Presence Of Hepatitis E Virus Research Articles

Hepatitis E virus in sheep in Italy.

Hepatitis E virus (HEV) is the leading cause of human enterically transmitted viral hepatitis occurring around the world both as outbreaks and as sporadic cases. The accumulating literature indicates that domestic pigs and wild boars are the main reservoirs of genotype 3 and genotype 4 for human infections in industrialized countries. However, the recent identification of HEV from various animal species poses additional potential concerns for HEV zoonotic infection. In this study, the role of sheep as potential host of hepatitis E virus (HEV) was investigated. By screening 192 sheep from seven farms located in Abruzzo Region (Southern Italy), HEV-specific antibodies were detected in the sera of 41 animals (21.3%) whilst the RNA of HEV, genotype 3, was detected in 20 faecal (10.4%) and three serum samples (1.6%). Upon sequence analyses of a partial ORF2 gene region of eight HEV positive samples, the sheep sequences all grouped together within HEV genotype 3 subtype c, being most closely related to HEV strains identified in goat and wild boar from Abruzzo. This is the first study that demonstrates, serologically and molecularly, the presence of HEV in sheep population in a European country.

Detection of Hepatitis E Virus in Raw Pork and Pig Viscera As Food in Hebei Province of China.

Hepatitis E virus (HEV) is an important human pathogen with pigs serving as the main natural animal reservoir. In China, pork is the most popular meat, while pig viscera are also widely consumed. The aim of this study was to evaluate the prevalence of HEV among pigs at slaughter, and assess the presence of HEV in raw pork and pig viscera as food. Samples of pig blood, raw pork, liver, kidney, and blood curd were collected from slaughterhouse or (and) retail market. Anti-HEV antibody in serum samples was detected using enzyme-linked immunosorbent assay based on an ORF2 antigen sandwich kit. HEV RNA was tested by reverse transcription nested polymerase chain reaction (RT-nested PCR) and the viral load was further assessed using quantitative real-time PCR. The final amplicons of RT-nested PCR were sequenced and undergone phylogenetic analysis. Prevalence of antibodies to HEV was 90.4% (104/115) in pigs at slaughtered level, and one serum sample was HEV RNA positive (0.9%, 1/115). HEV RNA was detected in liver, kidney, and blood samples with positivity of 6.1% (7/114), 3.1% (4/129), and 1.2% (2/170) respectively with viral loads ranged 102.4-104.4 (2.4Log-4.4Log) genome equivalents per gram, but not in pork. The HEV RNA prevalence in both liver and kidney were statistically higher than in pork. Phylogenetic analysis showed that all obtained sequences belonged to HEV genotype 4, which were divided into subtypes 4a, 4b, 4d, and 4i, highly identical to the known human and swine HEV sequences in China. The results indicate that raw pig viscera are more likely to harbor HEV than pork, suggesting a higher transmission risk related to consuming pig organs.

Detection of HEV RNA amounts and genotypes in raw milks obtained from different animals

Hepatitis E virus (HEV) is one of the major foodborne viral pathogens transmitted through the fecal-oral route. Four genotypes of HEV are known to infect humans and it is reported that different types of HEV are active in zoonotic transitions. It is known that the HEV genotype 1 and HEV genotype 2 infections are generally acute and the HEV genotype 3 infections are chronic. Therefore, in the studies related to HEV infections, it is important to determine the genotypes to monitortreatment regimens. Although raw milk is often used in communities due to its low cost, there are limited data on the rates and the genotypes of HEV in our country and in the world. In light of this information, we aimed to investigate epidemiologically the quantity and genotypes of HEV RNA in 231 raw milk (48 cow milk, 65 goat milk, 65 sheep milk, and 53 donkey milk) samples. Viral RNAs were isolated from raw milk samples and the ORF2 region of HEV was investigated by the qRt-PCR method to determine quantitatively the presence of HEV RNA. In addition, among HEV RNA positive samples, the ORF2 region of HEV was amplified by nested PCR and the amplicons were sequenced. HEV RNA was detected in 47 (20.34%) raw milk samples, Positivity was detected in 14 (29.16%) of cow milk, 12 (18.46%) of goat milk, 8 of sheep milk (12.3) and 13 of donkey milk (24.5%). The amount of HEV RNA in cow milk found as the highest in both proportion and quantity. When the distribution of the HEV genotypes in the 47 positive samples was examined, 27 (57.44%) HEV genotype 1a, 10 (21.27%) HEV genotype 1b, 4 (8.5%) HEV genotype 4c, 2 (4.2%) HEV genotype 3a, (2.13) HEV genotype 1c, 1 (2.13%) HEV genotype 3e, 1 (2.13%) HEV genotype 3f and 1 (2.13%) HEV genotype 3g were determined. Although genotype 1a is more frequent, it has been revealed that different genotypes encountered in our country. In conclusion, it has been determined that HEV, one of the major foodborne viral agents, may be encountered in raw milk, and the genotypes that can cause infections in human are found especially in raw milk from animal sources. For the prevention of foodborne outbreaks, the presence of HEV in raw milk should not be ignored.

Evolutionary study of potentially zoonotic hepatitis E virus genotype 3 from swine in Northeast Brazil

Hepatitis E virus (HEV), an emerging virus associated with acute hepatic disease, leads to thousands of deaths worldwide. HEV has already been reported in Brazil; however, there is a lack of epidemiological and molecular information on the genetic variability, taxonomy, and evolution of HEV. It is thus unclear whether hepatitis E is a neglected disease in Brazil or it has low relevance for public health in this country. Here, for the first time, we report the presence of HEV in Northeast Brazil. A total of 119 swine faecal samples were screened for the presence of HEV RNA using real-time polymerase chain reaction (RT-PCR) and further confirmed by conventional RT-PCR; among these, two samples were identified as positive. Molecular evolution analyses based on capsid sequences revealed that the samples had close proximities to HEV sequences belonging to genotype 3 and were genetically related to subtype 3f isolated in humans. Parsimony ancestral states analysis indicated gene flow events from HEV cross-species infection, suggesting an important role of pig hosts in viral spillover. HEV’s ability for zoonotic transmission by inter-species host switching as well as its possible adaptation to new animal species remain important issues for human health.

Persistent viremia and presence of hepatitis E virus RNA in pig muscle meat after experimental co-infection with porcine reproductive and respiratory syndrome virus

Although hepatitis E virus (HEV) transmission has been demonstrated after consumption of products containing infected pig liver, human cases can be also associated with other pig meat products, such as sausages. Data on HEV viremia and dissemination in muscle meat of infected animals are still sparse, especially during long-term infection. Previously, we have shown that experimental co-infection of pigs with HEV and porcine reproductive and respiratory syndrome virus (PRRSV) lengthens HEV infection up to 49 days and increases the likelihood of the presence of HEV RNA in the liver of the pig at a later stage of infection. In the present study, we show that during experimental HEV-PRRSV co-infection, prolonged HEV viremia, up to 49 days post-inoculation (dpi), is detected. The long-term viremia observed was statistically associated with the absence of HEV seroconversion. HEV RNA was also frequently detected, at a late stage of infection (49 dpi), in the three different types of muscle tested: femoral biceps, psoas major or diaphragm pillar. The HEV RNA load could reach up to 1 · 106 genome copies per gram of muscle. Detection of HEV in muscle meat was statistically associated with high HEV loads in corresponding liver and fecal samples. The presence of HEV in pig blood, femoral biceps and major psoas, corresponding to ham and tenderloin muscles respectively, is of concern for the food industry. Hence, these results indicate new potential risks for consumers and public health regarding pork products.

Risk analysis and seroprevalence of HEV in people living with HIV/AIDS in Brazil

Acute Hepatitis E virus (HEV) infection in people living with HIV/AIDS (PLHA) can lead to fulminant hepatic failure, cirrhosis and death. The prevalence of anti-HEV antibodies within this group varies according to the geographical area. However, in South America, studies concerning the detection of HEV in PLHA are rare. Here, we investigated the presence of HEV by serological and molecular detection and evaluated the risk factors associated with infection in PLHA in Pernambuco state, Brazilian Northeast. Serological and molecular detection of HEV was performed in 366 samples of PLHA by ELISA for anti-HEV IgG and RT-PCR, respectively. Anti-HEV IgG prevalence was 4.1% (15/366) and no HEV RNA was detected. Concerning the risk factors, we evaluated, in multivariable analysis, age, years of school, sexual orientation, oral-anal sex, use of injectable drugs and piped water. Among them, only piped water availability could be associated with the HEV infection in PLHA (OR: 0.08; CI 95%: 0.01–0.66; p = 0.0182). This study showed for the first time the association of piped water as protection factor for HEV infection in PLHA. Finally, this is also the first report of HEV seroprevalence in PLHA in the Northeast Brazil.

Short communication: detection and molecular characterization of hepatitis E virus in domestic animals of São Tomé and Príncipe.

As in most of the African continent, the status of hepatitis E virus (HEV) infection in domestic animals in São Tomé and Príncipe, an archipelago off the western equatorial coast of Central Africa, is also completely unknown. In the present study, we investigated the presence of HEV among domestic animals in São Tomé and Príncipe. A total of 93 stool samples from different animal species (goat, cow, pig, chicken, duck, and monkey) were tested for HEV RNA using two real-time RT-PCR assays, followed by a nested RT-PCR assay for sequencing and phylogenetic analysis. A total of six samples (1 cow stool and 5 pig stools) were found to be positive for HEV RNA of which one pig stool was positive by broad spectrum nested RT-PCR. Phylogenetic analysis showed that the retrieved sequence clustered within HEV subgenotype 3f, similar to zoonotic strains of European countries and posing interesting questions on past introduction of European HEV into São Tomé and Príncipe archipelago. This is the first report describing the presence and molecular characterization of HEV in São Tomé and Príncipe.

Hepatitis E Virus: Zoonotic and Foodborne Transmission in Developed Countries

Hepatitis E virus (HEV), together with hepatitis A virus, transmits via the fecal–oral route. The number of domestic hepatitis E cases among Europeans has grown alarmingly during the past 5 years. Surveillance studies suggest that the number of foodborne HEV infections is increasing most rapidly. Zoonotic HEV genotype HEV-3 is prevalent among pigs and wild boars in Europe and many developed countries, whereas zoonotic genotype HEV-4 is more common in pigs in some Asian countries. This review presents the most recent data about possible foodborne transmission of HEV via pigs and other production animals and about the presence of HEV in high-risk foods, such as ready-to-eat meat products. Possible solutions about how to tackle this problem are discussed here.

Serological and molecular investigation for hepatitis E virus (HEV) in captive non-human primates, Italy

Hepatitis E virus (HEV) is the leading cause of human enterically-transmitted viral hepatitis occurring around the world both as outbreaks and as sporadic cases. Non-human primates (NHPs) have been experimentally infected with HEV, but few studies have been reported about natural infection in wild-living and zoo monkeys. In order to provide a more complete picture on the epidemiology of HEV in NHPs living in controlled environment, we investigated the presence of HEV by screening serologically and molecularly a historical collection of 86 sera from seven different species of primates housed at the Zoological Garden (Bioparco) of Rome, Italy. By using an enzyme-linked immunosorbent assay based on the recombinant capsid protein of a Gt3 HEV strain, IgG antibodies were detected in three macaques (4.8%; 3/62) and in a white-crowned mangabey (16.6%; 1/6), with an overall prevalence of 4.6% (4/86). This positivity was confirmed when assessed the sera by western blotting. Rescreening the sera for IgM and viral RNA, all the samples resulted negative. Also, HEV RNA was not found when 17 stool samples were analyzed by RT-PCR. Although these results suggest that none of the monkeys housed at the Bioparco of Rome in the 17-year time frame spanning 2001 to 2017 developed acute or at least sub-acute HEV disease, the detection of IgG antibodies demonstrated that animals living in this setting were exposed to HEV or to antigenically related viruses.

Hepatitis E virus in lettuce and water samples: A method-comparison study

The hepatitis E virus (HEV), which is an increasing cause of acute viral hepatitis in Europe, is a zoonotic virus that is mainly transmitted through contaminated water, consumption of raw or undercooked meat from pigs or wild boar, blood transfusion, and organ transplantation. Although the role of HEV transmission through contaminated produce has not been confirmed, the presence of HEV has been reported in irrigation waters and in vegetables. The present study used a World Health Organization (WHO) international standard and clinical samples to evaluate the performance characteristics of three RT-qPCR assays for detection and quantification of HEV. Two of the evaluated assays provided good analytical sensitivity, as 250 international units (IU) per ml could be detected. Then, experiments focused on evaluating the elution conditions suitable for HEV release from vegetables, with the method proposed by the ISO 15216:2017 selected for evaluation in three types of fresh vegetables. The concentration method proposed by the ISO 15216:2017 combined with the RT-qPCR described by Schlosser et al. (2014) resulted in average HEV recoveries of 1.29%, 0.46%, and 3.95% in lettuce, spinach, and pepper, respectively, with an average detection limit of 1.47 × 105 IU/25 g. In naturally contaminated samples, HEV was detected in sewage only (10/14), while no detection was reported in lettuce (0/36) or in irrigation water samples (0/24).

Screening of Ready-to-Eat Meat Products for Hepatitis E Virus in Switzerland

Seroprevalence data for pig herds suggested that there must be a relevant reservoir for hepatitis E virus (HEV) in Switzerland. To know more about the viral presence in ready-to-eat meat products, we screened pork liver sausages and raw meat sausages from the Swiss retail market for the presence of HEV. Testing was performed with a detection method where the virus extraction step was optimized. As for the performance of the improved method, the mean recovery rate for the mengovirus process control was 24.4%, whereas for HEV-inoculated sample matrices between 10.4 and 100% were achieved. The limit of detection was about 1.56 × 103 and 1.56 × 102 genome copies per gram for liver sausages and raw meat sausages, respectively. In the screening programme, HEV-RNA was detected in 10 of total 90 (11.1%) meat products, 7 of 37 (18.9%) liver sausages, and 3 of 53 (5.7%) raw meat sausages. Virus loads of up to 5.54 log10 HEV genome copies per gram were measured. All sequences retrieved from positive samples belonged to HEV genotype 3. The significance of the presented work was a current overview of the HEV prevalence in ready-to-eat meat products on the Swiss retail marked and an improvement of the extraction efficiency of the HEV detection method.

Quantitative risk assessment of hepatitis E virus: Modelling the occurrence of viraemic pigs and the presence of the virus in organs of food safety interest

Hepatitis E virus (HEV) is a zoonotic pathogen with consumption of pork and derived products identified in different countries as a risk factor for human exposure to HEV. Great efforts have been made to understand the dynamics of virus transmission within domestic swine populations through modelling. However, from a food safety prospective, it is critical to integrate the parameters involved in the transmission dynamics with those governing the actual presence of HEV in the bloodstream, the liver, gallbladder or faeces. To date, several aspects related to the pathogenesis of the disease are still unknown or characterized by significant levels of uncertainty, making this conjunction challenging. We used published serological data obtained from pigs in a farrow-to-finish farm to implement an Immune-Susceptible-Infected-Recovered (MSIR) model reproducing the on-farm dynamics that lead to the occurrence of viraemic pigs at slaughter. Expert opinion on the length of time infectious HEV can be detected in liver, gallbladder/bile and faeces after recovery from viraemic status were used to inform a stochastic model aimed at estimating the expected proportion of viraemic pigs, pigs with infectious HEV in liver, gallbladder/bile and faeces entering the slaughterhouse. To simulate the potential effect of on-farm mitigation strategies, we estimated the changes in outcomes of interest as a function of variations in the baseline transmission parameters. The model predicted a proportion of viraemic pigs entering the slaughterhouse of 13.8% while the proportions of, and ranged from 13.8% to 94.4%, 13.8% to 94.7% and from 25.3% to 30.8% respectively, due to the uncertainty surrounding the experts’ opinions. Variations in MSIR model’s parameters alert of the need to carefully consider the application of mitigation strategies aimed at delaying the decay of maternal immunity or the peak of the within herd transmission. When the rate of decay of maternal immunity and the transmission rate were decreased between 80% and 5% and 40% and 5% from the baseline values respectively, adverse effects on were observed. The model highlights the relevance of specific aspects in the pathogenesis of the disease from a food safety prospective and it was developed to be easily reproducible and updatable as soon as accurate data becomes available. As presented, the model can be directly connected to existing or future pig-related models to estimate the significance of the identified parameters on the risk of human exposure to HEV through consumption of pork products.

Detection of Hepatitis E Virus RNA in Raw Cured Sausages and Raw Cured Sausages Containing Pig Liver at Retail Stores in Switzerland

Hepatitis E virus (HEV) is the causative agent of an acute and self-limiting hepatitis and is increasingly detected in food products containing pork. In this study, 102 raw sausages containing pig liver (mortadella di fegato) and 18 raw pork sausages (salami type sausage) collected at retail level in a region of southern Switzerland were screened for the presence of HEV by quantitative real-time reverse transcription PCR. HEV was detected in 12 (11.8%) of 102 mortadella di fegato products but not in any of the salami sausages. Viral loads in the mortadella di fegato sausages ranged from log HEV 2.3 to 5.7 genome copies per gram of food product. This study identifies mortadella di fegato type sausages made with raw pig liver as a potential source of HEV infection in humans.

Hepatitis E virus and related viruses in wild, domestic and zoo animals: A review.

Hepatitis E is a human disease mainly characterized by acute liver illness, which is caused by infection with the hepatitis E virus (HEV). Large hepatitis E outbreaks have been described in developing countries; however, the disease is also increasingly recognized in industrialized countries. Mortality rates up to 25% have been described for pregnant women during outbreaks in developing countries. In addition, chronic disease courses could be observed in immunocompromised transplant patients. Whereas the HEV genotypes 1 and 2 are mainly confined to humans, genotypes 3 and 4 are also found in animals and can be zoonotically transmitted to humans. Domestic pig and wild boar represent the most important reservoirs for these genotypes. A distinct subtype of genotype 3 has been repeatedly detected in rabbits and a few human patients. Recently, HEV genotype 7 has been identified in dromedary camels and in an immunocompromised transplant patient. The reservoir animals get infected with HEV without showing any clinical symptoms. Besides these well-known animal reservoirs, HEV-specific antibodies and/or the genome of HEV or HEV-related viruses have also been detected in many other animal species, including primates, other mammals and birds. In particular, genotypes 3 and 4 infections are documented in many domestic, wildlife and zoo animal species. In most cases, the presence of HEV in these animals can be explained by spillover infections, but a risk of virus transmission through contact with humans cannot be excluded. This review gives a general overview on the transmission pathways of HEV to humans. It particularly focuses on reported serological and molecular evidence of infections in wild, domestic and zoo animals with HEV or HEV-related viruses. The role of these animals for transmission of HEV to humans and other animals is discussed.

First evidence of the Hepatitis E virus in environmental waters in Colombia.

Hepatitis E virus (HEV) is one of the main causes of acute viral hepatitis of enteric transmission. HEV has been detected in environmental samples in several countries from Europe and Asia, constituting a risk factor for waterborne infection. In Colombia, HEV has been identified in samples obtained from patients as well as from swine, but no environmental studies have been carried out. To determine if HEV is present in environmental waters, samples from the main source of drinking water plant and of wastewater system of eight municipalities and two villages of Antioquia state (North West Colombia), were collected between December 2012 and April 2014. The HEV genome was detected by RT-PCR in 23.3% (7/30) of the samples from the main source of drinking water plants and in 16.7% (5/30) from sewage. Viral concentrates obtained from three positive sewage samples were used to inoculate HepG2 cell cultures that were followed for one month; however, the viral genome was not detected in any cell culture. This study demonstrates the circulation of HEV in both source of drinking water plants and wastewater in Antioquia state, Colombia. The presence of HEV in environmental waters could be a risk for waterborne transmission in this population. The findings of the present study, together with the evidence of HEV circulation in human and swine in Colombia, should be consider by public health authorities for the development of surveillance programs and the inclusion of HEV infection diagnosis in the guidelines of viral hepatitis in the country. This is the first report of HEV in environmental samples in Colombia and the second one in Latin America.

Seroprevalence of hev antibodies in a sample of pregnant women in the city of Messina.

Hepatitis E virus (HEV) is widespread in developing countries and the disease is also increasing in the developed ones. This infection in pregnancy can cause spontaneous abortion and neonatal death in 56% of newborns. The study was conducted on a sample of 352 pregnant women, 326 Italian and 26 foreign, in order to confirm the presence of HEV in our territory, to analyze wrong habits of the population and to suggest preventive actions against the risk to contract the infection during pregnancy. We asked all women under study to fill an anonymous questionnaire immediately before taking a venous blood samples to determine the presence of anti-HEV antibodies. The questionnaire contained a set of questions to gain information about lifestyles and risk factors to contract HEV. The questionnaire revealed that a portion of the tested women have risk behaviours, as consumption of raw or undercooked food, eating unwashed food and traveling to endemic areas. The percentage of women positive for HEV antibodies was 3.4%, in agreement with national data; all the women were Italian. This study confirms the circulation of HEV in the city of Messina. For this reason, it is highly recommended to disseminate hygienic and appropriate behaviours and feeding habits in order to prevent the risk to contract the infection.

Serological evidence of hepatitis e virus activity among slaughtered pigs and in selected pig farms in Ibadan, Nigeria: Implications for zoonotic transmission ?

Hepatitis E (HE) is endemic and of public health importance in many developing countries where poor sanitation condition has been identified as its major predisposing factor. In Europe and America, direct contact with pigs is linked with the presence of HE virus (HEV) in humans. However, despite poor sanitary conditions in many Nigerian communities, and established contacts between occupationally exposed individuals and pigs, limited studies have been conducted on HEV in pigs in Nigeria with unknown associated public health impact. Thus, this preliminary study was designed to investigate serologic evidence of HEV activity in pigs slaughtered at Bodija municipal abattoir and those reared on six swine farms in Ibadan, southwest Nigeria. The sera were screened for anti-HEV antibodies using a commercial ELISA kit that was developed based on a capsidderived recombinant antigen of genotype 3 HEV. Overall, 57.4% (101/176) of the sera reacted against genotype 3 HEV with 31.3% (55/176) and 26.1% (46/176) of abattoir and farm pigs, respectively being seropositive. No significant differences in HEV seropositivity were observed between sexes and breeds but a significantly higher seroprevalence was obtained for farm pigs compared to abattoir pigs in the 7-12 months age group. Women and young girls were observed to be majorly involved in pig slaughtering at the abattoir, thus constituting an occupationally exposed population that could be potentially infected and transmit the disease. These findings highlight the need for large-scale investigations of pigs and individuals that are occupationally at-risk individuals order to determine the actual burden of HEV infections in Nigeria.

Hepatitis E Virus in Pork and Variety Meats Sold in Fresh Markets.

Swine is an economically important livestock, yet pork consumption and close contact with pigs are associated with the risk of hepatitis E virus (HEV) infection. Limited data on the prevalence of HEV in Southeast Asia have mainly examined farm animals. To investigate the potential zoonotic transmission of HEV from dietary consumption of pork and variety meats (i.e., offal or organ meats), we obtained 1090 liver, 559 pork meat, and 556 intestine samples from fresh markets in the Bangkok metropolitan area between November 2014 and February 2015. The presence of HEV was assessed using reverse-transcription polymerase chain reaction. Concurrently, 720 bile and 553 fecal samples from a slaughterhouse were also examined. Overall, HEV RNA was found in 0.23% of the market samples and 3.93% of the slaughterhouse samples. Fecal and bile samples were more likely to test positive compared to liver, pork, and intestine samples (p<0.001). Phylogenetic analysis showed that all HEV sequences obtained in this study formed a cluster closely related to genotype 3f. Pork and variety meats derived from pigs are commonly sold in fresh markets throughout Southeast Asia. Here, a relatively low HEV prevalence from pork and variety meats sold in Bangkok was found. Additional studies will be required to further assess potential dietary transmission of HEV elsewhere in the region.

Hepatitis E viral loads in plasma pools for fractionation.

It is now recognized that blood donors may be silently infected with hepatitis E virus (HEV) and that plasma pools used in the manufacture of plasma-derived medicinal products may also contain detectable virus RNA. The occurrence of HEV-infected blood and plasma donors can vary considerably depending on local epidemiology. Manufacturing plasma pools from North America, Europe, the Middle East, and Asia were examined for the presence of HEV using transcription-mediated amplification of HEV RNA; confirmatory testing was performed using real-time reverse transcription polymerase chain reaction and sequencing. A total of 484 pools were tested. Asian pools were most frequently positive for HEV RNA and had higher viral loads, although none exceeding 300 IU/mL, and the sequenced strains (n = 5) clustered with Genotype 4, including one significantly divergent sequence. Only HEV Genotype 3 was identified in North American (n = 5) and European (n = 5) pools. There was no evidence of HEV in any pools tested from the Middle East. HEV was detected in manufacturing plasma pools from three different continents; viral loads were low-consistent with large pool sizes and moderate levels of HEV viremia at the individual donation level-but are nevertheless informative for risk assessment of plasma-derived medicinal products. Where sequencing was possible, analysis confirmed the presence of viruses consistent with locally circulating genotypes in the respective regions. The absence of HEV in Middle Eastern pools is consistent with the low prevalence of HEV in this region, likely due to low pork consumption.

Detection and Phylogenetic Analysis of the Hepatitis E Virus in a Canadian Swine Production Network.

Viral contamination along the production chain is a significant concern in both food safety and livestock health. Pigs have been reported to act as a reservoir for zoonotic viruses, sometimes emerging ones, and epidemiological studies have shown direct links between the consumption of uncooked pork offal and cases of hepatitis caused by the hepatitis E virus (HEV) genotype 3 in humans. The presence of HEV in swine herds has been reported, but its dissemination in pork production environments is still unknown. To investigate viral contamination sources in the swine industry, 452 environment and fecal samples, including samples from livestock transportation vehicles, were collected over a period of 11months from ten farms and one slaughterhouse that together represent a single production network. Hepatitis E virus RNA was detected by nested RT-PCR in 32 samples from both inside and outside farm buildings, on trucks, and, mostly, from fomites collected in the slaughterhouse yard, such as on a utility vehicle. Phylogenetic analysis showed a wide diversity of HEV genotype 3 strains, similar to human and swine strains previously found. According to the results of this study, the movements of trucks and utility vehicles might play an important role in HEV dissemination on a slaughterhouse site and throughout an entire network.