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Liu D, Liu B, He Z, Qiao C, Luo Q, Chen X, Wang X, Xiang H, Chen J, Zhang P, Huang Y, Wang G, Tan C, Cai R. Seroprevalence survey of Hepatitis E Virus in Domestic Pigs in Guangdong, China. Animals (Basel) 2024; 14:1861. [PMID: 38997973 PMCID: PMC11240697 DOI: 10.3390/ani14131861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 06/20/2024] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
The Hepatitis E virus (HEV) causes acute and chronic Hepatitis E and is a global public health concern. HEV genotypes 3 (HEV-3) and 4 (HEV-4) are common to humans and animals, and domestic pigs and wild boars have been identified as the main reservoirs. However, limited information is available on the status of HEV infection in pigs, particularly in the Guangdong Province, China. This study aimed to investigate the seroprevalence of HEV in pig farms within the Guangdong Province. A total of 1568 serum samples were collected from 25 farms and tested for anti-HEV IgG antibodies. Enzyme-linked immunosorbent assay (ELISA) results revealed that 57.53% (902/1568) of serum samples from 24 farms (24/25, 96%) were positive for anti-HEV IgG antibodies. Year, season, region, and age were all linked risk factors for HEV in Guangdong, with season and region showing more significant impacts. The results showing a high seroprevalence of HEV confirmed its circulation among domestic pigs in the Guangdong Province, China. The presence of this antibody indicates that HEV infection was or is present on farms, posing a risk of zoonotic transmission of HEV from pigs to exposed workers and from pork or organs to consumption.
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Affiliation(s)
- Dingyu Liu
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Baoling Liu
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Zhenwen He
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Changhong Qiao
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Qin Luo
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Xiangyu Chen
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Xiaohu Wang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Hua Xiang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Jing Chen
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Pian Zhang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Yuan Huang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Gang Wang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
| | - Chen Tan
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Rujian Cai
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (D.L.)
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Tsachev I, Gospodinova K, Pepovich R, Takova K, Kundurzhiev T, Zahmanova G, Kaneva K, Baymakova M. First Insight into the Seroepidemiology of Hepatitis E Virus (HEV) in Dogs, Cats, Horses, Cattle, Sheep, and Goats from Bulgaria. Viruses 2023; 15:1594. [PMID: 37515279 PMCID: PMC10385379 DOI: 10.3390/v15071594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 07/30/2023] Open
Abstract
In recent years, hepatitis E virus (HEV) infection has been found to be widespread among different animal species worldwide. In Bulgaria, high HEV seropositivity was found among pigs (60.3%), wild boars (40.8%), and East Balkan swine (82.5%). The aim of the present study was to establish the seroprevalence of HEV among dogs, cats, horses, cattle, sheep, and goats in Bulgaria. In total, 720 serum samples from six animal species were randomly collected: dogs-90 samples; cats-90; horses-180; cattle-180; sheep-90; and goats-90. The serum samples were collected from seven districts of the country: Burgas, Kardzhali, Pazardzhik, Plovdiv, Sliven, Smolyan, and Stara Zagora. The animal serum samples were tested for HEV antibodies using the commercial Wantai HEV-Ab ELISA kit (Beijing, China). The overall HEV seroprevalence among different animal species from Bulgaria was as follows: dogs-21.1%; cats-17.7%; horses-8.3%; cattle-7.7%; sheep-32.2%; and goats-24.4%. We found the lowest overall HEV seropositivity in Plovdiv district (6.2%; 4/64; p = 0.203) and Smolyan district (8.8%; 4/45; p = 0.129), vs. the highest in Pazardzhik district (21.6%; 29/134; p = 0.024) and Burgas district (28.8%; 26/90; p = 0.062). To the best of our knowledge, this is the first serological evidence of HEV infection in dogs, cats, horses, cattle, sheep, and goats from Bulgaria. We found high HEV seropositivity in small ruminants (sheep and goats), moderate seropositivity in pets (dogs and cats), and a low level of seropositivity in large animals (horses and cattle). Previous Bulgarian studies and the results of this research show that HEV infection is widespread among animals in our country. In this regard, the Bulgarian health authorities must carry out increased surveillance and control of HEV infection among animals in Bulgaria.
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Affiliation(s)
- Ilia Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
| | - Krasimira Gospodinova
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
| | - Roman Pepovich
- Department of Infectious Pathology, Hygiene, Technology and Control of Foods from Animal Origin, Faculty of Veterinary Medicine, University of Forestry, 1797 Sofia, Bulgaria
| | - Katerina Takova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria
| | - Todor Kundurzhiev
- Department of Occupational Medicine, Faculty of Public Health, Medical University, 1527 Sofia, Bulgaria
| | - Gergana Zahmanova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria
- Department of Technology Transfer and IP Management, Center of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria
| | - Kristin Kaneva
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
| | - Magdalena Baymakova
- Department of Infectious Diseases, Military Medical Academy, 1606 Sofia, Bulgaria
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Meester M, Tobias TJ, van den Broek J, Meulenbroek CB, Bouwknegt M, van der Poel WH, Stegeman A. Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms. One Health 2023; 16:100570. [PMID: 37363225 PMCID: PMC10288132 DOI: 10.1016/j.onehlt.2023.100570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 05/17/2023] [Accepted: 05/23/2023] [Indexed: 06/28/2023] Open
Abstract
Hepatitis E virus (HEV) can be transmitted from pigs to humans and cause liver inflammation. Pigs are a major reservoir of HEV and most slaughter pigs show evidence of infection by presence of antibodies (ELISA) or viral RNA (PCR). Reducing the number of HEV infected pigs at slaughter would likely reduce human exposure, yet how this can be achieved, is unknown. We aimed to identify and quantify the effect of biosecurity measures to deliver HEV negative batches of pigs to slaughter. A case-control study was performed with Dutch pig farms selected based on results of multiple slaughter batches. Case farms delivered at least one PCR and ELISA negative batch to slaughter (PCR-ELISA-), indicating absence of HEV infection, and control farms had the highest proportion of PCR and/or ELISA positive batches (PCR+ELISA+), indicating high within-farm transmission. Data about biosecurity and housing were collected via a questionnaire and an audit. Variables were selected by regularization (LASSO regression) and ranked, based the frequency of variable selection. The odds ratios (OR) for the relation between case-control status and the highest ranked variables were determined via grouped logistic regression. Thirty-five case farms, with 10 to 60% PCR-ELISA- batches, and 38 control farms with on average 40% PCR+ELISA+ batches, were included. Rubber and steel floor material in fattening pens had the highest ranking and increased the odds of a PCR-ELISA- batch by 5.87 (95%CI 3.03-11.6) and 7.13 (95%CI 3.05-16.9) respectively. Cleaning pig driving boards weekly (OR 1.99 (95%CI 1.07-3.80)), and fly control with predatory flies (OR 4.52 (95%CI 1.59-13.5)) were protective, whereas a long fattening period was a risk. This study shows that cleaning and cleanability of floors and fomites and adequate fly control are measures to consider for HEV control in infected farms. Yet, intervention studies are needed to confirm the robustness of these outcomes.
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Affiliation(s)
- Marina Meester
- Farm Animal Health Unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Tijs J. Tobias
- Farm Animal Health Unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
- Royal GD, Deventer, the Netherlands
| | - Jan van den Broek
- Farm Animal Health Unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Carmijn B. Meulenbroek
- Farm Animal Health Unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | | | | | - Arjan Stegeman
- Farm Animal Health Unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
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4
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Krumova-Valcheva GL, Di Bartolo I, Smith RP, Gyurova E, Mateva G, Milanov M, Dimitrova A, Burow E, Daskalov H. Detection of HEV RNA Using One-Step Real-Time RT-PCR in Farrow-to-Finish Pig Farms in Bulgaria. Pathogens 2023; 12:pathogens12050673. [PMID: 37242343 DOI: 10.3390/pathogens12050673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/28/2023] [Accepted: 04/29/2023] [Indexed: 05/28/2023] Open
Abstract
(1) Background: HEV is a zoonotic, foodborne pathogen. It is spread worldwide and represents a public health risk. The aim of this study was to evaluate the presence of HEV RNA in farrow-to-finish pig farms in different regions of Bulgaria; (2) Methods: Isolation of HEV RNA from pooled samples of feces was performed using a QIAamp® Viral RNA Mini Kit followed by HEV RNA detection using a single-step real-time RT-PCR with primers and probes targeting the ORF 3 HEV genome; (3) Results: HEV RNA was detected in 12 out of 32 tested farms in Bulgaria (37.5%). The overall percentage of HEV-positive pooled fecal samples was 10.8% (68 of 630 samples). HEV was detected mostly in pooled fecal samples from finisher pigs (66/320, 20.6%) and sporadically from dry sows (1/62, 1.6%) and gilts (1/248, 0.4%); (4) Conclusions: Our results confirm that HEV circulates in farrow-to-finish pig farms in Bulgaria. In our study, we found HEV RNA in pooled fecal samples from fattening pigs (4-6-months age), shortly before their transport to the slaughterhouse indicating a potential risk to public health. The possible circulation of HEV throughout pork production requires monitoring and containment measures.
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Affiliation(s)
| | - Ilaria Di Bartolo
- Departement of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, 00161 Roma, Italy
| | | | - Eva Gyurova
- National Centre for Food Safety, National Diagnostic and Research Veterinary Medical Institute, 1606 Sofia, Bulgaria
| | - Gergana Mateva
- National Centre for Food Safety, National Diagnostic and Research Veterinary Medical Institute, 1606 Sofia, Bulgaria
| | - Mihail Milanov
- National Centre for Food Safety, National Diagnostic and Research Veterinary Medical Institute, 1606 Sofia, Bulgaria
| | - Albena Dimitrova
- National Centre for Food Safety, National Diagnostic and Research Veterinary Medical Institute, 1606 Sofia, Bulgaria
| | - Elke Burow
- Department Biological Safety, Federal Institute for Risk Assessment, 12277 Berlin, Germany
| | - Hristo Daskalov
- National Centre for Food Safety, National Diagnostic and Research Veterinary Medical Institute, 1606 Sofia, Bulgaria
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5
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Tsachev I, Baymakova M, Bangieva D, Khezzani B, Kundurzhiev T, Valeva B, Pepovich R. Serological Searching for Hepatitis E Virus Infection Among Pig Liver Transudate from Bulgaria: An Alternative Method for Seroepidemiological Survey. Vector Borne Zoonotic Dis 2022; 22:596-599. [PMID: 36322875 DOI: 10.1089/vbz.2022.0041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Background: The aim of this research was to perform a seroepidemiological survey of hepatitis E virus (HEV) by an alternative method-serological establishment of the virus from pig liver transudate. This is the first such research in Bulgaria. Moreover, no studies have been conducted on HEV in pig liver in our country. Materials and Methods: A total of 90 liver samples from healthy pigs were collected from slaughterhouses in three parts of the country (Sofia, Lovech, and Stara Zagora districts). An equal number of samples (n = 30) were obtained from each district. Results: The overall HEV seropositivity was 67.7% of all 90 tested pig liver transudate samples; in Sofia district 20.0%, in Lovech district 90.0%, and in Stara Zagora district 93.3%. Conclusion: These data are similar to our previous serological studies for HEV in serum samples from industrial pigs, wild boars, and East Balkan swine. In this regard, testing the liver transudate could be a fine alternative method for seroepidemiological survey on HEV in swine.
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Affiliation(s)
- Ilia Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Magdalena Baymakova
- Department of Infectious Diseases, Military Medical Academy, Sofia, Bulgaria
| | - Desislava Bangieva
- Department of Food Quality and Safety and Veterinary Legislation, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Bachir Khezzani
- Department of Biology, Faculty of Nature and Life Sciences, University of El Oued, El Oued, Algeria.,Laboratory of Biology, Environment and Health (LBEH), Faculty of Nature and Life Sciences, University of El Oued, El Oued, Algeria
| | - Todor Kundurzhiev
- Department of Occupational Medicine, Faculty of Public Health, Medical University, Sofia, Bulgaria
| | - Betina Valeva
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Roman Pepovich
- Department of Infectious Pathology, Hygiene, Technology and Control of Foods from Animal Origin, Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria
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6
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Palombieri A, Tsachev I, Sarchese V, Fruci P, Di Profio F, Pepovich R, Baymakova M, Marsilio F, Martella V, Di Martino B. A Molecular Study on Hepatitis E Virus (HEV) in Pigs in Bulgaria. Vet Sci 2021; 8:vetsci8110267. [PMID: 34822640 PMCID: PMC8619608 DOI: 10.3390/vetsci8110267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 10/29/2021] [Accepted: 11/04/2021] [Indexed: 11/16/2022] Open
Abstract
Information on hepatitis E virus (HEV) strains circulating in animal reservoirs in Bulgaria is currently lacking. Herein, by screening HEV seropositive sera obtained from Bulgarian swine and wild boars, viral RNA was detected at high prevalence rate (28.2%) in industrial pigs. Sequence analysis of the partial polymerase (RdRp) region revealed the highest genetic correlation with HEVs of genotype (Gt) 3 identified in French and Dutch patients. For three such strains, a 700-bp fragment of the open reading frame 2 gene was generated. On phylogenetic analysis, the Bulgarian strains clustered tightly (93.8-98.3% nt) with human and animal HEVs classified within the Gt3 subtype c.
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Affiliation(s)
- Andrea Palombieri
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, 64100 Teramo, Italy; (A.P.); (V.S.); (P.F.); (F.D.P.); (F.M.)
| | - Ilia Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria;
| | - Vittorio Sarchese
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, 64100 Teramo, Italy; (A.P.); (V.S.); (P.F.); (F.D.P.); (F.M.)
| | - Paola Fruci
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, 64100 Teramo, Italy; (A.P.); (V.S.); (P.F.); (F.D.P.); (F.M.)
| | - Federica Di Profio
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, 64100 Teramo, Italy; (A.P.); (V.S.); (P.F.); (F.D.P.); (F.M.)
| | - Roman Pepovich
- Department of Infectious Pathology, Hygiene, Technology and Control of Foods from Animal Origin, Faculty of Veterinary Medicine, University of Forestry, 1797 Sofia, Bulgaria;
| | - Magdalena Baymakova
- Department of Infectious Diseases, Military Medical Academy, 1606 Sofia, Bulgaria;
| | - Fulvio Marsilio
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, 64100 Teramo, Italy; (A.P.); (V.S.); (P.F.); (F.D.P.); (F.M.)
| | - Vito Martella
- Department of Veterinary Medicine, Università Aldo Moro di Bari, 70010 Valenzano, Italy;
| | - Barbara Di Martino
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, 64100 Teramo, Italy; (A.P.); (V.S.); (P.F.); (F.D.P.); (F.M.)
- Correspondence:
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7
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Development and Optimization of an Enzyme Immunoassay to Detect Serum Antibodies against the Hepatitis E Virus in Pigs, Using Plant-Derived ORF2 Recombinant Protein. Vaccines (Basel) 2021; 9:vaccines9090991. [PMID: 34579228 PMCID: PMC8473109 DOI: 10.3390/vaccines9090991] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/27/2021] [Accepted: 08/31/2021] [Indexed: 12/16/2022] Open
Abstract
Hepatitis E is an emerging global disease, mainly transmitted via the fecal-oral route in developing countries, and in a zoonotic manner in the developed world. Pigs and wild boar constitute the primary Hepatitis E virus (HEV) zoonotic reservoir. Consumption of undercooked animal meat or direct contact with infected animals is the most common source of HEV infection in European countries. The purpose of this study is to develop an enzyme immunoassay (EIA) for the detection of anti-hepatitis E virus IgG in pig serum, using plant-produced recombinant HEV-3 ORF2 as an antigenic coating protein, and also to evaluate the sensitivity and specificity of this assay. A recombinant HEV-3 ORF2 110-610_6his capsid protein, transiently expressed by pEff vector in Nicotiana benthamiana plants was used to develop an in-house HEV EIA. The plant-derived HEV-3 ORF2 110-610_6his protein proved to be antigenically similar to the HEV ORF2 capsid protein and it can self-assemble into heterogeneous particulate structures. The optimal conditions for the in-house EIA (iEIA) were determined as follows: HEV-3 ORF2 110-610_6his antigen concentration (4 µg/mL), serum dilution (1:50), 3% BSA as a blocking agent, and secondary antibody dilution (1:20 000). The iEIA developed for this study showed a sensitivity of 97.1% (95% Cl: 89.9-99.65) and a specificity of 98.6% (95% Cl: 92.5-99.96) with a Youden index of 0.9571. A comparison between our iEIA and a commercial assay (PrioCHECK™ Porcine HEV Ab ELISA Kit, ThermoFisher Scientific, MA, USA) showed 97.8% agreement with a kappa index of 0.9399. The plant-based HEV-3 ORF2 iEIA assay was able to detect anti-HEV IgG in pig serum with a very good agreement compared to the commercially available kit.
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8
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Mrzljak A, Jemersic L, Savic V, Balen I, Ilic M, Jurekovic Z, Pavicic-Saric J, Mikulic D, Vilibic-Cavlek T. Hepatitis E Virus in Croatia in the "One-Health" Context. Pathogens 2021; 10:pathogens10060699. [PMID: 34199798 PMCID: PMC8227679 DOI: 10.3390/pathogens10060699] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 02/07/2023] Open
Abstract
Hepatitis E virus (HEV) is the most common cause of viral hepatitis globally. The first human case of autochthonous HEV infection in Croatia was reported in 2012, with the undefined zoonotic transmission of HEV genotype 3. This narrative review comprehensively addresses the current knowledge on the HEV epidemiology in humans and animals in Croatia. Published studies showed the presence of HEV antibodies in different population groups, such as chronic patients, healthcare professionals, voluntary blood donors and professionally exposed and pregnant women. The highest seroprevalence in humans was found in patients on hemodialysis in a study conducted in 2018 (27.9%). Apart from humans, different studies have confirmed the infection in pigs, wild boars and a mouse, indicating the interspecies transmission of HEV due to direct or indirect contact or as a foodborne infection. Continued periodical surveys in humans and animals are needed to identify the possible changes in the epidemiology of HEV infections.
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Affiliation(s)
- Anna Mrzljak
- Department of Gastroenterology and Hepatology, University Hospital Center Zagreb, 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia;
- Correspondence:
| | - Lorena Jemersic
- Department of Virology, Croatian Veterinary Institute, 10000 Zagreb, Croatia;
| | - Vladimir Savic
- Poultry Center, Croatian Veterinary Institute, 10000 Zagreb, Croatia;
| | - Ivan Balen
- Department of Gastroenterology and Endocrinology, General Hospital “Dr. Josip Bencevic”, 35000 Slavonski Brod, Croatia;
| | - Maja Ilic
- Department of Epidemiology, Croatian Institute of Public Health, 10000 Zagreb, Croatia;
| | - Zeljka Jurekovic
- Department of Medicine, Merkur University Hospital, 10000 Zagreb, Croatia;
| | - Jadranka Pavicic-Saric
- Department of Anestesiology, Reanimatology and Intensive Care, Merkur University Hospital, 10000 Zagreb, Croatia;
| | - Danko Mikulic
- Department of Abdominal and Transplant Surgery, Merkur University Hospital, 10000 Zagreb, Croatia;
| | - Tatjana Vilibic-Cavlek
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia;
- Department of Virology, Croatian Institute of Public Health, 10000 Zagreb, Croatia
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9
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Slukinova OS, Kyuregyan KK, Karlsen AA, Potemkin IA, Kichatova VS, Semenov SI, Stepanov KM, Rumyantseva TD, Mikhailov MI. Serological Evidence of Hepatitis E Virus Circulation Among Reindeer and Reindeer Herders. Vector Borne Zoonotic Dis 2021; 21:546-551. [PMID: 34010077 DOI: 10.1089/vbz.2020.2727] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Various deer species are infected with hepatitis E virus (HEV) and may be a source of zoonotic infection for humans. So far, HEV has not been isolated from reindeer and the role of this domesticated deer species in HEV transmission is unknown. We tested serum samples from 191 reindeer (Rangifer tarandus) and 86 adult reindeer herders from the circumpolar regions of Yakutia (Russian Federation) for anti-HEV and HEV RNA. Anti-HEV IgG prevalence was 12.0% (95% confidence interval [95% CI]: 8.1-17.5) in reindeer and 4.7% (95% CI: 1.5-11.7) in reindeer herders. The latter was similar to the positivity rate observed in adult residents of the city of Yakutsk, the capital of Yakutia, who do not have routine contact with reindeer (3.7% [19/519, 95% CI: 2.3-5.7]). No samples positive for HEV RNA were identified. The study provides evidence of HEV circulation in reindeer. Nevertheless, the low seroprevalence in reindeer herders indicate a low risk of zoonotic HEV infection.
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Affiliation(s)
- Olga S Slukinova
- Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia
| | - Karen K Kyuregyan
- Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia.,Department of Viral Hepatitis, Russian Medical Academy of Continuous Professional Education, Moscow, Russia
| | - Anastasiya A Karlsen
- Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia.,Department of Viral Hepatitis, Russian Medical Academy of Continuous Professional Education, Moscow, Russia
| | - Ilya A Potemkin
- Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia.,Department of Viral Hepatitis, Russian Medical Academy of Continuous Professional Education, Moscow, Russia
| | - Vera S Kichatova
- Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia.,Department of Viral Hepatitis, Russian Medical Academy of Continuous Professional Education, Moscow, Russia
| | - Sergey I Semenov
- Medical Institute of the North-Eastern Federal University Named After M.K. Ammosov, Yakutsk, Republic of Sakha (Yakutia), Russia
| | - Konstantin M Stepanov
- Arctic State Agrotechnological University, Yakutsk, Republic of Sakha (Yakutia), Russia
| | - Tatyana D Rumyantseva
- Arctic State Agrotechnological University, Yakutsk, Republic of Sakha (Yakutia), Russia
| | - Mikhail I Mikhailov
- Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia.,Department of Viral Hepatitis, Russian Medical Academy of Continuous Professional Education, Moscow, Russia
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10
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Seroprevalence of Hepatitis E Virus Infection among Blood Donors in Bulgaria. Viruses 2021; 13:v13030492. [PMID: 33809748 PMCID: PMC8002317 DOI: 10.3390/v13030492] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/12/2021] [Accepted: 03/15/2021] [Indexed: 02/07/2023] Open
Abstract
Hepatitis E virus (HEV) infection is widespread among domestic pigs, industrial swine, and wild boars in Bulgaria. The aim of the current research was to present the HEV seroprevalence among blood donors in Bulgaria. In the present study, 555 blood donors (479 males and 76 females) were enrolled from five districts in the country (Shumen, Pleven, Stara Zagora, Plovdiv, and Sofia districts). All blood samples were tested for anti-HEV IgG using the recomWell HEV IgG ELISA test (Mikrogen GmbH, Neuried, Germany). Each participating donor completed a short, structured, and specific questionnaire to document data on the current study. Anti-HEV IgG positive results were detected in 144 (25.9%) blood donors, including 129 (26.9%) males and 15 (19.7%) females. The established HEV seropositivity was 28.8% (23/80) in Shumen district, 23.2% (22/95) in Pleven district, 27.1% (38/140) in Stara Zagora district, 27.5% (44/160) in Plovdiv district, and 21.3% (17/80) in Sofia district. A high HEV seroprevalence was found for persons who declared that they were general hunters (48.7%; 19/39; p = 0.001) and hunters of wild boars (51.6%; 16/31; p = 0.001). We present the first seroprevalence rates of HEV infection in blood donors from Bulgaria. The results of our research showed high HEV seropositivity among blood donors.
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Tsachev I, Baymakova M, Marutsov P, Gospodinova K, Kundurzhiev T, Petrov V, Pepovich R. Seroprevalence of Hepatitis E Virus Infection Among Wild Boars in Western Bulgaria. Vector Borne Zoonotic Dis 2021; 21:441-445. [PMID: 33625897 DOI: 10.1089/vbz.2020.2756] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Scientific evidence indicates that hepatitis E virus (HEV) infection is a zoonotic disease. Domestic pigs and wild boars are the main animal reservoir for HEV worldwide. The aim of this study was to analyze the seroprevalence of HEV infection among wild boars in western Bulgaria. Serum samples from 240 wild boars from two regions of the country (northwestern and southwestern) were tested for anti-HEV Immunoglobulin G (IgG) antibodies. The overall HEV seroprevalence was 40.8% (98/240); northwestern region 40.0% (48/120); southwestern region 41.7% (50/120). HEV seropositivity in the southwestern region was higher than in the northwestern region: odds ratio = 1.071 (95% confidence interval: 0.640-1.793). This research provided the first seroprevalence study to HEV in wild boars from western Bulgaria.
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Affiliation(s)
- Ilia Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Magdalena Baymakova
- Department of Infectious Diseases, Military Medical Academy, Sofia, Bulgaria
| | - Plamen Marutsov
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Krasimira Gospodinova
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Todor Kundurzhiev
- Department of Occupational Medicine, Faculty of Public Health, Medical University, Sofia, Bulgaria
| | - Vladimir Petrov
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - Roman Pepovich
- Department of Infectious Pathology, Hygiene, Technology and Control of Foods from Animal Origin, Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria
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12
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Meester M, Tobias TJ, Bouwknegt M, Kusters NE, Stegeman JA, van der Poel WHM. Infection dynamics and persistence of hepatitis E virus on pig farms - a review. Porcine Health Manag 2021; 7:16. [PMID: 33546777 PMCID: PMC7863251 DOI: 10.1186/s40813-021-00189-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 01/01/2021] [Indexed: 12/16/2022] Open
Abstract
Background Hepatitis E virus (HEV) genotype 3 and 4 is a zoonosis that causes hepatitis in humans. Humans can become infected by consumption of pork or contact with pigs. Pigs are the main reservoir of the virus worldwide and the virus is present on most pig farms. Main body Though HEV is present on most farms, the proportion of infected pigs at slaughter and thus the level of exposure to consumers differs between farms and countries. Understanding the cause of that difference is necessary to install effective measures to lower HEV in pigs at slaughter. Here, HEV studies are reviewed that include infection dynamics of HEV in pigs and on farms, risk factors for HEV farm prevalence, and that describe mechanisms and sources that could generate persistence on farms. Most pigs become infected after maternal immunity has waned, at the end of the nursing or beginning of the fattening phase. Risk factors increasing the likelihood of a high farm prevalence or proportion of actively infected slaughter pigs comprise of factors such as farm demographics, internal and external biosecurity and immunomodulating coinfections. On-farm persistence of HEV is plausible, because of a high transmission rate and a constant influx of susceptible pigs. Environmental sources of HEV that enhance persistence are contaminated manure storages, water and fomites. Conclusion As HEV is persistently present on most pig farms, current risk mitigation should focus on lowering transmission within farms, especially between farm compartments. Yet, one should be aware of the paradox of increasing the proportion of actively infected pigs at slaughter by reducing transmission insufficiently. Vaccination of pigs may aid HEV control in the future.
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Affiliation(s)
- M Meester
- Farm Animal Health unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
| | - T J Tobias
- Farm Animal Health unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | | | - N E Kusters
- Wageningen Bioveterinary Research, Lelystad, the Netherlands
| | - J A Stegeman
- Farm Animal Health unit, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
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Surveillance Study of Hepatitis E Virus (HEV) in Domestic and Wild Ruminants in Northwestern Italy. Animals (Basel) 2020; 10:ani10122351. [PMID: 33317114 PMCID: PMC7764585 DOI: 10.3390/ani10122351] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/06/2020] [Accepted: 12/08/2020] [Indexed: 02/07/2023] Open
Abstract
Simple Summary Hepatitis E virus (HEV) infection can cause both acute and chronic hepatitis in humans and represents an emerging public health concern worldwide. In developed countries, zoonotic transmission of HEV genotypes 3 and 4 is caused by ingestion of raw or undercooked meat of infected swine or wild boars, the main reservoirs of HEV. However, in the last few years, molecular and serological evidence seem to indicate that several other animal species may act as HEV host, including domestic and wild ruminants. In this study, serum and fecal specimens from sheep, goats, red deer, roe deer, chamois, and Alpine ibex collected in two northwestern Italian regions (Piemonte and Valle d’Aosta) were screened molecularly and serologically. With the exception of chamois, HEV antibodies were found both in the domestic and wild ruminant species investigated with the highest rates in sheep and goats. These findings demonstrate that wild also domestic ruminants may be implicated in the viral cycle transmission. Abstract In industrialized countries, increasing autochthonous infections of hepatitis E virus (HEV) are caused by zoonotic transmission of genotypes (Gts) 3 and 4, mainly through consumption of contaminated raw or undercooked pork meat. Although swine and wild boar are recognized as the main reservoir for Gt3 and Gt4, accumulating evidence indicates that other animal species, including domestic and wild ruminants, may harbor HEV. Herein, we screened molecularly and serologically serum and fecal samples from two domestic and four wild ruminant species collected in Valle d’Aosta and Piemonte regions (northwestern Italy. HEV antibodies were found in sheep (21.6%), goats (11.4%), red deer (2.6%), roe deer (3.1%), and in Alpine ibex (6.3%). Molecular screening was performed using different primer sets targeting highly conserved regions of hepeviruses and HEV RNA, although at low viral loads, was detected in four fecal specimens (3.0%, 4/134) collected from two HEV seropositive sheep herds. Taken together, the data obtained document the circulation of HEV in the geographical area assessed both in wild and domestic ruminants, but with the highest seroprevalence in sheep and goats. Consistently with results from other studies conducted in southern Italy, circulation of HEV among small domestic ruminants seems to occur more frequently than expected.
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Tsachev I, Baymakova M, Pepovich R, Palova N, Marutsov P, Gospodinova K, Kundurzhiev T, Ciccozzi M. High Seroprevalence of Hepatitis E Virus Infection Among East Balkan Swine ( Sus scrofa) in Bulgaria: Preliminary Results. Pathogens 2020; 9:pathogens9110911. [PMID: 33153218 PMCID: PMC7693706 DOI: 10.3390/pathogens9110911] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 02/07/2023] Open
Abstract
The East Balkan swine (Sus scrofa) is the only aboriginal pig breed in Bulgaria, and it is indigenous to the eastern part of the country. The aim of the present study was to investigate East Balkan swine (EBS) in Bulgaria for serological evidence of hepatitis E virus (HEV). Sera from 171 swine from two parts of the country (northeastern and southeastern) were tested for anti-HEV IgG antibodies. The overall HEV seroprevalence was 82.5% (141/171), and for weaners it was 77.2% (44/57), for fattening pigs 79.0% (45/57), and for adults 91.2% (52/57). HEV positivity was higher in fattening pigs and adults compared to weaners: OR = 1.108 (95% CI: 0.456–2.692) and OR = 3.073 (95% CI: 1.016–9.294), respectively. This study provides the first evidence of exposure to HEV in EBS from Bulgaria.
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Affiliation(s)
- Ilia Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria; (I.T.); (P.M.); (K.G.)
| | - Magdalena Baymakova
- Department of Infectious Diseases, Military Medical Academy, 1606 Sofia, Bulgaria
- Correspondence: ; Tel.: +359-882-28-50-87
| | - Roman Pepovich
- Department of Infectious Pathology, Hygiene, Technology and Control of Foods from Animal Origin, Faculty of Veterinary Medicine, University of Forestry, 1797 Sofia, Bulgaria;
| | | | - Plamen Marutsov
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria; (I.T.); (P.M.); (K.G.)
| | - Krasimira Gospodinova
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria; (I.T.); (P.M.); (K.G.)
| | - Todor Kundurzhiev
- Department of Occupational Medicine, Faculty of Public Health, Medical University, 1527 Sofia, Bulgaria;
| | - Massimo Ciccozzi
- Unit of Medical Statistics and Molecular Epidemiology, Universita Campus Bio-Medico di Roma, 00128 Rome, Italy;
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Takova K, Koynarski T, Minkov I, Ivanova Z, Toneva V, Zahmanova G. Increasing Hepatitis E Virus Seroprevalence in Domestic Pigs and Wild Boar in Bulgaria. Animals (Basel) 2020; 10:ani10091521. [PMID: 32872096 PMCID: PMC7552291 DOI: 10.3390/ani10091521] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 12/16/2022] Open
Abstract
Simple Summary Hepatitis E virus (HEV) is a lesser-known hepatitis virus, but its worldwide spread is undisputed and has increased in recent years. The zoonotic spread of HEV, mainly due to genotype (gt) 3, emerged in developed countries in the past decade. In addition, transmission via contaminated meat from pigs and boars was also established. Detailed analysis of viral dynamics and distribution is needed in order to identify associated risk factors. The aim of the current study is to present new and additional data on the HEV distribution among pigs, and for the first-time, also among the wild boar population in Bulgaria. Abstract (1) Background: Hepatitis E virus (HEV) is a causative agent of acute viral hepatitis, predominantly transmitted by the fecal–oral route. In developed countries, HEV is considered to be an emerging pathogen since the number of autochthonous cases is rising. Hepatitis E is a viral disease with a proven zoonotic potential for some of its genotypes. The main viral reservoirs are domestic pigs and wild boar. Consumption of undercooked meat, as well as occupational exposure, are key factors for the spread of HEV. In order to evaluate the risks of future viral evolution, a detailed examination of the ecology and distribution of the virus is needed. The aim of the present study is to investigate the prevalence of anti-HEV IgG Ab in domestic pigs and wild boar in Bulgaria; (2) Methods: In this study, during the period of three years between 2017 and 2019, 433 serum samples from 19 different pig farms and 1 slaughterhouse were collected and analyzed. In addition, 32 samples from wild boar were also collected and analyzed during the 2018–2019 hunting season. All samples were analyzed by commercial indirect ELISA; (3) Results: Overall, HEV seroprevalence was 60% (95% CI 42.7–77.1) in domestic pigs and 12.5% (4/32) in wild boar. The observed seroprevalence of the slaughter-aged pigs was 73.65% (95% Cl 58.7–87.3). Prevalence in domestic pigs was significantly higher in the samples collected during 2019 (98% (95% Cl 96.1–99.9)) compared to those collected during 2017 (45.33% (95% CI 2.7–87.3)) and 2018 (38.46% (95% CI 29.1–49.7.); (4) Conclusions: Our findings suggest that domesticated pigs and wild boar might be the reason for the increased HEV transmission across Bulgaria. The genotypic characterization of HEV found in pigs, wild boar and humans will give a more accurate view of the zoonotic transmission of this virus.
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Affiliation(s)
- Katerina Takova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria; (K.T.); (V.T.)
| | - Tsvetoslav Koynarski
- Department of Animal Genetics, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria;
| | - Ivan Minkov
- Institute of Molecular Biology and Biotechnologies, 4000 Plovdiv, Bulgaria; (I.M.); (Z.I.)
- Center of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria
| | - Zdravka Ivanova
- Institute of Molecular Biology and Biotechnologies, 4000 Plovdiv, Bulgaria; (I.M.); (Z.I.)
| | - Valentina Toneva
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria; (K.T.); (V.T.)
- Institute of Molecular Biology and Biotechnologies, 4000 Plovdiv, Bulgaria; (I.M.); (Z.I.)
| | - Gergana Zahmanova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria; (K.T.); (V.T.)
- Center of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria
- Correspondence: ; Tel.: +359-32-261529
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