in phosphate-buffered saline (PBS; pH 7.2) and a spinach homogenate and to provide an estimate of the safety of mild heat processes for spinach. Five individual strains of S. enterica, L. monocytogenes, STEC O157:H7, and non-O157 STEC were tested in PBS in 2-ml glass vials, and cocktails of the organisms were tested in blended spinach in vacuum-sealed bags. For Listeria and Salmonella at 56 to 60°C, D-values in PBS ranged from 4.42 ± 0.94 to 0.35 ± 0.03 min and 2.11 ± 0.14 to 0.16 ± 0.03 min, respectively. D-values at 54 to 58°C were 5.18 ± 0.21 to 0.53 ± 0.04 min for STEC O157:H7 and 5.01 ± 0.60 to 0.60 ± 0.13 min for non-O157 STEC. In spinach at 56 to 60°C, Listeria D-values were 11.77 ± 2.18 to 1.22 ± 0.12 min and Salmonella D-values were 3.51 ± 0.06 to 0.47 ± 0.06 min. D-values for STEC O157:H7 and non-O157 STEC were 7.21 ± 0.17 to 1.07 ± 0.11 min and 5.57 ± 0.38 to 0.99 ± 0.07 min, respectively, at 56 to 60°C. In spinach, z-values were 4.07 ± 0.16, 4.59 ± 0.26, 4.80 ± 0.92, and 5.22 ± 0.20°C for Listeria, Salmonella, STEC O157:H7, and non-O157 STEC, respectively. Results indicated that a mild thermal treatment of blended spinach at 70°C for less than 1 min would result in a 6-log reduction of all pathogens tested. These findings may assist the food industry in the design of suitable mild thermal processes to ensure food safety.

Water-Borne Hepatitis E Virus Epidemic in Islamabad, Pakistan: A Common Source Outbreak Traced to the Malfunction of a Modern Water Treatment Plant

1997 ◽  
Vol 57 (2) ◽  
pp. 151-157 ◽  
Author(s):  
Mohammad Abdur Rab ◽  
Mohamud Khalif Bile ◽  
Hamayun Asghar ◽  
Mohammad Ilyas Burney ◽  
Zumra Sami ◽  
...  
Keyword(s):  
Water Treatment ◽  
Hepatitis E Virus ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Hepatitis E ◽  
Common Source ◽  
Water Borne

Serological and Molecular Investigation of Swine Hepatitis E Virus in Pigs Raised in Southern Italy

2015 ◽  
Vol 78 (11) ◽  
pp. 2099-2102 ◽  
Author(s):  
NICOLA COSTANZO ◽  
ELEONORA SARNO ◽  
VINCENZO PERETTI ◽  
LUCIA CIAMBRONE ◽  
FRANCESCO CASALINUOVO ◽  
...  
Keyword(s):  
Hepatitis E Virus ◽  
Southern Italy ◽  
Age Groups ◽  
Hepatitis E ◽  
Developed Countries ◽  
Oral Route ◽  
Enzyme Linked Immunosorbent Assay ◽  
Viral Genomes ◽  
Reverse Transcription Pcr ◽  
Significant Difference

Hepatitis E virus (HEV) infection is a common acute hepatitis transmitted by the fecal-oral route. In developed countries, the virus has a zoonotic potential, and domestic pigs and wild boars are considered main reservoirs. To assess the prevalence of HEV-positive animals in the Calabria region (southern Italy) on a serological and molecular level, a total of 216 autochthonous healthy pigs (Apulo-Calabrese breed) were sampled. Both sera and feces were collected. Pigs were grouped based on age: 117 pigs <6 months and 99 pigs >6 months. By using a commercial enzyme-linked immunosorbent assay system, a total of 173 (80%) of the 216 pigs tested seropositive. In all sampled farms (n = 8), pigs with antibodies (immunoglobulin G) against HEV were detected at a level higher than 60%, with a significant difference among age groups (P < 0.0001). Moreover, 16 fattening pigs were found to be nested reverse transcription PCR positive and thus to shed viral genomes in their feces. These positive findings resulted in a prevalence of 48.4% on the farm level (16 of 35 pigs) and an overall prevalence of 7.4% at the animal level (16 of 216 pigs). Based on the present study, HEV seems to circulate among the autochthonous domestic pig population of southern Italy with a low sharing rate. Further studies exploring the origin of infection are needed to minimize the risk of human exposure and to reduce consequences for public health.

scholarly journals Evaluation of High-Pressure Processing in Inactivation of the Hepatitis E Virus

2019 ◽  
Author(s):  
Neda Nasheri ◽  
Tanushka Doctor ◽  
Angela Chen ◽  
Jennifer Harlow ◽  
Alexander Gill
Keyword(s):  
High Pressure ◽  
Hepatitis E Virus ◽  
Foodborne Pathogen ◽  
Hepatitis E ◽  
Developed Countries ◽  
High Pressure Processing ◽  
Pathogen Inactivation ◽  
Genotype 3 ◽  
Similar Treatment ◽  
Log Reduction

Hepatitis E virus (HEV) causes acute hepatitis with approximately 20 million cases per year globally. While HEV is endemic in certain regions of Asia, Africa and South America, it is considered an emerging foodborne pathogen in developed countries. Based on genetic diversity, HEV is classified into different genotypes, with genotype 3 (HEV-3) being most prevalent in Europe and North America. The transmission of HEV-3 has been shown to be zoonotic and mainly associated with the consumption of raw or undercooked pork products. Herein, we investigated the efficacy of high-pressure processing (HPP) in the inactivation of HEV-3 using a cell culture system. HPP has been indicated as a promising nonthermal pathogen inactivation strategy for treatment of certain high-risk food commodities, without any noticeable changes in their nature. For this purpose, we treated HEV-3 in media as well as in artificially inoculated pork pâté, with different conditions of HPP: 400 MPa for 1 and 5 minutes, as well as 600 MPa for 1 and 5 minutes, at ambient temperature. In general, we observed approximately a 2-log reduction in HEV load by HPP treatments in media; however, similar treatment in the pork pâté resulted in a much lower reduction in viral load. Therefore, the efficacy of HPP treatment in the inactivation of HEV-3 is matrix-dependent.

scholarly journals Mechanism of Cross-Species Transmission, Adaptive Evolution and Pathogenesis of Hepatitis E Virus

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 909
Author(s):  
Putu Prathiwi Primadharsini ◽  
Shigeo Nagashima ◽  
Hiroaki Okamoto
Keyword(s):  
Adaptive Evolution ◽  
Hepatitis E Virus ◽  
Current Knowledge ◽  
Hepatitis E ◽  
Oral Route ◽  
Open Reading Frames ◽  
Industrialized Countries ◽  
Zoonotic Infection ◽  
Host Determinants ◽  
Viral Determinants

Hepatitis E virus (HEV) is the leading cause of acute hepatitis worldwide. While the transmission in developing countries is dominated by fecal-oral route via drinking contaminated water, the zoonotic transmission is the major route of HEV infection in industrialized countries. The discovery of new HEV strains in a growing number of animal species poses a risk to zoonotic infection. However, the exact mechanism and the determinant factors of zoonotic infection are not completely understood. This review will discuss the current knowledge on the mechanism of cross-species transmission of HEV infection, including viral determinants, such as the open reading frames (ORFs), codon usage and adaptive evolution, as well as host determinants, such as host cellular factors and the host immune status, which possibly play pivotal roles during this event. The pathogenesis of hepatitis E infection will be briefly discussed, including the special forms of this disease, including extrahepatic manifestations, chronic infection, and fulminant hepatitis in pregnant women.

scholarly journals Occurrence of water-borne enteric viruses in two settlements based in Eastern Chad: analysis of hepatitis E virus, hepatitis A virus and human adenovirus in water sources

2011 ◽  
Vol 9 (3) ◽  
pp. 515-524 ◽  
Author(s):  
Laura Guerrero-Latorre ◽  
Anna Carratala ◽  
Jesus Rodriguez-Manzano ◽  
Byron Calgua ◽  
Ayalkibet Hundesa ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Hepatitis E Virus ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Human Adenovirus ◽  
Hepatitis E ◽  
Water Sources ◽  
Human Adenoviruses ◽  
Water Borne

Hepatitis E virus (HEV) is a common cause of water-borne acute hepatitis in areas with poor sanitation. In 2004 an outbreak of HEV infection affected around 2,000 people in Eastern Chad (Dar Sila). This paper describes the decrease in the incidence of acute jaundice syndrome (AJS) from 2004 until 2009 when a mean incidence of 0.48 cases/1,000 people/year was recorded in the region. Outbreaks of AJS were identified in some of the camps in 2007 and 2008. Moreover, water samples from drinking water sources were screened for human adenoviruses considered as viral indicators and for hepatitis A virus and HEV. Screening of faecal samples from donkeys for HEV gave negative results. Some of the samples were also analysed for faecal coliforms showing values before disinfection treatment between 3 and >50 colony forming units per 100 mL. All water samples tested were negative for HEV and HAV; however, the presence of low levels of human adenoviruses in 4 out of 16 samples analysed indicates possible human faecal contamination of groundwater. Consequently, breakdowns in the treatment of drinking water and/or increased excretion of hepatitis viruses, which could be related to the arrival of a new population, could spread future outbreaks through drinking water.

Thermal Inactivation Kinetics of Salmonella spp. within Intact Eggs Heated Using Humidity-Controlled Air

2001 ◽  
Vol 64 (7) ◽  
pp. 934-938 ◽  
Author(s):  
R. E. BRACKETT ◽  
J. D. SCHUMAN ◽  
H. R. BALL ◽  
A. J. SCOUTEN
Keyword(s):  
Thermal Inactivation ◽  
Inactivation Kinetics ◽  
Glass Capillary ◽  
Salmonella Spp ◽  
Shell Eggs ◽  
Log Reduction ◽  
Liquid Whole Egg ◽  
D Values ◽  
Kinetics Of ◽  
Whole Egg

The heat resistance of six strains of Salmonella (including Enteritidis, Heidelberg, and Typhimurium) in liquid whole egg and shell eggs was determined. Decimal reduction times (D-values) of each of the six strains were determined in liquid whole egg heated at 56.7°C within glass capillary tubes immersed in a water bath. D-values ranged from 3.05 to 4.09 min, and significant differences were observed between the strains tested (α = 0.05). In addition, approximately 7 log10 CFU/g of a six-strain cocktail was inoculated into the geometric center of raw shell eggs and the eggs heated at 57.2°C using convection currents of humidity-controlled air. D-values of the pooled salmonellae ranged from 5.49 to 6.12 min within the center of intact shell eggs. A heating period of 70 min or more resulted in no surviving salmonellae being detected (i.e., an 8.7-log reduction per egg).

Ultraviolet inactivation of bacteria and model viruses in coconut water using a collimated beam system

2019 ◽  
Vol 25 (7) ◽  
pp. 562-572 ◽  
Author(s):  
Manreet S Bhullar ◽  
Ankit Patras ◽  
Agnes Kilonzo-Nthenge ◽  
Bharat Pokharel ◽  
Michael Sasges
Keyword(s):  
Pathogenic Bacteria ◽  
Microbial Inactivation ◽  
Coconut Water ◽  
Inactivation Kinetics ◽  
E Coli ◽  
Log Reduction ◽  
Ultraviolet C ◽  
Log Linear ◽  
Kinetics Of ◽  
Collimated Beam

This study investigated the effect of ultraviolet-C irradiation on the inactivation of microorganisms in coconut water, a highly opaque liquid food (1.01 ± 0.018 absorption coefficient). Ultraviolet-C inactivation kinetics of two bacteriophages (MS2, T1UV) and three surrogate bacteria ( Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes) in 0.1% (w/v) peptone and coconut water were investigated. Ultraviolet-C irradiation at 254 nm was applied to stirred samples, using a collimated beam device. A series of known ultraviolet-C doses (0–40 mJ cm−2) were applied for ultraviolet-C treatment except for MS2 where higher doses were delivered (100 mJ cm−2). Inactivation levels of all organisms were proportional to ultraviolet-C dose. At the highest dose of 40 mJ cm−2, three surrogates of pathogenic bacteria were inactivated by more than 5-log10 (p < 0.05) in 0.1% (w/v) peptone and coconut water. Results showed that ultraviolet-C irradiation effectively inactivated bacteriophage and surrogate bacteria in highly opaque coconut water. The log reduction kinetics of microorganisms followed log-linear and exponential models with higher R2 (>0.95) and low root mean square error values. The D10 values of 3, 5.48, and 4.58 mJ cm−2 were obtained from the inactivation of E. coli, S. Typhimurium, and L. monocytogenes, respectively. Models for predicting log reduction as a function of ultraviolet-C irradiation dose were found to be significant (p < 0.05). Fluid optics were the key controlling parameters for efficient microbial inactivation. Therefore, the ultraviolet-C dose must be calculated not only from the incident ultraviolet-C intensity but must also consider the attenuation in the samples. The results from this study imply that adequate log reduction of vegetative cells and model viruses is achievable in coconut water and suggested significant potential for ultraviolet-C treatment of other liquid foods.

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