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1.
Viruses ; 13(9)2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34578311

RESUMO

The sole member of the Piscihepevirus genus (family Hepeviridae) is cutthroat trout virus (CTV) but recent metatranscriptomic studies have identified numerous fish hepevirus sequences including CTV-2. In the current study, viruses with sequences resembling both CTV and CTV-2 were isolated from salmonids in eastern and western Canada. Phylogenetic analysis of eight full genomes delineated the Canadian CTV isolates into two genotypes (CTV-1 and CTV-2) within the Piscihepevirus genus. Hepevirus genomes typically have three open reading frames but an ORF3 counterpart was not predicted in the Canadian CTV isolates. In vitro replication of a CTV-2 isolate produced cytopathic effects in the CHSE-214 cell line with similar amplification efficiency as CTV. Likewise, the morphology of the CTV-2 isolate resembled CTV, yet viral replication caused dilation of the endoplasmic reticulum lumen which was not previously observed. Controlled laboratory studies exposing sockeye (Oncorhynchus nerka), pink (O. gorbuscha), and chinook salmon (O. tshawytscha) to CTV-2 resulted in persistent infections without disease and mortality. Infected Atlantic salmon (Salmo salar) and chinook salmon served as hosts and potential reservoirs of CTV-2. The data presented herein provides the first in vitro and in vivo characterization of CTV-2 and reveals greater diversity of piscihepeviruses extending the known host range and geographic distribution of CTV viruses.


Assuntos
Doenças dos Peixes/virologia , Hepevirus/classificação , Hepevirus/genética , Hepevirus/isolamento & purificação , Animais , Canadá , Genótipo , Hepevirus/patogenicidade , Infecção Persistente/virologia , Filogenia , Salmo salar/virologia , Salmão/virologia , Truta , Virulência , Vírus não Classificados/classificação , Vírus não Classificados/genética , Vírus não Classificados/isolamento & purificação , Vírus não Classificados/patogenicidade
2.
Viruses ; 13(6)2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064072

RESUMO

Avian hepatitis E virus (aHEV) is the major etiological agent of hepatitis-splenomegaly syndrome (HSS), big liver and spleen disease (BLSD), and hepatic rupture hemorrhage syndrome (HRHS) in chickens. Infections with aHEV cause a significant decrease in egg production and increased mortality in chickens worldwide. However, studies on the prevalence of aHEV in Nigeria are scarce. In this study, serum (n = 88) and fecal samples (n = 110) obtained from apparently healthy layer chickens from three states in southwestern Nigeria were analyzed by nested reverse transcription-polymerase chain reaction (nRT-PCR) targeting the helicase and capsid gene for the presence of aHEV. Avian HEV was detected in 12.5% (n = 11/88) of serum samples and 9.1% (n = 10/110) of fecal samples tested. Phylogenetic analysis showed that five of the twelve identified aHEV sequences belonged to genotype 2. The remaining seven sequences were only distantly related to other known aHEV isolates. After amplification of the near-complete ORF2 fragment (1618 bp) and part of the ORF1 (582 bp) of isolate YF40_aHEV_NG phylogenetic analysis revealed a nucleotide sequence identity between 79.0 and 82.6% and 80.1 and 83.5%, respectively, to other known aHEV strains, indicating that the Nigerian isolate YF40_aHEV_NG belongs to a novel aHEV genotype. This is the first report of co-circulation of aHEV genotypes in chickens in Nigeria.


Assuntos
Galinhas , Genoma Viral , Genótipo , Hepatite Viral Animal/virologia , Hepevirus/classificação , Doenças das Aves Domésticas/virologia , Infecções por Vírus de RNA/veterinária , Animais , Hepatite Viral Animal/epidemiologia , Hepevirus/genética , Hepevirus/isolamento & purificação , Nigéria/epidemiologia , Fases de Leitura Aberta , Filogenia , Doenças das Aves Domésticas/epidemiologia , RNA Viral
3.
Infect Genet Evol ; 93: 104942, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34044191

RESUMO

Rodents including rats are reservoir of several pathogens capable of affecting human health. In this study, faecal and different organ specimens from free-living Norway rats (Rattus norvegicus) (N = 18) and faecal samples from laboratory rodents (rats N = 21 and mice N = 20) collected from different geographic areas in Hungary between 2017 and 2020 were investigated by viral metagenomics and conventional RT-PCR methods. The complete genome of three different RNA viruses, rat astrovirus, rat norovirus and rat hepevirus were characterized and analysed in detail. Rat norovirus was detected in faecal (17.6%, 3/17) and kidney (7.1%, 1/14) samples; rat astrovirus in faecal (23.5%, 4/17) and spleen (13.3%, 2/15) samples, and rat hepevirus in 43% to 67% the faecal, liver, kidney, lung, heart, muscle, brain and blood samples from Norway rats, respectively. Rat norovirus was also identifiable in 5% (1/21) of laboratory rats and rat astrovirus in 40% (8/20) of faecal samples from laboratory mice. Co-infections were found in 28% (5/18) wild Norway rats. The highest RNA viral load of astrovirus (1.81 × 108 copy/g) and norovirus (3.49 × 107 copy/g) were measured in faecal samples; while the highest RNA viral load of hepevirus (1.16 × 109 copy/g) was found in liver samples of Norway rats, respectively. This study confirms the wide geographic distribution and high prevalence of astrovirus, norovirus and hepevirus among wild rats in Hungary with confirmation of different organ involvement of as well as the detection of norovirus and astrovirus in laboratory rats and mice, respectively. This finding further strengthens the role of rodents in the spread of viral pathogens especially infecting human.


Assuntos
Astroviridae/isolamento & purificação , Hepevirus/isolamento & purificação , Camundongos , Norovirus/isolamento & purificação , Ratos , Doenças dos Roedores/epidemiologia , Animais , Animais de Laboratório , Animais Selvagens , Astroviridae/genética , Infecções por Astroviridae/epidemiologia , Infecções por Astroviridae/veterinária , Infecções por Astroviridae/virologia , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/veterinária , Infecções por Caliciviridae/virologia , Hepatite Viral Animal/epidemiologia , Hepatite Viral Animal/virologia , Hepevirus/genética , Hungria/epidemiologia , Norovirus/genética , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/veterinária , Infecções por Vírus de RNA/virologia , Doenças dos Roedores/virologia
4.
Viruses ; 12(3)2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192159

RESUMO

The family Hepeviridae includes several positive-stranded RNA viruses, which infect a wide range of mammalian species, chicken, and trout. However, few hepatitis E viruses (HEVs) have been characterized from invertebrates. In this study, a hepevirus, tentatively named Crustacea hepe-like virus 1 (CHEV1), from the economically important crustacean, the giant freshwater prawn Macrobrachium rosenbergii, was characterized. The complete genome consisted of 7750 nucleotides and had a similar structure to known hepatitis E virus genomes. Phylogenetic analyses suggested it might be a novel hepe-like virus within the family Hepeviridae. To our knowledge, this is the first hepe-like virus characterized from crustaceans.


Assuntos
Hepevirus/classificação , Hepevirus/genética , Palaemonidae/virologia , Doenças dos Animais/virologia , Animais , Água Doce , Genoma Viral , Genômica/métodos , Hepevirus/isolamento & purificação , Fases de Leitura Aberta , Filogenia , RNA Viral
5.
Arch Virol ; 164(11): 2671-2682, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31399875

RESUMO

Rodents host different orthohepeviruses, namely orthohepevirus C genotype HEV-C1 (rat hepatitis E virus, HEV) and the additional putative genotypes HEV-C3 and HEV-C4. Here, we screened 2,961 rodents from Central Europe by reverse transcription polymerase chain reaction (RT-PCR) and identified HEV RNA in 13 common voles (Microtus arvalis) and one bank vole (Myodes glareolus) with detection rates of 2% (95% confidence interval [CI]: 1-3.4) and 0.08% (95% CI: 0.002-0.46), respectively. Sequencing of a 279-nucleotide RT-PCR amplicon corresponding to a region within open reading frame (ORF) 1 showed a high degree of similarity to recently described common vole-associated HEV (cvHEV) sequences from Hungary. Five novel complete cvHEV genome sequences from Central Europe showed the typical HEV genome organization with ORF1, ORF2 and ORF3 and RNA secondary structure. Uncommon features included a noncanonical start codon in ORF3, multiple insertions and deletions within ORF1 and ORF2/ORF3, and the absence of a putative ORF4. Phylogenetic analysis showed all of the novel cvHEV sequences to be monophyletic, clustering most closely with an unassigned bird-derived sequence and other sequences of the species Orthohepevirus C. The nucleotide and amino acid sequence divergence of the common vole-derived sequences was significantly correlated with the spatial distance between the trapping sites, indicating mostly local evolutionary processes. Detection of closely related HEV sequences in common voles in multiple localities over a distance of 800 kilometers suggested that common voles are infected by cvHEV across broad geographic distances. The common vole-associated HEV strain is clearly divergent from HEV sequences recently found in narrow-headed voles (Microtus gregalis) and other cricetid rodents.


Assuntos
Arvicolinae/virologia , Hepatite Viral Animal/virologia , Hepevirus/classificação , Hepevirus/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Europa (Continente) , Genoma Viral/genética , Hepevirus/isolamento & purificação , Fases de Leitura Aberta/genética
6.
Arch Virol ; 164(2): 595-599, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30392050

RESUMO

Big liver and spleen disease, caused by avian hepatitis E virus, has been reported in Poland, but the prevalence of the virus has not yet been investigated. In this study, 1034 serum samples from 57 breeder broiler and laying hen flocks were screened for the presence of anti-aHEV antibodies. In a random serology study, 56.1% of flocks were positive. Seroprevalence was higher in laying hen flocks than in broiler breeder flocks. Phylogenetic analysis of partial ORF1 and ORF2 sequences revealed that all Polish isolates belonged to genotype 2. This is the first time this genotype has been detected in Central Europe.


Assuntos
Hepatite Viral Animal/virologia , Hepevirus/isolamento & purificação , Doenças das Aves Domésticas/virologia , Animais , Anticorpos Antivirais/sangue , Galinhas , Feminino , Genótipo , Hepatite Viral Animal/sangue , Hepatite Viral Animal/epidemiologia , Hepevirus/classificação , Hepevirus/genética , Hepevirus/imunologia , Masculino , Filogenia , Polônia/epidemiologia , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/epidemiologia , Estudos Soroepidemiológicos
8.
Virus Res ; 250: 81-86, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29605729

RESUMO

A novel virus was identified in the white-backed planthopper (Sogatella furcifera, Hemiptera: Delphacidae) and tentatively named Sogatella furcifera hepe-like virus (SfHeV). Its genome is a linear, single-stranded monopartite RNA, 7,312 nucleotides (nt) long with a 66-nt 5' UTR, 54-nt 3' UTR, and 28-nt polyA, showing typical genomic features of viruses in the family Hepeviridae, but highly divergent from known members in the family, with amino acid sequence identities of only 18.9-23% (ORF1), 13.1-18.8% (ORF2) and 1.9-11% (ORF3). Phylogenetic analysis revealed that SfHeV was closer to cutthroat trout virus (CTV), but did not cluster with any members of the family. SfHeV is the first hepe-like virus identified in a hemipteran insect and was detected in all developmental stages suggesting the presence of some level of vertical transmission. On the basis of these data, we propose that SfHeV represents a novel clade in the family Hepeviridae and tentatively name the genus Insecthepevirus.


Assuntos
Hemípteros/virologia , Hepevirus/classificação , Animais , Hepevirus/genética , Hepevirus/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , RNA Viral/genética
9.
Virol Sin ; 33(1): 44-58, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29500690

RESUMO

Hepatitis E virus (HEV) is the prototype of the family Hepeviridae and the causative agent of common acute viral hepatitis. Genetically diverse HEV-related viruses have been detected in a variety of mammals and some of them may have zoonotic potential. In this study, we tested 278 specimens collected from seven wild small mammal species in Yunnan province, China, for the presence and prevalence of orthohepevirus by broad-spectrum reverse transcription (RT)-PCR. HEV-related sequences were detected in two rodent species, including Chevrier's field mouse (Apodemus chevrieri, family Muridae) and Père David's vole (Eothenomys melanogaster, family Cricetidae), with the infection rates of 29.20% (59/202) and 7.27% (4/55), respectively. Further four representative full-length genomes were generated: two each from Chevrier's field mouse (named RdHEVAc14 and RdHEVAc86) and Père David's vole (RdHEVEm40 and RdHEVEm67). Phylogenetic analyses and pairwise distance comparisons of whole genome sequences and amino acid sequences of the gene coding regions showed that orthohepeviruses identified in Chinese Chevrier's field mouse and Père David's vole belonged to the species Orthohepevirus C but were highly divergent from the two assigned genotypes: HEV-C1 derived from rat and shrew, and HEV-C2 derived from ferret and possibly mink. Quantitative real-time RT-PCR demonstrated that these newly discovered orthohepeviruses had hepatic tropism. In summary, our work discovered two putative novel genotypes orthohepeviruses preliminarily named HEV-C3 and HEV-C4 within the species Orthohepevirus C, which expands our understanding of orthohepevirus infection in the order Rodentia and gives new insights into the origin, evolution, and host range of orthohepevirus.


Assuntos
Arvicolinae/virologia , Variação Genética , Hepatite Viral Animal/virologia , Hepevirus/classificação , Hepevirus/isolamento & purificação , Murinae/virologia , Infecções por Vírus de RNA/veterinária , Animais , China , Genótipo , Hepatite Viral Animal/epidemiologia , Hepevirus/genética , Hepevirus/fisiologia , Programas de Rastreamento , Filogenia , Prevalência , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Tropismo Viral , Sequenciamento Completo do Genoma
10.
Vet Microbiol ; 203: 174-180, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28619140

RESUMO

To determine the relationship between decreased egg production and avian HEV infection, thirty healthy 23-week-old Hy-Line Variety Brown layer hens were randomly divided into 3 groups with 10 hens per group. Next, a genotype 3 avian HEV strain from China was used to inoculate laying hens via oronasal or intravenous routes using a 50% chicken infectious dose of 500. All hens were necropsied at 14 weeks postinoculation (wpi). Fecal virus shedding, viremia, seroconversion, serum alanine aminotransferase (ALT) increases and liver lesions showed that after intravenous (i.v.) and oronasal inoculation, the laying hens were successfully infected. Compared with the uninoculated group, the i.v. and oronasally inoculated groups exhibited egg production decreases at 1wpi and 2wpi, reaching peak production at 3wpi and 8wpi, respectively. In both groups, decreased production was evident for 12 weeks and overall decreases ranged from 10% to 30%. In addition, in the 7 field layer farms exhibiting decreased egg production, vaccination regimens had been completed against Newcastle disease, infectious bronchitis, avian influenza H9N2 and H5N1 and egg drop syndrome virus. However, circulating avian HEV was confirmed on these farms using tests to detect avian HEV IgG antibodies and RNA. Therefore, the experimental and field data indicate that avian HEV infection acting alone could account for observed decreases in egg production in laying hens.


Assuntos
Galinhas/virologia , Hepatite Viral Animal/virologia , Hepevirus/patogenicidade , Infecções por Vírus de RNA/veterinária , Animais , China , Ovos , Feminino , Genótipo , Hepevirus/genética , Hepevirus/isolamento & purificação , Infecções por Vírus de RNA/virologia , Eliminação de Partículas Virais
11.
Ann Intern Med ; 167(1): 1-7, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28586923

RESUMO

BACKGROUND: Next-generation metagenomic sequencing (NGMS) has opened new frontiers in microbial discovery but has been clinically characterized in only a few settings. OBJECTIVE: To explore the plasma virome of persons who inject drugs and to characterize the sensitivity and accuracy of NGMS compared with quantitative clinical standards. DESIGN: Longitudinal and cross-sectional studies. SETTING: A clinical trial (ClinicalTrials.gov: NCT01285050) and a well-characterized cohort study of persons who have injected drugs. PARTICIPANTS: Persons co-infected with hepatitis C virus (HCV) and HIV. MEASUREMENTS: Viral nucleic acid in plasma by NGMS and quantitative polymerase chain reaction (PCR). RESULTS: Next-generation metagenomic sequencing generated a total of 600 million reads, which included the expected HIV and HCV RNA sequences. HIV and HCV reads were consistently identified only when samples contained more than 10 000 copies/mL or IU/mL, respectively, as determined by quantitative PCR. A novel RNA virus, human hepegivirus-1 (HHpgV-1), was also detected by NGMS in 4 samples from 2 persons in the clinical trial. Through use of a quantitative PCR assay for HHpgV-1, infection was also detected in 17 (10.9%) of 156 members of a cohort of persons who injected drugs. In these persons, HHpgV-1 viremia persisted for a median of at least 4538 days and was associated with detection of other bloodborne viruses, such as HCV RNA and SEN virus D. LIMITATION: The medical importance of HHpgV-1 infection is unknown. CONCLUSION: Although NGMS is insensitive for detection of viruses with relatively low plasma nucleic acid concentrations, it may have broad potential for discovery of new viral infections of possible medical importance, such as HHpgV-1. PRIMARY FUNDING SOURCE: National Institutes of Health.


Assuntos
Infecções por HIV/virologia , Hepatite C/virologia , Hepevirus/isolamento & purificação , Abuso de Substâncias por Via Intravenosa/virologia , Viremia/diagnóstico , Coinfecção , Estudos Transversais , Feminino , Biblioteca Genômica , Infecções por HIV/complicações , Hepatite C/complicações , Hepevirus/genética , Humanos , Estudos Longitudinais , Masculino , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Análise de Sequência de RNA
12.
Virol J ; 14(1): 40, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28222808

RESUMO

BACKGROUND: In recent years, novel hepadnaviruses, hepeviruses, hepatoviruses, and hepaciviruses have been discovered in various species of bat around the world, indicating that bats may act as natural reservoirs for these hepatitis viruses. In order to further assess the distribution of hepatitis viruses in bat populations in China, we tested the presence of these hepatitis viruses in our archived bat liver samples that originated from several bat species and various geographical regions in China. METHODS: A total of 78 bat liver samples (involving two families, five genera, and 17 species of bat) were examined using nested or heminested reverse transcription PCR (RT-PCR) with degenerate primers. Full-length genomic sequences of two virus strains were sequenced followed by phylogenetic analyses. RESULTS: Four samples were positive for hepadnavirus, only one was positive for hepevirus, and none of the samples were positive for hepatovirus or hepacivirus. The hepadnaviruses were discovered in the horseshoe bats, Rhinolophus sinicus and Rhinolophus affinis, and the hepevirus was found in the whiskered bat Myotis davidii. The full-length genomic sequences were determined for one of the two hepadnaviruses identified in R. sinicus (designated BtHBVRs3364) and the hepevirus (designated BtHEVMd2350). A sequence identity analysis indicated that BtHBVRs3364 had the highest degree of identity with a previously reported hepadnavirus from the roundleaf bat, Hipposideros pomona, from China, and BtHEVMd2350 had the highest degree of identity with a hepevirus found in the serotine bat, Eptesicus serotinus, from Germany, but it exhibited high levels of divergence at both the nucleotide and the amino acid levels. CONCLUSIONS: This is the first study to report that the Chinese horseshoe bat and the Chinese whiskered bat have been found to carry novel hepadnaviruses and a novel hepevirus, respectively. The discovery of BtHBVRs3364 further supports the significance of host switches evolution while opposing the co-evolutionary theory associated with hepadnaviruses. According to the latest criterion of the International Committee on Taxonomy of Viruses (ICTV), we hypothesize that BtHEVMd2350 represents an independent genotype within the species Orthohepevirus D of the family Hepeviridae.


Assuntos
Quirópteros/virologia , Hepadnaviridae/classificação , Hepadnaviridae/isolamento & purificação , Hepevirus/classificação , Hepevirus/isolamento & purificação , Fígado/virologia , Filogenia , Animais , China , Análise por Conglomerados , Genoma Viral , Hepadnaviridae/genética , Hepevirus/genética , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
13.
Avian Dis ; 60(3): 698-704, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27610734

RESUMO

In the present study, avian hepatitis E virus (HEV) and serotype-1 strains of Marek's disease virus (MDV-1) were detected from a flock of 27-wk-old brown layer hens in China, accompanied by an average daily mortality of 0.44%. Postmortem examination of 25 sick hens and five apparently healthy hens selected randomly from the flock showed significant pathologic changes consistent with hepatitis-splenomegaly syndrome (HSS), including hepatomegaly, peritoneal fluid, and hepatic subcapsular hemorrhages. Microscopic examination of these livers showed multifocal necrotizing hepatitis and mild lymphocytic infiltration. These liver samples were investigated for HEV by reverse-transcription PCR. The overall detection rate of HEV RNA in samples of sick chickens was about 56% (14/25), while in samples from apparently healthy hens, it was 80% (4/5). Sequencing analysis of three 242-base-pair fragments of the helicase gene revealed 95.5% to 97.9% nucleotide identity compared with published avian HEV genotype 3, whereas identities demonstrated only 77.3% to 86.0% similarity when compared with genotypes 1, 2, and 4. Unexpectedly, the MDV meq gene was detected in livers from both apparently healthy chickens (2/5) and sick chickens (12/25) by PCR analysis. The meq gene (396 base pairs) was determined to belong to MDV-1 by further sequencing. The co-infection rate of avian HEV and MDV in this flock was 30% (9/30). This is the first report of dual infection of a nonenvelope RNA virus (HEV) with a herpesvirus (MDV) in chickens in China.


Assuntos
Galinhas , Coinfecção/veterinária , Doenças das Aves Domésticas/epidemiologia , Animais , Sequência de Bases , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/virologia , Feminino , Hepatite Viral Animal/epidemiologia , Hepatite Viral Animal/virologia , Hepevirus/isolamento & purificação , Herpesvirus Galináceo 2/isolamento & purificação , Doença de Marek/epidemiologia , Doença de Marek/virologia , Doenças das Aves Domésticas/virologia , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/veterinária , Infecções por Vírus de RNA/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
14.
Avian Dis ; 59(3): 388-93, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26478157

RESUMO

Between 2012 and 2014, 141 chickens from 10 organic layer flocks with a history of severe drop in egg production (up to 40%) and slight increased mortality (up to 1% per week) were submitted to the Avian Health and Food Safety Laboratory (Puyallup, WA). At necropsy, the most common finding was pinpoint white foci on the liver and regressed ova without any other remarkable lesions. Histologically, there was multifocal mild-to-severe acute necrotizing hepatitis present. No significant bacteria were recovered from liver samples, and tests for mycotoxins were negative. Twenty-six serum samples from four affected flocks tested were positive for avian hepatitis E virus (HEV) immunoglobulin Y antibodies. Avian HEV RNA was detected in 10 livers of chickens from two different affected flocks. The avian HEV was characterized by sequencing and determined to belong to genotype 2. The diagnosis of a clinical manifest HEV was based solely on the demonstration of specific viral RNA and the absence of other causative agents in samples from flocks, as the clinical sings and pathologic lesions were atypical.


Assuntos
Galinhas , Hepatite Viral Animal/virologia , Hepevirus/isolamento & purificação , Doenças das Aves Domésticas/virologia , Infecções por Vírus de RNA/veterinária , Envelhecimento , Criação de Animais Domésticos , Animais , Feminino , Hepatite Viral Animal/patologia , Hepevirus/genética , Oviposição , Filogenia , Doenças das Aves Domésticas/patologia , Infecções por Vírus de RNA/virologia
15.
BMC Vet Res ; 11: 195, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26260476

RESUMO

BACKGROUND: Avian hepatitis E virus (HEV) is the main causative agent of big liver and spleen disease, as well as hepatitis-splenomegaly syndrome in chickens. To date, conventional reverse transcriptase polymerase chain reaction (RT-PCR) and nested RT-PCR methods have been used for the diagnosis of avian HEV infection in chickens. However, these assays are time consuming, inconvenient, and cannot detect the virus quantitatively. In this study, a rapid and sensitive SYBR Green real-time RT-PCR assay was developed to detect avian HEV RNA quantitatively in serum, liver, spleen, and fecal samples from chickens. RESULTS: Based on the sequence of the most conserved HEV gene, ORF3, the primers for the assay were designed, and the standard plasmid was constructed. The detection limit of the assay was shown to be 10 copies/µl of standard plasmid/reaction, with a corresponding cycle-threshold value of 29.3. The standard curve exhibited a dynamic linear range across at least 7 log units of DNA copy number. The specificity and reproducibility of this assay was high, showing that the assay detected avian HEV RNA specifically and with little variability. Compared to conventional RT-PCR, the current assay is more sensitive for detecting avian HEV in serum, liver, spleen, and fecal samples from chickens. CONCLUSIONS: A rapid, specific, and reproducible SYBR Green real-time RT-PCR assay was developed for the diagnosis of avian HEV infection in chickens. This assay can accurately detect avian HEV RNA in serum, liver, spleen, and fecal samples with more sensitivity than conventional RT-PCR.


Assuntos
Hepatite Viral Animal/virologia , Hepevirus/isolamento & purificação , Doenças das Aves Domésticas/virologia , Infecções por Vírus de RNA/veterinária , Animais , Benzotiazóis , Galinhas , Diaminas , Regulação Viral da Expressão Gênica/fisiologia , Hepatite Viral Animal/diagnóstico , Compostos Orgânicos , Doenças das Aves Domésticas/diagnóstico , Quinolinas , Infecções por Vírus de RNA/diagnóstico , Infecções por Vírus de RNA/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos , Proteínas Virais/genética , Proteínas Virais/metabolismo
16.
J Virol Methods ; 214: 25-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25528997

RESUMO

Hepatitis E virus (HEV) infection is a public health concern worldwide, associated with waterborne outbreaks in developing countries and reported as an emerging zoonotic infection in high-income countries. A recent consensus proposal classified the isolates from human, swine, wild boar, deer, mongoose, rabbit and camel in seven genotypes within the species Orthohepevirus A. In this report a popular HEV RT-qPCR assay was assessed for the detection of the species Orthohepevirus A. In silico analysis of 189 complete genome sequences showed that the assay targets a highly conserved region in the Orthohepevirus A genome. Additionally, plasmid standards were constructed to test the effect of probe- and primer-binding site mutations in the assay performance. The assay proved robust enough to detect strains with mutations in the probe-binding site and in the 3' end primer-binding site regions. A degenerate version of the reverse primer improves the performance of the assay particularly in the detection of HEV-5 and 6. The addition and detection of MS2 RNA in each RT-qPCR reaction monitored for amplification inhibition and did not affect the performance of the assay in the detection of the HEV RNA international standard. Therefore, the RT-qPCR assay can be confidently used for the RNA detection of the seven genotypes within the species Orthohepevirus A.


Assuntos
Biologia Computacional , Hepatite E/diagnóstico , Hepatite Viral Animal/diagnóstico , Hepevirus/isolamento & purificação , Infecções por Vírus de RNA/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Hepatite E/virologia , Hepatite Viral Animal/virologia , Hepevirus/genética , Humanos , Infecções por Vírus de RNA/virologia , Sensibilidade e Especificidade
17.
Avian Pathol ; 43(4): 357-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25010035

RESUMO

Two commercial Midwestern egg-type chicken flocks experienced significant increases in mortality rates in April 2013 with clinical signs appearing in 17-week-old pullets on Farm A and in 46-week-old hens on Farm B. Average weekly mortality was 0.44% over a 4-week period on Farm A and 0.17% over an 8-week period on Farm B. On Farm A, flocks in the affected house had a 45% decrease in daily egg production from weeks 19 to 27 when compared with standard egg production curves (P < 0.01) while no decrease in egg production was noticed on Farm B. Post-mortem examination revealed changes consistent with hepatitis-splenomegaly syndrome, including hepatomegaly with serosanguineous fluid in the coelomic cavity and hepatic subcapsular haemorrhages. Microscopic lesions were characterized by multifocal necrotizing hepatitis and intrahepatic haemorrhage. No significant bacteria were recovered from liver samples, but 72 to 100% of the liver samples from affected chickens on Farm A (8/11) and Farm B (7/7) contained detectable amounts of avian hepatitis E virus (aHEV) RNA as determined by polymerase chain reaction. Sequencing and phylogenetic analysis of a 361-base-pair fragment of the helicase gene demonstrated 98.6 to 100% nucleotide identity between the aHEV genomes from Farm A and Farm B, whereas identities ranged from 74.6 to 90.5% when compared with other representative sequences. Sequences from this study clustered within aHEV genotype 2 previously recognized in the USA. In contrast to other reported aHEV outbreaks that occurred in 30-week-old to 80-week-old chickens, in the present investigation clinical aHEV was identified in 17-week-old chickens on one of the farms.


Assuntos
Galinhas , Surtos de Doenças/veterinária , Hepatite Viral Animal/virologia , Hepevirus/isolamento & purificação , Doenças das Aves Domésticas/virologia , Infecções por Vírus de RNA/virologia , Animais , Sequência de Bases , Análise por Conglomerados , Ovos , Feminino , Genoma Viral/genética , Hepatite Viral Animal/epidemiologia , Hepatite Viral Animal/mortalidade , Hepatite Viral Animal/patologia , Hepevirus/classificação , Hepevirus/genética , Fígado/patologia , Dados de Sequência Molecular , Filogenia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/mortalidade , Doenças das Aves Domésticas/patologia , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/mortalidade , Infecções por Vírus de RNA/patologia , RNA Viral/genética , Análise de Sequência de DNA/veterinária , Esplenomegalia/veterinária
18.
Avian Pathol ; 43(4): 310-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24828493

RESUMO

In a prospective longitudinal study, a broiler breeder flock and its progeny were monitored for the presence of avian hepatitis E virus (HEV) RNA and antibodies. The flock was part of a multiple-age farm where the presence of avian HEV with clinical signs (increased mortality and decreased egg production) was demonstrated in several previous production cycles. Samples were taken twice at the rearing site and several times at the production site from broiler breeders including cockerels and day-old chicks. The samples were investigated by conventional and real-time reverse transcriptase-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and histological methods. At all time points, samples from the hens were positive for avian HEV RNA. The birds did not show any clinical signs, even though histopathological lesions of non-specific aetiology in the liver and spleen could be demonstrated. A significant increase in the number of positive birds and viral load was seen in week 45, in accordance with an increase in antibody titres. In comparison, cockerels investigated in week 62 tested negative by RT-PCR and ELISA. Avian HEV RNA was also detected in day-old chicks hatched from eggs laid in week 25, indicating vertical transmission. All partial helicase and capsid sequences retrieved within this study clustered together and were identical to previous sequences obtained from the same multiple-age farm. In conclusion, avian HEV persisted on the farm over years and circulated between the rearing and the production sites without causing any clinical signs although high viral loads in the adult hens were observed.


Assuntos
Galinhas , Hepatite Viral Animal/transmissão , Hepevirus/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas/veterinária , Doenças das Aves Domésticas/transmissão , Infecções por Vírus de RNA/veterinária , Animais , Anticorpos Antivirais/imunologia , Sequência de Bases , DNA Complementar/química , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Hepatite Viral Animal/virologia , Hepevirus/genética , Hepevirus/imunologia , Fígado/virologia , Estudos Longitudinais , Dados de Sequência Molecular , Filogenia , Doenças das Aves Domésticas/virologia , Estudos Prospectivos , Infecções por Vírus de RNA/transmissão , Infecções por Vírus de RNA/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Análise de Sequência de DNA/veterinária , Baço/virologia
19.
J Viral Hepat ; 21(8): e74-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24773782

RESUMO

Hepatitis E virus (HEV) has been reported to cause acute and chronic hepatitis in those with HIV infection and among solid organ transplant recipients in Europe. Limited data indicate that HEV is endemic in the United States, but the prevalence and significance of HEV infection among those with HIV and awaiting solid organ transplantation is unknown. We evaluated anti-HEV IgM and IgG antibodies and HEV RNA in 166 HIV-infected solid organ transplant candidates enrolled in the NIH HIV-Transplant Cohort. Overall prevalence of anti-HEV IgG approached 20% in both liver and renal transplant candidates. Evidence of recent infection was present in approximately 2% of liver transplant candidates and none of the kidney transplant candidates. HEV RNA was not detected in any patient. We conclude that markers of HEV infection are frequent among candidates for transplantation, but active, ongoing viremia is not seen. Evidence of recent infection (acute on chronic) liver disease was present in liver but not kidney recipients.


Assuntos
Infecções por HIV/complicações , Hepatite E/epidemiologia , Hepevirus/isolamento & purificação , Adulto , Feminino , Anticorpos Anti-Hepatite/sangue , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , RNA Viral/sangue , Estados Unidos/epidemiologia
20.
Eur J Clin Microbiol Infect Dis ; 33(6): 1037-43, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24445407

RESUMO

PURPOSE: In developed countries, hepatitis E virus (HEV) is considered an emerging pathogen, but prevalence seems highly variable according to previous European studies. As HEV can lead to chronic infections in immunosuppressed patients, it is thus essential to evaluate the prevalence and incidence of this infection. METHODS: We determined retrospectively, in a cohort of 206 pediatric and adult liver transplant recipients from the Rhône-Alpes region in France, pre-transplant anti-HEV-IgG prevalence and incidence of HEV infections during post-transplant follow-up (HEV IgG and IgM ± HEV-RNA). RESULTS: Transplantations were carried out between 2005 and 2012 and mean post-transplant follow-up was 32.8 months. Global pre-transplant prevalence of anti-HEV IgG was 29%, increasing regularly with age from 7% for children under 15 to 49% for patients older than 60. From the 142 seronegative patients before transplant, 11 seroconversions (7.7%) were observed during follow-up (incidence of 2.83 cases per 100 person-years). HEV RNA-tested at transaminases peak or randomly-was detected in only one case of seroconversion. For at least 2 HEV-seropositive patients, who had negative RNAemia before transplantation, viral RNA was detected chronically during follow-up, suggesting reinfection with HEV. CONCLUSION: Acute infections were largely more frequent than chronic infections and were asymptomatic or misdiagnosed, suggesting that liver transplant patients may not be particularly prone to developing severe HEV hepatitis. In addition, the presence of IgG anti-HEV may not protect against re-infection. Serological testing, therefore, appears to be of limited interest for the diagnosis of HEV infections in liver transplant recipients.


Assuntos
Hepatite E/epidemiologia , Hepevirus/isolamento & purificação , Transplante de Fígado , Transplantados , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , França/epidemiologia , Anticorpos Anti-Hepatite/sangue , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Soroepidemiológicos , Adulto Jovem
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