Risk Of Hepatitis E Virus Transmission Research Articles

Human-swine interface: is the hepatitis E virus a real risk for humans?

Abstract Background Hepatitis E virus (HEV) is the agent of hepatitis E, an emerging public-health infection with an increasing incidence in Europe. Due to the apparent lack of species barriers, HEV is considered a zoonotic agent, with swine as the main reservoir. This study investigated HEV prevalence in humans and domestic pigs in Northern Italy, a highly anthropic area with the highest pig farm density, to gain insights into the risk of HEV transmission from swine to humans. Methods A total of 508 blood samples were collected from blood donors (341 males and 167 females; from 18 to 66 years old) and from 1619 pigs in 40 different farms. Serological analyses were performed with ELISA to detect anti-HEV antibodies. In addition, 120 faecal pool samples collected from the pig farms with the highest seroprevalence and 69 salami produced in the same area were analysed to detect viral genome by Real-time PCR. Results In humans, HEV seroprevalence was 4.9% (CI95% 0.03-0.07); positive donors were mainly males, with seroprevalence increasing up to 12% (CI95% 0.09-0.15) in the 46-55 age group. Seroprevalence in swine was 53.00% (CI95% 0.50-0.55), with HEV detected in only 1% (CI95% 0.001-0.045) faeces. All food samples tested negative. Conclusions Even if the seroprevalence in pigs highlighted that HEV was actively circulating in the farms, the low seroprevalence in humans, the scarce HEV detection in swine faeces, and the absence in food products suggested that HEV transmission via faecal-oral or foodborne routes is unlikely, probably due to the implementation of severe biosecurity measures and high standards of hygiene in swine farms, and the continuous assessment of the critical points in the pig supply chain (from farm to fork). The serological surveillance of humans and the monitoring of farmed animals are needed to support the competent authorities in timely managing public health issues, improving human health and veterinary safety from a One Health perspective. Key messages • In the human-swine interface is important to monitor HEV presence. • The One Health approach is essential to control zoonotic diseases.

Lack of Evidence of Hepatitis E Virus Infections in a Cohort of Boars and Deer Species in a Game Reserve in Northern Germany

The risk of acquiring hepatitis E virus (HEV) infections by wild animals living in the European wild nature has previously been reported and high anti-HEV antibody detection rates were detected in several animal species. However, data on the HEV seroprevalence of wild boars and deer held in game reserves are rare. In the present study, we investigated anti-HEV seroprevalence and HEV RNA in 38 deer and 15 wild boars living in a game reserve in Northern Germany. Surprisingly, none of the animals tested positive for HEV RNA in blood, liver, or muscle (diaphragm), and all animals (n = 53, 100%) were anti-HEV negative. In conclusion, HEV infections in enclosed areas, such as game reserves, in Germany are rare, and the risk of HEV transmission through meat from these animals to humans seems to be low.

Nationwide survey of hepatitis E virus infection among wildlife in Japan

In Japan, hepatitis E virus (HEV) causes hepatitis in humans through the consumption of raw or undercooked meat, including game meat. In the present study, nationwide surveillance of HEV infection among a total of 5,557 wild animals, including 15 species, was conducted in Japan. The prevalence of anti-HEV antibodies in wild boar was 12.4%, with higher positive rates in big boars (over 50 kg, 18.4%) than in small individuals (less than 30 kg, 5.3%). Furthermore, HEV RNA was more frequently detected in piglets than in older boars. Interestingly, the detection of HEV among wildlife by ELISA and RT-PCR suggested that HEV infection in Sika deer was a very rare event, and that there was no HEV infection among wild animals except for wild boar, Sika deer and Japanese monkeys. In conclusion, wild boar, especially piglets, are at high risk of HEV infection, while other wild animals showed less risk or no risk of HEV transmission.

Detection of antibodies against hepatitis E virus in pet veterinarians and pet dogs in South Korea

Hepatitis E virus (HEV) is a zoonotic pathogen commonly considered an important foodborne virus. Pet dogs are important reservoirs of zoonotic agents. In the present study, the seroprevalence of HEV in pet dogs and pet veterinarians were found to be 28.2 and 5.0%, respectively. It remains unclear whether pet veterinarians are at higher risk of HEV transmission. However, pet animals and individuals who have contact with infected animals must be continually monitored for public health concerns.

High seroprevalence of hepatitis E among pigs suggests an animal reservoir in Cameroon.

Hepatitis E virus (HEV) is one of the most prevalent cause of acute hepatitis in humans worldwide. The risk of HEV transmission is not limited only to spread from human to human but the infection can also spread from animals to humans, especially from the domestic pigs. Despite mounting evidence regarding the zoonotic potential of porcine HEV infection, there are limited data on its prevalence in pigs in the sub-Sahara Africa region. Therefore, the present study aimed to determine the seroprevalence of HEV antibodies among pigs in two Cameroonian regions. A total of 162 sera were collected from slaughtered-age pigs from January to March 2012. To determine whether pigs might represent a HEV reservoir in the Northern and Western region in Cameroon, anti-HEV IgG and IgM were tested by ELISA using commercials available kits. Overall, 70 of the 162 samples (43.2%, 95% CI: 35.5% - 51.2%) were positive for at least one of the serological markers of HEV infection (IgM and / or IgG).We observed a significant seroprevalence of HEV antibodies between the northern and western regions (60% (42/70) and 40% (28/70), p = 0.01796) respectively. Overall, this study reports a high seroprevalence of Hepatitis E virus antibodies in slaughter pigs in Cameroon. Our findings suggest that pigs might be a cause of zoonotic HEV transmission in Cameroon. Therefore, further studies are warranted to establish the dynamics of zoonotic HEV and characterize the different genotypes circulating in humans and pigs.

Application of ELISA kit for the detection of hepatitis E virus antigen in plasma donations

Objective To analyze the practicability of using ELISA kit for the detection of hepatitis E virus antigen (HEV-Ag) in plasma donations and Biomex HEV seroconversion panels. Methods The HEV-Ag positive samples were screened out from 36 340 donated blood plasma samples. Real-time fluorescent PCR was performed for the detection of HEV RNA in HEV-Ag positive samples. The open reading frame 2 (ORF2) in HEV RNA was amplified by nested RT-PCR and the amplified products were confirmed by sequencing analysis. Phylogenetic tree was constructed for HEV genotyping. Five Biomex HEV seroconversion panels were used in this study for the detection of HEV-Ag, anti-HEV antibody and HEV RNA as well as the correlation analysis between HEV-Ag and HEV RNA. Results Twenty-six out of 36 340 plasma samples (0.07%) were positive for HEV-Ag. Of the 26 samples, 25 samples were positive for HEV RNA as indicated by the results of nested RT-PCR and 23 positive samples were confirmed by sequencing analysis. The positive rate of HEV RNA in blood plasma donators was 1∶1 580 (0.06%). There were 17 samples of genotype 1 (74%) and 6 samples of genotype 4 (26%) according to the phylogenetic tree analysis. All of the HEV-Ag positive samples were also positive for HEV RNA as indicated by the analysis of Biomex seroconversion panels. HEV-Ag was consistent with the peak of the HEV RNA concentration. Conclusion A close relationship between HEV-Ag and HEV RNA was observed. HEV-Ag screening could be used as a measure to reduce the risk of HEV transmission by blood transfusion. Key words: Hepatitis E virus (HEV); Antigen; RNA; Plasma

Hepatitis E Virus in the Countries of the Middle East and North Africa Region: An Awareness of an Infectious Threat to Blood Safety

Introduction: Hepatitis E virus (HEV) is mainly transmitted through contaminated water supplies which make the virus endemic in developing countries including countries of the Middle East and North Africa (MENA) region. Recent reports suggest potential risk of HEV transmission via blood transfusion particularly in endemic areas. Materials and Methods: Related articles on HEV were collected by searching through the 25 countries of the MENA region using Pubmed and Medline within the past 14 years: January 2000-August 2014. Results: One hundred articles were extracted, of which 25 were not eligible. The articles discussed the seroprevalence of HEV and HEV markers in 12 countries. Eight articles provided data on HEV in blood donors. The seroprevalence of HEV in the general MENA population ranged from 2.0%-37.5% and was higher in males than in females. Prevalence increased with age, but exposure seems to be in early life. Discussion: In the MENA region the role of HEV as an infectious threat to blood safety is under-investigated. More data are needed to quantify the risk of transmission and to assess clinical outcomes. This requires, at least, surveillance screening of donors and recipients for HEV markers using sensitive and specific serological tests. At the present time, serious consideration should be given to selective screening for certain groups of patients (e.g. immunocompromised, pregnant women and others) who commonly require blood transfusion and are at high risk of hepatic failure or chronicity from HEV infection.

Establishment of culture systems for Genotypes 3 and 4 hepatitis E virus (HEV) obtained from human blood and application of HEV inactivation using a pathogen reduction technology system

It has been demonstrated that the hepatitis E virus (HEV) can be transmitted via blood transfusion, and the risk of HEV transmission via transfusion has become a major global concern. An HEV culture system for blood-derived HEV has been sought to obtain valuable knowledge of the virus and the risk of HEV infection through blood products. We endeavored to establish an HEV culture system using RNA-positive blood specimens for Genotypes (G) 3 and 4 and applied this system to evaluate tissue culture infectious dose (TCID). We applied this method to investigate the potential of the Mirasol pathogen reduction technology (PRT) system (Terumo BCT) to inactivate live HEV in contaminated platelet samples (PLTs). PLTs were spiked with cultured HEV G3 or G4 and then treated with the Mirasol PRT system. PLTs were examined before and after the treatment for HEV load using TCID titration. We successfully established two strains for HEV production: the JRC-HE3 strain for G3 and the UA1 strain for G4. The Mirasol PRT system expressed more than 3 log inactivation for JRC-HE3 and more than 2 log inactivation for UA1. The Mirasol PRT system inactivated greater than 2 to 3 logs of live HEV in PLTs and can potentially be used to lower the possibility of blood-borne HEV transmission. The G3 and G4 HEV inocula identified in this study and the hepatoma cell culture system provide a new means to assess HEV infectious titer and to evaluate other pathogen reduction strategies.

Hepatitis E seroprevalence among blood donors: A pilot study from Western India

Background:Hepatitis E virus (HEV) is emerging as a potential threat to blood safety after several cases of transmission by transfusion or transplantation have been described. Currently, blood donors in India are not screened for HEV. The studies conducted on HEV in recent times in India have focused on epidemiology and future perspectives, but there is no published study on blood donors. To address possible issues surrounding blood safety and risk of HEV transmission within the Indian blood supply, HEV seroprevalence study was conducted in blood donors at our center.Materials and Methods:A total of 460 male voluntary blood donors were selected for the study and after taking their written consent. Serum anti-HEV IgM was detected by Dia.Pro HEV kit (Diagnostic Bioprobes Srl, Milano, Italy).Results:The study population was composed of 460 male voluntary blood donors and their age ranged from 18 to 60 years with a mean age of 30.48 years. Out of 460 donors, 22 (4.78%) donors were tested positive for IgM anti-HEV and the mean value alanine aminotransferase (ALT) was 26.06 IU/L, the highest being 93.5 IU/L. Normal reference value of ALT in our center was 40 IU/L. Out of 22 anti-HEV positive donors, 19 (86.36%) had ALT values above 40 IU/L.Conclusion:HEV seroprevalence of 4.78% in our center. Though reports of HEV transmission through blood has been reported from various parts of the world, before making it as a mandatory screening test among blood donors in India, further studies with confirmatory assay of HEV need to be done.