Novel hepatitis E like virus found in Swedish moose

A novel virus was detected in a sample collected from a Swedish moose (Alces alces). The virus was suggested as a member of the Hepeviridae family, although it was found to be highly divergent from the known four genotypes (gt1–4) of hepatitis E virus (HEV). Moose are regularly hunted for consumption in the whole of Scandinavia. Thus, the finding of this virus may be important from several aspects: (a) as a new diverged HEV in a new animal species, and (b) potential unexplored HEV transmission pathways for human infections. Considering these aspects, we have started the molecular characterization of this virus. A 5.1 kb amplicon was sequenced, and corresponded to the partial ORF1, followed by complete ORF2, ORF3 and poly(A) sequence. In comparison with existing HEVs, the moose HEV genome showed a general nucleotide sequence similarity of 37–63 % and an extensively divergent putative ORF3 sequence. The junction region between the ORFs was also highly divergent; however, two putative secondary stem–loop structures were retained when compared to gt1–4, but with altered structural appearance. In the phylogenetic analysis, the moose HEV deviated and formed its own branch between the gt1–4 and other divergent animal HEVs. The characterization of this highly divergent genome provides important information regarding the diversity of HEV infecting various mammalian species. However, further studies are needed to investigate its prevalence in the moose populations and possibly in other host species, including the risk for human infection.

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Genetic identification and characterization of a novel virus related to human hepatitis E virus from chickens with hepatitis–splenomegaly syndrome in the United States

Journal of General Virology ◽

10.1099/0022-1317-82-10-2449 ◽

2001 ◽

Vol 82 (10) ◽

pp. 2449-2462 ◽

Cited By ~ 242

Author(s):

G. Haqshenas ◽

H. L. Shivaprasad ◽

P. R. Woolcock ◽

D. H. Read ◽

X. J. Meng

Keyword(s):

Hepatitis E Virus ◽

Hepatitis E ◽

Rdrp Gene ◽

Genetic Identification ◽

Helicase Gene ◽

Novel Virus ◽

Avian Hev ◽

Identification And Characterization ◽

Sequence Identities

Hepatitis–splenomegaly (HS) syndrome is an emerging disease in chickens in North America; the cause of this disease is unknown. In this study, the genetic identification and characterization of a novel virus related to human hepatitis E virus (HEV) isolated from bile samples of chickens with HS syndrome is reported. Based upon the similar genomic organization and significant sequence identity of this virus with HEV, the virus has been tentatively named avian HEV in order to distinguish it from human and swine HEV. Electron microscopy revealed that avian HEV is a non-enveloped virus particle of 30–35 nm in diameter. The sequence of the 3′ half of the viral genome (∼4 kb) was determined. Sequence analyses revealed that this genomic region contains the complete 3′ non-coding region, the complete genes from open reading frames (ORFs) 2 and 3, the complete RNA-dependent RNA polymerase (RdRp) gene and a partial helicase gene from ORF 1. The helicase gene is the most conserved gene between avian HEV and other HEV strains, displaying 58–61% aa and 57–60% nt sequence identities. The RdRp gene of avian HEV shares 47–50% aa and 52–53% nt sequence identities and the putative capsid gene (ORF 2) of avian HEV shares 48–49% aa and 48–51% nt sequence identities with the corresponding regions of other known HEV strains. Phylogenetic analysis indicates that avian HEV is genetically related to, but distinct from, other known HEV strains. This discovery has important implications for HEV animal models, nomenclature and natural history.

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A novel avian isolate of hepatitis E virus from Pakistan

Virology Journal ◽

10.1186/s12985-019-1247-0 ◽

2019 ◽

Vol 16 (1) ◽

Cited By ~ 1

Author(s):

Tahir Iqbal ◽

Umer Rashid ◽

Muhammad Idrees ◽

Amber Afroz ◽

Saleem Kamili ◽

...

Keyword(s):

Amino Acid ◽

Structure Prediction ◽

Hepatitis E Virus ◽

Secondary Structure Prediction ◽

Clinical Symptoms ◽

Sequence Similarity ◽

Evolutionary Genetics ◽

Hepatitis E ◽

Stem Loop ◽

Layer Chickens

Abstract Background Avian hepatitis E virus (aHEV) has been associated with hepatitis-splenomegaly syndrome (HSS) in chickens along with asymptomatic subclinical infection in many cases. So far, four genotypes have been described, which cause infection in chickens, specifically in broiler breeders and layer chickens. In the present study, we isolated and identified two novel aHEV strains from the bile of layer chickens in Pakistan evincing clinical symptoms related to HSS. Methodology Histology of liver and spleen tissues was carried out to observe histopathological changes in these tissues. Bile fluid and fecal suspensions were used for viral RNA isolation through MegNA pure and Trizol method which was further used for viral genome detection and characterization by cDNA synthesis and amplification of partial open reading frame (ORF) 1, ORF2 and complete ORF3. The bioinformatics tools; Molecular Evolutionary Genetics Analysis version 6.0 (MEGA 6), Mfold and ProtScale were used for phylogenic analysis, RNA secondary structure prediction and protein hydropathy analysis, respectively. Results Sequencing and phylogenetic analysis on the basis of partial methyltranferase (MeT), helicase (Hel) domain, ORF2 and complete ORF3 sequence suggests these Pakistani aHEV (Pak aHEV) isolates may belong to a Pakistani specific clade. The overall sequence similarity between the Pak aHEV sequences was 98–100%. The ORF1/ORF3 intergenic region contains a conserved cis-reactive element (CRE) and stem-loop structure (SLS). Analysis of the amino acid sequence of ORF3 indicated two hydrophobic domains (HD) and single conserved proline-rich domain (PRD) PREPSAPP (PXXPXXPP) with a single PSAP motif found in C-terminal. Amino acid changes S15 T, A31T, Q35H and G46D unique to the Pak aHEV sequences were found in the N-terminal region of ORF3. Conclusions Our data suggests that Pak aHEV isolates may represent a novel Pakistani clade and high sequence homology to each other support the supposition they may belong to a monophyletic clade circulating in the region around Pakistan. The data presented in this study provide further information for aHEV genetic diversity, genotype mapping, global distribution and epidemiology.

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Antigenic Characterization of ORF2 and ORF3 Proteins of Hepatitis E Virus (HEV)

Viruses ◽

10.3390/v13071385 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1385

Author(s):

Giulia Pezzoni ◽

Lidia Stercoli ◽

Eleonora Pegoiani ◽

Emiliana Brocchi

Keyword(s):

Hepatitis E Virus ◽

Hepatitis E ◽

Recombinant Antigen ◽

Open Reading Frame ◽

Reading Frame ◽

E Coli ◽

Antigenic Characterization ◽

Antigenic Properties ◽

Open Reading Frame 2

To evaluate the antigenic properties of Hepatitis E Virus (HEV) Open Reading Frame 2 and 3 (ORF2 and ORF3) codified proteins, we expressed different portions of ORF2 and the entire ORF3 in E. coli, a truncated ORF2, was also expressed in baculovirus. A panel of 37 monoclonal antibodies (MAbs) was raised against ORF2 (1–660 amino acids) and MAbs were mapped and characterized using the ORF2 expressed portions. Selected HEV positive and negative swine sera were used to evaluate ORF2 and ORF3 antigens’ immunogenicity. The MAbs were clustered in six groups identifying six antigenic regions along the ORF2. Only MAbs binding to the sixth ORF2 antigenic region (394–608 aa) were found to compete with HEV positive sera and efficiently catch the recombinant antigen expressed in baculovirus. The ORF2 portion from 394–608 aa demonstrated to include most immunogenic epitopes with 85% of HEV positive swine sera reacting against the region from 461–544 aa. Only 5% of the selected HEV sera reacted against the ORF3 antigen.

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First molecular detection of hepatitis E virus genome in camel and pig faecal samples in Ethiopia

Virology Journal ◽

10.1186/s12985-021-01626-9 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Fufa Dawo Bari ◽

Haimanot Belete Wodaje ◽

Umer Said ◽

Hika Waktole ◽

Melaku Sombo ◽

...

Keyword(s):

Public Health ◽

Hepatitis E Virus ◽

Addis Ababa ◽

Hepatitis E ◽

Human Infection ◽

Health Concern ◽

Universal Primers ◽

Viral Gene ◽

Public Health Importance ◽

Faecal Samples

Abstract Background Hepatitis E is an enteric and zoonotic disease caused by hepatitis E virus (HEV) that is mainly transmitted via the faecal-oral route through contaminated food or the environment. The virus is an emerging infectious agent causing acute human infection worldwide. A high seroprevalence of the disease was reported in pregnant women in Addis Ababa, Ethiopia, raising significant public health concern. The presence of HEV specific antibodies were also reported in dromedary camels in the country; however, the infectious virus and/or the viral genome have not been demonstrated to date in animal samples. Methods To address this gap, a total of 95 faecal samples collected from both apparently healthy pigs of uncharacterised types (50 samples) in Burayu and Addis Ababa areas and camels (Camelus dromedarius, 45 samples) in west Hararghe were screened for the presence of HEV genome using universal primers in a fully nested reverse transcription polymerase chain reaction (nRT-PCR). The protocol is capable of detecting HEV in faecal samples from both pigs and camels. Results The nRT-PCR detected HEV genes in six (12%) pig faecal samples and one camel sample (2.2%). Therefore, the results indicate that HEV is circulating in both pigs and camels in Ethiopia and these animals and their products could serve as a potential source of infection for humans. Conclusion The detection of HEV in both animals could raise another concern regarding its public health importance as both animals’ meat and camel milk are consumed in the country. Further studies to determine the prevalence and distribution of the virus in different animals and their products, water bodies, food chain, and vegetables are warranted, along with viral gene sequencing for detailed genetic characterisation of the isolates circulating in the country. This information is critically important to design and institute appropriate control and/or preventive measures.

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