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1.
Food Microbiol ; 109: 104114, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36309428

RESUMO

Hepatitis E virus (HEV) is the causative agent of hepatitis E. Some of the rise in hepatitis E infection in China may be linked to undercooked pork. In this study, we established a reverse transcription droplet digital PCR (RT-ddPCR) method to detect HEV in raw pork livers. The detection limit of the assay for HEV RNA was as low as 1.81 copies/µL. The suggested approach was validated on 14 samples, demonstrating greater sensitivity, specificity, and anti-interference performance features than RT-qPCR. Furthermore, we amplified the partial ORF2 gene by nested RT-PCR and sequenced for the HEV RNA positive samples. The prevalence of HEV in all collected samples was 2.24% (14/626), and the viral load was between 8.0 copies/µL and 8975 copies/µL. Specifically, the virus was detected in 10.62% (12/113) of the samples collected from the bio-safety disposal centers for dead livestock and poultry, in 0.67% (2/300) of the samples collected from the slaughterhouses, and none of the samples collected from the retail markets was HEV RNA positive. The subsequent phylogenetic analysis revealed that all HEV isolates belonged to the subtype 4d, which is one of the most common subtypes in northern China.


Assuntos
Vírus da Hepatite E , Hepatite E , Carne de Porco , Carne Vermelha , Doenças dos Suínos , Animais , Suínos , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carne Vermelha/análise , Filogenia , RNA Viral/genética , RNA Viral/análise , Doenças dos Suínos/epidemiologia , Genótipo
2.
Emerg Infect Dis ; 28(12): 2543-2547, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36417998

RESUMO

Epidemiologic surveillance of hepatitis E virus in over 300 free-ranging and captive cetaceans in waters off Spain revealed extensive exposure to this pathogen. We suggest the persistent and widespread presence of hepatitis E in the marine environment off the coast of Spain may be driven by terrestrial sources of contamination.


Assuntos
Vírus da Hepatite E , Hepatite E , Humanos , Vírus da Hepatite E/genética , Hepatite E/epidemiologia , Hepatite E/veterinária , Espanha/epidemiologia
3.
J Gen Virol ; 103(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36354744

RESUMO

Ferrets are widely used for experimental modelling of viral infections. However, background disease in ferrets could potentially confound intended experimental interpretation. Here we report the detection of a subclinical infection of ferret hepatitis E virus (FRHEV) within a colony sub-group of female laboratory ferrets that had been enrolled on an experimental viral infection study (non-hepatitis). Lymphoplasmacytic cuffing of periportal spaces was identified on histopathology but was negative for the RNA and antigens of the administered virus. Follow-up viral metagenomic analysis conducted on liver specimens revealed sequences attributed to FRHEV and these were confirmed by reverse-transcriptase polymerase chain reaction. Further genomic analysis revealed contiguous sequences spanning 79-95 % of the FRHEV genome and that the sequences were closely related to those reported previously in Europe. Using in situ hybridization by RNAScope, we confirmed the presence of HEV-specific RNA in hepatocytes. The HEV open reading frame 2 (ORF2) protein was also detected by immunohistochemistry in the hepatocytes and the biliary canaliculi. In conclusion, the results of our study provide evidence of background infection with FRHEV in laboratory ferrets. As this infection can be subclinical, we recommend routine monitoring of ferret populations using virological and liver function tests to avoid incorrect causal attribution of any liver disease detected in in vivo studies.


Assuntos
Vírus da Hepatite E , Hepatite E , Animais , Feminino , Vírus da Hepatite E/genética , Furões , RNA Viral/genética , RNA Viral/análise , Hepatite E/veterinária , Reino Unido
4.
Biomolecules ; 12(11)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36358893

RESUMO

The molecular mechanism of hepatitis E virus (HEV) pathology is still unclear. The micro RNAs (miRNAs), of host or viral origin, interfere with virus replication and host environment in order to create an appropriate condition for the production of mature HEV progeny. Understanding the biogenesis and the interference of miRNAs with HEV will help to revile the mechanism of viral pathogenesis.


Assuntos
Vírus da Hepatite E , Hepatite E , MicroRNAs , Humanos , Vírus da Hepatite E/genética , MicroRNAs/genética , Hepatite E/genética , Hepatite E/patologia , Replicação Viral/genética
5.
Viruses ; 14(11)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36423134

RESUMO

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide. In many low-income countries it causes large outbreaks and disproportionally affects pregnant women and their offspring. Surveillance studies to find effective preventive interventions are needed but are hampered by the lack of funding and infrastructure. Dried blood spots (DBS) offer an easier and more robust way to collect, transport, and store blood samples compared to plasma/serum samples, and could ease some of the barriers for such studies. In this study we optimize an HEV IgG ELISA for DBS samples and validate it on 300 paired DBS and plasma samples collected in rural areas of Bangladesh from participants in a HEV vaccine study. We demonstrate that HEV IgG in blood stored as DBS is stable for two months at up to 40 °C, and for five freeze-thaw cycles. The specificity was 97% and the overall sensitivity of the DBS assay was 81%. The sensitivity was higher in samples from vaccinated participants (100%) compared to previously infected participants (59%), reflecting a positive correlation between IgG titer and sensitivity. We found a strong correlation between DBS and plasma samples with an r2 of 0.90, but with a higher degree of difference between individual paired samples. Our study shows that DBS offers a stable alternative to plasma/serum for HEV IgG measurements and can facilitate serological studies, particularly in resource limited areas.


Assuntos
Vírus da Hepatite E , Feminino , Humanos , Gravidez , Estudos de Viabilidade , Anticorpos Anti-Hepatite , Testes Hematológicos , Imunoglobulina G
6.
J Clin Virol ; 157: 105325, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36395548

RESUMO

BACKGROUND: To harmonize assays for detection of HEV RNA, a World Health Organization International Standard (WHO IS) was established. The WHO IS represents the highest order standard for HEV RNA but is limited in quantity. Secondary standards are needed to limit the use of WHO IS and minimize the need to replace it. OBJECTIVE: Establish secondary standards for HEV NAAT assays and to calibrate these against the WHO IS. METHODS: Stocks of genotype 3 HEV were prepared using both cell lysates and cell culture supernatants to produce non-enveloped and quasi-enveloped virus stocks, respectively. Both stocks were heat-inactivated, diluted in negative human plasma, and lyophilized to produce two candidate secondary standards: HEV-RR (non-enveloped virus) and HEV-RR.1 (quasi-enveloped virus). Both candidate standards were characterized and calibrated against the WHO IS for HEV RNA in an international collaborative study. RESULTS: The collaborative study returned a total of 15 data sets, with different RNA extraction and amplification methods. The estimated mean values relative to the WHO IS (250,000 IU/ml) are 229,000 IU/ml and 355,000 IU/ml for HEV-RR and HEV-RR.1, respectively. CONCLUSION: We have established two secondary standards for HEV RNA calibrated against the WHO IS. These standards are non-infectious and stable under different storage temperatures.


Assuntos
Vírus da Hepatite E , Humanos , Vírus da Hepatite E/genética , RNA Viral/genética , Cooperação Internacional , Padrões de Referência , Tecnologia
7.
Viruses ; 14(11)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36366538

RESUMO

Hepatitis E virus (HEV) is increasingly recognized as the leading cause of acute hepatitis. Although HEV infections are mostly self-limiting, a chronic course can develop especially in those with immunocompromised state. Ribavirin is currently used to treat such patients. According to various reports on chronic HEV infections, a sustained virological response (SVR) was achieved in approximately 80% of patients receiving ribavirin monotherapy. To increase the SVR rate, drug combination might be a viable strategy, which we attempted in the current study. Ritonavir was identified in our previous drug screening while searching for candidate novel anti-HEV drugs. It demonstrated potent inhibition of HEV growth in cultured cells. In the present study, ritonavir blocked HEV internalization as shown through time-of-addition and immunofluorescence assays. Its combination with ribavirin significantly increased the efficiency of inhibiting HEV growth compared to that shown by ribavirin monotherapy, even in PLC/PRF/5 cells with robust HEV production, and resulted in viral clearance. Similar efficiency was seen for HEV genotypes 3 and 4, the main causes of chronic infection. The present findings provide insight concerning the advantage of combination therapy using drugs blocking different steps in the HEV life cycle (internalization and RNA replication) as a potential novel treatment strategy for chronic hepatitis E.


Assuntos
Vírus da Hepatite E , Hepatite E , Humanos , Vírus da Hepatite E/genética , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Ritonavir/farmacologia , Ritonavir/uso terapêutico , Internalização do Vírus , Antivirais/farmacologia , Antivirais/uso terapêutico
8.
J Microbiol Biotechnol ; 32(10): 1335-1343, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36224764

RESUMO

COVID-19 is an emerging disease that poses a severe threat to global public health. As such, there is an urgent demand for vaccines against SARS-CoV-2, the virus that causes COVID-19. Here, we describe a virus-like nanoparticle candidate vaccine against SARS-CoV-2 produced by an E. coli expression system. The fusion protein of a truncated ORF2-encoded protein of aa 439~608 (p170) from hepatitis E virus CCJD-517 and the receptor-binding domain of the spike protein from SARS-CoV-2 were expressed, purified and characterized. The antigenicity and immunogenicity of p170-RBD were evaluated in vitro and in Kunming mice. Our investigation revealed that p170-RBD self-assembled into approximately 24 nm virus-like particles, which could bind to serum from vaccinated people (p < 0.001) and receptors on cells. Immunization with p170-RBD induced the titer of IgG antibody vaccine increased from 14 days post-immunization and was significantly enhanced after a booster immunization at 28 dpi, ultimately reaching a peak level on 42 dpi with a titer of 4.97 log10. Pseudovirus neutralization tests showed that the candidate vaccine induced a strong neutralizing antibody response in mice. In this research, we demonstrated that p170-RBD possesses strong antigenicity and immunogenicity and could be a potential candidate for use in future SARS-CoV-2 vaccine development.


Assuntos
COVID-19 , Vírus da Hepatite E , Vacinas Virais , Animais , Humanos , Camundongos , Anticorpos Neutralizantes , Anticorpos Antivirais , Proteínas do Capsídeo/genética , COVID-19/prevenção & controle , Vacinas contra COVID-19/genética , Escherichia coli , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Vacinas Virais/genética
9.
Rev Med Virol ; 32(6): e2401, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36209386

RESUMO

Hepatitis E virus (HEV) infection occurs worldwide. The HEV genome includes three to four open reading frames (ORF1-4). ORF1 proteins are essential for viral replication, while the ORF3 protein is an ion channel involved in the exit of HEV from the infected cells. ORF2 proteins form the viral capsid required for HEV invasion and assembly. They also suppress interferon production and inhibit antibody-mediated neutralisation of HEV, allowing the virus to hijack the host immune response. ORF2 is the only detectable viral protein in the human liver during HEV infection and it is secreted in the plasma, stool, and urine of HEV-infected patients, making it a reliable diagnostic marker. The plasma HEV ORF2 antigen level can predict the outcome of HEV infections. Hence, monitoring HEV ORF2 antigen levels may be useful in assessing the efficacy of anti-HEV therapy. The ORF2 antigen is immunogenic and includes epitopes that can induce neutralising antibodies; therefore, it is a potential HEV vaccine candidate. In this review, we highlighted the different forms of HEV ORF2 protein and their roles in HEV pathogenesis, diagnosis, monitoring the therapeutic efficacy, and vaccine development.


Assuntos
Vírus da Hepatite E , Hepatite E , Humanos , Vírus da Hepatite E/genética , Fases de Leitura Aberta , Hepatite E/diagnóstico , Epitopos
10.
Virus Genes ; 58(6): 589-593, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36183048

RESUMO

Hepatitis E virus (HEV) infection has a global distribution with diverse hosts, including mammals and avians. In this study, an avian Hepatitis E virus (aHEV) strain with a high mortality rate of about 30%, designated as SDXT20, was obtained from the liver of 30-week-old Hubbard chickens with severe hepatosplenomegaly in 2020 in Eastern China and HEV was proved to be the only pathogen by next-generation sequencing. Its complete genome, which encodes three open reading frames (ORFs), is 6649 nt in length. ORF1-3 encodes three proteins with lengths of 1532 aa, 606 aa, and 82 aa, respectively, and ORF2 and ORF3 overlap with each other. BLAST-based similarity analysis of the complete viral genome demonstrated that SDXT20 had merely 80.5-92.2% similarity with avian Avihepevirus magniiecur strains and 50.4%-54.8% lower similarity with Paslahepevirus balayani, Rocahepevirus ratti, and Chirohepevirus eptesici species. Further genetic evolution analysis of the complete genome and ORF2 revealed that the isolate was genetically distinct from known aHEVs, and it belonged to a novel genetically distinct aHEV. This study provides data for further analysis of the multi-host and cross-host genetic evolution of HEVs.


Assuntos
Vírus da Hepatite E , Hepatite E , Hepevirus , Animais , Hepevirus/genética , Galinhas , Vírus da Hepatite E/genética , Hepatite E/veterinária , Genoma Viral/genética , Fases de Leitura Aberta/genética , China , Mamíferos
11.
Sci Rep ; 12(1): 17878, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284151

RESUMO

The Rapid proliferation of traditional gold mining sites in the Kedougou region has led to massive migration of people from neighbouring West African countries and the establishment of several small villages where poor hygiene and sanitation conditions exist. In this context, a Hepatitis E virus outbreak was reported in Kedougou in 2014 with several cases among the traditional mining workers. Herein, we described epidemiological and laboratory data collected during the outbreak's investigation from February 2012 to November 2014. Any suspected, contact or probable case was investigated, clinical and epidemiological data were collected. In our study, sera were collected and tested for viral RNA and anti-Hepatitis E virus (HEV) IgM. Archived serum samples from Kedougou were retrospectively screened by real-time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). A total of 65 water samples collected from ponds and wells surrounding gold panners' sites and habitats and 75 tissues samples from rats captured in the environment of traditional gold mining sites were also tested. A total of 1617 sera were collected from 698 suspected cases, 862 contacts and 57 persons with missing information. The median age was 20 (1-88 years-old) and the sex ratio was 1.72. An overall rate of 64.62% (1045/1617) of these patients tested positive for HEV with a high case fatality rate in pregnant women. All water samples and animal tissues tested negative for HEV. Our data help not only determining of the beginning of the HEV outbreak to March 2012, but also identifying risk factors associated to its emergence. However, there is a need to implement routine diagnosis, surveillance and training of health personnel in order to reduce mortality especially among pregnant women. In addition, further studies are needed to identify the virus reservoir and environmental risk factors for HEV in the Kedougou region.


Assuntos
Vírus da Hepatite E , Hepatite E , Feminino , Humanos , Gravidez , Ratos , Animais , RNA Viral/genética , Estudos Retrospectivos , Senegal , Vírus da Hepatite E/genética , Anticorpos Anti-Hepatite , Imunoglobulina M , Surtos de Doenças , Ensaio de Imunoadsorção Enzimática , Ouro , Água
12.
World J Gastroenterol ; 28(37): 5494-5505, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36312833

RESUMO

BACKGROUND: Hepatitis E virus (HEV) is an emerging virus of global health concern. The seroprevalence rates differ greatly according to geographic region and population group. AIM: To analyze the seroprevalence of HEV in exposed (animal-related professions) and nonexposed populations, as well as solid organ and hematopoietic stem cell transplant patients. METHODS: Forestry workers (n = 93), hunters (n = 74), and veterinarians (n = 151) represented the exposed population. The general population (n = 126) and pregnant women (n = 118) constituted the control group. Transplant patients included liver transplant recipients (LTRs) (n = 83), kidney transplant recipients (KTRs) (n = 43), and hematopoietic stem cell transplant recipients (HSCRs) (n = 39). HEV immunoglobulin G antibodies were detected using the enzyme-linked immunosorbent assay and confirmed by the immunoblot test. RESULTS: The HEV seroprevalence significantly differed between groups: Veterinarians 15.2%, hunters 14.9%, forestry workers 6.5%, general population 7.1%, and pregnant women 1.7%. In transplant patients, the seropositivity was highest in LTRs (19.3%), while in KTRs and HSCRs, the seroprevalence was similar to the general population (6.9% and 5.1%, respectively). A significant increase in seropositivity with age was observed from 2.9% in individuals less than 30 years to 23.5% in those older than 60 years. Sociodemographic characteristics (sex, educational level, area of residence, and number of household members), eating habits (game meat, offal, and pork products consumption), and environmental and housing conditions (drinking water supply, type of water drainage/sewer, waste disposal, domestic animals) were not associated with HEV seropositivity. However, individuals who reported a pet ownership were more often seropositive compared to those who did not have pet animals (12.5% vs 7.0%). CONCLUSION: The results of this study showed that individuals in professional contact with animals and LTRs are at higher risk for HEV infection. In addition, age is a significant risk factor for HEV seropositivity.


Assuntos
Vírus da Hepatite E , Hepatite E , Gravidez , Animais , Humanos , Feminino , Estudos Soroepidemiológicos , Croácia/epidemiologia , Imunoglobulina G , Anticorpos Anti-Hepatite , Fatores de Risco
13.
Viruses ; 14(10)2022 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-36298671

RESUMO

Hepatitis E virus (HEV) is the most prevalent hepatitis virus worldwide. Genotypes 3 (HEV3) and 4 (HEV4) as well as rat HEV can lead to chronic hepatitis E and cirrhosis in immunosuppressed patients. Within the last decade, several options for treating chronic hepatitis have been developed and have achieved a sustained virological response. However, there are still unmet needs such as optimizing immunosuppression to allow HEV clearance with or without ribavirin, as well as alternative therapies to ribavirin that are discussed in this paper.


Assuntos
Vírus da Hepatite E , Hepatite E , Ratos , Animais , Vírus da Hepatite E/genética , Hepatite E/tratamento farmacológico , Ribavirina/uso terapêutico , Hospedeiro Imunocomprometido , Hepatite Crônica/tratamento farmacológico
14.
Viruses ; 14(10)2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36298677

RESUMO

Hepatitis E virus (HEV) is an important public health burden worldwide, causing approximately 20 million infections and 70,000 deaths annually. The viral capsid protein is encoded by open reading frame 2 (ORF2) of the HEV genome. Most ORF2 protein present in body fluids is the glycosylated secreted form of the protein (ORF2S). A recent study suggested that ORF2S is not necessary for the HEV life cycle. A previously reported efficient HEV cell culture system can be used to understand the origin and life cycle of ORF2S but is not sufficient for functional research. A more rapid and productive method for yielding ORF2S could help to study its antigenicity and immunogenicity. In this study, the ORF2S (tPA) expression construct was designed as a candidate tool. A set of representative anti-HEV monoclonal antibodies was further used to map the functional antigenic sites in the candidates. ORF2S (tPA) was used to study antigenicity and immunogenicity. Indirect ELISA revealed that ORF2S (tPA) was not antigenically identical to HEV 239 antigen (p239). The ORF2S-specific antibodies were successfully induced in one-dose-vaccinated BALB/c mice. The ORF2S-specific antibody response was detected in plasma from HEV-infected patients. Recombinant ORF2S (tPA) can act as a decoy to against B cells. Altogether, our study presents a design strategy for ORF2S expression and indicates that ORF2S (tPA) can be used for functional and structural studies of the HEV life cycle.


Assuntos
Vírus da Hepatite E , Hepatite E , Camundongos , Animais , Vírus da Hepatite E/genética , Proteínas do Capsídeo/genética , Fases de Leitura Aberta , Camundongos Endogâmicos BALB C , Anticorpos Monoclonais/genética
15.
Front Immunol ; 13: 954697, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275730

RESUMO

Hepatitis E virus (HEV) is one of the most important public health issues around the world, and chronic HEV infection has been reported in immunosuppressed individuals. This study reported a male case, with very severe aplastic anemia (AA), who developed chronic hepatitis E after hematopoietic stem cell transplantation (HSCT). Abnormal alanine aminotransferase (ALT) appeared after HSCT and persisted for twenty-nine months. The case was seropositive for anti-HEV IgG and IgM after HSCT. Twenty-two months after HSCT, HEV RNA and antigen (Ag) testing were positive and persisted for five and seven months, respectively. Positive stains of HEV Ag were present in a liver biopsy sample. HEV Ag was present in bone marrow. The individual rapidly developed liver cirrhosis and was rescued by a regimen of oral ribavirin. These factors suggested there is a risk of HEV infection in HSCT recipients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Vírus da Hepatite E , Hepatite E , Masculino , Humanos , Vírus da Hepatite E/genética , Hepatite E/diagnóstico , Hepatite E/tratamento farmacológico , Ribavirina/uso terapêutico , Alanina Transaminase , Infecção Persistente , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Imunoglobulina G/genética , Imunoglobulina M/genética , RNA , Genótipo
16.
Front Cell Infect Microbiol ; 12: 958990, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36132988

RESUMO

Hepatitis E virus (HEV) is a zoonotic pathogen that causes global hepatitis E. Outbreaks of hepatitis E are directly linked to the consumption of pork liver products. Herein reverse transcription recombinase polymerase amplification assays targeting the ORF2 gene were developed for the rapid detection of HEV by integrating the fluorescence detection platform (qRT-RPA) and the visible lateral flow biosensor by naked eyes (LFB RT-RPA). The qRT-RPA assay effectively detected HEV RNA with a limit of detection (LOD) of 154 copies/µl (95%CI: 126-333 copies/µl) in Genie III at 41°C for 20 min. Besides this, the LFB RT-RPA detected the HEV RNA with a LOD of 24 copies/µl (95%CI: 20-57 copies/µl) in an incubator block at 41°C for 20 min. The developed RT-RPA assays also showed good specificity for HEV, with no cross-reactions with any of the other important swine pathogens examined in this work. The performance of the developed RT-RPA assays was validated on 14 HEV RNA-positive and 66 HEV RNA-negative raw pork liver samples identified by a previously described qRT-PCR. Consequently, 11 and 12 samples were HEV RNA-positive as detected by the qRT-RPA and the LFB RT-RPA, respectively. Compared to qRT-PCR, the qRT-RPA and LFB RT- RPA assays revealed a coincidence rate of 96.3 and 97.5% as well as a Kappa value of 0.858 and 0.908, respectively. These results ascertain that the developed RT-RPA assays are effective diagnostic tools for the point-of-care detection of HEV in resource-limited settings.


Assuntos
Vírus da Hepatite E , Hepatite E , Carne de Porco , Carne Vermelha , Animais , Hepatite E/diagnóstico , Hepatite E/veterinária , Vírus da Hepatite E/genética , RNA , Reação em Cadeia da Polimerase em Tempo Real , Recombinases , Sensibilidade e Especificidade , Suínos
17.
Microbiol Spectr ; 10(5): e0214622, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36125314

RESUMO

This study aimed to calibrate hepatitis E virus (HEV) serological assays. We optimized the previously developed in-house HEV antibody enzyme-linked immunosorbent assay (ELISA) by setting the cutoff with an in-house serological performance panel consisting of broad HEV antibody titers and subtracting nonspecific background values for anti-HEV IgM, IgA, and IgG. We also compared the assay's performance with that of commercial serological assay kits (four kits for IgM, one for IgA, and two for IgG). Although all serological assays readily detected HEV antibodies at high titers in the symptomatic hepatitis E population, considerable variations between assays were observed in the asymptomatic population. The in-house ELISA showed a higher sensitivity for HEV IgM, IgA, and IgG than the commercial kits and detected the seroconversion of HEV IgM and IgG earlier when testing a commercially available HEV seroconversion panel. The low sensitivity of the commercial kits was due to the high setting of the original cutoff, which was demonstrated by receiver operating characteristic analysis. However, the corrected cutoff value reduced assay specificity. Background subtraction is essential to achieve high specificity because the in-house ELISA without background subtraction reduced its specificity. These results indicate that asymptomatic specimens and background subtraction contribute to the optimization of HEV serological assays. IMPORTANCE Accurate diagnosis of hepatitis E virus (HEV) infection is essential for public health surveillance and for preventing HEV-contaminated blood transfusion. Anti-HEV IgM or IgA is used as a reliable marker of recent HEV infection. However, considerable variability in the sensitivity and specificity of HEV antibody detection is observed among several commercially available assay kits. In addition, none of the HEV antibody detection methods have been approved by the U.S. Food and Drug Administration (FDA). Here, we show that the in-house enzyme-linked immunosorbent assay (ELISA) could detect HEV IgM and IgA more sensitively than commercial kits in the asymptomatic population. We also suggest that the assay performance of commercial kits might be improved by optimizing the cutoff and reducing nonspecific background noise. A sensitive serological (IgM or IgA) assay in addition to HEV RNA testing will contribute to accurate diagnosis of acute HEV infection because HEV RNA-positive duration is relatively short.


Assuntos
Vírus da Hepatite E , Hepatite E , Humanos , Vírus da Hepatite E/genética , Japão/epidemiologia , Imunoglobulina G , Anticorpos Anti-Hepatite , Hepatite E/diagnóstico , Hepatite E/epidemiologia , Imunoglobulina M , RNA , Imunoglobulina A
18.
Transfusion ; 62(11): 2200-2204, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36125237

RESUMO

BACKGROUND AND OBJECTIVES: Photodynamic treatment with methylene blue (MB) and visible light is a well-established pathogen inactivation system for human plasma. This technique is routinely used in different countries. MB/light treatment was shown to inactivate several transfusion-transmittable viruses, but its efficiency for the inactivation of the quasi-enveloped hepatitis E virus (HEV) has not yet been investigated. MATERIALS AND METHODS: Plasma units were spiked with cell culture-derived HEV and treated with the THERAFLEX MB-Plasma system using various light doses (30, 60, 90, and 120 J/cm2 ). HEV titers in pre- and post-treatment samples were determined by virus titration and a large-volume plating assay to improve the detection limit of the virus assay. RESULTS: THERAFLEX MB-Plasma efficiently inactivated HEV in human plasma. Even the lowest light dose of 30 J/cm2 inactivated HEV down to the limit of detection, with a mean log reduction factor of greater than 2.4 for the total process. CONCLUSION: Our study demonstrates that the THERAFLEX MB-Plasma system effectively inactivates HEV in human plasma.


Assuntos
Vírus da Hepatite E , Azul de Metileno , Humanos , Azul de Metileno/farmacologia , Inativação de Vírus , Raios Ultravioleta , Luz
19.
Braz J Microbiol ; 53(4): 1995-2001, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36100808

RESUMO

Oral transmission is the main route of hepatitis E virus (HEV) infection; however, genotypes 3 and 4 may also be transmitted by blood transfusion. Individuals who need blood products are often immunosuppressed, which increase the risk of severe disease and death by HEV. Despite this, blood banks in Brazil do not screen for HEV and epidemiological studies in this population are rare; this is an important issue as HEV-3 is frequently identified in the country. Herein, we analyzed the seroprevalence and risk factors for HEV seropositivity in donor candidates/blood donors from Northeast Brazil. Nine hundred and ninety-six donor candidates/blood donors from Foundation of Hematology and Hemotherapy of Pernambuco (HEMOPE) were interviewed regarding socioeconomic, sociodemographic, and behavioral data and analyzed for anti-HEV IgG. Anti-HEV IgG was detected using the HEV IgG (EUROIMMUN) kit. Associations between seropositivity and potential risk factors were analyzed by the χ2 test and Fisher's exact test. Seroprevalence was 0.9% (9/996), 77.77% (7/9) and 22.22% (2/9) in blood donors and donor candidates, respectively. HEV seropositivity was associated with male (OR: 11.65; CI: 0.6755-200.9; p = 0.0163), income higher than BRL 20,000/month (p = 0.0002), and lake bathing (OR: 4.553; CI: 1.391-15.25; p = 0.0258). Importantly, about 43% (3/7) of anti-HEV positive donors made their first donation more than 20 years ago, which must be taken as a warning sign, given the possibility that these individuals may have been infected after registration as donors. Finally, the report of HEV seropositivity, especially in regular blood donors, as well as the identification of potential risk factors, reinforces the need for viral screening in Brazilian blood banks.


Assuntos
Vírus da Hepatite E , Hepatite E , Masculino , Humanos , Vírus da Hepatite E/genética , Estudos Soroepidemiológicos , Doadores de Sangue , Hepatite E/epidemiologia , Brasil/epidemiologia , Anticorpos Anti-Hepatite , Imunoglobulina G , Fatores de Risco , RNA Viral
20.
J Food Prot ; 85(12): 1690-1695, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048964

RESUMO

ABSTRACT: Infection with hepatitis E virus genotype 3 (HEV-3) is an emerging cause of illness in developed countries. In North America and Europe, HEV-3 has been increasingly detected in swine, and exposure to pigs and pork products is considered the primary source of infection. We have previously demonstrated the prevalence of the HEV-3 genome in commercial pork products in Canada. In this study, we investigated the application of citric acid and acetic acid to inactivate HEV-3 on food and on food contact surfaces. For this purpose, plastic, stainless steel, and pork pâté surfaces were inoculated with HEV-3 and were treated with acetic acid or citric acid at 1, 3, or 5%. The infectivity of posttreatment viral particles was determined by cell culture. A greater than 2-log reduction in viral infectivity was observed on plastic and stainless steel treated with the organic acids, but the treatment was less effective on HEV infectivity on pork pâté (average reductions of 0.47 log citric acid and 0.63 log acetic acid). Therefore, we conclude that citric acid and acetic acid have potential application to control HEV-3 on food contact surfaces but are not suitable for food.


Assuntos
Vírus da Hepatite E , Suínos , Animais , Aço Inoxidável , Plásticos , Ácido Acético , Ácido Cítrico/farmacologia
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