Nationwide survey of hepatitis E virus infection among wildlife in Japan

Imported Hepatitis E Virus Genotype 1: A Rare Case of Acute Hepatitis Managed with Steroid Pulse Therapy

A 26-year-old Indian man who had arrived in Japan 24 days prior presented to our hospital with abdominal pain and a fever. A blood test revealed marked hepatic dysfunction, and imaging tests confirmed a diagnosis of acute hepatitis. The patient's liver function and coagulability deteriorated, and his general condition was poor. Given the possibility of fulminant hepatic failure, we initiated steroid pulse therapy. Following the initiation of steroid therapy, the patient's liver function and subjective symptoms rapidly improved. Testing revealed positive findings for IgA-hepatitis E virus, and a genetic analysis of hepatitis E identified genotype 1, which is not endemic to Japan, leading to a definitive diagnosis of imported hepatitis E infection from India. The successful response to steroid therapy highlights the potential benefit of this approach in managing severe cases of acute hepatitis E, a rare occurrence in Japan. This case underscores the importance of considering hepatitis E infection in individuals with a recent travel history to regions with high prevalence and the potential benefits of steroid therapy in managing severe cases of acute hepatitis E.

Hepatitis A Virus and Hepatitis E Virus as Food- and Waterborne Pathogens-Transmission Routes and Methods for Detection in Food

Foodborne viruses are an important threat to food safety and public health. Globally, there are approximately 5 million cases of acute viral hepatitis due to hepatitis A virus (HAV) and hepatitis E virus (HEV) every year. HAV is responsible for numerous food-related viral outbreaks worldwide, while HEV is an emerging pathogen with a global health burden. The reported HEV cases in Europe have increased tenfold in the last 20 years due to its zoonotic transmission through the consumption of infected meat or meat products. HEV is considered the most common cause of acute viral hepatitis worldwide currently. This review focuses on the latest findings on the foodborne transmission routes of HAV and HEV and the methods for their detection in different food matrices.

Phylodynamic Analysis Suggests That Deer Species May Be a True Reservoir for Hepatitis E Virus Genotypes 3 and 4

Hepatitis E virus (HEV) genotypes 3 and 4 (HEV-3 and HEV-4) cause zoonotic infection in humans, with domestic pigs and wild boars being the main reservoirs of infection. Other than suids, HEV-3 and HEV-4 are found in ruminants, most frequently in deer species. However, it is still debatable, whether HEV infection in deer is a spillover, or indicates a stable virus circulation in these host species. To explore the patterns of HEV-3 and HEV-4 transmission in deer and other host species, we performed a Bayesian analysis of HEV sequences available in GenBank. A total of 27 HEV sequences from different deer species were found in GenBank. Sequences from wild boars collected in the same territories, as well as sequences from all mammals that were most similar to sequences from deer in blast search, were added to the dataset, comprising 617 in total sequences. Due to the presence of partial genomic sequences, they were divided into four subsets (two ORF1 fragments and two ORF2 fragments) and analyzed separately. European HEV-3 sequences and Asian HEV-4 sequences collected from deer species demonstrated two transmission patterns. The first pattern was spillover infection, and the second pattern was deer-to-deer transmission, indicating stable HEV circulation in these species. However, all geographic HEV clusters that contained both deer and swine sequences originated from ancestral swine strains. HEV-3 and HEV-4 transmission patterns in ungulates reconstructed by means of Bayesian analysis indicate that deer species are a true host for HEV. However, wild and domestic swine are often the primary source of infection for ruminants living in the same areas. Complete HEV genomic sequences from different parts of the world are crucial for further understanding the HEV-3 and HEV-4 circulation patterns in wildlife.

Current Knowledge of Hepatitis E Virus (HEV) Epidemiology in Ruminants

Hepatitis E virus (HEV) infection represents an emerging public health concern worldwide. In industrialized countries, increasing numbers of autochthonous cases of human HEV infection are caused by zoonotic transmission of genotypes 3 and 4, mainly through the consumption of contaminated raw or undercooked meat of infected pigs and wild boars, which are considered the main reservoirs of HEV. However, in the last few years, accumulating evidence seems to indicate that several other animals, including different ruminant species, may harbor HEV. Understanding the impact of HEV infection in ruminants and identifying the risk factors affecting transmission among animals and to humans is critical in order to determine their role in the epidemiological cycle of HEV. In this review, we provide a summary of current knowledge on HEV ecology in ruminants. A growing body of evidence has revealed that these animal species may be potential important hosts of HEV, raising concerns about the possible implications for public health.