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Yamashita M, Iwamoto S, Ochiai M, Yamamoto A, Sudo K, Narushima R, Nagasaka T, Saito A, Oba M, Omatsu T, Mizutani T, Yamamoto K. Pathogenicity of genotype 2.1 classical swine fever virus isolated from Japan in 2019 in pigs. Microbiol Immunol 2024. [PMID: 38946035 DOI: 10.1111/1348-0421.13160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 05/13/2024] [Accepted: 06/09/2024] [Indexed: 07/02/2024]
Abstract
Classical swine fever (CSF) re-emerged in Japan in 2018 for the first time in 26 years. The disease has been known to be caused by a moderately pathogenic virus, rather than the highly pathogenic virus that had occurred in the past. However, the underlying pathophysiology remains unknown. This study conducted an experimental challenge on specific pathogen-free (SPF) pigs in a naïve state for 2, 4, and 6 weeks and confirmed the disease state during each period by clinical observation, virus detection, and pathological necropsy. We revealed the pathological changes and distribution of pathogens and virus-specific antibodies at each period after virus challenge. These results were comprehensively analyzed and approximately 70% of the pigs recovered, especially at 4- and 6-week post-virus challenge. This study provides useful information for future countermeasures against CSF by clarifying the pathogenicity outcomes in unvaccinated pigs with moderately pathogenic genotype 2.1 virus.
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Affiliation(s)
- Maiko Yamashita
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
- Center for Infectious Disease Epidemiology and Prevention Research, Tokyo University of Agriculture and Technology (Cooperative Division of Veterinary Sciences), Tokyo, Japan
| | - Shoko Iwamoto
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
| | - Mariko Ochiai
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
| | - Atsushi Yamamoto
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
| | - Kasumi Sudo
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
- Livestock Industry Bureau, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
| | - Rie Narushima
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
| | - Takao Nagasaka
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
| | - Akito Saito
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
- Exotic Diseases Research Station, National Institute of Animal Health, National Agriculture and Food Research Organization, Tokyo, Japan
| | - Mami Oba
- Center for Infectious Disease Epidemiology and Prevention Research, Tokyo University of Agriculture and Technology (Cooperative Division of Veterinary Sciences), Tokyo, Japan
| | - Tsutomu Omatsu
- Center for Infectious Disease Epidemiology and Prevention Research, Tokyo University of Agriculture and Technology (Cooperative Division of Veterinary Sciences), Tokyo, Japan
| | - Tetsuya Mizutani
- Center for Infectious Disease Epidemiology and Prevention Research, Tokyo University of Agriculture and Technology (Cooperative Division of Veterinary Sciences), Tokyo, Japan
| | - Kinya Yamamoto
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan
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Fonseca AA, Gonçalves VLDS, Barbosa AAS, Camargos MF. Use of FTA card for the detection of two RNA (CSFV and SV-A) and two DNA viruses (ASFVand SuHV-1) of importance in veterinary medicine. Braz J Microbiol 2024; 55:1961-1966. [PMID: 38589741 PMCID: PMC11153393 DOI: 10.1007/s42770-024-01309-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 03/11/2024] [Indexed: 04/10/2024] Open
Abstract
The FTA card has emerged as a promising alternative for nucleic acid extraction. The FTA card is a filter paper impregnated with chemicals that preserve and stabilize the genetic material present in the sample, allowing for its storage and transport at room temperature. The aim of this study was to test the card for the detection of RNA and DNA nucleic acids. Two RNA viruses (Senecavirus A and classical swine fever virus) and two DNA viruses (African swine fever virus and suid alphaherpesvirus 1) were tested, and in all cases, there was a decrease in sensitivity. The methods exhibited good repeatability and demonstrated a rapid and practical use for sample transport and nucleic acid extraction.
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Bohórquez JA, Muñoz-Aguilera A, Lanka S, Coronado L, Rosell R, Alberch M, Maddox CW, Ganges L. Development of a new loop-mediated isothermal amplification test for the sensitive, rapid, and economic detection of different genotypes of Classical swine fever virus. Front Cell Infect Microbiol 2024; 14:1372166. [PMID: 38686097 PMCID: PMC11056584 DOI: 10.3389/fcimb.2024.1372166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 04/01/2024] [Indexed: 05/02/2024] Open
Abstract
Background Classical swine fever virus (CSFV) remains one of the most important pathogens in animal health. Pathogen detection relies on viral RNA extraction followed by RT-qPCR. Novel technologies are required to improve diagnosis at the point of care. Methods A loop-mediated isothermal amplification (LAMP) PCR technique was developed, with primers designed considering all reported CSFV genotypes. The reaction was tested using both fluorometric and colorimetric detection, in comparison to the gold standard technique. Viral strains from three circulating CSFV genotypes were tested, as well as samples from infected animals. Other pathogens were also tested, to determine the LAMP specificity. Besides laboratory RNA extraction methods, a heating method for RNA release, readily available for adaptation to field conditions was evaluated. Results Three primer sets were generated, with one of them showing better performance. This primer set proved capable of maintaining optimal performance at a wide range of amplification temperatures (60°C - 68°C). It was also able to detect CSFV RNA from the three genotypes tested. The assay was highly efficient in detection of samples from animals infected with field strains from two different genotypes, with multiple matrices being detected using both colorimetric and fluorometric methods. The LAMP assay was negative for all the unrelated pathogens tested, including Pestiviruses. The only doubtful result in both fluorometric and colorimetric LAMP was against the novel Pestivirus italiaense, ovine Italy Pestivirus (OVPV), which has proven to have cross-reaction with multiple CSFV diagnostic techniques. However, it is only possible to detect the OVPV in a doubtful result if the viral load is higher than 10000 viral particles. Conclusion The results from the present study show that LAMP could be an important addition to the currently used molecular diagnostic techniques for CSFV. This technique could be used in remote locations, given that it can be adapted for successful use with minimal equipment and minimally invasive samples. The joined use of novel and traditional diagnostic techniques could prove to be a useful alternative to support the CSF control.
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Affiliation(s)
- Jose Alejandro Bohórquez
- Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Adriana Muñoz-Aguilera
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
- Unitat mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, Spain
- WOAH Collaborating Centre for the Research and Control of Emerging and Re-Emerging Swine Diseases in Europe (IRTA-CReSA), Barcelona, Spain
- Instituto Colombiano Agropecuario (ICA), Bogotá, DC, Colombia
| | - Saraswathi Lanka
- Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Liani Coronado
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
- Unitat mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, Spain
- WOAH Collaborating Centre for the Research and Control of Emerging and Re-Emerging Swine Diseases in Europe (IRTA-CReSA), Barcelona, Spain
| | - Rosa Rosell
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
- Unitat mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, Spain
- WOAH Collaborating Centre for the Research and Control of Emerging and Re-Emerging Swine Diseases in Europe (IRTA-CReSA), Barcelona, Spain
- Departament d’Acció Climàtica, Alimentació i Agenda Rural, Generalitat de Catalunya, Barcelona, Spain
| | - Mònica Alberch
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
- Unitat mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, Spain
- WOAH Collaborating Centre for the Research and Control of Emerging and Re-Emerging Swine Diseases in Europe (IRTA-CReSA), Barcelona, Spain
| | - Carol W. Maddox
- Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Llilianne Ganges
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
- Unitat mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Universitat Autònoma de Barcelona (UAB), Bellaterra, Barcelona, Spain
- WOAH Collaborating Centre for the Research and Control of Emerging and Re-Emerging Swine Diseases in Europe (IRTA-CReSA), Barcelona, Spain
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Robert E, Goonewardene K, El Kanoa I, Hochman O, Nfon C, Ambagala A. Oral Fluids for the Early Detection of Classical Swine Fever in Commercial Level Pig Pens. Viruses 2024; 16:318. [PMID: 38543685 PMCID: PMC10974009 DOI: 10.3390/v16030318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/15/2024] [Accepted: 02/17/2024] [Indexed: 05/23/2024] Open
Abstract
The early detection of classical swine fever (CSF) remains a key challenge, especially when outbreaks are caused by moderate and low-virulent CSF virus (CSFV) strains. Oral fluid is a reliable and cost-effective sample type that is regularly surveilled for endemic diseases in commercial pig herds in North America. Here, we explored the possibility of utilizing oral fluids for the early detection of CSFV incursions in commercial-size pig pens using two independent experiments. In the first experiment, a seeder pig infected with the moderately-virulent CSFV Pinillos strain was used, and in the second experiment, a seeder pig infected with the highly-virulent CSFV Koslov strain was used. Pen-based oral fluid samples were collected daily and individual samples (whole blood, swabs) every other day. All samples were tested by a CSFV-specific real-time RT-PCR assay. CSFV genomic material was detected in oral fluids on the seventh and fourth day post-introduction of the seeder pig into the pen, in the first and second experiments, respectively. In both experiments, oral fluids tested positive before the contact pigs developed viremia, and with no apparent sick pigs in the pen. These results indicate that pen-based oral fluids are a reliable and convenient sample type for the early detection of CSF, and therefore, can be used to supplement the ongoing CSF surveillance activities in North America.
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Affiliation(s)
- Erin Robert
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB R3E 0W2, Canada
| | - Kalhari Goonewardene
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Ian El Kanoa
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Orie Hochman
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Charles Nfon
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
| | - Aruna Ambagala
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3M4, Canada; (E.R.); (K.G.); (I.E.K.); (O.H.); (C.N.)
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB R3E 0W2, Canada
- Department of Animal Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
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Hinojosa Y, Liniger M, García-Nicolás O, Gerber M, Rajaratnam A, Muñoz-González S, Coronado L, Frías MT, Perera CL, Ganges L, Ruggli N. Evolutionary-Related High- and Low-Virulent Classical Swine Fever Virus Isolates Reveal Viral Determinants of Virulence. Viruses 2024; 16:147. [PMID: 38275957 PMCID: PMC10820463 DOI: 10.3390/v16010147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/13/2024] [Accepted: 01/15/2024] [Indexed: 01/27/2024] Open
Abstract
Classical swine fever (CSF) has been eradicated from Western and Central Europe but remains endemic in parts of Central and South America, Asia, and the Caribbean. CSF virus (CSFV) has been endemic in Cuba since 1993, most likely following an escape of the highly virulent Margarita/1958 strain. In recent years, chronic and persistent infections with low-virulent CSFV have been observed. Amino acid substitutions located in immunodominant epitopes of the envelope glycoprotein E2 of the attenuated isolates were attributed to positive selection due to suboptimal vaccination and control. To obtain a complete picture of the mutations involved in attenuation, we applied forward and reverse genetics using the evolutionary-related low-virulent CSFV/Pinar del Rio (CSF1058)/2010 (PdR) and highly virulent Margarita/1958 isolates. Sequence comparison of the two viruses recovered from experimental infections in pigs revealed 40 amino acid differences. Interestingly, the amino acid substitutions clustered in E2 and the NS5A and NS5B proteins. A long poly-uridine sequence was identified previously in the 3' untranslated region (UTR) of PdR. We constructed functional cDNA clones of the PdR and Margarita strains and generated eight recombinant viruses by introducing single or multiple gene fragments from Margarita into the PdR backbone. All chimeric viruses had comparable replication characteristics in porcine monocyte-derived macrophages. Recombinant PdR viruses carrying either E2 or NS5A/NS5B of Margarita, with 36 or 5 uridines in the 3'UTR, remained low virulent in 3-month-old pigs. The combination of these elements recovered the high-virulent Margarita phenotype. These results show that CSFV evolution towards attenuated variants in the field involved mutations in both structural and non-structural proteins and the UTRs, which act synergistically to determine virulence.
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Affiliation(s)
- Yoandry Hinojosa
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, 3012 Bern, Switzerland
- Centro Nacional de Sanidad Agropecuaria (CENSA), San José de las Lajas 32700, Cuba; (M.T.F.); (C.L.P.)
| | - Matthias Liniger
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Obdulio García-Nicolás
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Markus Gerber
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Anojen Rajaratnam
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Sara Muñoz-González
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (S.M.-G.); (L.C.); (L.G.)
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - Liani Coronado
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (S.M.-G.); (L.C.); (L.G.)
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - María Teresa Frías
- Centro Nacional de Sanidad Agropecuaria (CENSA), San José de las Lajas 32700, Cuba; (M.T.F.); (C.L.P.)
| | - Carmen Laura Perera
- Centro Nacional de Sanidad Agropecuaria (CENSA), San José de las Lajas 32700, Cuba; (M.T.F.); (C.L.P.)
| | - Llilianne Ganges
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (S.M.-G.); (L.C.); (L.G.)
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - Nicolas Ruggli
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
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Robert E, Goonewardene K, Lamboo L, Perez O, Goolia M, Lewis C, Erdelyan CNG, Lung O, Handel K, Moffat E, Embury-Hyatt C, Amaya NN, Parra CPC, Rueda DCG, Monroy MAR, Clavijo A, Ambagala A. Molecular and Pathological Characterization of Classical Swine Fever Virus Genotype 2 Strains Responsible for the 2013-2018 Outbreak in Colombia. Viruses 2023; 15:2308. [PMID: 38140549 PMCID: PMC10747092 DOI: 10.3390/v15122308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/07/2023] [Accepted: 11/16/2023] [Indexed: 12/24/2023] Open
Abstract
Classical swine fever (CSF) is a highly contagious transboundary viral disease of domestic and wild pigs. Despite mass vaccination and continuous eradication programs, CSF remains endemic in Asia, some countries in Europe, the Caribbean and South America. Since June 2013, Northern Colombia has reported 137 CSF outbreaks, mostly in backyard production systems with low vaccination coverage. The purpose of this study was to characterize the virus responsible for the outbreak. Phylogenetic analysis based on the full-length E2 sequence shows that the virus is closely related to CSF virus (CSFV) genotype 2.6 strains circulating in Southeast Asia. The pathotyping experiment suggests that the virus responsible is a moderately virulent strain. The 190 nucleotide stretch of the E2 hypervariable region of these isolates also shows high similarity to the CSFV isolates from Colombia in 2005 and 2006, suggesting a common origin for the CSF outbreaks caused by genotype 2.6 strains. The emergence of genotype 2.6 in Colombia suggests a potential transboundary spread of CSFV from Asia to the Americas, complicating the ongoing CSF eradication efforts in the Americas, and emphasizes the need for continuous surveillance in the region.
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Affiliation(s)
- Erin Robert
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Kalhari Goonewardene
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Lindsey Lamboo
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Orlando Perez
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Melissa Goolia
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Charles Lewis
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Cassidy N. G. Erdelyan
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Oliver Lung
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Katherine Handel
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Estella Moffat
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Carissa Embury-Hyatt
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Nancy Naranjo Amaya
- National Veterinary Laboratory, Instituto Colombiano Agropecurio, Bogota 110911, DC, Colombia; (N.N.A.); (C.P.C.P.); (D.C.G.R.); (M.A.R.M.)
| | - Claudia Patricia Calderón Parra
- National Veterinary Laboratory, Instituto Colombiano Agropecurio, Bogota 110911, DC, Colombia; (N.N.A.); (C.P.C.P.); (D.C.G.R.); (M.A.R.M.)
| | - Diana Cristina Gómez Rueda
- National Veterinary Laboratory, Instituto Colombiano Agropecurio, Bogota 110911, DC, Colombia; (N.N.A.); (C.P.C.P.); (D.C.G.R.); (M.A.R.M.)
| | - Maria Antonia Rincón Monroy
- National Veterinary Laboratory, Instituto Colombiano Agropecurio, Bogota 110911, DC, Colombia; (N.N.A.); (C.P.C.P.); (D.C.G.R.); (M.A.R.M.)
| | - Alfonso Clavijo
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
| | - Aruna Ambagala
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada; (E.R.); (K.G.); (L.L.); (O.P.); (M.G.); (C.L.); (C.N.G.E.); (O.L.); (K.H.); (E.M.); (C.E.-H.); (A.C.)
- Department of Animal Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
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Hu X, Feng S, Shi K, Shi Y, Yin Y, Long F, Wei X, Li Z. Development of a quadruplex real-time quantitative RT-PCR for detection and differentiation of PHEV, PRV, CSFV, and JEV. Front Vet Sci 2023; 10:1276505. [PMID: 38026635 PMCID: PMC10643766 DOI: 10.3389/fvets.2023.1276505] [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: 08/12/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023] Open
Abstract
Porcine hemagglutinating encephalomyelitis virus (PHEV), porcine pseudorabies virus (PRV), classical swine fever virus (CSFV), and Japanese encephalitis virus (JEV) cause similar neurological symptoms in the infected pigs, and their differential diagnosis depends on laboratory testing. Four pairs of specific primers and probes were designed targeting the PHEV N gene, PRV gB gene, CSFV 5' untranslated region (5'UTR), and JEV NS1 gene, respectively, and a quadruplex real-time quantitative RT-PCR (qRT-PCR) was developed to detect and differentiate PHEV, PRV, CSFV, and JEV. The assay showed high sensitivity, with the limit of detection (LOD) of 1.5 × 101 copies/μL for each pathogen. The assay specifically detected only PHEV, PRV, CSFV, and JEV, without cross-reaction with other swine viruses. The coefficients of variation (CVs) of the intra-assay and the inter-assay were less than 1.84%, with great repeatability. A total of 1,977 clinical samples, including tissue samples, and whole blood samples collected from Guangxi province in China, were tested by the developed quadruplex qRT-PCR, and the positivity rates of PHEV, PRV, CSFV, and JEV were 1.57% (31/1,977), 0.35% (7/1,977), 1.06% (21/1,977), and 0.10% (2/1,977), respectively. These 1,977 samples were also tested by the previously reported qRT-PCR assays, and the coincidence rates of these methods were more than 99.90%. The developed assay is demonstrated to be rapid, sensitive, and accurate for detection and differentiation of PHEV, PRV, CSFV, and JEV.
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Affiliation(s)
- Xin Hu
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Shuping Feng
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Kaichuang Shi
- College of Animal Science and Technology, Guangxi University, Nanning, China
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Yuwen Shi
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Yanwen Yin
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Feng Long
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Xiankai Wei
- Guangxi Center for Animal Disease Control and Prevention, Nanning, China
| | - Zongqiang Li
- College of Animal Science and Technology, Guangxi University, Nanning, China
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8
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Olesen AS, Lohse L, Johnston CM, Rasmussen TB, Bøtner A, Belsham GJ. Increased Presence of Circulating Cell-Free, Fragmented, Host DNA in Pigs Infected with Virulent African Swine Fever Virus. Viruses 2023; 15:2133. [PMID: 37896910 PMCID: PMC10612093 DOI: 10.3390/v15102133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 10/18/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
African swine fever virus (ASFV) causes severe hemorrhagic disease in domestic pigs and wild boar, often with high case fatality rates. The virus replicates in the circulating cells of the monocyte-macrophage lineage and within lymphoid tissues. The infection leads to high fever and a variety of clinical signs. In this study, it was observed that ASFV infection in pigs resulted in a >1000-fold increase in the level of circulating cell-free DNA (cfDNA), derived from the nuclei of host cells in the serum. This change occurred in parallel with the increase in circulating ASFV DNA. In addition, elevated levels (about 30-fold higher) of host mitochondrial DNA (mtDNA) were detected in the serum from ASFV-infected pigs. For comparison, the release of the cellular enzyme, lactate dehydrogenase (LDH), a commonly used marker of cellular damage, was also found to be elevated during ASFV infection, but later and less consistently. The sera from pigs infected with classical swine fever virus (CSFV), which causes a clinically similar disease to ASFV, were also tested but, surprisingly, this infection did not result in the release of cfDNA, mtDNA, or LDH. It was concluded that the level of cfDNA in the serum is a sensitive host marker of virulent ASFV infection.
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Affiliation(s)
- Ann Sofie Olesen
- Section for Veterinary Virology, Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen, Denmark; (L.L.); (C.M.J.); (T.B.R.)
| | - Louise Lohse
- Section for Veterinary Virology, Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen, Denmark; (L.L.); (C.M.J.); (T.B.R.)
| | - Camille Melissa Johnston
- Section for Veterinary Virology, Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen, Denmark; (L.L.); (C.M.J.); (T.B.R.)
| | - Thomas Bruun Rasmussen
- Section for Veterinary Virology, Department of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen, Denmark; (L.L.); (C.M.J.); (T.B.R.)
| | - Anette Bøtner
- Section for Veterinary Clinical Microbiology, Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, DK-1870 Frederiksberg, Denmark;
| | - Graham J. Belsham
- Section for Veterinary Clinical Microbiology, Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, DK-1870 Frederiksberg, Denmark;
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9
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Chen JY, Wu CM, Chia MY, Huang C, Chien MS. A prospective CSFV-PCV2 bivalent vaccine effectively protects against classical swine fever virus and porcine circovirus type 2 dual challenge and prevents horizontal transmission. Vet Res 2023; 54:57. [PMID: 37434231 DOI: 10.1186/s13567-023-01181-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/12/2023] [Indexed: 07/13/2023] Open
Abstract
Classical swine fever virus (CSFV) infection leading to CSF outbreaks is among the most devastating swine diseases in the pig industry. Porcine circovirus type 2 (PCV2) infection, resulting in porcine circovirus-associated disease (PCVAD), is also a highly contagious disease affecting pig health worldwide. To prevent and control disease occurrence, multiple-vaccine immunization is necessary in contaminated areas or countries. In this study, a novel CSFV-PCV2 bivalent vaccine was constructed and demonstrated to be capable of eliciting humoral and cellular immune responses against CSFV and PCV2, respectively. Moreover, a CSFV-PCV2 dual-challenge trial was conducted on specific-pathogen-free (SPF) pigs to evaluate vaccine efficacy. All of the vaccinated pigs survived and showed no clinical signs of infection throughout the experimental period. In contrast, placebo-vaccinated pigs exhibited severe clinical signs of infection and steeply increased viremia levels of CSFV and PCV2 after virus challenge. Additionally, neither clinical signs nor viral detections were noted in the sentinel pigs when cohabitated with vaccinated-challenged pigs at three days post-inoculation of CSFV, indicating that the CSFV-PCV2 bivalent vaccine completely prevents horizontal transmission of CSFV. Furthermore, conventional pigs were utilized to evaluate the application of the CSFV-PCV2 bivalent vaccine in field farms. An adequate CSFV antibody response and a significant decrease in PCV2 viral load in the peripheral lymph nodes were observed in immunized conventional pigs, suggesting its potential for clinical application. Overall, this study demonstrated that the CSFV-PCV2 bivalent vaccine effectively elicited protective immune responses and the ability to prevent horizontal transmission, which could be a prospective strategy for controlling both CSF and PCVAD in commercial herds.
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Affiliation(s)
- Jing-Yuan Chen
- Department of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, No. 1, Sec 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Chi-Ming Wu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan
| | - Min-Yuan Chia
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan
| | - Chienjin Huang
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan.
| | - Maw-Sheng Chien
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan.
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10
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Rossi A, Santi A, Barsi F, Casadei G, Di Donato A, Fontana MC, Galletti G, Garbarino CA, Lombardini A, Musto C, Prosperi A, Pupillo G, Rugna G, Tamba M. Eleven Years of Health Monitoring in Wild Boars ( Sus scrofa) in the Emilia-Romagna Region (Italy). Animals (Basel) 2023; 13:1832. [PMID: 37889705 PMCID: PMC10252029 DOI: 10.3390/ani13111832] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 05/26/2023] [Accepted: 05/30/2023] [Indexed: 10/29/2023] Open
Abstract
In recent years, the growth of wild ungulates has increased the focus on their health monitoring. In particular, the health status of wild boars is relevant for the economic impact on the pig industry. The Emilia-Romagna region activated a wildlife monitoring plan to better evaluate the health status of the wild boar population. Between 2011 and 2021, samples of found dead and hunted wild boar have been examined for trichinellosis, tuberculosis, brucellosis, african swine fever, classical swine fever, Aujeszky's disease, swine vesicular disease, and swine influenza A. Trichinella britovi was identified in 0.001% of the examined wild boars; neither M. bovis nor M. tuberculosis were found in M. tuberculosis complex positive samples; 2.3% were positive for Brucella suis; 29.4% of the sera were positive for Aujeszky's disease virus; and 0.9% of the samples were positive for swine influenza A virus. With an uncertain population estimate, the number of animals tested, the number of positives, and the sampling method do not allow us to make many inferences but suggest the need to implement and strengthen the existing surveillance activity, as it seems to be the only viable alternative for safeguarding animal and human health.
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Affiliation(s)
- Arianna Rossi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Annalisa Santi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Filippo Barsi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Gabriele Casadei
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Alessandra Di Donato
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Maria Cristina Fontana
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Giorgio Galletti
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Chiara Anna Garbarino
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Annalisa Lombardini
- Settore Prevenzione Collettiva e Sanità Pubblica, Direzione Generale Cura della Persona, Salute e Welfare, Emilia-Romagna Region, 40127 Bologna, Italy;
| | - Carmela Musto
- Department of Veterinary Medical Sciences, University of Bologna, 40064 Bologna, Italy;
| | - Alice Prosperi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Giovanni Pupillo
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Gianluca Rugna
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
| | - Marco Tamba
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia-Romagna “Bruno Ubertini”, 25124 Brescia, Italy (F.B.); (G.C.); (A.D.D.); (M.C.F.); (G.G.); (C.A.G.); (A.P.); (G.P.); (G.R.); (M.T.)
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11
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First Report of Swinepox in a Wild Boar in Italy: Pathologic and Molecular Findings. Pathogens 2023; 12:pathogens12030472. [PMID: 36986394 PMCID: PMC10056785 DOI: 10.3390/pathogens12030472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 03/19/2023] Open
Abstract
Swinepox virus (SWPV) is responsible for sporadic acute poxvirus infections in swine worldwide, causing a pathognomonic eruptive proliferative dermatitis. Beside direct and congenital transmission, the pig louse Haematopinus suis acts as a mechanical vector and favors virus infection through skin lesions. Infections are generally described in domestic pigs, while only a few cases have been reported in wild boars, in Austria and Germany. In September 2022, SWPV infection was suspected at post-mortem examination of a wild boar piglet with characteristic lesions in Liguria, Northwest Italy. The piglet was heavily parasitized by swine lice (H. suis). SWPV was then confirmed by histological and molecular analyses. Possible viral co-infections were also investigated (African swine fever virus, classical swine fever virus, parvovirus, circovirus, Aujeszky’s disease virus and hepatitis E virus). This article describes gross and histopathologic features of SWPV infection, differential diagnosis, and potential vector-borne transmission to domestic pigs, presenting a brief review of the literature on the topic. SWPV infection is reported in wild boars in Italy for the first time. The finding of SWPV in a wild boar in an area with a very limited pig population may suggest the existence of a “wildlife cycle” in the area. Further investigations are needed to understand the real risk of transmission of SWPV to domestic pigs as well as the role of other arthropod vectors.
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12
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Acosta A, Dietze K, Baquero O, Osowski GV, Imbacuan C, Burbano A, Ferreira F, Depner K. Risk Factors and Spatiotemporal Analysis of Classical Swine Fever in Ecuador. Viruses 2023; 15:288. [PMID: 36851503 PMCID: PMC9966056 DOI: 10.3390/v15020288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/10/2023] [Accepted: 01/15/2023] [Indexed: 01/21/2023] Open
Abstract
Classical swine fever (CSF) is one of the most important re-emergent swine diseases worldwide. Despite concerted control efforts in the Andean countries, the disease remains endemic in several areas, limiting production and trade opportunities. In this study, we aimed to determine the risk factors and spatiotemporal implications associated with CSF in Ecuador. We analysed passive surveillance and vaccination campaign datasets from 2014 to 2020; Then, we structured a herd-level case-control study using a logistic and spatiotemporal Bayesian model. The results showed that the risk factors that increased the odds of CSF occurrence were the following: swill feeding (OR 8.53), time until notification (OR 2.44), introduction of new pigs during last month (OR 2.01) and lack of vaccination against CSF (OR 1.82). The spatiotemporal model showed that vaccination reduces the risk by 33%. According to the priority index, the intervention should focus on Morona Santiago and Los Rios provinces. In conclusion, the results highlight the complexity of the CSF control programs, the importance to improve the overall surveillance system and the need to inform decision-makers and stakeholders.
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Affiliation(s)
- Alfredo Acosta
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, 17493 Greifswald, Germany
- Laboratory of Epidemiology and Biostatistics, School of Veterinary Medicine and Animal Science, Preventive Veterinary Medicine Department, University of São Paulo, São Paulo 05508-270, Brazil
| | - Klaas Dietze
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, 17493 Greifswald, Germany
| | - Oswaldo Baquero
- Laboratory of Epidemiology and Biostatistics, School of Veterinary Medicine and Animal Science, Preventive Veterinary Medicine Department, University of São Paulo, São Paulo 05508-270, Brazil
| | - Germana Vizzotto Osowski
- Laboratory of Epidemiology and Biostatistics, School of Veterinary Medicine and Animal Science, Preventive Veterinary Medicine Department, University of São Paulo, São Paulo 05508-270, Brazil
| | - Christian Imbacuan
- General Coordination of Animal Health, Phyto-Zoosanitary Regulation and Control Agency, Quito 170903, Ecuador
| | - Alexandra Burbano
- General Coordination of Animal Health, Phyto-Zoosanitary Regulation and Control Agency, Quito 170903, Ecuador
| | - Fernando Ferreira
- Laboratory of Epidemiology and Biostatistics, School of Veterinary Medicine and Animal Science, Preventive Veterinary Medicine Department, University of São Paulo, São Paulo 05508-270, Brazil
| | - Klaus Depner
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, 17493 Greifswald, Germany
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13
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Bohórquez JA, Wang M, Díaz I, Alberch M, Pérez-Simó M, Rosell R, Gladue DP, Borca MV, Ganges L. The FlagT4G Vaccine Confers a Strong and Regulated Immunity and Early Virological Protection against Classical Swine Fever. Viruses 2022; 14:v14091954. [PMID: 36146761 PMCID: PMC9502879 DOI: 10.3390/v14091954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/30/2022] [Accepted: 08/30/2022] [Indexed: 11/20/2022] Open
Abstract
Control of classical swine fever virus (CSFV) in endemic countries relies on vaccination, mostly using vaccines that do not allow for differentiation of vaccinated from infected animals (DIVA). FlagT4G vaccine is a novel candidate that confers robust immunity and shows DIVA capabilities. The present study assessed the immune response elicited by FlagT4G and its capacity to protect pigs for a short time after vaccination. Five days after a single dose of FlagT4G vaccine, animals were challenged with a highly virulent CSFV strain. A strong, but regulated, interferon-α response was found after vaccination. Vaccinated animals showed clinical and virological protection against the challenge, in the absence of antibody response at 5 days post-vaccination. Upon challenge, a rapid rise in the titers of CSFV neutralizing antibodies and an increase in the IFN-γ producing cells were noticed in all vaccinated-challenged pigs. Meanwhile, unvaccinated pigs showed severe clinical signs and high viral replication, being euthanized before the end of the trial. These animals were unable to generate neutralizing antibodies and IFN-γ responses after the CSFV challenge. The results from the present study assert the fast and efficient protection by FlagT4G, a highly promising tool for CSFV control worldwide.
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Affiliation(s)
- José Alejandro Bohórquez
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61820, USA
| | - Miaomiao Wang
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Ivan Díaz
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Mònica Alberch
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Marta Pérez-Simó
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Rosa Rosell
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- Departament d’Acció Climàtica, Alimentació i Agenda Rural, Generalitat de Catalunya, 08007 Barcelona, Spain
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.); (L.G.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.); (L.G.)
| | - Llilianne Ganges
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- Correspondence: (D.P.G.); (M.V.B.); (L.G.)
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14
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Annaheim D, Vogler BR, Sigrist B, Vögtlin A, Hüssy D, Breitler C, Hartnack S, Grund C, King J, Wolfrum N, Albini S. Screening of Healthy Feral Pigeons (Columba livia domestica) in the City of Zurich Reveals Continuous Circulation of Pigeon Paramyxovirus-1 and a Serious Threat of Transmission to Domestic Poultry. Microorganisms 2022; 10:microorganisms10081656. [PMID: 36014074 PMCID: PMC9412584 DOI: 10.3390/microorganisms10081656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/16/2022] Open
Abstract
Pigeon paramyxovirus-1 (PPMV-1) is predominantly isolated from pigeons or doves and forms a separate group of viral strains within Avian Orthoavulavirus-1, the causative agent of Newcastle disease in poultry. Since the introduction of PPMV-1 into Europe in 1981, these strains have rapidly spread all over Europe, and are nowadays considered to be enzootic in feral and hobby pigeons (Columba livia domestica). Infections with PPMV-1 can range from asymptomatic to fatal. To assess whether PPMV-1 continuously circulates in healthy feral pigeons, 396 tissue samples of pigeons from the city of Zurich were tested by reverse transcriptase real-time PCR over the period of one year. PPMV-1-RNA was detected in 41 feral pigeons (10.35%), determined as the dominant European genotype VI.2.1.1.2.2. In 38 of the 41 pigeons where organ samples tested positive, PPMV-1-RNA was also detected in either choana or cloaca swabs. There were no significant differences in positivity rates between seasons, age, and sex. The current study shows that feral pigeons without clinical signs of disease can harbour and most likely excrete PPMV-1. Spill-over into free-range holdings of chickens are therefore possible, as observed in a recent outbreak of Newcastle disease in laying hens due to PPMV-1 genotype VI.2.1.1.2.2. in the canton of Zurich in January 2022.
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Affiliation(s)
- Désirée Annaheim
- National Reference Center for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Barbara Renate Vogler
- National Reference Center for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Brigitte Sigrist
- National Reference Center for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Andrea Vögtlin
- Institute of Virology and Immunology (IVI), 3147 Mittelhäusern, Switzerland
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
| | - Daniela Hüssy
- Institute of Virology and Immunology (IVI), 3147 Mittelhäusern, Switzerland
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
| | | | - Sonja Hartnack
- Section of Epidemiology, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Christian Grund
- Institute of Diagnostic Virology, Friedrich Loeffler-Institut, 17493 Greifswald, Germany
| | - Jacqueline King
- Institute of Diagnostic Virology, Friedrich Loeffler-Institut, 17493 Greifswald, Germany
| | - Nina Wolfrum
- National Reference Center for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
- Correspondence: (N.W.); (S.A.)
| | - Sarah Albini
- National Reference Center for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
- Correspondence: (N.W.); (S.A.)
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15
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Chen N, Wang Q, Hu Y, Sun Y, Li J, Wu H, Xu L, Liu H, Yang C, Chen X, Deng Y, Xia Y, Zhang Q, Cheng S, Fan A, Chen G. Comparative efficacy evaluation of different CSF vaccines in pigs with CSF maternally derived antibodies. Vet Microbiol 2022; 273:109541. [PMID: 36027683 DOI: 10.1016/j.vetmic.2022.109541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 08/01/2022] [Accepted: 08/07/2022] [Indexed: 11/18/2022]
Abstract
Classical swine fever (CSF) is a highly contagious and important swine disease in China. Sporadic outbreaks with mild clinical signs are still being reported despite massive vaccination with the CSF C-strain vaccine. One possible reason for vaccine failure could be interference from maternally derived antibodies (MDAs) during vaccination in the field. The aim of this study was to evaluate the efficacy of different CSF vaccines in the presence of MDAs and to assess the different vaccination schemes in the field. The results demonstrated that vaccination with a single dose of C-strain-PK vaccine protected pigs against severe clinical signs and significantly reduced viremia. The impact of MDAs was negligible. The interference was also mild during a prime and boost vaccination scheme using the C-strain-ST vaccine. In contrast, a significant influence of MDAs on the efficacy of the subunit E2 vaccine in a one-dose vaccination scheme was observed, with pigs showing severe clinical signs, CSF-associated death, typical pathological lesions and a high level of viremia after challenge, despite robust E2 antibody induction. A field vaccination and challenge study further confirmed the superior effectiveness of a single dose of C-strain-PK vaccine in the presence of MDAs in comparison to a routine prime and boost vaccination scheme applied in the field, with pigs having fever, chronic signs, significant viremia and shedding after challenge. Delaying the vaccination time from the age of 28 days to 45 days, when MDA was low, was beneficial for improving the clinical protection and immunity induced by vaccines. Altogether, the results presented here emphasize that a high-quality vaccine and a scientific design of the vaccination scheme based on serological surveillance are essential pillars to control and eliminate CSF in China.
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Affiliation(s)
- Ning Chen
- Boehringer Ingelheim Vetmedica (China) Co. Ltd., Taizhou 225300, People's Republic of China.
| | - Qin Wang
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Yulong Hu
- Boehringer Ingelheim Animal Health (Shanghai) Co. Ltd., Shanghai 200040, People's Republic of China
| | - Yanyong Sun
- Boehringer Ingelheim Vetmedica (China) Co. Ltd., Taizhou 225300, People's Republic of China
| | - Junping Li
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Huawei Wu
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Lu Xu
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Huanhuan Liu
- Boehringer Ingelheim Vetmedica (China) Co. Ltd., Taizhou 225300, People's Republic of China
| | - Chenghuai Yang
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Xiaochun Chen
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Yong Deng
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Yingju Xia
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Qianyi Zhang
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Shi Cheng
- Boehringer Ingelheim Animal Health (Shanghai) Co. Ltd., Shanghai 200040, People's Republic of China
| | - Aihua Fan
- Boehringer Ingelheim Animal Health (Shanghai) Co. Ltd., Shanghai 200040, People's Republic of China
| | - Guanghua Chen
- World Organisation for Animal Health, Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China.
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16
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Removal of the E rns RNase Activity and of the 3' Untranslated Region Polyuridine Insertion in a Low-Virulence Classical Swine Fever Virus Triggers a Cytokine Storm and Lethal Disease. J Virol 2022; 96:e0043822. [PMID: 35758667 PMCID: PMC9327722 DOI: 10.1128/jvi.00438-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In this study, we assessed the potential synergistic effect of the Erns RNase activity and the poly-U insertion in the 3′ untranslated region (UTR) of the low-virulence classical swine fever virus (CSFV) isolate Pinar de Rio (PdR) in innate and adaptive immunity regulation and its relationship with classical swine fever (CSF) pathogenesis in pigs. We knocked out the Erns RNase activity of PdR and replaced the long polyuridine sequence of the 3′ UTR with 5 uridines found typically at this position, resulting in a double mutant, vPdR-H30K-5U. This mutant induced severe CSF in 5-day-old piglets and 3-week-old pigs, with higher lethality in the newborn (89.5%) than in the older (33.3%) pigs. However, the viremia and viral excretion were surprisingly low, while the virus load was high in the tonsils. Only alpha interferon (IFN-α) and interleukin 12 (IL-12) were highly and consistently elevated in the two groups. Additionally, high IL-8 levels were found in the newborn but not in the older pigs. This points toward a role of these cytokines in the CSF outcome, with age-related differences. The disproportional activation of innate immunity might limit systemic viral spread from the tonsils and increase virus clearance, inducing strong cytokine-mediated symptoms. Infection with vPdR-H30K-5U resulted in poor neutralizing antibody responses compared with results obtained previously with the parent and RNase knockout PdR. This study shows for the first time the synergistic effect of the 3′ UTR and the Erns RNase function in regulating innate immunity against CSFV, favoring virus replication in target tissue and thus contributing to disease severity. IMPORTANCE CSF is one of the most relevant viral epizootic diseases of swine, with high economic and sanitary impact. Systematic stamping out of infected herds with and without vaccination has permitted regional virus eradication. However, the causative agent, CSFV, persists in certain areas of the world, leading to disease reemergence. Nowadays, low- and moderate-virulence strains that could induce unapparent CSF forms are prevalent, posing a challenge for disease eradication. Here, we show for the first time the synergistic role of lacking the Erns RNase activity and the 3′ UTR polyuridine insertion from a low-virulence CSFV isolate in innate immunity disproportional activation. This might limit systemic viral spread to the tonsils and increase virus clearance, inducing strong cytokine-mediated symptoms, thus contributing to disease severity. These results highlight the role played by the Erns RNase activity and the 3′ UTR in CSFV pathogenesis, providing new perspectives for novel diagnostic tools and vaccine strategies.
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17
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Pendl H, Hernández-Lara C, Kubacki J, Borel N, Albini S, Valkiūnas G. Exo-erythrocytic development of Plasmodium matutinum (lineage pLINN1) in a naturally infected roadkill fieldfare Turdus pilaris. Malar J 2022; 21:148. [PMID: 35570274 PMCID: PMC9107739 DOI: 10.1186/s12936-022-04166-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/20/2022] [Indexed: 11/30/2022] Open
Abstract
Background Species of Plasmodium (Haemosporida, Plasmodiidae) are remarkably diverse haemoparasites. Information on genetic diversity of avian malaria pathogens has been accumulating rapidly, however exo-erythrocytic development of these organisms remains insufficiently addressed. This is unfortunate because, contrary to Plasmodium species parasitizing mammals, the avian malaria parasites undergo several cycles of exo-erythrocytic development, often resulting in damage of various organs. Insufficient knowledge on the exo-erythrocytic development in most described Plasmodium species precludes the understanding of mechanisms of virulence during avian malaria. This study extends information on the exo-erythrocytic development of bird malaria parasites. Methods A roadkill fieldfare (Turdus pilaris) was sampled in Switzerland and examined using pathologic, cytologic, histologic, molecular and microbiologic methods. Avian malaria was diagnosed, and erythrocytic and exo-erythrocytic stages of the parasite were identified using morphologic characteristics and barcode DNA sequences of the cytochrome b gene. The species-specific characteristics were described, illustrated, and pathologic changes were reported. Results An infection with Plasmodium matutinum lineage pLINN1 was detected. Parasitaemia was relatively low (0.3%), with all erythrocytic stages (trophozoites, meronts and gametocytes) present in blood films. Most growing erythrocytic meronts were markedly vacuolated, which is a species-specific feature of this parasite’s development. Phanerozoites at different stages of maturation were seen in leukocytes, macrophages, and capillary endothelial cells in most organs examined; they were particularly numerous in the brain. Like the erythrocytic meronts, growing phanerozoites were markedly vacuolated. Conspicuous exo-erythrocytic development and maturation in leucocytes suggests that this fieldfare was not adapted to the infection and the parasite was capable to escape from cellular immunity. Conclusions This is the first report of exo-erythrocytic development of the malaria parasite lineage pLINN1 during single infection and the first report of this lineage in the fieldfare. The findings of multiple phanerozoites in brain, skeletal muscle, and eye tissue in combination with signs of vascular blockage and thrombus formation strongly suggest an impaired vision and neuromuscular responsiveness as cause of the unexpected collision with a slowly moving car. Further studies on exo-erythrocytic stages of haemosporidian parasites are pivotal to understand the true level of populational damage of avian malaria in wild birds.
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18
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Phylodynamics of classical swine fever virus in Brazil. Braz J Microbiol 2022; 53:1065-1075. [PMID: 35394611 PMCID: PMC9151941 DOI: 10.1007/s42770-022-00724-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 02/23/2022] [Indexed: 02/01/2023] Open
Abstract
The classical swine fever virus is the etiologic agent of one of the diseases with the greatest impact on swine farming worldwide. An extensive area of Brazil is considered free of the disease, but some states in Northeast Brazil have registered outbreaks since 2001. The objective of this study was to analyze the genetic variations of the virus and its spread over time and space. Partial sequences of the viral E2 protein obtained from samples collected during the Brazilian outbreaks were compared with sequences from the GenBank database (NCBI). The results demonstrated the continuous presence of the virus in the state of Ceará, with diffusion to at least two other states. The Brazilian Northeast virus presents specific polymorphisms that separate it from viruses isolated in other countries.
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19
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Establishment of a Direct PCR Assay for Simultaneous Differential Diagnosis of African Swine Fever and Classical Swine Fever Using Crude Tissue Samples. Viruses 2022; 14:v14030498. [PMID: 35336904 PMCID: PMC8948687 DOI: 10.3390/v14030498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/17/2022] [Accepted: 02/25/2022] [Indexed: 12/04/2022] Open
Abstract
African swine fever (ASF) and classical swine fever (CSF) are contagious swine diseases that are clinically indistinguishable from each other; hence, reliable test methods for accurate diagnosis and differentiation are highly demanded. By employing a buffer system suitable for crude extraction of nucleic acids together with an impurity-tolerant enzyme, we established a multiplex assay of real-time reverse-transcription polymerase chain reaction (rRT-PCR) for simultaneous detection of ASF virus (ASFV), CSF virus (CSFV) and swine internal control derived genes in a sample without the need for prior purification of viral nucleic acids. We applied this method to test serum and tissue samples of infected pigs and wild boars and compared the statistical sensitivities and specificities with those of standard molecular diagnostic methods. When a serum was used as a test material, the newly established assay showed 94.4% sensitivity for both and 97.9 and 91.9% specificity for ASFV and CSFV detection, respectively. In contrast, the results were 100% identical with those obtained by the standard methods when a crude tissue homogenate was used as a test material. The present data indicate that this new assay offers a practical, quick, and reliable technique for differential diagnosis of ASF and CSF where geographical occurrences are increasingly overlapping.
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20
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Development of a one-step multiplex qRT–PCR assay for the detection of African swine fever virus, classical swine fever virus and atypical porcine pestivirus. BMC Vet Res 2022; 18:43. [PMID: 35042532 PMCID: PMC8764768 DOI: 10.1186/s12917-022-03144-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 01/06/2022] [Indexed: 12/02/2022] Open
Abstract
Background African swine fever virus (ASFV), classical swine fever virus (CSFV) and atypical porcine pestivirus (APPV) have caused great economic losses to the swine industry in China. Since coinfections of ASFV, CSFV and APPV occur in certain pig herds, it is necessary to accurately and differentially detect these pathogens in field-collected samples. In this study, a one-step multiplex real-time quantitative reverse transcription-polymerase chain reaction (multiplex qRT–PCR) was developed for the simultaneous and differential detection of ASFV, CSFV and APPV. Results The one-step multiplex qRT–PCR presented here was able to simultaneously detect ASFV, CSFV and APPV but could not amplify other viruses, including porcine circovirus type 2 (PCV2), pseudorabies virus (PRV), porcine reproductive and respiratory syndrome virus (PRRSV), foot-and-mouth disease virus (FMDV), porcine parvovirus (PPV), porcine epidemic diarrhoea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine rotavirus (PRoV), porcine deltacoronavirus (PDCoV), border disease virus (BDV), bovine viral diarrhoea virus type 1 (BVDV-1), BVDV-2, etc. The limit of detection (LOD) of the assay was 2.52 × 101 copies/μL for ASFV, CSFV and APPV. A repeatability test using standard recombinant plasmids showed that the intra- and interassay coefficients of variation (CVs) were less than 2%. An assay of 509 clinical samples collected in Guangxi Province, southern China, from October 2018 to December 2020 showed that the positive rates of ASFV, CSFV and APPV were 45.58, 12.57 and 3.54%, respectively, while the coinfection rates of ASFV and CSFV, ASFV and APPV, CSFV and APPV were 4.91, 1.38, 0.98%, respectively. Phylogenetic analysis based on the nucleotide sequences of the partial ASFV p72 gene showed that all ASFV strains from Guangxi Province belonged to genotypes I and II. Conclusion A one-step multiplex qRT–PCR with high specificity, sensitivity and repeatability was successfully developed for the simultaneous and differential detection of ASFV, CSFV and APPV.
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21
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Stalder S, Marti H, Borel N, Vogler BR, Pesch T, Prähauser B, Wencel P, Laroucau K, Albini S. Falcons From the United Arab Emirates Infected With Chlamydia psittaci/ C abortus Intermediates Specified as Chlamydia buteonis by Polymerase Chain Reaction. J Avian Med Surg 2021; 35:333-340. [PMID: 34677032 DOI: 10.1647/20-00050] [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: 11/11/2022]
Abstract
Chlamydiaceae are obligate intracellular bacteria with a broad host range. Several studies have found chlamydial species that are genetically intermediate between Chlamydia psittaci and Chlamydia abortus in various avian species. One of these intermediate Chlamydia species, found in a red-shouldered hawk (Buteo lineatus), was recently classified as a new species Chlamydia buteonis. This newly described Chlamydia species has, so far, only been reported in hawks exhibiting clinical signs of conjunctivitis, dyspnea, and diarrhea. In the present study, fecal samples of 5 gyrfalcons (Falco rusticolus), 3 gyr/peregrine falcon hybrids (Falco rusticolus × Falco peregrinus), and 15 falcons of unknown species presented to falcon clinics on the Arabian Peninsula were shipped to the Vetsuisse Faculty, University of Zurich (Zurich, Switzerland), for examination for the presence of Chlamydiaceae. A step-wise diagnostic approach was performed to identify the chlamydial species involved. Chlamydiaceae were detected in 21/23 falcons by a family-specific real-time quantitative PCR (qPCR). Further identification with a 23S ribosomal RNA-based microarray assay and 16S conventional PCR and sequencing yielded inconclusive results, indicating the presence of an intermediate Chlamydia species. Because none of the falcons tested positive for Chlamydia psittaci by specific qPCR, all 23 samples were subjected to a Chlamydia buteonis-specific qPCR, which was positive in 16/23 samples. Detailed information regarding clinical history was available for 8 falcons admitted to a falcon clinic in Dubai, United Arab Emirates. Six of those birds that were presented to the clinic because of loss of performance and poor general condition, including vomiting and diarrhea, were positive for C buteonis. In 2 birds without clinical disease signs admitted for a routine health examination, 1 was positive for C buteonis, and 1 was negative. It is yet unknown whether Chlamydia buteonis causes disease in birds, but the findings in this study indicate that Chlamydia buteonis may be an infectious pathogen in falcon species.
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Affiliation(s)
- Sandro Stalder
- National Reference Center for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland,
| | - Hanna Marti
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Nicole Borel
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Barbara Renate Vogler
- National Reference Center for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Theresa Pesch
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Barbara Prähauser
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Peter Wencel
- Al Aseefa Falcon Hospital, Nad Al Sheba, Dubai, United Arab Emirates
| | - Karine Laroucau
- Bacterial Zoonoses Unit, Animal Health Laboratory, University Paris-Est, Anses, 94706 Maisons-Alfort Cedex, France
| | - Sarah Albini
- National Reference Center for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
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22
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Activation of Dendritic Cells in Tonsils Is Associated with CD8 T Cell Responses following Vaccination with Live Attenuated Classical Swine Fever Virus. Int J Mol Sci 2021; 22:ijms22168795. [PMID: 34445493 PMCID: PMC8395915 DOI: 10.3390/ijms22168795] [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: 05/15/2021] [Revised: 07/28/2021] [Accepted: 08/06/2021] [Indexed: 11/20/2022] Open
Abstract
Classical swine fever (CSF) is a highly contagious disease caused by the classical swine fever virus (CSFV). The live attenuated C-strain vaccine is highly efficacious, initiating protection within several days of delivery. The vaccine strain is detected in the tonsil early after inoculation, yet little is known of the role that tonsillar immune cells might play in initiating protection. Comparing the C-strain vaccine with the pathogenic CSFV Alfort-187 strain, changes in the myeloid cell compartment of the tonsil were observed. CSFV infection led to the emergence of an additional CD163+CD14+ cell population, which showed the highest levels of Alfort-187 and C-strain infection. There was also an increase in both the frequency and activation status (as shown by increased MHC-II expression) of the tonsillar conventional dendritic cells 1 (cDC1) in pigs inoculated with the C-strain. Notably, the activation of cDC1 cells coincided in time with the induction of a local CSFV-specific IFN-γ+ CD8 T cell response in C-strain vaccinated pigs, but not in pigs that received Alfort-187. Moreover, the frequency of CSFV-specific IFN-γ+ CD8 T cells was inversely correlated to the viral load in the tonsils of individual animals. Accordingly, we hypothesise that the activation of cDC1 is key in initiating local CSFV-specific CD8 T cell responses which curtail early virus replication and dissemination.
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Wang M, Bohórquez JA, Hinojosa Y, Muñoz-González S, Gerber M, Coronado L, Perera CL, Liniger M, Ruggli N, Ganges L. Abrogation of the RNase activity of E rns in a low virulence classical swine fever virus enhances the humoral immune response and reduces virulence, transmissibility, and persistence in pigs. Virulence 2021; 12:2037-2049. [PMID: 34339338 PMCID: PMC8331007 DOI: 10.1080/21505594.2021.1959715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The prevalence of low virulence classical swine fever virus (CSFV) strains makes viral eradication difficult in endemic countries. However, the determinants for natural CSFV attenuation and persistence in the field remain unidentified. The aim of the present study was to assess the role of the RNase activity of CSFV Erns in pathogenesis, immune response, persistent infection, and viral transmission in pigs. To this end, a functional cDNA clone pPdR-H30K-36U with an Erns lacking RNase activity was constructed based on the low virulence CSFV field isolate Pinar de Rio (PdR). Eighteen 5-day-old piglets were infected with vPdR-H30K-36U. Nine piglets were introduced as contacts. The vPdR-H30K-36U virus was attenuated in piglets compared to the parental vPdR-36U. Only RNA traces were detected in sera and body secretions and no virus was isolated from tonsils, showing that RNase inactivation may reduce CSFV persistence and transmissibility. The vPdR-H30K-36U mutant strongly activated the interferon-α (IFN-α) production in plasmacytoid dendritic cells, while in vivo, the IFN-α response was variable, from moderate to undetectable depending on the animal. This suggests a role of the CSFV Erns RNase activity in the regulation of innate immune responses. Infection with vPdR-H30K-36U resulted in higher antibody levels against the E2 and Erns glycoproteins and in enhanced neutralizing antibody responses when compared with vPdR-36U. These results pave the way toward a better understanding of viral attenuation mechanisms of CSFV in pigs. In addition, they provide novel insights relevant for the development of DIVA vaccines in combination with diagnostic assays for efficient CSF control.
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Affiliation(s)
- Miaomiao Wang
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
| | | | - Yoandry Hinojosa
- Division of Virology, Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology (DIP), Vetsuisse Faculty, University of Bern, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Bern, Switzerland.,Centro Nacional De Sanidad Agropecuaria (CENSA), Mayabeque, Cuba
| | - Sara Muñoz-González
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
| | - Markus Gerber
- Division of Virology, Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology (DIP), Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Liani Coronado
- Centro Nacional De Sanidad Agropecuaria (CENSA), Mayabeque, Cuba
| | | | - Matthias Liniger
- Division of Virology, Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology (DIP), Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Nicolas Ruggli
- Division of Virology, Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology (DIP), Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
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Proline to Threonine Mutation at Position 162 of NS5B of Classical Swine Fever Virus Vaccine C Strain Promoted Genome Replication and Infectious Virus Production by Facilitating Initiation of RNA Synthesis. Viruses 2021; 13:v13081523. [PMID: 34452387 PMCID: PMC8402891 DOI: 10.3390/v13081523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 12/11/2022] Open
Abstract
The 3′untranslated region (3′UTR) and NS5B of classical swine fever virus (CSFV) play vital roles in viral genome replication. In this study, two chimeric viruses, vC/SM3′UTR and vC/b3′UTR, with 3′UTR substitution of CSFV Shimen strain or bovine viral diarrhea virus (BVDV) NADL strain, were constructed based on the infectious cDNA clone of CSFV vaccine C strain, respectively. After virus rescue, each recombinant chimeric virus was subjected to continuous passages in PK-15 cells. The representative passaged viruses were characterized and sequenced. Serial passages resulted in generation of mutations and the passaged viruses exhibited significantly increased genomic replication efficiency and infectious virus production compared to parent viruses. A proline to threonine mutation at position 162 of NS5B was identified in both passaged vC/SM3′UTR and vC/b3′UTR. We generated P162T mutants of two chimeras using the reverse genetics system, separately. The single P162T mutation in NS5B of vC/SM3′UTR or vC/b3′UTR played a key role in increased viral genome replication and infectious virus production. The P162T mutation increased vC/SM3′UTRP162T replication in rabbits. From RNA-dependent RNA polymerase (RdRp) assays in vitro, the NS5B containing P162T mutation (NS5BP162T) exhibited enhanced RdRp activity for different RNA templates. We further identified that the enhanced RdRp activity originated from increased initiation efficiency of RNA synthesis. These findings revealed a novel function for the NS5B residue 162 in modulating pestivirus replication.
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25
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Stenberg H, Leveringhaus E, Malmsten A, Dalin AM, Postel A, Malmberg M. Atypical porcine pestivirus-A widespread virus in the Swedish wild boar population. Transbound Emerg Dis 2021; 69:2349-2360. [PMID: 34331830 DOI: 10.1111/tbed.14251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/08/2021] [Accepted: 07/20/2021] [Indexed: 01/23/2023]
Abstract
The recently identified causative agent of congenital tremor in domestic piglets, atypical porcine pestivirus (APPV), was detected in serum from Swedish wild boar. A previous study from Sweden described APPV in domestic piglets suffering from congenital tremor, but the APPV situation in the wild boar population was unknown. In this study, 595 serum samples from wild boar originating from 13 counties in the south and central parts of Sweden, collected between 2000 and 2018, were analysed for the presence of the APPV-genome and for antibodies against the APPV-glycoprotein Erns . The results revealed that APPV is highly abundant in the Swedish wild boar population; 12% (73/595) were APPV-genome positive in serum and 72% (433/595) of the tested wild boars displayed APPV-specific antibodies. The present study also shows that APPV has been present in the Swedish wild boar population since at least the year 2000. The viral sequences obtained from the wild boars were highly similar to those obtained from Swedish domestic pigs positive for APPV and suffering from congenital tremor, suggesting a viral exchange between wild boars and domestic pigs. The high proportion of viraemic and seropositive wild boar is indicative of wild boar being an important reservoir for APPV.
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Affiliation(s)
- Hedvig Stenberg
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Elena Leveringhaus
- Institute for Virology, University of Veterinary Medicine Hannover, Hannover, Germany
| | | | - Anne-Marie Dalin
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Alexander Postel
- Institute for Virology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Maja Malmberg
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.,SLU Global Bioinformatics Centre, Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
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Šimenc L, Knific T, Toplak I. The Comparison of Honeybee Viral Loads for Six Honeybee Viruses (ABPV, BQCV, CBPV, DWV, LSV3 and SBV) in Healthy and Clinically Affected Honeybees with TaqMan Quantitative Real-Time RT-PCR Assays. Viruses 2021; 13:v13071340. [PMID: 34372546 PMCID: PMC8310196 DOI: 10.3390/v13071340] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 01/17/2023] Open
Abstract
The viral loads of acute bee paralysis virus (ABPV), black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Lake Sinai virus 3 (LSV3), and sacbrood bee virus (SBV) were determined in samples with the use of quantitative TaqMan real-time reverse transcription and polymerase chain reaction (RT-qPCR). A total of 108 samples of healthy adult honeybees from four differently located apiaries and samples of honeybees showing different clinical signs of viral infections from 89 apiaries were collected throughout Slovenia. The aim of this study was to discover correlations between viral loads and clinical signs in adult honeybees and confirm previously set threshold viral load levels between healthy and clinically affected honeybees. Within this study, two new RT-qPCR assays for quantification of LSV3 and SBV were developed. Statistically significant differences in viral loads of positive samples were identified between healthy and clinically affected honeybees for ABPV, CBPV, DWV, and SBV, while for BQCV and LSV3, no statistical differences were observed between both groups. Despite high detected LSV3 prevalence and viral loads around 6.00 log10 viral copies/bee, this lineage probably has a limited impact on the health status of honeybee colonies. The determined viral loads between 3.94 log10 and 13.17 log10 in positive samples for six viruses, collected over 10 consecutive months, including winter, present additional information of high viral load variations in healthy honeybee colonies.
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Affiliation(s)
- Laura Šimenc
- Virology Unit, Institute of Microbiology and Parasitology, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1115 Ljubljana, Slovenia;
- Correspondence:
| | - Tanja Knific
- Institute of Food Safety, Feed and Environment, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1115 Ljubljana, Slovenia;
| | - Ivan Toplak
- Virology Unit, Institute of Microbiology and Parasitology, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1115 Ljubljana, Slovenia;
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Bertani V, Prioni S, Di Lecce R, Gazza F, Ragionieri L, Merialdi G, Bonilauri P, Jagannathan V, Grassi S, Cabitta L, Paoli A, Morrone A, Sonnino S, Drögemüller C, Cantoni AM. A pathogenic HEXA missense variant in wild boars with Tay-Sachs disease. Mol Genet Metab 2021; 133:297-306. [PMID: 34119419 DOI: 10.1016/j.ymgme.2021.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 05/02/2021] [Accepted: 05/03/2021] [Indexed: 12/27/2022]
Abstract
Gangliosidoses are inherited lysosomal storage disorders caused by reduced or absent activity of either a lysosomal enzyme involved in ganglioside catabolism, or an activator protein required for the proper activity of a ganglioside hydrolase, which results in the intra-lysosomal accumulation of undegraded metabolites. We hereby describe morphological, ultrastructural, biochemical and genetic features of GM2 gangliosidosis in three captive bred wild boar littermates. The piglets were kept in a partially-free range farm and presented progressive neurological signs, starting at 6 months of age. Animals were euthanized at approximately one year of age due to their poor conditions. Neuropathogens were excluded as a possible cause of the signs. Gross examination showed a reduction of cerebral and cerebellar consistency. Central (CNS) and peripheral (PNS) nervous system neurons were enlarged and foamy, with severe and diffuse cytoplasmic vacuolization. Transmission electron microscopy (TEM) of CNS neurons demonstrated numerous lysosomes, filled by parallel or concentric layers of membranous electron-dense material, defined as membranous cytoplasmic bodies (MCB). Biochemical composition of gangliosides analysis from CNS revealed accumulation of GM2 ganglioside; furthermore, Hex A enzyme activity was less than 1% compared to control animals. These data confirmed the diagnosis of GM2 gangliosidosis. Genetic analysis identified, at a homozygous level, the presence of a missense nucleotide variant c.1495C > T (p Arg499Cys) in the hexosaminidase subunit alpha gene (HEXA), located within the GH20 hexosaminidase superfamily domain of the encoded protein. This specific HEXA variant is known to be pathogenic and associated with Tay-Sachs disease in humans, but has never been identified in other animal species. This is the first report of a HEXA gene associated Tay-Sachs disease in wild boars and provides a comprehensive description of a novel spontaneous animal model for this lysosomal storage disease.
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Affiliation(s)
- Valeria Bertani
- Department of Veterinary Science, University of Parma, Via Taglio, 8, 43100 Parma, Italy.
| | - Simona Prioni
- Department of Medical Biotechnology and Translational Medicine, University of Milano, Via Fratelli Cervi 93, 20129 Segrate, Italy
| | - Rosanna Di Lecce
- Department of Veterinary Science, University of Parma, Via Taglio, 8, 43100 Parma, Italy
| | - Ferdinando Gazza
- Department of Veterinary Science, University of Parma, Via Taglio, 8, 43100 Parma, Italy
| | - Luisa Ragionieri
- Department of Veterinary Science, University of Parma, Via Taglio, 8, 43100 Parma, Italy
| | - Giuseppe Merialdi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Pietro Fiorini, 5, 40127, Bologna, Italy
| | - Paolo Bonilauri
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Pietro Fiorini, 5, 40127, Bologna, Italy
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3001 Bern, Switzerland
| | - Sara Grassi
- Department of Medical Biotechnology and Translational Medicine, University of Milano, Via Fratelli Cervi 93, 20129 Segrate, Italy
| | - Livia Cabitta
- Department of Medical Biotechnology and Translational Medicine, University of Milano, Via Fratelli Cervi 93, 20129 Segrate, Italy
| | - Antonella Paoli
- Molecular and Cell Biology Laboratory, Paediatric Neurology Unit and Laboratories, Neuroscience Department, A. Meyer Children's Hospital, Florence, Italy
| | - Amelia Morrone
- Molecular and Cell Biology Laboratory, Paediatric Neurology Unit and Laboratories, Neuroscience Department, A. Meyer Children's Hospital, Florence, Italy; Department of Neurosciences, Psychology, Pharmacology and Child Health, University of Florence, Italy
| | - Sandro Sonnino
- Department of Medical Biotechnology and Translational Medicine, University of Milano, Via Fratelli Cervi 93, 20129 Segrate, Italy
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3001 Bern, Switzerland
| | - Anna Maria Cantoni
- Department of Veterinary Science, University of Parma, Via Taglio, 8, 43100 Parma, Italy
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Koltsova G, Koltsov A, Krutko S, Kholod N, Tulman ER, Kolbasov D. Growth Kinetics and Protective Efficacy of Attenuated ASFV Strain Congo with Deletion of the EP402 Gene. Viruses 2021; 13:v13071259. [PMID: 34203302 PMCID: PMC8309992 DOI: 10.3390/v13071259] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 11/16/2022] Open
Abstract
African swine fever (ASF) is an emerging disease threat to the swine industry worldwide. There is no vaccine against ASF, and progress is hindered by a lack of knowledge concerning the extent of ASFV strain diversity and the viral antigens conferring type-specific protective immunity in pigs. We have previously demonstrated that homologous ASFV serotype-specific proteins CD2v (EP402R) and/or C-type lectin are required for protection against challenge with the virulent ASFV strain Congo (Genotype I, Serogroup 2), and we have identified T-cell epitopes on CD2v which may be associated with serotype-specific protection. Here, using a cell-culture adapted derivative of the ASFV strain Congo (Congo-a) with specific deletion of the EP402R gene (ΔCongoCD2v) in swine vaccination/challenge experiments, we demonstrated that deletion of the EP402R gene results in the failure of ΔCongoCD2v to induce protection against challenge with the virulent strain Congo (Congo-v). While ΔCongoCD2v growth kinetics in COS-1 cells and primary swine macrophage culture were almost identical to parental Congo-a, replication of ΔCongoCD2v in vivo was significantly reduced compared with parental Congo-a. Our data support the idea that the CD2v protein is important for the ability of homologous live-attenuated vaccines to induce protective immunity against the ASFV strain Congo challenge in vivo.
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Affiliation(s)
- Galina Koltsova
- Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia; (A.K.); (S.K.); (N.K.); (D.K.)
- Correspondence:
| | - Andrey Koltsov
- Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia; (A.K.); (S.K.); (N.K.); (D.K.)
| | - Sergey Krutko
- Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia; (A.K.); (S.K.); (N.K.); (D.K.)
| | - Natalia Kholod
- Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia; (A.K.); (S.K.); (N.K.); (D.K.)
| | - Edan R. Tulman
- Center of Excellence for Vaccine Research, Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, CT 06269, USA;
| | - Denis Kolbasov
- Federal Research Centre for Virology and Microbiology, Academician Bakoulov Street 1, 601125 Volginsky, Russia; (A.K.); (S.K.); (N.K.); (D.K.)
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Reuscher CM, Schmidt L, Netsch A, Lamp B. Characterization of a Cytopathogenic Reporter CSFV. Viruses 2021; 13:1209. [PMID: 34201706 PMCID: PMC8310069 DOI: 10.3390/v13071209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/16/2021] [Accepted: 06/21/2021] [Indexed: 12/30/2022] Open
Abstract
Cytopathogenic (cp) pestiviruses frequently emerge in cattle that are persistently infected with the bovine viral diarrhea virus (BVDV) as a consequence of RNA recombination and mutation. They induce apoptosis in infected tissue cultures, are highly attenuated in the immunocompetent host, and unable to establish persistent infections after diaplacental infections. Cp strains of BVDV have been used as naturally attenuated live vaccines and for species-specific plaque reduction tests for the indirect serological detection of BVDV. Here, we present a genetically engineered cp strain of the classical swine fever virus (CSFV). Cytopathogenicity of the strain was induced by the insertion of ubiquitin embedded in a large NS3 to NS4B duplication. The CSFV RNA genome was stabilized by the inactivation of the NS2 autoprotease, hindering the deletion of the insertion and the reversion to a wild-type genome. Additional insertion of a mCherry gene at the 5'-end of the E2 gene allowed fluorescence-verified plaque reduction assays for CSFV, thus providing a novel, cost-efficient diagnostic tool. This genetically stabilized cp CSFV strain could be further used as a basis for potential new modified live vaccines. Taken together, we applied reverse genetics to rationally fixate a typical cp NS3 duplication in a CSFV genome.
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Affiliation(s)
| | | | | | - Benjamin Lamp
- Institute of Virology, Faculty of Veterinary Medicine, Justus-Liebig-University, Biomedical Research Center, Schubertstrasse 81, 35392 Giessen, Germany; (C.M.R.); (L.S.); (A.N.)
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30
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The E rns Carboxyterminus: Much More Than a Membrane Anchor. Viruses 2021; 13:v13071203. [PMID: 34201636 PMCID: PMC8310223 DOI: 10.3390/v13071203] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 12/12/2022] Open
Abstract
Pestiviruses express the unique essential envelope protein Erns, which exhibits RNase activity, is attached to membranes by a long amphipathic helix, and is partially secreted from infected cells. The RNase activity of Erns is directly connected with pestivirus virulence. Formation of homodimers and secretion of the protein are hypothesized to be important for its role as a virulence factor, which impairs the host's innate immune response to pestivirus infection. The unusual membrane anchor of Erns raises questions with regard to proteolytic processing of the viral polyprotein at the Erns carboxy-terminus. Moreover, the membrane anchor is crucial for establishing the critical equilibrium between retention and secretion and ensures intracellular accumulation of the protein at the site of virus budding so that it is available to serve both as structural component of the virion and factor controlling host immune reactions. In the present manuscript, we summarize published as well as new data on the molecular features of Erns including aspects of its interplay with the other two envelope proteins with a special focus on the biochemistry of the Erns membrane anchor.
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Postel A, Becher P. Genetically distinct pestiviruses pave the way to improved classical swine fever marker vaccine candidates based on the chimeric pestivirus concept. Emerg Microbes Infect 2021; 9:2180-2189. [PMID: 32962557 PMCID: PMC7580611 DOI: 10.1080/22221751.2020.1826893] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Classical swine fever (CSF) is one of the most important viral diseases of pigs. In many countries, the use of vaccines is restricted due to limitations of subunit vaccines with regard to efficacy and onset of protection as well as failure of live vaccines to differentiate infected from vaccinated animals (DIVA principle). Chimeric pestiviruses based on CSF virus (CSFV) and the related bovine viral diarrhea virus (BVDV) have been licensed as live marker vaccines in Europe and Asia, but cross-reactive antibodies can cause problems in DIVA application due to close antigenic relationship. To develop marker vaccine candidates with improved DIVA properties, three chimeric viruses were generated by replacing Erns of CSFV Alfort-Tübingen with homologue proteins of only distantly related pestiviruses. The chimeric viruses “Ra”, “Pro”, and “RaPro” contained Erns sequences of Norway rat and Pronghorn pestiviruses or a combination of both, respectively. In porcine cells, the “Pro” chimera replicated to high titers, while replication of the “Ra” chimera was limited. The “RaPro” chimera showed an intermediate phenotype. All vaccine candidates were attenuated in a vaccination/ challenge trial in pigs, but to different extents. Inoculation induced moderate to high levels of neutralizing antibodies that protected against infection with a genetically heterologous, highly virulent CSFV. Importantly, serum samples of vaccinated animals did not show any cross-reactivity in a CSFV Erns antibody ELISA. In conclusion, the Erns antigen from distantly related pestiviruses can provide a robust serological negative marker for a new generation of improved CSFV marker vaccines based on the chimeric pestivirus concept.
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Affiliation(s)
- Alexander Postel
- Institute of Virology, Department of Infectious Diseases, University of Veterinary Medicine, Hannover, Germany
| | - Paul Becher
- Institute of Virology, Department of Infectious Diseases, University of Veterinary Medicine, Hannover, Germany
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32
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Early and Solid Protection Afforded by the Thiverval Vaccine Provides Novel Vaccination Alternatives Against Classical Swine Fever Virus. Vaccines (Basel) 2021; 9:vaccines9050464. [PMID: 34066376 PMCID: PMC8148177 DOI: 10.3390/vaccines9050464] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 12/20/2022] Open
Abstract
Classical swine fever virus (CSFV) remains a challenge for the porcine industry. Inefficient vaccination programs in some endemic areas may have contributed to the emergence of low and moderate virulence CSFV variants. This work aimed to expand and update the information about the safety and efficacy of the CSFV Thiverval-strain vaccine. Two groups of pigs were vaccinated, and a contact and control groups were also included. Animals were challenged with a highly virulent CSFV strain at 21- or 5-days post vaccination (dpv). The vaccine induced rapid and strong IFN-α response, mainly in the 5-day immunized group, and no vaccine virus transmission was detected. Vaccinated pigs showed humoral response against CSFV E2 and Erns glycoproteins, with neutralising activity, starting at 14 days post vaccination (dpv). Strong clinical protection was afforded in all the vaccinated pigs as early as 5 dpv. The vaccine controlled viral replication after challenge, showing efficient virological protection in the 21-day immunized pigs despite being housed with animals excreting high CSFV titres. These results demonstrate the high efficacy of the Thiverval strain against CSFV replication. Its early protection capacity makes it a useful alternative for emergency vaccination and a consistent tool for CSFV control worldwide.
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Bohórquez JA, Sozzi E, Wang M, Alberch M, Abad X, Gaffuri A, Lelli D, Rosell R, Pérez LJ, Moreno A, Ganges L. The new emerging ovine pestivirus can infect pigs and confers strong protection against classical swine fever virus. Transbound Emerg Dis 2021; 69:1539-1555. [PMID: 33896109 DOI: 10.1111/tbed.14119] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/09/2021] [Accepted: 04/19/2021] [Indexed: 12/16/2022]
Abstract
Several emerging pestiviruses have been reported lately, some of which have proved to cause disease. Recently, a new ovine pestivirus (OVPV), isolated from aborted lambs, with high genetic identity to classical swine fever virus (CSFV), has proved to induce reproductive disorders in pregnant ewes. OVPV also generated strong serological and molecular cross-reaction with CSFV. To assess the capacity of OVPV to infect swine, twelve piglets were infected either by intranasal or intramuscular route. Daily clinical evaluation and weekly samplings were performed to determine pathogenicity, viral replication and excretion and induction of immune response. Five weeks later, two pigs from each group were euthanized and tissue samples were collected to study viral replication and distribution. OVPV generated only mild clinical signs in the piglets, including wasting and polyarthritis. The virus was able to replicate, as shown by the RNA levels found in sera and swabs and persisted in tonsil for at least 5 weeks. Viral replication activated the innate and adaptive immunity, evidenced by the induction of interferon-alpha levels early after infection and cross-neutralizing antibodies against CSFV, including humoural response against CSFV E2 and Erns glycoproteins. Close antigenic relation between OVPV and CSFV genotype 2.3 was detected. To determine the OVPV protection against CSFV, the OVPV-infected pigs were challenged with a highly virulent strain. Strong clinical, virological and immunological protection was generated in the OVPV-infected pigs, in direct contrast with the infection control group. Our findings show, for the first time, the OVPV capacity to infect swine, activate immunity, and the robust protection conferred against CSFV. In addition, their genetic and antigenic similarities, the close relationship between both viruses, suggest their possible coevolution as two branches stemming from a shared origin at the same time in two different hosts.
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Affiliation(s)
| | - Enrica Sozzi
- Istituto Zooprofilattico Sperimentale della Lombardia e Dell'Emilia Romagna, Brescia, Italy
| | - Miaomiao Wang
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
| | - Mònica Alberch
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
| | - Xavier Abad
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
| | - Alessandra Gaffuri
- Istituto Zooprofilattico Sperimentale della Lombardia e Dell'Emilia Romagna, Brescia, Italy
| | - Davide Lelli
- Istituto Zooprofilattico Sperimentale della Lombardia e Dell'Emilia Romagna, Brescia, Italy
| | - Rosa Rosell
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain.,Departament d'Agricultura, Ramadería, Pesca i Alimentació (DARP), Generalitat de Catalunya, Barcelona, Spain
| | - Lester Josue Pérez
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ana Moreno
- Istituto Zooprofilattico Sperimentale della Lombardia e Dell'Emilia Romagna, Brescia, Italy
| | - Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
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Park Y, Oh Y, Wang M, Ganges L, Bohórquez JA, Park S, Gu S, Park J, Lee S, Kim J, Sohn EJ. A Novel E2 Glycoprotein Subunit Marker Vaccine Produced in Plant Is Able to Prevent Classical Swine Fever Virus Vertical Transmission after Double Vaccination. Vaccines (Basel) 2021; 9:vaccines9050418. [PMID: 33922120 PMCID: PMC8143534 DOI: 10.3390/vaccines9050418] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/16/2021] [Accepted: 04/18/2021] [Indexed: 12/16/2022] Open
Abstract
The efficacy of a novel subunit vaccine candidate, based in the CSFV E2 glycoprotein produced in plants to prevent classical swine fever virus (CSFV) vertical transmission, was evaluated. A Nicotiana benthamiana tissue culture system was used to obtain a stable production of the E2-glycoprotein fused to the porcine Fc region of IgG. Ten pregnant sows were divided into three groups: Groups 1 and 2 (four sows each) were vaccinated with either 100 μg/dose or 300 μg/dose of the subunit vaccine at 64 days of pregnancy. Group 3 (two sows) was injected with PBS. Groups 1 and 2 were boosted with the same vaccine dose. At 10 days post second vaccination, the sows in Groups 2 and 3 were challenged with a highly virulent CSFV strain. The vaccinated sows remained clinically healthy and seroconverted rapidly, showing efficient neutralizing antibodies. The fetuses from vaccinated sows did not show gross lesions, and all analyzed tissue samples tested negative for CSFV replication. However, fetuses of non-vaccinated sows had high CSFV replication in tested tissue samples. The results suggested that in vaccinated sows, the plant produced E2 marker vaccine induced the protective immunogenicity at challenge, leading to protection from vertical transmission to fetuses.
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Affiliation(s)
- Youngmin Park
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
| | - Yeonsu Oh
- College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Korea;
| | - Miaomiao Wang
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (M.W.); (L.G.); (J.A.B.)
| | - Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (M.W.); (L.G.); (J.A.B.)
| | - José Alejandro Bohórquez
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (M.W.); (L.G.); (J.A.B.)
| | - Soohong Park
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
| | - Sungmin Gu
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
| | - Jungae Park
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
| | - Sangmin Lee
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
| | - Jongkook Kim
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
| | - Eun-Ju Sohn
- BioApplications Inc., Pohang 37668, Korea; (Y.P.); (S.P.); (S.G.); (J.P.); (S.L.); (J.K.)
- Correspondence: ; Tel.: +82-54-223-2090; Fax: +80-54-223-2088
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Porcine Complement Regulatory Protein CD46 Is a Major Receptor for Atypical Porcine Pestivirus but Not for Classical Swine Fever Virus. J Virol 2021; 95:JVI.02186-20. [PMID: 33568504 PMCID: PMC8104093 DOI: 10.1128/jvi.02186-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/28/2021] [Indexed: 01/02/2023] Open
Abstract
Pestiviruses comprise animal pathogens such as classical swine fever virus (CSFV) and bovine viral diarrhea virus (BVDV) that cause notifiable diseases with great economic impact. Several additional pestivirus species affecting animal health were recently identified, including atypical porcine pestivirus (APPV). Pestiviruses such as bovine viral diarrhea virus (BVDV) and classical swine fever virus (CSFV) belong to the family Flaviviridae and represent pathogens of outstanding veterinary relevance. Pestiviruses enter cells via receptor-mediated endocytosis. For entry in bovine cells, complement regulatory protein CD46bov serves as a cellular receptor for BVDV. In this study, the role of porcine CD46pig in cellular entry was investigated for the recently discovered atypical porcine pestivirus (APPV), CSFV, and Bungowannah virus (BuPV) in order to elucidate the observed differences in host cell tropism. A cell culture-adapted APPV variant, which shows enhanced viral replication in vitro, was generated and demonstrated a strict tropism of APPV for porcine cells. One of the porcine cell lines displayed areas of CD46pig-expressing cells and areas of nonexpressing cells, and one single cell line revealed not to express any CD46pig. The CD46pig-deficient porcine lymphoma cell line, known to facilitate CSFV replication, was the only porcine cell line nonpermissive to APPV, indicating a significant difference in the entry mechanism of APPV and CSFV. Infection experiments with a set of genetically engineered CD46pig knockout cells confirmed that CD46pig is a major receptor of APPV as CD46bov is for BVDV. In contrast, it is apparently not an essential determinant in host cell entry of other porcine pestiviruses such as CSFV and BuPV. Existence of a CD46pig-independent entry mechanism illustrates that the pestiviral entry process is more diverse than previously recognized. IMPORTANCE Pestiviruses comprise animal pathogens such as classical swine fever virus (CSFV) and bovine viral diarrhea virus (BVDV) that cause notifiable diseases with great economic impact. Several additional pestivirus species affecting animal health were recently identified, including atypical porcine pestivirus (APPV). APPV is associated with health problems in piglets and is highly abundant in pig populations worldwide. Complement control protein CD46 serves as a receptor for diverse bacterial and viral pathogens, including particular adenoviruses, herpesviruses, measles virus (MeV), and BVDV. Porcine CD46 (CD46pig) was suggested to be a major receptor for CSFV. Here, we identified remarkable differences in relevance of CD46pig during entry of porcine pestiviruses. Resembling BVDV, efficient APPV infection in cell culture depends on CD46pig, while other porcine pestiviruses can efficiently enter and infect cells in the absence of CD46pig. Thus, the study provides insights into the entry process of these pathogens and may help to understand differences in their biology.
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Fan J, Liao Y, Zhang M, Liu C, Li Z, Li Y, Li X, Wu K, Yi L, Ding H, Zhao M, Fan S, Chen J. Anti-Classical Swine Fever Virus Strategies. Microorganisms 2021; 9:microorganisms9040761. [PMID: 33917361 PMCID: PMC8067343 DOI: 10.3390/microorganisms9040761] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/24/2021] [Accepted: 04/02/2021] [Indexed: 12/23/2022] Open
Abstract
Classical swine fever (CSF), caused by CSF virus (CSFV), is a highly contagious swine disease with high morbidity and mortality, which has caused significant economic losses to the pig industry worldwide. Biosecurity measures and vaccination are the main methods for prevention and control of CSF since no specific drug is available for the effective treatment of CSF. Although a series of biosecurity and vaccination strategies have been developed to curb the outbreak events, it is still difficult to eliminate CSF in CSF-endemic and re-emerging areas. Thus, in addition to implementing enhanced biosecurity measures and exploring more effective CSF vaccines, other strategies are also needed for effectively controlling CSF. Currently, more and more research about anti-CSFV strategies was carried out by scientists, because of the great prospects and value of anti-CSFV strategies in the prevention and control of CSF. Additionally, studies on anti-CSFV strategies could be used as a reference for other viruses in the Flaviviridae family, such as hepatitis C virus, dengue virus, and Zika virus. In this review, we aim to summarize the research on anti-CSFV strategies. In detail, host proteins affecting CSFV replication, drug candidates with anti-CSFV effects, and RNA interference (RNAi) targeting CSFV viral genes were mentioned and the possible mechanisms related to anti-CSFV effects were also summarized.
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Affiliation(s)
- Jindai Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Yingxin Liao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Mengru Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Chenchen Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Zhaoyao Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Yuwan Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Xiaowen Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Keke Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Lin Yi
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Hongxing Ding
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Mingqiu Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: (S.F.); (J.C.); Tel.: +86-20-8528-8017 (J.C.)
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (J.F.); (Y.L.); (M.Z.); (C.L.); (Z.L.); (Y.L.); (X.L.); (K.W.); (L.Y.); (H.D.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: (S.F.); (J.C.); Tel.: +86-20-8528-8017 (J.C.)
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Bazarragchaa E, Isoda N, Kim T, Tetsuo M, Ito S, Matsuno K, Sakoda Y. Efficacy of Oral Vaccine against Classical Swine Fever in Wild Boar and Estimation of the Disease Dynamics in the Quantitative Approach. Viruses 2021; 13:v13020319. [PMID: 33672749 PMCID: PMC7924559 DOI: 10.3390/v13020319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/09/2021] [Accepted: 02/18/2021] [Indexed: 11/16/2022] Open
Abstract
Classical swine fever virus (CSFV) in the wild boar population has been spreading in Japan, alongside outbreaks on pigs, since classical swine fever (CSF) reemerged in September 2018. The vaccination using oral bait vaccine was initially implemented in Gifu prefecture in March 2019. In the present study, antibodies against CSFV in wild boar were assessed in 1443 captured and dead wild boars in Gifu prefecture. After the implementation of oral vaccination, the increase of the proportion of seropositive animals and their titer in wild boars were confirmed. Quantitative analysis of antigen and antibodies against CSFV in wild boar implies potential disease diversity in the wild boar population. Animals with status in high virus replication (Ct < 30) and non- or low-immune response were confirmed and were sustained at a certain level after initial oral vaccination. Through continuous vaccination periods, the increase of seroprevalence among wild boar and the decrease of CSFV-positive animals were observed. The epidemiological analysis based on the quantitative virological outcomes could provide more information on the efficacy of oral vaccination and dynamics of CSF in the wild boar population, which will help to improve the implementation of control measures for CSF in countries such as Japan and neighboring countries.
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Affiliation(s)
- Enkhbold Bazarragchaa
- Laboratory of Microbiology, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-Ku, Sapporo 060-0818, Hokkaido, Japan; (E.B.); (T.K.); (M.T.)
| | - Norikazu Isoda
- Laboratory of Microbiology, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-Ku, Sapporo 060-0818, Hokkaido, Japan; (E.B.); (T.K.); (M.T.)
- Unit of Risk Analysis and Management, Research Center for Zoonosis Control, Hokkaido University, Kita 20, Nishi 10, Kita-Ku, Sapporo 001-0020, Hokkaido, Japan; (S.I.); (K.M.)
- Correspondence: (N.I.); (Y.S.); Tel.: +81-11-706-5208 (N.I.); +81-11-706-5207 (Y.S.)
| | - Taksoo Kim
- Laboratory of Microbiology, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-Ku, Sapporo 060-0818, Hokkaido, Japan; (E.B.); (T.K.); (M.T.)
| | - Madoka Tetsuo
- Laboratory of Microbiology, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-Ku, Sapporo 060-0818, Hokkaido, Japan; (E.B.); (T.K.); (M.T.)
| | - Satoshi Ito
- Unit of Risk Analysis and Management, Research Center for Zoonosis Control, Hokkaido University, Kita 20, Nishi 10, Kita-Ku, Sapporo 001-0020, Hokkaido, Japan; (S.I.); (K.M.)
| | - Keita Matsuno
- Unit of Risk Analysis and Management, Research Center for Zoonosis Control, Hokkaido University, Kita 20, Nishi 10, Kita-Ku, Sapporo 001-0020, Hokkaido, Japan; (S.I.); (K.M.)
- International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Kita 20, Nishi 10, Kita-Ku, Sapporo 001-0020, Hokkaido, Japan
| | - Yoshihiro Sakoda
- Laboratory of Microbiology, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-Ku, Sapporo 060-0818, Hokkaido, Japan; (E.B.); (T.K.); (M.T.)
- International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Kita 20, Nishi 10, Kita-Ku, Sapporo 001-0020, Hokkaido, Japan
- Correspondence: (N.I.); (Y.S.); Tel.: +81-11-706-5208 (N.I.); +81-11-706-5207 (Y.S.)
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Chen JY, Wu CM, Chen ZW, Liao CM, Deng MC, Chia MY, Huang C, Chien MS. Evaluation of classical swine fever E2 (CSF-E2) subunit vaccine efficacy in the prevention of virus transmission and impact of maternal derived antibody interference in field farm applications. Porcine Health Manag 2021; 7:9. [PMID: 33431028 PMCID: PMC7798205 DOI: 10.1186/s40813-020-00188-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/26/2020] [Indexed: 01/29/2023] Open
Abstract
Background Classical swine fever (CSF) is one of the most devastating pig diseases that affect the swine industry worldwide. Besides stamping out policy for eradication, immunization with vaccines of live attenuated CSF or the CSF-E2 subunit is an efficacious measure of disease control. However, after decades of efforts, it is still hard to eliminate CSF from endemically affected regions and reemerging areas. Most of previous studies demonstrated the efficacy of different CSF vaccines in laboratories under high containment conditions, which may not represent the practical performance in field farms. The inadequate vaccine efficacy induced by unrestrained factors may lead to chronic or persistent CSF infection in animals that develop a major source for virus shedding among pig populations. In this study, a vaccination-challenge-cohabitation trial on specific-pathogen-free (SPF) pigs and long-term monitoring of conventional sows and their offspring were used to evaluate the efficacy and the impact of maternally derived antibody (MDA) interference on CSF vaccines in farm applications. Results The trials demonstrated higher neutralizing antibody (NA) titers with no clinical symptoms and significant pathological changes in the CSF-E2 subunit vaccine immunized group after CSFV challenge. Additionally, none of the sentinel pigs were infected during cohabitation indicating that the CSF-E2 subunit vaccine could provoke adequately acquired immunity to prevent horizontal transmission. In field farm applications, sows immunized with CSF-E2 subunit vaccine revealed an average of higher and consistent antibody level with significant reduction of CSF viral RNA detection via saliva monitoring in contrast to those of live attenuated CSF vaccine immunized sows possessing diverse antibody titer distributions and higher viral loads. Furthermore, early application of the CSF-E2 subunit vaccine in 3-week-old piglets illustrated no MDA interference on primary immunization and could elicit consistent and long-lasting adequate antibody response suggesting the flexibility of CSF-E2 subunit vaccine on vaccination program determination. Conclusions The CSF-E2 subunit vaccine demonstrated significant efficacy and no MDA interference for immunization in both pregnant sows and piglets. These advantages provide a novel approach to avoid possible virus shedding in sow population and MDA interference in piglets for control of CSF in field farm applications. Supplementary Information The online version contains supplementary material available at 10.1186/s40813-020-00188-6.
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Affiliation(s)
- Jing-Yuan Chen
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan, Republic of China
| | - Chi-Ming Wu
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan, Republic of China
| | - Zeng-Weng Chen
- Animal Technology Laboratories, Agricultural Technology Research Institute, No. 52, Kedong 2nd Rd., Zhunan Township, Miaoli County, 350401, Taiwan, Republic of China
| | - Chih-Ming Liao
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan, Republic of China
| | - Ming-Chung Deng
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, Taipei, 25158, Taiwan, Republic of China
| | - Min-Yuan Chia
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan, Republic of China
| | - Chienjin Huang
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan, Republic of China.
| | - Maw-Sheng Chien
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, 145 Xingda Road, Taichung, 40227, Taiwan, Republic of China.
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Stalder S, Marti H, Borel N, Mattmann P, Vogler B, Wolfrum N, Albini S. Detection of Chlamydiaceae in Swiss wild birds sampled at a bird rehabilitation centre. Vet Rec Open 2020; 7:e000437. [PMID: 33224510 PMCID: PMC7662422 DOI: 10.1136/vetreco-2020-000437] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/23/2020] [Accepted: 10/13/2020] [Indexed: 12/02/2022] Open
Abstract
Background Annually, 800–1500 wild birds are admitted to the rehabilitation centre of the Swiss Ornithological Institute, Sempach, Lucerne, Switzerland. The workers of the centre come in close contact with the avian patients and might therefore be exposed to zoonotic agents shed by these birds, such as Chlamydia psittaci. Methods In the present study, 91 choanal, 91 cloacal and 267 faecal swabs from 339 wild birds of 42 species were investigated using a stepwise diagnostic approach. Results Chlamydiaceae were detected in 0.9 per cent (0.3–2.6 per cent) of birds (n=3), all of them members of the Columbidae family. The Chlamydiaceae species of two of these birds (one Eurasian collared dove, one fancy pigeon) were identified as C psittaci types B and E by PCR and outer membrane protein A genotyping. Conclusion The findings of the current study suggest that zoonotic transmission of Chlamydiaceae is very unlikely for songbird and waterfowl species tested herein, while pigeons might pose a risk to workers at rehabilitation centres.
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Affiliation(s)
- Sandro Stalder
- National Reference Centre for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Hanna Marti
- Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | - Nicole Borel
- Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | - Prisca Mattmann
- Swiss Ornithological Institute, Sempach, Lucerne, Switzerland
| | - Barbara Vogler
- National Reference Centre for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Nina Wolfrum
- National Reference Centre for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Sarah Albini
- National Reference Centre for Poultry and Rabbit Diseases, Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
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Wang Q, Liu H, Xu L, Li J, Wu H, Yang C, Chen X, Deng Y, Sun Y, Tu C, Chen N, Gong W, Chen G. Different clinical presentations of subgenotype 2.1 strain of classical swine fever infection in weaned piglets and adults, and long-term cross-protection conferred by a C-strain vaccine. Vet Microbiol 2020; 253:108915. [PMID: 33309157 DOI: 10.1016/j.vetmic.2020.108915] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/28/2020] [Indexed: 12/17/2022]
Abstract
Classical swine fever is an important swine disease in China, and sporadic outbreaks with mild clinical signs despite compulsory vaccination have raised questions about the virulence and pathogenicity of prevalent subgenotype 2.1 strains, and the ability of C-strain vaccines to cross-protect against them. To investigate this, three field isolates were evaluated in experimentally infected piglets and compared with the highly virulent reference Shimen strain. Clinical signs for the field strains ranged from mild to severe, and mortality ranged from 0 to 80 %. These data show differences in virulence among the subgenotype 2.1 field isolates and support the use of field strain GD191 as a genotype 2 challenge virus to assess efficacy of C-strain vaccines. In contrast to the historical genotype 1 strain, which caused acute infection with significant virus shedding in non-vaccinated animals, the subgenotype 2.1 GD191 strain produced different clinical manifestations in weaned piglets and adults. Adult pigs showed subclinical infection with viral shedding, whereas weaned piglets showed overt signs of infection. Efficacy of, and duration of immunity conferred by a C-strain vaccine were assessed using the reference Shimen strain and field isolate GD191 at 12 and 15 months after vaccination. A robust antibody response and sterilising protection were seen in all vaccinated animals and lasted up to 15 months post-vaccination. This study confirms that C-strain vaccines confer both clinical and virological protection against the historical genotype 1 Shimen strain and cross-protection against the prevalent genotype 2 field strain.
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Affiliation(s)
- Qin Wang
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Huanhuan Liu
- Boehringer Ingelheim Vetmedica (China) Co. Ltd., Taizhou 225300, People's Republic of China
| | - Lu Xu
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Junping Li
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Huawei Wu
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Chenghuai Yang
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Xiaochun Chen
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Yong Deng
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China
| | - Yanyong Sun
- Boehringer Ingelheim Vetmedica (China) Co. Ltd., Taizhou 225300, People's Republic of China
| | - Changchun Tu
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, People's Republic of China
| | - Ning Chen
- Boehringer Ingelheim Vetmedica (China) Co. Ltd., Taizhou 225300, People's Republic of China.
| | - Wenjie Gong
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, People's Republic of China; Key Laboratory of Zoonoses Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China.
| | - Guanghua Chen
- Office International des Epizooties/National Reference Laboratory for Classical Swine Fever, China Institute of Veterinary Drug Control, Beijing 100081, People's Republic of China.
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Ganges L, Crooke HR, Bohórquez JA, Postel A, Sakoda Y, Becher P, Ruggli N. Classical swine fever virus: the past, present and future. Virus Res 2020; 289:198151. [PMID: 32898613 DOI: 10.1016/j.virusres.2020.198151] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/24/2020] [Accepted: 08/28/2020] [Indexed: 12/22/2022]
Abstract
Classical swine fever (CSF) is among the most relevant viral epizootic diseases of swine. Due to its severe economic impact, CSF is notifiable to the world organisation for animal health. Strict control policies, including systematic stamping out of infected herds with and without vaccination, have permitted regional virus eradication. Nevertheless, CSF virus (CSFV) persists in certain areas of the world and has re-emerged regularly. This review summarizes the basic established knowledge in the field and provides a comprehensive and updated overview of the recent advances in fundamental CSFV research, diagnostics and vaccine development. It covers the latest discoveries on the genetic diversity of pestiviruses, with implications for taxonomy, the progress in understanding disease pathogenesis, immunity against acute and persistent infections, and the recent findings in virus-host interactions and virulence determinants. We also review the progress and pitfalls in the improvement of diagnostic tools and the challenges in the development of modern and efficacious marker vaccines compatible with serological tests for disease surveillance. Finally, we highlight the gaps that require research efforts in the future.
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Affiliation(s)
- Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, Institute of Agrifood Research and Technology, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain.
| | - Helen R Crooke
- Virology Department, Animal and Plant Health Agency, APHA-Weybridge, Woodham Lane, New Haw, Addlestone, KT15 3NB, UK
| | - Jose Alejandro Bohórquez
- OIE Reference Laboratory for Classical Swine Fever, Institute of Agrifood Research and Technology, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - Alexander Postel
- EU & OIE Reference Laboratory for Classical Swine Fever, Institute of Virology, University of Veterinary Medicine, Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Yoshihiro Sakoda
- Laboratory of Microbiology, Faculty of Veterinary Medicine, Hokkaido University, Kita 18 Nishi 9, Kita-ku, Sapporo, 060-0818, Japan
| | - Paul Becher
- EU & OIE Reference Laboratory for Classical Swine Fever, Institute of Virology, University of Veterinary Medicine, Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Nicolas Ruggli
- The Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland; Department of Infectious Diseases and Pathobiology, University of Bern, Bern, Switzerland
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Occurrence of Chlamydiaceae in Raptors and Crows in Switzerland. Pathogens 2020; 9:pathogens9090724. [PMID: 32887370 PMCID: PMC7558692 DOI: 10.3390/pathogens9090724] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/21/2020] [Accepted: 08/29/2020] [Indexed: 12/26/2022] Open
Abstract
Bacteria of the family Chlamydiaceae are globally disseminated and able to infect many bird species. So far, 11 species of Chlamydia have been detected in wild birds, and several studies found chlamydial strains classified as genetically intermediate between Chlamydia (C.) psittaci and C.abortus. Recently, a group of these intermediate strains was shown to form a separate species, i.e., C.buteonis. In the present study, 1128 samples from 341 raptors of 16 bird species and 253 corvids representing six species were examined using a stepwise diagnostic approach. Chlamydiaceae DNA was detected in 23.7% of the corvids and 5.9% of the raptors. In corvids, the most frequently detected Chlamydia species was C.psittaci of outer membrane protein A (ompA) genotype 1V, which is known to have a host preference for corvids. The most frequently detected ompA genotype in raptors was M56. Furthermore, one of the raptors harbored C.psittaci 1V, and two others carried genotype A. C.buteonis was not detected in the bird population investigated, so it remains unknown whether this species occurs in Switzerland. The infection rate of Chlamydiaceae in corvids was high compared to rates reported in other wild bird species, but neither Chlamydiaceae-positive corvids nor raptors showed overt signs of disease. Since the Chlamydiaceae of both, raptors and crows were identified as C.psittaci and all C.psittaci genotypes are considered to be zoonotic, it can be suggested that raptors and crows pose a potential hazard to the health of their handlers.
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Izzati UZ, Hoa NT, Lan NT, Diep NV, Fuke N, Hirai T, Yamaguchi R. Pathology of the outbreak of subgenotype 2.5 classical swine fever virus in northern Vietnam. Vet Med Sci 2020; 7:164-174. [PMID: 32781492 PMCID: PMC7840204 DOI: 10.1002/vms3.339] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 06/22/2020] [Accepted: 07/20/2020] [Indexed: 11/06/2022] Open
Abstract
Classical swine fever (CSF) is an endemic disease in southeastern Asia and is one of the most important swine diseases in Vietnam. This study was conducted to characterize the pathology of natural cases of CSF in northern Vietnam in 2018 and their genetic prevalence. A total of 10 representative pigs were collected from four provinces (Hung Yen, Ha Noi, Quang Ninh and Thai Binh) during five outbreaks and examined pathologically. The gross and histopathological findings showed the disease was expressed as the acute or the subacute to chronic form of CSF, depending on the age of the animals. The most consistently observed lesions associated with infection by the classical swine fever virus (CSFV) included lymphoid depletions in tonsils, lymph node and spleen; histiocytic hyperplasia in spleen; cerebral haemorrhage; perivascular cuffing in the brain; renal erythrodiapedesis; urothelial vacuolation and degeneration and interstitial pneumonia. The immunohistochemical findings showed a ubiquitous CSFV antigen mainly in the monocytes/macrophages and in the epithelial and endothelial cells in various organs. CSFV neurotropism was also found in the small neurons of the cerebrum and the ganglia of the myenteric plexus. Analysis of the full-length envelope protein (E2) genome sequence showed that all strains were genetically clustered into subgenotype 2.5, sharing a nucleotide identity of 94.0%-100.00%. Based on the results of this study, the strain was categorized as a moderately virulent CSFV.
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Affiliation(s)
- Uda Zahli Izzati
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Nguyen Thi Hoa
- Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Gia Lam, Hanoi, Vietnam
| | - Nguyen Thi Lan
- Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Gia Lam, Hanoi, Vietnam
| | - Nguyen Van Diep
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.,Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Gia Lam, Hanoi, Vietnam
| | - Naoyuki Fuke
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Takuya Hirai
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Ryoji Yamaguchi
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
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Stenberg H, Jacobson M, Malmberg M. Detection of atypical porcine pestivirus in Swedish piglets with congenital tremor type A-II. BMC Vet Res 2020; 16:260. [PMID: 32727473 PMCID: PMC7389371 DOI: 10.1186/s12917-020-02445-w] [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: 10/28/2019] [Accepted: 06/24/2020] [Indexed: 01/16/2023] Open
Abstract
Background Congenital tremor (CT) type A-II is a neurological disorder characterized by tremor of the head and body of newborn piglets. The suggested causative agent of the disease is the recently found atypical porcine pestivirus (APPV). The virus has been detected in piglets suffering from congenital tremor in central Europe, South and North America and in China but no studies has so far been performed in the Nordic countries. The overarching goal of this study was to investigate if APPV is present in the brain tissue of Swedish piglets suffering from congenital tremor. From June 2017 – June 2018, 15 piglets from four Swedish farms with ongoing outbreaks of congenital tremor and 13 piglets with splay leg originating from four different farms, were investigated for presence of APPV RNA in brain tissue. Matched healthy control piglets (n = 8) were also investigated. Two APPV-specific RT-qPCR methods targeting the NS3 and NS5B region, respectively, were used. A retrospective study was performed on material from Swedish piglets with congenital tremor sampled in 2004 (n = 11) and 2011/2012 (n = 3) using the described APPV-specific RT-qPCR methods. The total number of piglets with signs of CT in this study was 29. Results Atypical porcine pestivirus-RNA was detected in 93% (27/29) of the piglets suffering from congenital tremor. All piglets with congenital tremor from 2004 (n = 11) and 2012 (n = 3) were PCR-positive with respect to APPV, whereas, all of the healthy controls (n = 11) were negative. The piglets with congenital tremor sampled 2017–2018 had an odds ratio of 91.8 (95% CI 3.9128 to 2153.7842, z = 2.807, P = 0.0050) to test positive for APPV by qRT-PCR compared to the healthy piglets (Fishers exact test p < 0.0001). These findings make it interesting to continue investigating APPV in the Swedish pig-population. Conclusion This is the first description of atypical porcine pestivirus in piglets suffering from congenital tremor type A-II in Sweden and the Nordic countries. The virus has been present in the Swedish pig population since at least 2004.
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Affiliation(s)
- Hedvig Stenberg
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 75007, Uppsala, Sweden.
| | - Magdalena Jacobson
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, Box 7054, 75007, Uppsala, Sweden
| | - Maja Malmberg
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 75007, Uppsala, Sweden.,SLU Global Bioinformatics Centre, Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 7023, 75007, Uppsala, Sweden
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Decrypting the Origin and Pathogenesis in Pregnant Ewes of a New Ovine Pestivirus Closely Related to Classical Swine Fever Virus. Viruses 2020; 12:v12070775. [PMID: 32709168 PMCID: PMC7411581 DOI: 10.3390/v12070775] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/13/2020] [Accepted: 07/15/2020] [Indexed: 02/07/2023] Open
Abstract
This study shows the origin and the pathogenic role of a novel ovine pestivirus (OVPV) isolated in 2017 in Italy, as a pathogenic agent causing severe abortions after infection in pregnant ewes and high capacity for virus trans-placental transmission as well as the birth of lambs suffering OVPV-persistent infection. The OVPV infection induced early antibody response detected by the specific ELISA against classical swine fever virus (CSFV), another important virus affecting swine. The neutralizing antibody response were similar against CSFV strains from genotype 2 and the OVPV. These viruses showed high identity in the B/C domain of the E2-glycoprotein. Close molecular diagnostics cross-reactivity between CSFV and OVPV was found and a new OVPV molecular assay was developed. The phylodynamic analysis showed that CSFV seems to have emerged as the result of an inter-species jump of Tunisian sheep virus (TSV) from sheep to pigs. The OVPV and the CSFV share the TSV as a common ancestor, emerging around 300 years ago. This suggests that the differentiation of TSV into two dangerous new viruses for animal health (CSFV and OVPV) was likely favored by human intervention for the close housing of multiple species for intensive livestock production.
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Bohórquez JA, Muñoz-González S, Pérez-Simó M, Muñoz I, Rosell R, Coronado L, Domingo M, Ganges L. Foetal Immune Response Activation and High Replication Rate during Generation of Classical Swine Fever Congenital Infection. Pathogens 2020; 9:pathogens9040285. [PMID: 32295279 PMCID: PMC7238013 DOI: 10.3390/pathogens9040285] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/09/2020] [Accepted: 04/14/2020] [Indexed: 12/16/2022] Open
Abstract
Classical swine fever virus (CSFV) induces trans-placental transmission and congenital viral persistence; however, the available information is not updated. Three groups of sows were infected at mid-gestation with either a high, moderate or low virulence CSFV strains. Foetuses from sows infected with high or low virulence strain were obtained before delivery and piglets from sows infected with the moderate virulence strain were studied for 32 days after birth. The low virulence strain generated lower CSFV RNA load and the lowest proportion of trans-placental transmission. Severe lesions and mummifications were observed in foetuses infected with the high virulence strain. Sows infected with the moderately virulence strain showed stillbirths and mummifications, one of them delivered live piglets, all CSFV persistently infected. Efficient trans-placental transmission was detected in sows infected with the high and moderate virulence strain. The trans-placental transmission occurred before the onset of antibody response, which started at 14 days after infection in these sows and was influenced by replication efficacy of the infecting strain. Fast and solid immunity after sow vaccination is required for prevention of congenital viral persistence. An increase in the CD8+ T-cell subset and IFN-alpha response was found in viremic foetuses, or in those that showed higher viral replication in tissue, showing the CSFV recognition capacity by the foetal immune system after trans-placental infection.
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Affiliation(s)
- José Alejandro Bohórquez
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
| | - Sara Muñoz-González
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
| | - Marta Pérez-Simó
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
| | - Iván Muñoz
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
| | - Rosa Rosell
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
- Departament d’Agricultura, Ramadería, Pesca, Alimentació I Medi Natural i Rural (DAAM), 08007 Generalitat de Catalunya, Spain
| | - Liani Coronado
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
- Centro Nacional de Sanidad Agropecuaria (CENSA), Mayabeque 32700, Cuba
| | - Mariano Domingo
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
- Servei de Diagnòstic de Patologia Veterinària (SDPV), Departament de Sanitat I d’Anatomia Animals, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| | - Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (J.A.B.); (S.M.-G.); (M.P.-S.); (I.M.); (R.R.); (L.C.); (M.D.)
- Correspondence:
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Delogu M, Cotti C, Lelli D, Sozzi E, Trogu T, Lavazza A, Garuti G, Castrucci MR, Vaccari G, De Marco MA, Moreno A. Eco-Virological Preliminary Study of Potentially Emerging Pathogens in Hedgehogs ( Erinaceus europaeus) Recovered at a Wildlife Treatment and Rehabilitation Center in Northern Italy. Animals (Basel) 2020; 10:ani10030407. [PMID: 32121543 PMCID: PMC7143230 DOI: 10.3390/ani10030407] [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: 01/31/2020] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Most of the newly emerging infections arise from animal reservoirs, frequently represented by wildlife species. Western European hedgehogs (Erinaceus europaeus) are mammalian hibernators, mainly nocturnal and insectivorous, living in natural open and green spaces as well as artificial, rural and urban, areas. They are generalist predators of macro-invertebrates, but they may also eat meat, bird eggs and on occasion pet food. These ecological and feeding habits, along with their high population densities, notable synanthropic attitudes, frequent contacts with sympatric wild and domestic species, including humans, implicate the possibility of intra- and interspecies interactions accounting for the possible involvement of E. europaeus in the ecology of several potentially emerging pathogens, including coronaviruses. Using PCR-based and virus isolation methods, we found that 58.3% of 24 hedgehogs’ fecal samples were PCR-positive for Erinaceus coronaviruses (EriCoVs). We did not observe any clinical disease related to the EriCoV infection in hedgehogs. However, the high mutation rates characterizing members of the Coronaviridae family and their potential successful interspecies host jumps—as that likely occurred in the Novel coronavirus (2019-nCoV) emergence—should be considered in the management of hedgehogs admitted to multi-species wildlife rehabilitation centers, recommending their return back to the original recovery areas. Abstract The Western European Hedgehog (Erinaceus europaeus) is one of the four hedgehog species belonging to the genus Erinaceus. Among them, E. amurensis is extant in East Asia’s areas only, whereas E. europaeus, E. roumanicus and E. concolor are mainly found in Europe. E. europaeus is endemically distributed from western to central and southern Europe, including Italy. Western European hedgehogs’ ecological and feeding habits, along with their high population densities, notable synanthropic attitudes, frequent contacts with sympatric wild and domestic species, including humans, implicate the possible involvement of E. europaeus in the ecology of potentially emerging viruses, such as coronaviruses, influenza A and influenza D viruses, canine distemper virus, pestiviruses and Aujeszky’s disease virus. We examined 24 E. europaeus individuals found injured in urban and rural areas of Northern Italy. Of the 24 fecal samples collected and tested for the above-mentioned pathogens by both PCR-based and virus isolation methods, 14 were found PCR-positive for betacoronaviruses belonging to lineage C and related to the known Erinaceus coronaviruses (EriCoVs), as determined by partial sequencing of the virus genome. Our findings suggest that hedgehogs could be considered natural reservoirs of CoVs, and also act as chronic shedding carriers of these potentially emerging RNA viruses.
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Affiliation(s)
- Mauro Delogu
- Department of Veterinary Medical Sciences, University of Bologna, 50 Via Tolara di Sopra, 40064 Ozzano dell’Emilia (BO), Italy; (M.D.); (C.C.); (G.G.)
| | - Claudia Cotti
- Department of Veterinary Medical Sciences, University of Bologna, 50 Via Tolara di Sopra, 40064 Ozzano dell’Emilia (BO), Italy; (M.D.); (C.C.); (G.G.)
| | - Davide Lelli
- Virology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, 7/9 Via Bianchi, 25124 Brescia, Italy; (D.L.); (E.S.); (T.T.); (A.L.); (A.M.)
| | - Enrica Sozzi
- Virology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, 7/9 Via Bianchi, 25124 Brescia, Italy; (D.L.); (E.S.); (T.T.); (A.L.); (A.M.)
| | - Tiziana Trogu
- Virology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, 7/9 Via Bianchi, 25124 Brescia, Italy; (D.L.); (E.S.); (T.T.); (A.L.); (A.M.)
| | - Antonio Lavazza
- Virology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, 7/9 Via Bianchi, 25124 Brescia, Italy; (D.L.); (E.S.); (T.T.); (A.L.); (A.M.)
| | - Giacomo Garuti
- Department of Veterinary Medical Sciences, University of Bologna, 50 Via Tolara di Sopra, 40064 Ozzano dell’Emilia (BO), Italy; (M.D.); (C.C.); (G.G.)
| | - Maria Rita Castrucci
- Department of Infectious Diseases, Istituto Superiore di Sanità, 299 Viale Regina Elena, 00161 Rome, Italy;
| | - Gabriele Vaccari
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, 299 Viale Regina Elena, 00161 Rome, Italy;
| | - Maria Alessandra De Marco
- Wildlife Service, Institute for Environmental Protection and Research (ISPRA), 9 Via Ca’ Fornacetta, 40064 Ozzano dell’Emilia (BO), Italy
- Correspondence: ; Tel.: +39-051-651-2205
| | - Ana Moreno
- Virology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, 7/9 Via Bianchi, 25124 Brescia, Italy; (D.L.); (E.S.); (T.T.); (A.L.); (A.M.)
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A Polyuridine Insertion in the 3' Untranslated Region of Classical Swine Fever Virus Activates Immunity and Reduces Viral Virulence in Piglets. J Virol 2020; 94:JVI.01214-19. [PMID: 31645448 PMCID: PMC6955259 DOI: 10.1128/jvi.01214-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/11/2019] [Indexed: 01/15/2023] Open
Abstract
Classical swine fever (CSF), a highly contagious viral disease of pigs, is still endemic in some countries of Asia and Central and South America. Considering that the 3′ untranslated region (3′ UTR) plays an important role in flavivirus replication, the present study showed for the first time that a long polyuridine sequence acquired in the 3′ UTR by an endemic CSFV isolate can activate immunity, control viral replication, and modulate disease in piglets. Our findings provide new avenues for the development of novel vaccines against infections with CSF virus and other flaviviruses. Knowledge of molecular virulence determinants is also relevant for future development of rapid and efficient diagnostic tools for the prediction of the virulence of field isolates and for efficient CSF control. Low-virulence classical swine fever virus (CSFV) strains make CSF eradication particularly difficult. Few data are available on the molecular determinants of CSFV virulence. The aim of the present study was to assess a possible role for CSFV virulence of a unique, uninterrupted 36-uridine (poly-U) sequence found in the 3′ untranslated region (3′ UTR) of the low-virulence CSFV isolate Pinar de Rio (PdR). To this end, a pair of cDNA-derived viruses based on the PdR backbone were generated, one carrying the long poly-U insertion in the 3′ UTR (vPdR-36U) and the other harboring the standard 5 uridines at this position (vPdR-5U). Two groups of 20 5-day-old piglets were infected with vPdR-36U and vPdR-5U. Ten contact piglets were added to each group. Disease progression, virus replication, and immune responses were monitored for 5 weeks. The vPdR-5U virus was significantly more virulent than the vPdR-36U virus, with more severe disease, higher mortality, and significantly higher viral loads in serum and body secretions, despite similar replication characteristics in cell culture. The two viruses were transmitted to all contact piglets. Ninety percent of the piglets infected with vPdR-36U seroconverted, while only one vPdR-5U-infected piglet developed antibodies. The vPdR-5U-infected piglets showed only transient alpha interferon (IFN-α) responses in serum after 1 week of infection, while the vPdR-36U-infected piglets showed sustained IFN-α levels during the first 2 weeks. Taken together, these data show that the 3′ UTR poly-U insertion acquired by the PdR isolate reduces viral virulence and activates the innate and humoral immune responses without affecting viral transmission. IMPORTANCE Classical swine fever (CSF), a highly contagious viral disease of pigs, is still endemic in some countries of Asia and Central and South America. Considering that the 3′ untranslated region (3′ UTR) plays an important role in flavivirus replication, the present study showed for the first time that a long polyuridine sequence acquired in the 3′ UTR by an endemic CSFV isolate can activate immunity, control viral replication, and modulate disease in piglets. Our findings provide new avenues for the development of novel vaccines against infections with CSF virus and other flaviviruses. Knowledge of molecular virulence determinants is also relevant for future development of rapid and efficient diagnostic tools for the prediction of the virulence of field isolates and for efficient CSF control.
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Abstract
Abstract
Until July 30th, 2019 when the first case of African swine fever (ASF) was confirmed, Serbia was a country free from ASF. After the owner reported atypical illness and death of a sow, the local veterinarian submitted the organ samples to the National Reference Laboratory for Classical Swine Fever (CSF) and African Swine Fever within the Institute of Veterinary Medicine of Serbia in Belgrade. Observed gross lesions included splenomegaly, serous edema of the wall of the gallbladder and hemorrhages in the enlarged portal lymph nodes, petechial hemorrhages on the kidney and epicardium, and petechial and echymotic hemorrhages on the mucosa of the urinary bladder. Results of real-time PCR confirmed that the cause of illness and death of the swine was African swine fever virus. The samples were sent for confirmation to the EU Reference Laboratory where it was confirmed that Serbian domestic pig virus isolates based on p72 belong to genotype II. In total, 270 pigs from 18 affected holdings were killed in the infected zones. According to the on-record data, mortality was 6.89%, whereas lethality reached 64.5%. Currently, an extensive surveillance program is being conducted, aiming to force passive surveillance. ASF in wild boar has not been confirmed so far.
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Vogler BR, Trinkler M, Marti H, Borel N, Pesch T, Prähauser B, Hoop R, Mattmann P, Albini S. Survey on Chlamydiaceae in cloacal swabs from Swiss turkeys demonstrates absence of Chlamydia psittaci and low occurrence of Chlamydia gallinacean. PLoS One 2019; 14:e0226091. [PMID: 31821353 PMCID: PMC6903705 DOI: 10.1371/journal.pone.0226091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 11/19/2019] [Indexed: 11/18/2022] Open
Abstract
In Switzerland, domestic turkey meat is a niche product. Turkeys are fattened on mixed family-based farms scattered across the country, with most providing access to an uncovered outdoor pasture for the birds. Swiss fattening turkeys may therefore get infected with Chlamydiaceae via wild birds or their faeces, potentially shedding these bacteria at a later stage. The aim of the present study was to acquire baseline data about the shedding of Chlamydiaceae in clinically unremarkable Swiss fattening turkeys at slaughter, potentially exposing slaughterhouse workers to infection. In this large-scale study, 1008 cloacal swabs of Swiss turkeys out of 53 flocks from 28 different grow-out farms with uncovered outdoor pasture were collected over the course of 14 months and examined for the occurrence of Chlamydiaceae by a family-specific 23S-rRNA real-time PCR. Positive samples were further analyzed by Chlamydia psittaci (C. psittaci)-specific real-time PCR and the Arraymate DNA Microarray for species identification. All samples were negative for C. psittaci, but seven swabs out of one flock were tested positive for Chlamydia gallinacea (0.7%). Although turkeys with access to pasture may have contact with Chlamydiaceae-harbouring wild birds or their faeces, the infection rate in Swiss turkeys was shown to be low.
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Affiliation(s)
- Barbara Renate Vogler
- National Reference Centre for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Michal Trinkler
- National Reference Centre for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Hanna Marti
- Institute for Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Nicole Borel
- Institute for Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Theresa Pesch
- Institute for Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Barbara Prähauser
- Institute for Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Richard Hoop
- National Reference Centre for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Prisca Mattmann
- National Reference Centre for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Sarah Albini
- National Reference Centre for Poultry and Rabbit Diseases (NRGK), Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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