1
|
Abstract
Recent discoveries of contemporary genotypes of hepatitis B virus and parvovirus B19 in ancient human remains demonstrate that little genetic change has occurred in these viruses over 4,500-6,000 years. Endogenous viral elements in host genomes provide separate evidence that viruses similar to many major contemporary groups circulated 100 million years ago or earlier. In this Opinion article, we argue that the extraordinary conservation of virus genome sequences is best explained by a niche-filling model in which fitness optimization is rapidly achieved in their specific hosts. Whereas short-term substitution rates reflect the accumulation of tolerated sequence changes within adapted genomes, longer-term rates increasingly resemble those of their hosts as the evolving niche moulds and effectively imprisons the virus in co-adapted virus-host relationships. Contrastingly, viruses that jump hosts undergo strong and stringent adaptive selection as they maximize their fit to their new niche. This adaptive capability may paradoxically create evolutionary stasis in long-term host relationships. While viruses can evolve and adapt rapidly, their hosts may ultimately shape their longer-term evolution.
Collapse
|
2
|
Comprehensive analysis of genetic and evolutionary features of the hepatitis E virus. BMC Genomics 2019; 20:790. [PMID: 31664890 PMCID: PMC6820953 DOI: 10.1186/s12864-019-6100-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 09/12/2019] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The hepatitis E virus (HEV) is the causative pathogen of hepatitis E, a global public health concern. HEV comprises 8 genotypes with a wide host range and geographic distribution. This study aims to determine the genetic factors influencing the molecular adaptive changes of HEV open reading frames (ORFs) and estimate the HEV origin and evolutionary history. RESULTS Sequences of HEV strains isolated between 1982 and 2017 were retrieved and multiple analyses were performed to determine overall codon usage patterns, effects of natural selection and/or mutation pressure and host influence on the evolution of HEV ORFs. Besides, Bayesian Coalescent Markov Chain Monte Carlo (MCMC) Analysis was performed to estimate the spatial-temporal evolution of HEV. The results indicated an A/C nucleotide bias and ORF-dependent codon usage bias affected mainly by natural selection. The adaptation of HEV ORFs to their hosts was also ORF-dependent, with ORF1 and ORF2 sharing an almost similar adaptation profile to the different hosts. The discriminant analysis based on the adaptation index suggested that ORF1 and ORF3 could play a pivotal role in viral host tropism. CONCLUSION In this study, we estimate that the common ancestor of the modern HEV strains emerged ~ 6000 years ago, in the period following the domestication of pigs. Then, natural selection played the major role in the evolution of the codon usage of HEV ORFs. The significant adaptation of ORF1 of genotype 1 to humans, makes ORF1 an evolutionary indicator of HEV host speciation, and could explain the epidemic character of genotype 1 strains in humans.
Collapse
|
3
|
Shirazi R, Pozzi P, Wax M, Bar-Or I, Asulin E, Lustig Y, Mendelson E, Ben-Ari Z, Schwartz E, Mor O. Hepatitis E in pigs in Israel: seroprevalence, molecular characterisation and potential impact on humans. ACTA ACUST UNITED AC 2019; 23. [PMID: 30621824 PMCID: PMC6290533 DOI: 10.2807/1560-7917.es.2018.23.49.1800067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
IntroductionThe zoonotic hepatitis E virus (HEV) genotype 3 (HEV-G3) has become a common cause of acute and chronic hepatitis among humans worldwide. In Israel, while HEV-3 sequences have previously been detected in sewage, only the non-zoonotic HEV-G1 genotype has been found in samples from human patients.AimIn this pilot study, we aimed to assess the status of HEV in a sample of the swine population and among swine farm workers in Israel.MethodsPig blood (n = 141) and faecal samples (n = 39), pig farm sewage samples (n = 8) and blood from farm workers (n = 24) were collected between February 2016 and October 2017. Anti-HEV IgG was detected using the Wantai assay. HEV RNA was analysed with the RealStar HEV kit. HEV open reading frame 1 fragments amplified from representative HEV RNA-positive samples were used for phylogenetic analysis.ResultsOverall prevalence of HEV antibodies in pigs was 75.9% (107/141). HEV RNA was detected in plasma (2.1%, 3/141), faecal (22.8%, 18/79) and pig sewage (4/8) samples. Pig and sewage-derived viral sequences clustered with previously identified human sewage HEV-G3 sequences. Most pig farms workers (23 of 24) were HEV-seropositive; none was viraemic or reported previous clinical signs.ConclusionsThis study showed that domestic pigs in Israel are infected with HEV-G3. The high HEV seropositivity of the farm workers together with the previous identification of this virus in human sewage suggests circulation to humans. The clinical impact of these findings on public health should be further explored.
Collapse
Affiliation(s)
- Rachel Shirazi
- These authors contributed equally to this article.,Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| | - Paolo Pozzi
- Israel Ministry of Agriculture and Rural Development Plant Protection and Inspection Services, Veterinary Services Beit Dagan, Beit Dagan, Israel.,These authors contributed equally to this article
| | - Marina Wax
- Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| | - Itay Bar-Or
- Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| | - Efrat Asulin
- Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| | - Yaniv Lustig
- Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| | - Ella Mendelson
- School of Public Health, Sackler Faculty of Medicine Tel Aviv University, Tel Aviv, Israel.,Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| | - Ziv Ben-Ari
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Liver Diseases Center, Chaim Sheba Medical Center, Tel Hashomer, Ramat-Gan, Israel
| | - Eli Schwartz
- Center for Geographic Medicine and Tropical Diseases, Chaim Sheba Medical Center, Tel Hashomer, Ramat-Gan, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Orna Mor
- School of Public Health, Sackler Faculty of Medicine Tel Aviv University, Tel Aviv, Israel.,Central Virology Laboratory, Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel
| |
Collapse
|
4
|
Bansal M, Kaur S, Deka D, Singh R, Gill JPS. Seroepidemiology and molecular characterization of hepatitis E virus infection in swine and occupationally exposed workers in Punjab, India. Zoonoses Public Health 2017; 64:662-672. [PMID: 28449278 DOI: 10.1111/zph.12363] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Indexed: 12/19/2022]
Abstract
Hepatitis E virus (HEV) has two discrete epidemiological patterns: waterborne epidemics in developing countries only, caused by HEV genotype I, and sporadic zoonotic outbreaks in developing and developed countries caused by genotypes III and IV. This study was designed to investigate seroprevalence, molecular detection and the characterization of HEV by nested RT-PCR in swine as well as the occupational risk to exposed human population in Punjab state of north-western India. The occupational risk-exposed group comprised of swine farmers (organized - mixed feed feeders and unorganized - swill feeders), slaughterhouse workers, sewage workers and veterinary internes. During the study period, blood and faecal samples were collected from 320 swine and 360 humans with both high and low occupational exposure risks. The overall seroprevalence of swine HEV was 65.00%, with a significantly higher seropositivity in growing pigs (2-8 months of age). The prevalence of HEV RNA in swine faecal samples by nRT-PCR was 8.75% with a significantly higher detection in swill-fed pigs. With humans in the high occupational exposure risk population, significantly higher anti-HEV IgG seropositivity was observed (60.48%) as compared to control population (10.71%). Strong evidence of association between human anti-HEV IgG seropositivity and certain occupational exposure risk groups was observed (p < 0.05). This indicates that unorganized swine farmers, slaughterhouse workers and sewage workers have higher odds of HEV infection in this study region. Percentage of nucleotide similarity between swine and human HEV isolates was less than that found in countries with zoonotic HEV outbreaks. Molecular characterization revealed the circulation of G IV and G I genotypes among swine and human population in Punjab state, respectively.
Collapse
Affiliation(s)
- M Bansal
- School of Public Health and Zoonoses, GADVASU, Ludhiana, India
| | - S Kaur
- School of Public Health and Zoonoses, GADVASU, Ludhiana, India
| | - D Deka
- School of Animal Biotechnology, GADVASU, Ludhiana, India
| | - R Singh
- School of Public Health and Zoonoses, GADVASU, Ludhiana, India
| | - J P S Gill
- School of Public Health and Zoonoses, GADVASU, Ludhiana, India
| |
Collapse
|
5
|
Pelosi E, Clarke I. Hepatitis E: a complex and global disease. EMERGING HEALTH THREATS JOURNAL 2017. [DOI: 10.3402/ehtj.v1i0.7069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- E Pelosi
- Department of Microbiology and Virology, Health Protection Agency, Southeast Regional Laboratory, Southampton General Hospital, Southampton, UK; and
| | - I Clarke
- Department of Molecular Microbiology, Southampton Medical School, Southampton General Hospital, Southampton, UK
| |
Collapse
|
6
|
Mirazo S, Mir D, Bello G, Ramos N, Musto H, Arbiza J. New insights into the hepatitis E virus genotype 3 phylodynamics and evolutionary history. INFECTION GENETICS AND EVOLUTION 2016; 43:267-73. [PMID: 27264728 DOI: 10.1016/j.meegid.2016.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 05/19/2016] [Accepted: 06/01/2016] [Indexed: 12/27/2022]
Abstract
Hepatitis E virus (HEV) is an emergent hepatotropic virus endemic mainly in Asia and other developing areas. However, in the last decade it has been increasingly reported in high-income countries. Human infecting HEV strains are currently classified into four genotypes (1-4). Genotype 3 (HEV-3) is the prevalent virus genotype and the mostly associated with autochthonous and sporadic cases of HEV in developed areas. The evolutionary history of HEV worldwide remains largely unknown. In this study we reconstructed the spatiotemporal and population dynamics of HEV-3 at global scale, but with particular emphasis in South America, where case reports have increased dramatically in the last years. To achieve this, we applied a Bayesian coalescent-based approach to a comprehensive data set comprising 97 GenBank HEV-3 sequences for which the location and sampling date was documented. Our phylogenetic analyses suggest that the worldwide genetic diversity of HEV-3 can be grouped into two main Clades (I and II) with a Ƭmrca dated in approximately 320years ago (95% HPD: 420-236years) and that a unique independent introduction of HEV-3 seems to have occurred in Uruguay, where most of the human HEV cases in South America have been described. The phylodynamic inference indicates that the population size of this virus suffered substantial temporal variations after the second half of the 20th century. In this sense and conversely to what is postulated to date, we suggest that the worldwide effective population size of HEV-3 is not decreasing and that frequently sources of error in its estimates stem from assumptions that the analyzed sequences are derived from a single panmictic population. Novel insights on the global population dynamics of HEV are given. Additionally, this work constitutes an attempt to further describe in a Bayesian coalescent framework, the phylodynamics and evolutionary history of HEV-3 in the South American region.
Collapse
Affiliation(s)
- Santiago Mirazo
- Sección Virología, Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
| | - Daiana Mir
- Laboratorio de AIDS & Imunologia Molecular, Instituto Oswaldo Cruz. Av. Brasil 4365, 21045900 Rio de Janeiro, Brazil
| | - Gonzalo Bello
- Laboratorio de AIDS & Imunologia Molecular, Instituto Oswaldo Cruz. Av. Brasil 4365, 21045900 Rio de Janeiro, Brazil
| | - Natalia Ramos
- Sección Virología, Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay
| | - Héctor Musto
- Laboratorio de Organización y Evolución del Genoma, Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400. Montevideo, Uruguay
| | - Juan Arbiza
- Sección Virología, Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay.
| |
Collapse
|
7
|
Owolodun OA, Gerber PF, Giménez-Lirola LG, Kwaga JKP, Opriessnig T. First report of hepatitis E virus circulation in domestic pigs in Nigeria. Am J Trop Med Hyg 2014; 91:699-704. [PMID: 25002299 DOI: 10.4269/ajtmh.14-0144] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Hepatitis E virus (HEV) is an important cause of acute hepatitis in humans. Zoonotic transmission between pigs and humans has been confirmed. Human HEV infection is common in Nigeria; however, characterization of HEV infection in other species was lacking. The objective of this study was to investigate HEV infection in Nigerian pigs. A total of 286 serum samples from six states in Nigeria were tested for presence of anti-HEV IgG. Ninety fecal samples from one of these states (Plateau State) were tested for presence of HEV RNA. The overall prevalence of anti-HEV IgG-positive or suspect-positive pigs was 55.6% (159 of 286) with regional prevalence rates ranging from 36% (9 of 25; Delta State) to 88% (22 of 25; Taraba State). The overall HEV RNA prevalence rate was 76.7% (69 of 90). All polymerase chain reaction-positive samples belonged to HEV genotype 3 based on sequencing. The results indicate that HEV genotype 3 infection is widespread in Nigerian pigs.
Collapse
Affiliation(s)
- Olajide A Owolodun
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa; Applied Biotechnology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria; Department Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Priscilla F Gerber
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa; Applied Biotechnology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria; Department Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Luis G Giménez-Lirola
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa; Applied Biotechnology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria; Department Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Jacob K P Kwaga
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa; Applied Biotechnology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria; Department Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Tanja Opriessnig
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa; Applied Biotechnology Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria; Department Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| |
Collapse
|
8
|
Zehender G, Ebranati E, Lai A, Luzzago C, Paladini S, Tagliacarne C, Galli C, Galli M, Ciccozzi M, Zanetti AR, Romanò L. Phylogeography and phylodynamics of European genotype 3 hepatitis E virus. INFECTION GENETICS AND EVOLUTION 2014; 25:138-43. [PMID: 24787998 DOI: 10.1016/j.meegid.2014.04.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/18/2014] [Accepted: 04/20/2014] [Indexed: 01/22/2023]
Abstract
Hepatitis E virus is classified into four genotypes that have different geographical and host distributions. The main cause of sporadic autochthonous type E acute hepatitis in developed countries is genotype 3, which has a worldwide distribution and widely infects pigs. The aim of this study was to make hypotheses concerning the origin and global dispersion routes of this genotype by reconstructing the spatial and temporal dynamics of 208 HEV genotype 3 ORF-2 sequences (retrieved from public databases) isolated in different geographical areas. The evolutionary rates, time of the most recent common ancestors (tMRCAs), epidemic growth and phylogeography of HEV-3 were co-estimated using a MCMC Bayesian method. The maximum clade credibility tree showed the existence of two distinct main clades: clade A, which consists of only European subtypes (HEV-3e and 3f), and clade B, which consists of European subtype 3c and all of the Asian subtypes (3a, 3b and 3d) sharing a common ancestor, which most probably existed in Asia in 1920s. All of the North American isolates belonged to Asian subtype 3a. On the basis of our time-scaled phylogeographical reconstruction, we hypothesise that after originating in the early 1800s in Europe, HEV reached Asia in the first decades of 1900, and then moved to America probably in the 1970s-1980s. Analysis of the skyline plot showed a sharp increase of the number of infections between the 1980s and 2005, thus suggesting the intervention of new and highly efficient routes of transmission possibly related to changes in the pig industry.
Collapse
Affiliation(s)
- Gianguglielmo Zehender
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy.
| | - Erika Ebranati
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy
| | - Alessia Lai
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy
| | - Camilla Luzzago
- Department of Veterinary Science and Public Health, University of Milan, Milan, Italy
| | - Sara Paladini
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Catia Tagliacarne
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Cristina Galli
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Massimo Galli
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy
| | - Massimo Ciccozzi
- Department of Infectious, Parasitic, and Immunomediated Disease, National Institute of Health, Rome, Italy; University Biomedical Campus, Rome, Italy
| | | | - Luisa Romanò
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| |
Collapse
|
9
|
Lu YH, Qian HZ, Hu AQ, Ren H, Qin X, Jiang QW, Zheng YJ. Duration of viraemia in Chinese acute sporadic hepatitis E. Eur J Clin Microbiol Infect Dis 2013; 33:755-9. [PMID: 24241947 DOI: 10.1007/s10096-013-2007-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 10/21/2013] [Indexed: 01/15/2023]
Abstract
Acute sporadic hepatitis E (ASHE) cases induced by hepatitis E virus genotype 4 (HEV-4) are increasing in China. Our study aimed to estimate the duration of HEV-4 viraemia in Chinese ASHE. A total of 619 serum specimens from 499 ASHE patients were examined for the presence of HEV RNA. The association between viraemia detection and serum sampling time was compared between subtypes. The cumulative probability of HEV viraemia detection was determined using Kaplan-Meier survival analysis, and the viraemia duration was estimated. A total of 42.7 % of serum specimens were positive for HEV RNA and all the isolated strains were identified as genotype 4 and subsequently assigned to five subtypes. Among the patients infected with subtypes 4d and 4i, the time interval from the initiation of clinical symptoms to serum specimen sampling was shorter than that among the patients with subtypes 4a, 4b and 4h. Kaplan-Meier analysis was conducted with 101 sequential specimens as well as with both 101 sequential specimens and 236 single negative specimens. The cumulative probability of HEV-4 viraemia detection was estimated to decline quickly to approximately 10 % within 32 days after the initiation of clinical symptoms and then to decline very slowly to 5 % by the 41st day and to zero by the 131st day. The majority of ASHE cases maintain detectable HEV-4 viraemia within one month after onset, whereas a small portion of cases maintain long-term viraemia and may act as a reservoir for further transmission.
Collapse
Affiliation(s)
- Y-H Lu
- Key Laboratory of Public Health Safety of Ministry of Education-Department of Epidemiology, Fudan University School of Public Health, 138 Yi Xue Yuan Road, Shanghai, 200032, China
| | | | | | | | | | | | | |
Collapse
|
10
|
Wu F, Wang M, Tian D. Serum from patients with hepatitis E virus-related acute liver failure induces human liver cell apoptosis. Exp Ther Med 2013; 7:300-304. [PMID: 24348810 PMCID: PMC3861037 DOI: 10.3892/etm.2013.1398] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 11/01/2013] [Indexed: 12/27/2022] Open
Abstract
The pathogenesis of acute liver failure has not been fully elucidated. The present study investigated the effects of the serum from patients with hepatitis E virus (HEV)-related acute liver failure on human liver cell survival and apoptosis, and evaluated the protective effects of anti-lipopolysaccharide(LPS) antibody recognizing core polysaccharide against acute liver failure serum-induced apoptosis. Serum was collected from patients with HEV-related acute liver failure. The levels of endotoxin (LPS) in the serum were measured using a quantitative tachypleus amebocyte lysate endotoxin detection kit with a chromogenic endpoint. Serum with a mean concentration of LPS was incubated with L02 human liver cells and the rate of apoptosis was detected by flow cytometry. The apoptotic rate was also evaluated in liver cells incubated with antibody and the HEV-related acute liver failure serum. The results indicated that the concentration of LPS in the serum of patients with HEV-related acute liver failure was 0.26±0.02 EU/ml, which was significantly higher than that of the control group (P<0.05). The rate of apoptosis in the human liver cells induced by acute liver failure serum was 5.83±0.42%, which was significantly increased compared with that in the cells treated with the serum of healthy individuals (P<0.05). The apoptotic rate of the cells incubated with antibody and the acute liver failure serum was 5.53±0.51%, which was lower than that of the cells incubated with acute liver failure serum alone (P>0.05). These results indicate that the serum of patients with HEV-related acute liver failure induces the apoptosis of human liver cells. LPS may be directly involved in the apoptosis of human liver cells. Moreover, the presence of the antibody did not significantly reduce the level of apoptosis of liver cells exposed to HEV-related acute liver failure serum.
Collapse
Affiliation(s)
- Fan Wu
- Department of Infectious Disease, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Minxin Wang
- Department of Infectious Disease, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Deying Tian
- Department of Infectious Disease, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| |
Collapse
|
11
|
Nakano T, Takahashi K, Arai M, Okano H, Kato H, Ayada M, Okamoto H, Mishiro S. Identification of European-type hepatitis E virus subtype 3e isolates in Japanese wild boars: Molecular tracing of HEV from swine to wild boars. INFECTION GENETICS AND EVOLUTION 2013; 18:287-98. [PMID: 23770142 DOI: 10.1016/j.meegid.2013.06.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 06/01/2013] [Accepted: 06/03/2013] [Indexed: 12/13/2022]
|
12
|
Seasonal pattern of hepatitis E virus prevalence in swine in two different geographical areas of China. Epidemiol Infect 2013; 141:2403-9. [PMID: 23388392 DOI: 10.1017/s0950268813000113] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We studied seasonal patterns of swine hepatitis E virus (HEV) infection in China. From 2008 to 2011, 4200 swine bile specimens were collected for the detection of HEV RNA. A total of 92/2400 (3·83%) specimens in eastern China and 47/1800 (2·61%) specimens in southwestern China were positive for HEV. Seasonal patterns differing by geographical area were suggested. In eastern China, the major peak of HEV RNA prevalence was during March-April, with a minor peak during September-October, and a dip during July-August. In southwestern China, the peak was during September-October and the dip during March-April. The majority of subtype 4a cases (63/82, 76·83%) were detected in the first half of the year, while the majority of subtype 4b cases (26/29, 89·66%) were concentrated in the second half of the year, suggesting that different subtypes contribute to different peaks. Our results indicate that the distribution of HEV subtypes is associated with seasonal patterns.
Collapse
|
13
|
Replication of hepatitis E virus in three-dimensional cell culture. J Virol Methods 2013; 187:327-32. [DOI: 10.1016/j.jviromet.2012.10.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 06/18/2012] [Accepted: 10/23/2012] [Indexed: 12/15/2022]
|
14
|
Lu YH, Qian HZ, Qin X, Jiang QW, Zheng YJ. Subtypes of genotype 3 hepatitis E virus in pigs. Vet J 2013; 197:509-11. [PMID: 23357066 DOI: 10.1016/j.tvjl.2012.12.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 12/20/2012] [Accepted: 12/26/2012] [Indexed: 01/25/2023]
Abstract
The prevalence of hepatitis E virus (HEV) RNA in faecal and bile samples from pigs in abattoirs in Eastern and South Western China from 2006 to 2011 was determined by reverse transcriptase PCR. HEV-3 was detected in 4/5952 (0.07%) pigs and HEV-4 was detected in 287/5952 (4.8%) pigs. Two HEV-3 subtype 3a strains from South Western China had 87.1-89.7% sequence identity. Two HEV-3 subtype 3b strains from Eastern China had 91.8-93.8% sequence identity and were similar to strains reported previously in Eastern and Central China. The distinct subtypes of HEV-3 in different regions of China suggested multiple origins of HEV infection.
Collapse
Affiliation(s)
- Yi-Han Lu
- Key Laboratory of Public Health Safety of the Ministry of Education, Department of Epidemiology, Fudan University School of Public Health, Shanghai 200032, China
| | | | | | | | | |
Collapse
|
15
|
Nakano T, Takahashi K, Pybus OG, Hashimoto N, Kato H, Okano H, Kobayashi M, Fujita N, Shiraki K, Takei Y, Ayada M, Arai M, Okamoto H, Mishiro S. New findings regarding the epidemic history and population dynamics of Japan-indigenous genotype 3 hepatitis E virus inferred by molecular evolution. Liver Int 2012; 32:675-88. [PMID: 22181032 DOI: 10.1111/j.1478-3231.2011.02728.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Accepted: 11/22/2011] [Indexed: 02/13/2023]
Abstract
BACKGROUND Since previous studies have investigated the population dynamics of Japan-indigenous genotype 3 hepatitis E virus (HEV) using virus sequences, more nucleotide sequences have been determined, and new techniques have been developed for such analysis. AIMS To prevent future hepatitis E epidemic in Japan, this study aimed to elucidate the cause of past HEV expansion. METHODS The epidemic history of Japan-indigenous genotype 3 HEV was determined using the coalescent analysis framework. Bayesian skyline plot (BSP) and Bayesian estimate of phylogeny with relaxed molecular clock models were calculated using Markov chain Monte Carlo sampling. RESULTS Japan-indigenous strains consist of New World strains (subtype 3a), Japanese strains (3b) and European strains (3e). The oldest lineage, 3b, appeared around 1929. Lineages 3a and 3e appeared around 1960. BSPs indicated similar radical population growth of the 3a and 3b lineages from 1960 to 1980. CONCLUSIONS Population dynamics of the three lineages shared some common characteristics, but had distinguishing features. The appearance of 3a and 3e lineages coincides with the increase of large-race pig importation from Europe and the USA after 1960. The epidemic phase of 3a and 3b strains from 1960 to 1980 could be related to increased opportunity for HEV infection arising from large-scale pig breeding since 1960. Our observations revealed new findings concerning the close relationship between the epidemic history of Japan-indigenous genotype 3 HEV and the improvement of the Japanese pig industry. Infection control in pig farms should be an effective method of preventing HEV infection in humans.
Collapse
Affiliation(s)
- Tatsunori Nakano
- Department of Internal Medicine, Fujita Health University Nanakuri Sanatorium, Mie, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Purdy MA, Khudyakov YE. The molecular epidemiology of hepatitis E virus infection. Virus Res 2011; 161:31-9. [PMID: 21600939 DOI: 10.1016/j.virusres.2011.04.030] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 03/23/2011] [Accepted: 04/29/2011] [Indexed: 12/11/2022]
Abstract
Molecular characterization of various hepatitis E virus (HEV) strains circulating among humans and animals (particularly swine, deer and boars) in different countries has revealed substantial genetic heterogeneity. The distinctive four-genotype distribution worldwide of mammalian HEV and varying degrees of genetic relatedness among local strains suggest a long and complex evolution of HEV in different geographic regions. The population expansion likely experienced by mammalian HEV in the second half of the 20th century is consistent with an extensive genetic divergence of HEV strains and high prevalence of HEV infections in many parts of the world, including developed countries. The rate and mechanisms of human-to-human transmission and zoonotic transmission to humans vary geographically, thus contributing to the complexity of HEV molecular evolution.
Collapse
Affiliation(s)
- Michael A Purdy
- Centers for Disease Control and Prevention, National Center for HIV/Hepatitis/STD/TB Prevention, Division of Viral Hepatitis, Atlanta, GA 30333, USA.
| | | |
Collapse
|
17
|
Khan A, Tanaka Y, Kurbanov F, Elkady A, Abbas Z, Azam Z, Subhan A, Raza S, Hamid S, Jafri W, Shih J, Xia N, Takahashi K, Mishiro S, Mizokami M. Investigating an outbreak of acute viral hepatitis caused by hepatitis E virus variants in Karachi, South Pakistan. J Med Virol 2011; 83:622-629. [PMID: 21328376 DOI: 10.1002/jmv.22036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
Hepatitis E is a classic water-borne disease in developing countries. Detection of anti-HEV IgM and IgG antibodies, in addition to HEV RNA are useful epidemiological markers in diagnosis of hepatitis E. This study was conducted to investigate an outbreak of acute viral hepatitis in South-Pakistan. Anti-HEV IgM and IgG were assessed comparatively with serological kits manufactured by Abbott, Cosmic, TGH, and Wantai, selecting HEV RNA as reference assay. Molecular evolutionary analysis was performed by phylogeny and HEV spread time analysis by Bayesian Coalescent Theory approach. Of the 89 patients, 24 (26.9%) did not have acute hepatitis viral marker. Of the remaining 65 cases, 4 (6.1%) were positive for anti-HAV IgM, one (1.5%) for anti-HBc IgM, 2 (3%) for HCV, 53 (81.5%) for anti-HEV IgM, and 5 (7.7%) were hepatitis-negative. The Wantai test was 100% sensitive and specific followed by Cosmic (98.1% and 100%), TGH (98.1% and 97.2%) and Abbott (79.2% and 83.3%). Two HEV variant strains were detected by phylogeny responsible for this acute hepatitis outbreak. Estimates on demographic history of HEV showed that HEV in Pakistan has remained at a steady nonexpanding phase from around 1970 to the year 2005, in which it expanded explosively with the emergence of new HEV variants. In conclusion, the limited sensitivity of available assay (Abbott anti-HEV EIA) may be a concern in HEV diagnosis in Pakistan. This study cautions that the dissemination of the variant strains to other areas of Pakistan may lead to explosive HEV outbreaks.
Collapse
Affiliation(s)
- Anis Khan
- Department of Virology and Liver Unit, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Dohmen K, Onohara SY, Tanaka H, Haruno M, Shimoda S, Kang JH, Ishii K, Takahashi K. Molecular epidemiological analysis of hepatitis A virus strain separated in Fukuoka 2010-the similarity with the strain from a patient infected in Borneo (Kalimantan) island 1999. ACTA ACUST UNITED AC 2011. [DOI: 10.2957/kanzo.52.497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
19
|
Purdy MA, Khudyakov YE. Evolutionary history and population dynamics of hepatitis E virus. PLoS One 2010; 5:e14376. [PMID: 21203540 PMCID: PMC3006657 DOI: 10.1371/journal.pone.0014376] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 11/24/2010] [Indexed: 12/19/2022] Open
Abstract
Background Hepatitis E virus (HEV) is an enterically transmitted hepatropic virus. It segregates as four genotypes. All genotypes infect humans while only genotypes 3 and 4 also infect several animal species. It has been suggested that hepatitis E is zoonotic, but no study has analyzed the evolutionary history of HEV. We present here an analysis of the evolutionary history of HEV. Methods and Findings The times to the most recent common ancestors for all four genotypes of HEV were calculated using BEAST to conduct a Bayesian analysis of HEV. The population dynamics for genotypes 1, 3 and 4 were analyzed using skyline plots. Bayesian analysis showed that the most recent common ancestor for modern HEV existed between 536 and 1344 years ago. The progenitor of HEV appears to have given rise to anthropotropic and enzootic forms of HEV, which evolved into genotypes 1 and 2 and genotypes 3 and 4, respectively. Population dynamics suggest that genotypes 1, 3 and 4 experienced a population expansion during the 20th century. Genotype 1 has increased in infected population size ∼30–35 years ago. Genotype 3 and 4 have experienced an increase in population size starting late in the 19th century until ca.1940-45, with genotype 3 having undergone additional rapid expansion until ca.1960. The effective population size for both genotype 3 and 4 rapidly declined to pre-expansion levels starting in ca.1990. Genotype 4 was further examined as Chinese and Japanese sequences, which exhibited different population dynamics, suggesting that this genotype experienced different evolutionary history in these two countries. Conclusions HEV appears to have evolved through a series of steps, in which the ancestors of HEV may have adapted to a succession of animal hosts leading to humans. Analysis of the population dynamics of HEV suggests a substantial temporal variation in the rate of transmission among HEV genotypes in different geographic regions late in the 20th Century.
Collapse
Affiliation(s)
- Michael A Purdy
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
| | | |
Collapse
|
20
|
Frost SDW, Volz EM. Viral phylodynamics and the search for an 'effective number of infections'. Philos Trans R Soc Lond B Biol Sci 2010; 365:1879-90. [PMID: 20478883 PMCID: PMC2880113 DOI: 10.1098/rstb.2010.0060] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Information on the dynamics of the effective population size over time can be obtained from the analysis of phylogenies, through the application of time-varying coalescent models. This approach has been used to study the dynamics of many different viruses, and has demonstrated a wide variety of patterns, which have been interpreted in the context of changes over time in the ‘effective number of infections’, a quantity proportional to the number of infected individuals. However, for infectious diseases, the rate of coalescence is driven primarily by new transmissions i.e. the incidence, and only indirectly by the number of infected individuals through sampling effects. Using commonly used epidemiological models, we show that the coalescence rate may indeed reflect the number of infected individuals during the initial phase of exponential growth when time is scaled by infectivity, but in general, a single change in time scale cannot be used to estimate the number of infected individuals. This has important implications when integrating phylogenetic data in the context of other epidemiological data.
Collapse
Affiliation(s)
- Simon D W Frost
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, Cambridgeshire CB3 0ES, UK.
| | | |
Collapse
|
21
|
Lam TTY, Hon CC, Tang JW. Use of phylogenetics in the molecular epidemiology and evolutionary studies of viral infections. Crit Rev Clin Lab Sci 2010; 47:5-49. [PMID: 20367503 DOI: 10.3109/10408361003633318] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Since DNA sequencing techniques first became available almost 30 years ago, the amount of nucleic acid sequence data has increased enormously. Phylogenetics, which is widely applied to compare and analyze such data, is particularly useful for the analysis of genes from rapidly evolving viruses. It has been used extensively to describe the molecular epidemiology and transmission of the human immunodeficiency virus (HIV), the origins and subsequent evolution of the severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV), and, more recently, the evolving epidemiology of avian influenza as well as seasonal and pandemic human influenza viruses. Recent advances in phylogenetic methods can infer more in-depth information about the patterns of virus emergence, adding to the conventional approaches in viral epidemiology. Examples of this information include estimations (with confidence limits) of the actual time of the origin of a new viral strain or its emergence in a new species, viral recombination and reassortment events, the rate of population size change in a viral epidemic, and how the virus spreads and evolves within a specific population and geographical region. Such sequence-derived information obtained from the phylogenetic tree can assist in the design and implementation of public health and therapeutic interventions. However, application of many of these advanced phylogenetic methods are currently limited to specialized phylogeneticists and statisticians, mainly because of their mathematical basis and their dependence on the use of a large number of computer programs. This review attempts to bridge this gap by presenting conceptual, technical, and practical aspects of applying phylogenetic methods in studies of influenza, HIV, and SCoV. It aims to provide, with minimal mathematics and statistics, a practical overview of how phylogenetic methods can be incorporated into virological studies by clinical and laboratory specialists.
Collapse
Affiliation(s)
- Tommy Tsan-Yuk Lam
- School of Biological Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | | | | |
Collapse
|
22
|
Kawamura K, Kobayashi Y, Takahashi K, Souda K, Sumiyoshi S, Kawata K, Takahashi Y, Makino S, Noritake H, Nakamura H, Abe N, Arai M. Three cases of hepatitis E after eating deer meat or wild boar liver in West Shizuoka, Japan. ACTA ACUST UNITED AC 2010. [DOI: 10.2957/kanzo.51.418] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
23
|
Kaba M, Colson P, Musongela JP, Tshilolo L, Davoust B. Detection of hepatitis E virus of genotype 3 in a farm pig in Kinshasa (Democratic Republic of the Congo). INFECTION GENETICS AND EVOLUTION 2009; 10:154-7. [PMID: 19800029 DOI: 10.1016/j.meegid.2009.09.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Revised: 09/18/2009] [Accepted: 09/22/2009] [Indexed: 01/07/2023]
Abstract
Autochthonous hepatitis E is an emerging disease in industrialized countries where a growing body of data indicates that pigs represent a reservoir for hepatitis E virus (HEV) of genotype 3 or 4. In Africa, only HEV genotypes 1 and 2 have been identified in hepatitis E outbreaks as well as in sporadic cases. We aimed to investigate whether commercial pigs in sub-Saharan Africa might represent an HEV reservoir using molecular assays. Faecal samples from 40 pigs of the Pietrain race housed in a farm in Kinshasa (Democratic Republic of the Congo) were tested using in-house real-time reverse transcription (RT)-PCR and sequencing assays. HEV RNA was detected in faeces of one (2.5%) pig, and the HEV sequence obtained from this pig was classified genotype 3c, and was genetically related to human HEV sequences from France (89-92% nucleotide similarity) and pig HEV sequences from The Netherlands (88-91% nucleotide similarity). Epidemiological investigations revealed that Kinshasa farm pigs tested in the present study are descendants of pigs imported from Belgium in 2002, suggesting that pig HEV genotype 3c recovered in our study may have been imported from Belgium to Democratic Republic of the Congo. Our findings, although needing to be confirmed in further studies, also suggest that pigs in sub-Saharan Africa may be an HEV reservoir.
Collapse
Affiliation(s)
- Mamadou Kaba
- URMITE CNRS UMR 6236 IRD198, Facultés de Médecine et de Pharmacie, Université de Méditerranée, 27 boulevard Jean Moulin, 13385 Marseille cedex 05, France
| | | | | | | | | |
Collapse
|
24
|
Bilic I, Jaskulska B, Basic A, Morrow CJ, Hess M. Sequence analysis and comparison of avian hepatitis E viruses from Australia and Europe indicate the existence of different genotypes. J Gen Virol 2009; 90:863-873. [PMID: 19264623 DOI: 10.1099/vir.0.007179-0] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Avian hepevirus infections were detected in chickens suffering from big liver and spleen disease or hepatitis-splenomegaly syndrome in Australia, the USA and Europe. Available data indicate their genetic relationship to mammalian hepatitis E virus (HEV). In the present study, the near-complete genomic sequences of an Australian and a European isolate of avian hepatitis E virus (avian HEV) are reported for the first time. Furthermore, the phylogenetic relationship to other avian HEVs is determined. Sequence analyses of these isolates identified major genetic differences among avian HEVs. Most of them are located within the open reading frame (ORF)1 region, although only a few lie within conserved motifs of predicted domains. Non-silent mutations in the ORF2 region suggest the presence of potentially different epitopes among avian HEV isolates. Finally, phylogenetic analysis confirmed the distant relationship to mammalian HEV and additionally suggested that the avian HEVs can be separated into three different genotypes: 1 (Australia), 2 (USA) and 3 (Europe), indicating a geographical distribution pattern.
Collapse
Affiliation(s)
- Ivana Bilic
- Clinic for Avian, Reptile and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria
| | - Barbara Jaskulska
- Clinic for Avian, Reptile and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria
| | - Ana Basic
- Clinic for Avian, Reptile and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria
| | | | - Michael Hess
- Clinic for Avian, Reptile and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria
| |
Collapse
|
25
|
Sugawara N, Yawata A, Takahashi K, Abe N, Arai M. The third case of fulminant hepatitis associated with "Kitami/Abashiri strain" of hepatitis E virus genotype 4. ACTA ACUST UNITED AC 2009. [DOI: 10.2957/kanzo.50.473] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
26
|
Toyoda K, Furusyo N, Takeoka H, Murata M, Sawayama Y, Hayashi J. Epidemiological study of hepatitis E virus infection in the general population of Okinawa, Kyushu, Japan. J Gastroenterol Hepatol 2008; 23:1885-90. [PMID: 19120876 DOI: 10.1111/j.1440-1746.2008.05568.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND AIM The aim of this study was to investigate the prevalence of hepatitis E virus (HEV) infection in the general population of Japan by determining presence of the antibody to HEV (anti-HEV). METHODS The prevalence of HEV infection was determined by positivity of serum antibody to HEV (anti-HEV). RESULTS On retrospective analysis, a significant decrease in anti-HEV prevalence was found in Okinawa healthy residents from 1995 (15.8%) to 2005 (5.5%) (P < 0.0001). In 2005, the anti-HEV prevalence was significantly higher in Okinawa wild boar hunters (25.3%) than in the residents (male 7.7% and female 4.1%) (P < 0.0001). A significant difference was found in the history of consumption of undercooked or raw boar meat between anti-HEV positive and negative hunters (100% vs 64.3%) (P = 0.0018). CONCLUSIONS In conclusion, the anti-HEV prevalence has decreased in the residents of this area, but HEV infection has continued at a high rate in the hunters through the custom of eating undercooked or raw boar meat.
Collapse
Affiliation(s)
- Kazuhiro Toyoda
- Department of Environmental Medicine and Infectious Disease, Kyushu University, Fukuoka, Japan
| | | | | | | | | | | |
Collapse
|
27
|
Pelosi E, Clarke I. Hepatitis E: a complex and global disease. EMERGING HEALTH THREATS JOURNAL 2008; 1:e8. [PMID: 22460217 PMCID: PMC3167588 DOI: 10.3134/ehtj.08.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 03/12/2008] [Accepted: 04/10/2008] [Indexed: 12/13/2022]
Abstract
Thirty years after its discovery, the hepatitis E virus (HEV) continues to represent a major public health problem in developing countries. In developed countries, it has emerged as a significant cause of non-travel-associated acute hepatitis. HEV infects a wide range of mammalian species and a key reservoir worldwide appears to be swine. Genomic sequence similarity between some human HEV genotypes and swine HEV strains has been identified and we know that humans can acquire HEV infection from animals. Although for the most part the clinical course of HEV infection is asymptomatic or mild, significant risk of serious disease exists in pregnant women and those with chronic liver disease. In addition, there are data on the threat of chronic infections in immunocompromised patients. Beyond management of exposure by public health measures, recent data support that active immunisation can prevent hepatitis E, highlighting the need for vaccination programmes. Here we review the current knowledge on HEV, its epidemiology, and the management and prevention of human disease.
Collapse
Affiliation(s)
- E Pelosi
- Department of Microbiology and Virology, Health Protection Agency, Southeast Regional Laboratory, Southampton General Hospital, Southampton, UK
| | | |
Collapse
|
28
|
Elkady A, Tanaka Y, Kurbanov F, Hirashima N, Sugiyama M, Khan A, Kato H, Okumura A, Mizokami M. Evaluation of anti-hepatitis E virus (HEV) immunoglobulin A in a serological screening for HEV infection. J Gastroenterol 2007; 42:911-7. [PMID: 18008036 DOI: 10.1007/s00535-007-2109-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Accepted: 08/20/2007] [Indexed: 02/04/2023]
Abstract
BACKGROUND Several formulations of serological diagnostic kits were developed recently in Japan for detecting hepatitis E virus (HEV) infection. The present study was conducted to evaluate a novel anti-HEV serological kit based on detection of class A immunoglobulin antibody (anti-HEV IgA). METHODS Serum samples from 81 acute hepatitis (AH) and 112 chronic hepatitis (CH) patients were tested for anti-HEV IgG, anti-HEV IgM, and anti-HEV IgA by enzyme immunoassay, and HEV RNA was detected by reverse transcription-polymerase chain reaction. RESULTS Eight of 81 (9.9%) AH patients were positive for anti-HEV IgG; 6/81 (7.4%) were positive for anti-HEV IgM; and 3/81 (3.7%) were positive for anti-HEV IgA. HEV RNA was detected only in two patients, and both were positive for anti-HEV IgA and negative for hepatitis A, B, and C virus markers. Of 112 CH patients, reactivity to anti-HEV IgM and anti-HEV IgG was found in two and four patients, respectively. None of these six patients was positive for anti-HEV IgA or HEV RNA. For these six CH patients, serial serum samples stored during the clinical follow-up (1994-2003) were further subjected to anti-HEV IgG, IgM, IgA, and HEV RNA examinations. None of the examined stored samples was reactive for anti-HEV IgA or HEV RNA despite reactivity to anti-HEV IgM and IgG. CONCLUSIONS Serological examination for anti-HEV IgA together with IgM and IgG allows sensitive and specific determination of acute or past infection with HEV. Although its prevalence is low, HEV infection must be investigated in acute hepatitis patients even in nonendemic HEV countries.
Collapse
Affiliation(s)
- Abeer Elkady
- Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-ku, Nagoya 467-8601, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Michitaka K, Takahashi K, Furukawa S, Inoue G, Hiasa Y, Horiike N, Onji M, Abe N, Mishiro S. Prevalence of hepatitis E virus among wild boar in the Ehime area of western Japan. Hepatol Res 2007; 37:214-20. [PMID: 17362304 DOI: 10.1111/j.1872-034x.2007.00030.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
AIMS Transmission of hepatitis E virus (HEV) from wild boar to humans has been reported, particularly from Japan. We attempted to clarify this issue. METHODS We assessed the IgG class antibodies against HEV (anti-HEV) in serum samples taken from 406 boar living in the Ehime area of western Japan from 2001 to 2004, of which 392 were captured in the wild (wild-caught boar) and 14 had been kept in a breeding farm (bred boar). RESULTS Anti-HEV positive rate in the bred boar (10/14, 71.4%) was significantly higher than in the wild-caught boar (100/392, 25.5%) (P < 0.001). Of the 392 wild-caught boar, 12 (3.1%) were positive for HEV-RNA, 10 of which were then subjected to phylogenetic analyses by sequencing an 821-nt fragment within ORF1. All the 10 isolates segregated to genotype 3, and eight of them were mutually related to form a cluster. All the eight HEV isolates in this cluster were from the wild-caught boar living in one and the same habitat within the studied area, while the other two independent isolates were from different regions. CONCLUSION HEV infection is endemic in wild boar in the Ehime area, and we should regard the wild boar as an important reservoir of HEV.
Collapse
Affiliation(s)
- Kojiro Michitaka
- Department of Gastroenterology and Metabology, Ehime University Graduate School of Medicine, Ehime, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Albetkova A, Drobeniuc J, Yashina T, Musabaev E, Robertson B, Nainan O, Favorov M. Characterization of hepatitis E virus from outbreak and sporadic cases in Turkmenistan. J Med Virol 2007; 79:1696-702. [PMID: 17854031 DOI: 10.1002/jmv.20991] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Large outbreaks and sporadic cases of hepatitis E have been reported in Central Asia. We assessed the genetic relatedness of hepatitis E virus (HEV) strains from outbreak and sporadic cases in Turkmenistan. Specimens from outbreak and sporadic cases of acute hepatitis non-A, non-B were tested by reverse transcription (RT)-polymerase chain reaction (PCR) to identify the presence of HEV RNA; nucleotide sequences were analyzed. HEV RNA was detected from 23/156 (15%) outbreak cases and 2/23 (9%) sporadic cases. The HEV outbreak isolates represented 14 unique sequences with genetic distances varying between 0.3% and 8.6%, 12 of which were closely related, with distances between 0.3% and 5.6%. Two unique sequences from outbreak cases 32 and 42 were closely related (99.7%) and shared 91.8-93.4% of sequence with the other 12 strains. The two strains were closely related to the previously published isolates from Burma (99.7-100%) and India-Madras (95.7-96.1%). The two 1994 sporadic HEV strains were 97.4% distinct, wile revealing 91.4-94.1% homology to 1985 strains, and 94.4-94.7% to HEV from the neighboring China and Pakistan. Genetic diversity of HEV that caused the hepatitis E outbreak in Turkmenistan in 1985 suggests heterogeneity of viral sources. Sporadic hepatitis E that occurred in 1994 was caused by viral strains genetically distinct from those causing the outbreak in 1985, yet closely related to HEV from neighboring countries. The study suggests that circulation of a broad variety of strains of HEV may occur in Central Asia, regardless of international borders, presenting a significant public health threat to the population of the region.
Collapse
Affiliation(s)
- Adilya Albetkova
- CDC Central Asia Office, Division of International Health, Office of Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
PURPOSE OF REVIEW Hepatitis E, a disease transmitted by hepatitis E virus, is increasingly recognized as being indigenous to affluent, temperate-zone countries. Issues pertaining to disease acquisition and hepatitis E virus infection, particularly in Western countries, are reviewed and highlighted. RECENT FINDINGS Clinical hepatitis E in the West, as in Japan, manifests more commonly in older people (>60 years) and in men, but fulminant hepatitis appears less frequent than in Japan. There, specific gastronomic and culinary risk factors associated with disease are being identified, but in the West, data implicating hepatitis E as being foodborne have yet to emerge. While hepatitis E virus subgenomic sequences in Western case patients are found to be closely related to swine hepatitis E virus, a porcine linkage to their infection remains to be established. Weak associations between occupational contact with pigs and risk of infection have been noted. Findings from earlier studies implicating animals that cohabitate with humans as reservoirs, and sewage as vehicles of infection await confirmation. SUMMARY Hepatitis E indigenous to developed countries is a distinct clinico-epidemiological entity. Humans, animals, food and the environment contribute and interact to cause human disease, and to sustain hepatitis E virus endemicity and enzooticity.
Collapse
Affiliation(s)
- Chong Gee Teo
- Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
| |
Collapse
|
32
|
Hon CC, Lam TY, Drummond A, Rambaut A, Lee YF, Yip CW, Zeng F, Lam PY, Ng PTW, Leung FCC. Phylogenetic analysis reveals a correlation between the expansion of very virulent infectious bursal disease virus and reassortment of its genome segment B. J Virol 2006; 80:8503-9. [PMID: 16912300 PMCID: PMC1563883 DOI: 10.1128/jvi.00585-06] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infectious bursal disease virus (IBDV) is a birnavirus causing immunosuppressive disease in chickens. Emergence of the very virulent form of IBDV (vvIBDV) in the late 1980s dramatically changed the epidemiology of the disease. In this study, we investigated the phylogenetic origins of its genome segments and estimated the time of emergence of their most recent common ancestors. Moreover, with recently developed coalescence techniques, we reconstructed the past population dynamics of vvIBDV and timed the onset of its expansion to the late 1980s. Our analysis suggests that genome segment A of vvIBDV emerged at least 20 years before its expansion, which argues against the hypothesis that mutation of genome segment A is the major contributing factor in the emergence and expansion of vvIBDV. Alternatively, the phylogeny of genome segment B suggests a possible reassortment event estimated to have taken place around the mid-1980s, which seems to coincide with its expansion within approximately 5 years. We therefore hypothesize that the reassortment of genome segment B initiated vvIBDV expansion in the late 1980s, possibly by enhancing the virulence of the virus synergistically with its existing genome segment A. This report reveals the possible mechanisms leading to the emergence and expansion of vvIBDV, which would certainly provide insights into the scope of surveillance and prevention efforts regarding the disease.
Collapse
Affiliation(s)
- Chung-Chau Hon
- Department of Zoology, The University of Hong Kong, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Abstract
AIM: To study the significance of serum anti-hepatitis E virus (HEV) IgA in patients with hepatitis E.
METHODS: A new method was established to assay anti-HEV IgA, which could be detected in the middle phase of the infection. We compared anti-HEV IgA assay with anti-HEV IgM and anti-HEV IgG assay in sera from 60 patients with positive HEV-RNA.
RESULTS: The 60 patients with positive HEV-RNA had both anti-HEV IgA and anti-HEV IgM and 410 patients with negative HEV-RNA were used as control. Periodic serum samples obtained from 60 patients with hepatitis E were tested for HEV RNA, anti-HEV IgM, anti-HEV IgA and anti-HEV IgG. Their HEV-RNA was detectable in the serum until 20 ± 11 d. We used anti-HEV IgM and anti-HEV IgA assay to detect HEV infection and positive results were found in 90 ± 15 d and 120 ± 23 d respectively, the positive rate of anti-HEV IgA was higher than that of anti-HEV IgM and HEV-RNA (P <0.05).
CONCLUSION: The duration of anti-HEV IgA in serum is longer than that of anti-HEV IgM, and anti-HEV IgA assay is a good method to detect HEV infection.
Collapse
Affiliation(s)
- De-Ying Tian
- Department of Infectious Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Provice, China.
| | | | | |
Collapse
|
34
|
Abe T, Aikawa T, Akahane Y, Arai M, Asahina Y, Atarashi Y, Chayama K, Harada H, Hashimoto N, Hori A, Ichida T, Ikeda H, Ishikawa A, Ito T, Kang JH, Karino Y, Kato H, Kato M, Kawakami M, Kitajima N, Kitamura T, Masaki N, Matsubayashi K, Matsuda H, Matsui A, Michitaka K, Mihara H, Miyaji K, Miyakawa H, Mizuo H, Mochida S, Moriyama M, Nishiguchi S, Okada K, Saito H, Sakugawa H, Shibata M, Suzuki K, Takahashi K, Yamada G, Yamamoto K, Yamanaka T, Yamato H, Yano K, Mishiro S. Demographic, epidemiological, and virological characteristics of hepatitis E virus infections in Japan based on 254 human cases collected nationwide. ACTA ACUST UNITED AC 2006. [DOI: 10.2957/kanzo.47.384] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|