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Kolla HB, Dutt M, Kumar A, Hebbandi Nanjunadappa R, Karakach T, Singh KP, Kelvin D, Clement Mertens PP, Umeshappa CS. Immuno-informatics study identifies conserved T cell epitopes in non-structural proteins of Bluetongue virus serotypes: formulation of a computationally optimized next-generation broad-spectrum multi-epitope vaccine. Front Immunol 2024; 15:1424307. [PMID: 39011043 PMCID: PMC11246920 DOI: 10.3389/fimmu.2024.1424307] [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: 04/27/2024] [Accepted: 06/13/2024] [Indexed: 07/17/2024] Open
Abstract
Introduction Bluetongue (BT) poses a significant threat to the livestock industry, affecting various animal species and resulting in substantial economic losses. The existence of numerous BT virus (BTV) serotypes has hindered control efforts, highlighting the need for broad-spectrum vaccines. Methodology In this study, we evaluated the conserved amino acid sequences within key non-structural (NS) proteins of BTV and identified numerous highly conserved murine- and bovine-specific MHC class I-restricted (MHC-I) CD8+ and MHC-II-restricted CD4+ epitopes. We then screened these conserved epitopes for antigenicity, allergenicity, toxicity, and solubility. Using these epitopes, we developed in silico-based broad-spectrum multiepitope vaccines with Toll-like receptor (TLR-4) agonists. The predicted proinflammatory cytokine response was assessed in silico using the C-IMMSIM server. Structural modeling and refinement were achieved using Robetta and GalaxyWEB servers. Finally, we assessed the stability of the docking complexes through extensive 100-nanosecond molecular dynamics simulations before considering the vaccines for codon optimization and in silico cloning. Results We found many epitopes that meet these criteria within NS1 and NS2 proteins and developed in silico broad-spectrum vaccines. The immune simulation studies revealed that these vaccines induce high levels of IFN-γ and IL-2 in the vaccinated groups. Protein-protein docking analysis demonstrated promising epitopes with strong binding affinities to TLR-4. The docked complexes were stable, with minimal Root Mean Square Deviation and Root Mean Square Fluctuation values. Finally, the in silico-cloned plasmids have high % of GC content with > 0.8 codon adaptation index, suggesting they are suitable for expressing the protein vaccines in prokaryotic system. Discussion These next-generation vaccine designs are promising and warrant further investigation in wet lab experiments to assess their immunogenicity, safety, and efficacy for practical application in livestock. Our findings offer a robust framework for developing a comprehensive, broad-spectrum vaccine, potentially revolutionizing BT control and prevention strategies in the livestock industry.
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Affiliation(s)
- Harish Babu Kolla
- Department of Microbiology, Immunology and Pediatrics, Dalhousie University, Halifax, NS, Canada
- Immunology Division, IWK Health Centre, Halifax, NS, Canada
| | - Mansi Dutt
- Department of Microbiology, Immunology and Pediatrics, Dalhousie University, Halifax, NS, Canada
- Immunology Division, IWK Health Centre, Halifax, NS, Canada
| | - Anuj Kumar
- Department of Microbiology, Immunology and Pediatrics, Dalhousie University, Halifax, NS, Canada
- Immunology Division, IWK Health Centre, Halifax, NS, Canada
| | - Roopa Hebbandi Nanjunadappa
- Department of Microbiology, Immunology and Pediatrics, Dalhousie University, Halifax, NS, Canada
- Immunology Division, IWK Health Centre, Halifax, NS, Canada
| | - Tobias Karakach
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada
| | - Karam Pal Singh
- Center for Animal Disease Research and Diagnosis, Indian Veterinary Research Institute, Bareilly, India
| | - David Kelvin
- Department of Microbiology, Immunology and Pediatrics, Dalhousie University, Halifax, NS, Canada
- Immunology Division, IWK Health Centre, Halifax, NS, Canada
| | | | - Channakeshava Sokke Umeshappa
- Department of Microbiology, Immunology and Pediatrics, Dalhousie University, Halifax, NS, Canada
- Immunology Division, IWK Health Centre, Halifax, NS, Canada
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Gwynn A, Mbewana S, Lubisi BA, Tshabalala HM, Rybicki EP, Meyers AE. Chimaeric plant-produced bluetongue virus particles as potential vaccine candidates. Arch Virol 2023; 168:179. [PMID: 37310539 DOI: 10.1007/s00705-023-05790-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 04/29/2023] [Indexed: 06/14/2023]
Abstract
Bluetongue virus (BTV) causes bluetongue disease in ruminants and sheep. The current live attenuated and inactivated vaccines available for prevention pose several risks, and there is thus a need for vaccines that are safer, economically viable, and effective against multiple circulating serotypes. This work describes the development of recombinant virus-like particle (VLP) vaccine candidates in plants, which are assembled by co-expression of the four BTV serotype 8 major structural proteins. We show that substitution of a neutralising tip domain of BTV8 VP2 with that of BTV1 VP2 resulted in the assembly of VLPs that stimulated serotype-specific antibodies as well as virus-specific neutralising antibodies.
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Affiliation(s)
- A Gwynn
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7700, South Africa
| | - S Mbewana
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7700, South Africa
| | - B A Lubisi
- Diagnostic Services Programme, ARC-Onderstepoort Veterinary Research Institute, Pretoria, 0110, South Africa
| | - H M Tshabalala
- Diagnostic Services Programme, ARC-Onderstepoort Veterinary Research Institute, Pretoria, 0110, South Africa
| | - E P Rybicki
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7700, South Africa
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Observatory, CapeTown, 7925, South Africa
| | - A E Meyers
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7700, South Africa.
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Bréard E, Turpaud M, Beaud G, Postic L, Fablet A, Beer M, Sailleau C, Caignard G, Viarouge C, Hoffmann B, Vitour D, Zientara S. Development and Validation of an ELISA for the Detection of Bluetongue Virus Serotype 4-Specific Antibodies. Viruses 2021; 13:v13091741. [PMID: 34578322 PMCID: PMC8473233 DOI: 10.3390/v13091741] [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: 07/29/2021] [Revised: 08/21/2021] [Accepted: 08/24/2021] [Indexed: 12/14/2022] Open
Abstract
In this article, we describe the development and evaluation of a double antigen sandwich enzyme-linked immunosorbent assay (ELISA) able to detect serotype 4-specific antibodies from BTV-4 infected or vaccinated animals using a recombinant BTV-4 VP2 protein. The coding sequence of VP2 was inserted into a pVote plasmid by recombination in the Gateway® cloning system. Vaccinia virus (VacV) was used as a vector for the expression of the recombinant VP2. After production in BSR cells, recombinant VP2 was purified by immunoprecipitation using a FLAG tag and then used both as the coated ELISA antigen and as the HRP-tagged conjugate. The performance of the ELISA was evaluated with 1186 samples collected from BTV negative, infected or vaccinated animals. The specificity and sensitivity of the BTV-4 ELISA were above the expected standards for the detection of anti-BTV-4 VP2 antibodies in animals reared in Europe or in the Mediterranean basin. Cross-reactions were observed with reference sera for serotypes 10 and 20, and to a lesser extent with serotypes 12, 17 and 24, due to their genetic proximity to serotype 4. Nevertheless, these serotypes have never been detected in Europe and the Mediterranean area. This ELISA, which requires only the production of a recombinant protein, can be used to detect BTV serotype 4-specific antibodies and is therefore an attractive alternative diagnostic method to serum neutralization.
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Affiliation(s)
- Emmanuel Bréard
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
- Correspondence:
| | - Mathilde Turpaud
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Georges Beaud
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Lydie Postic
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Aurore Fablet
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany; (M.B.); (B.H.)
| | - Corinne Sailleau
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Grégory Caignard
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Cyril Viarouge
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Bernd Hoffmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany; (M.B.); (B.H.)
| | - Damien Vitour
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
| | - Stéphan Zientara
- UMR 1161 Virologie, Laboratory for Animal Health, INRAE, Department of Animal Health, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, 94700 Maisons-Alfort, France; (M.T.); (G.B.); (L.P.); (A.F.); (C.S.); (G.C.); (C.V.); (D.V.); (S.Z.)
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van Rijn PA. Prospects of Next-Generation Vaccines for Bluetongue. Front Vet Sci 2019; 6:407. [PMID: 31824966 PMCID: PMC6881303 DOI: 10.3389/fvets.2019.00407] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 11/01/2019] [Indexed: 01/16/2023] Open
Abstract
Bluetongue (BT) is a haemorrhagic disease of wild and domestic ruminants with a huge economic worldwide impact on livestock. The disease is caused by BT-virus transmitted by Culicoides biting midges and disease control without vaccination is hardly possible. Vaccination is the most feasible and cost-effective way to minimize economic losses. Marketed BT vaccines are successfully used in different parts of the world. Inactivated BT vaccines are efficacious and safe but relatively expensive, whereas live-attenuated vaccines are efficacious and cheap but are unsafe because of under-attenuation, onward spread, reversion to virulence, and reassortment events. Both manufactured BT vaccines do not enable differentiating infected from vaccinated animals (DIVA) and protection is limited to the respective serotype. The ideal BT vaccine is a licensed, affordable, completely safe DIVA vaccine, that induces quick, lifelong, broad protection in all susceptible ruminant species. Promising vaccine candidates show improvement for one or more of these main vaccine standards. BTV protein vaccines and viral vector vaccines have DIVA potential depending on the selected BTV antigens, but are less effective and likely more costly per protected animal than current vaccines. Several vaccine platforms based on replicating BTV are applied for many serotypes by exchange of serotype dominant outer shell proteins. These platforms based on one BTV backbone result in attenuation or abortive virus replication and prevent disease by and spread of vaccine virus as well as reversion to virulence. These replicating BT vaccines induce humoral and T-cell mediated immune responses to all viral proteins except to one, which could enable DIVA tests. Most of these replicating vaccines can be produced similarly as currently marketed BT vaccines. All replicating vaccine platforms developed by reverse genetics are classified as genetic modified organisms. This implies extensive and expensive safety trails in target ruminant species, and acceptance by the community could be hindered. Nonetheless, several experimental BT vaccines show very promising improvements and could compete with marketed vaccines regarding their vaccine profile, but none of these next generation BT vaccines have been licensed yet.
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Affiliation(s)
- Piet A van Rijn
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, Netherlands.,Department of Biochemistry, Centre for Human Metabolomics, North-West University, Potchefstroom, South Africa
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Ries C, Beer M, Hoffmann B. BTV antibody longevity in cattle five to eight years post BTV-8 vaccination. Vaccine 2019; 37:2656-2660. [PMID: 30979569 DOI: 10.1016/j.vaccine.2019.03.082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/28/2019] [Accepted: 03/31/2019] [Indexed: 01/21/2023]
Abstract
The Bluetongue virus serotype -8 (BTV-8) epizootic in Germany (2006-2008) was successfully eradicated, essentially by the massive application of commercially available inactivated BTV-8 vaccines. While a six-year antibody longevity of BTV antibodies post BTV-8 vaccination in cattle has been described previously, our study investigated the BTV-8-vaccine antibodies in cattle for up to eight years. In total, 157 bovine serum samples were analysed for the presence of group-specific BTV antibodies in both a commercial cELISA, and a BTV-8- specific serum neutralization test. A robust number of cattle were seropositive for group- and serotype-specific neutralising antibodies for five or more years. In selected animals, born and vaccinated in 2009 or later, the presence of BTV antibodies for up to eight years post BTV-8 vaccination could be confirmed. Our data also show, that booster vaccination prolonged the antibody longevity of vaccine-induced antibodies and the number of serologically positive cattle.
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Affiliation(s)
- Christina Ries
- Friedrich-Loeffler-Institut, Institute of Diagnostic Virology, Südufer 10, 17943 Greifswald - Insel Riems, Germany
| | - Martin Beer
- Friedrich-Loeffler-Institut, Institute of Diagnostic Virology, Südufer 10, 17943 Greifswald - Insel Riems, Germany
| | - Bernd Hoffmann
- Friedrich-Loeffler-Institut, Institute of Diagnostic Virology, Südufer 10, 17943 Greifswald - Insel Riems, Germany.
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Beta-propiolactone inactivated bivalent bluetongue virus vaccine containing Montanide ISA-71VG adjuvant induces long-term immune response in sheep against serotypes 4 and 16 even after 3 years of controlled vaccine storage. Vet Microbiol 2018; 226:23-30. [PMID: 30389040 DOI: 10.1016/j.vetmic.2018.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 09/18/2018] [Accepted: 10/10/2018] [Indexed: 01/27/2023]
Abstract
In this study, we developed and evaluated the beta-propiolactone inactivated bivalent bluetongue virus (BTV) serotypes 4 and 16 vaccine delivered with Montanide™ ISA-71VG adjuvant. The safety, stability and immunological profile of the fresh and after three years of long-term storage of the vaccine formulation was analyzed. We observed after long-term storage that the vaccine emulsion was stable as indicated by unchanged pH and viscosity. The stored vaccine formulation induced virus neutralizing antibodies (VNA) in sheep against both the bluetongue virus serotypes at 7-10 day post-vaccination (dpv). VNA titers reached the peak by 60 dpv and detectable during the entire study period. Antibodies against bluetongue virus structural protein VP7 were detected by ELISA in all BTV vaccinated experimental animal groups. Partial clinical protection was observed in vaccinates against challenge virulent BTV-4 and BTV-16 serotypes by 10 dpv, while complete protection was observed at 14 dpv. The levels of viremia was decreased in challenged sheep by 10 dpv while the viremia was undetectable by 14 dpv. In summary, our newly formulated bivalent BTV (BTV-4 and BTV-16) vaccine delivered with Montanide™ ISA-71VG adjuvant was found safe and stable for over three years and induced protective response in sheep.
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7
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Ayrle H, Mevissen M, Kaske M, Vögtlin A, Fricker R, Hoffmann B, Büttner M, Marinovic Z, Walkenhorst M. Colostral transmission of BTV-8 antibodies from dairy cows six years after vaccination. Vaccine 2018; 36:5807-5810. [DOI: 10.1016/j.vaccine.2018.08.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/27/2018] [Accepted: 08/05/2018] [Indexed: 10/28/2022]
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Martinelle L, Dal Pozzo F, Thys C, De Leeuw I, Van Campe W, De Clercq K, Thiry E, Saegerman C. Assessment of cross-protection induced by a bluetongue virus (BTV) serotype 8 vaccine towards other BTV serotypes in experimental conditions. Vet Res 2018; 49:63. [PMID: 30012223 PMCID: PMC6048908 DOI: 10.1186/s13567-018-0556-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 06/25/2018] [Indexed: 02/06/2023] Open
Abstract
Bluetongue disease is caused by bluetongue virus (BTV) and BTV serotype 8 (BTV8) caused great economic damage in Europe during the last decade. From 1998 to 2007, in addition to BTV8, Europe had to face the emergence of BTV1, 2, 4, 9, and 16, spreading in countries where the virus has never been detected before. These unprecedented outbreaks trigger the need to evaluate and compare the clinical, virological and serological features of the European BTV serotypes in the local epidemiological context. In this study groups of calves were infected with one of the following European BTV serotypes, namely BTV1, 2, 4, 9 and 16. For each tested serotype, two groups of three male Holstein calves were used: one group vaccinated against BTV8, the other non-vaccinated. Clinical signs were quantified, viral RNA was detected in blood and organs and serological relationship was assessed. Calves were euthanized 35 days post-infection and necropsied. Most of the infected animals showed mild clinical signs. A partial serological cross reactivity has been reported between BTV8 and BTV4, and between BTV1 and BTV8. BTV2 and BTV4 viral RNA only reached low levels in blood, when compared to other serotypes, whereas in vitro growth assays could not highlight significant differences. Altogether the results of this study support the hypothesis of higher adaptation of some BTV strains to specific hosts, in this case calves. Furthermore, cross-protection resulting from a prior vaccination with BTV8 was highlighted based on cross-neutralization. However, the development of neutralizing antibodies is probably not totally explaining the mild protection induced by the heterologous vaccination.
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Affiliation(s)
- Ludovic Martinelle
- Faculty of Veterinary Medicine, Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Fundamental and Applied Research for Animal and Health (FARAH) Center, University of Liege, Liege, Belgium
| | - Fabiana Dal Pozzo
- Faculty of Veterinary Medicine, Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Fundamental and Applied Research for Animal and Health (FARAH) Center, University of Liege, Liege, Belgium
| | - Christine Thys
- Faculty of Veterinary Medicine, Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Fundamental and Applied Research for Animal and Health (FARAH) Center, University of Liege, Liege, Belgium
| | | | | | | | - Etienne Thiry
- Faculty of Veterinary Medicine, Fundamental and Applied Research for Animal and Health (FARAH) Center, Veterinary Virology and Animal Viral Diseases, University of Liege, Liege, Belgium
| | - Claude Saegerman
- Faculty of Veterinary Medicine, Research Unit in Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Fundamental and Applied Research for Animal and Health (FARAH) Center, University of Liege, Liege, Belgium.
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Bournez L, Cavalerie L, Sailleau C, Bréard E, Zanella G, Servan de Almeida R, Pedarrieu A, Garin E, Tourette I, Dion F, Hendrikx P, Calavas D. Estimation of French cattle herd immunity against bluetongue serotype 8 at the time of its re-emergence in 2015. BMC Vet Res 2018; 14:65. [PMID: 29499711 PMCID: PMC5834897 DOI: 10.1186/s12917-018-1388-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 02/21/2018] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND From 2006 to 2010, France experienced two bluetongue epidemics caused by serotype 1 (BTV-1) and 8 (BTV-8) which were controlled by mass vaccination campaigns. After five years without any detected cases, a sick ram was confirmed in August 2015 to be infected by a BTV-8 strain almost identical to that circulating during the previous outbreak. By then, part of the French cattle population was expected to be still protected, since bluetongue antibodies are known to last for many years after natural infection or vaccination. The objective of this study was to estimate the proportion of cattle in France still immune to BTV-8 at the time of its re-emergence in 2015. RESULTS We used BTV group-specific cELISA results from 8525 cattle born before the vaccination ban in 2013 and 15,799 cattle born after the ban. Samples were collected from January to April 2016 to estimate seroprevalence per birth cohort. The overall seroprevalence in cattle at national and local levels was extrapolated from seroprevalence results per birth cohort and their respective proportion at each level. To indirectly assess pre-immune status of birth cohorts, we computed prevalence per birth cohort on infected farms in autumn 2015 using 1377 RT-PCR results. These revealed limited BTV circulation in 2015. Seroprevalence per birth cohort was likely to be connected to past exposure to natural infection and/or vaccination with higher seroprevalence levels in older animals. A seroprevalence of 95% was observed for animals born before 2008, of which > 90% were exposed to two compulsory vaccination campaigns in 2008-2010. None of the animals born before 2008 were found to be infected, unlike 19% of the young cattle which had never been vaccinated. This suggests that most ELISA-positive animals were pre-immune to BTV-8. We estimated that 18% (from 12% to 32% per département) of the French cattle population was probably pre-immune in 2015. CONCLUSIONS These results strongly suggest a persistence of antibodies for at least 5-6 years after natural infection or vaccination. The herd immunity of the French cattle population probably limited BTV circulation up to 2015, by which time more than 80% of cattle were naive.
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Affiliation(s)
- L Bournez
- ANSES (French Agency for Food, Environmental and Occupational Health & Safety), Unité de coordination et d'appui à la surveillance, Direction des laboratoires, Maisons Alfort, France.
| | - L Cavalerie
- Ministère en charge de l'Agriculture, Direction générale de l'Alimentation, Bureau de la santé animale, Paris, France
| | - C Sailleau
- ANSES, Laboratoire de santé animale, Université Paris-Est, Maisons-Alfort, France
| | - E Bréard
- ANSES, Laboratoire de santé animale, Université Paris-Est, Maisons-Alfort, France
| | - G Zanella
- ANSES, Laboratoire de santé animale, Université Paris-Est, Maisons-Alfort, France
| | | | - A Pedarrieu
- CIRAD, UMR ASTRE, Montpellier ; Inra, UMR ASTRE, Montpellier, France
| | - E Garin
- Coop de France, Paris, France
| | | | - F Dion
- Races de France, Paris, France
| | - P Hendrikx
- ANSES (French Agency for Food, Environmental and Occupational Health & Safety), Unité de coordination et d'appui à la surveillance, Direction des laboratoires, Maisons Alfort, France
| | - D Calavas
- ANSES, Laboratoire de Lyon, Unité Epidémiologie, Laboratoire de Lyon, Lyon, France
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More S, Bicout D, Bøtner A, Butterworth A, Depner K, Edwards S, Garin-Bastuji B, Good M, Gortázar Schmidt C, Michel V, Miranda MA, Nielsen SS, Raj M, Sihvonen L, Spoolder H, Stegeman JA, Thulke HH, Velarde A, Willeberg P, Winckler C, Mertens P, Savini G, Zientara S, Broglia A, Baldinelli F, Gogin A, Kohnle L, Calistri P. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): bluetongue. EFSA J 2017; 15:e04957. [PMID: 32625623 PMCID: PMC7010010 DOI: 10.2903/j.efsa.2017.4957] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
A specific concept of strain was developed in order to classify the BTV serotypes ever reported in Europe based on their properties of animal health impact: the genotype, morbidity, mortality, speed of spread, period and geographical area of occurrence were considered as classification parameters. According to this methodology the strain groups identified were (i) the BTV strains belonging to serotypes BTV-1-24, (ii) some strains of serotypes BTV-16 and (iii) small ruminant-adapted strains belonging to serotypes BTV-25, -27, -30. Those strain groups were assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7, Article 5 on the eligibility of bluetongue to be listed, Article 9 for the categorisation according to disease prevention and control rules as in Annex IV and Article 8 on the list of animal species related to bluetongue. The assessment has been performed following a methodology composed of information collection, expert judgement at individual and collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. The strain group BTV (1-24) can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL, while the strain group BTV-25-30 and BTV-16 cannot. The strain group BTV-1-24 meets the criteria as in Sections 2 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (b) and (e) of Article 9(1) of the AHL. The animal species that can be considered to be listed for BTV-1-24 according to Article 8(3) are several species of Bovidae, Cervidae and Camelidae as susceptible species; domestic cattle, sheep and red deer as reservoir hosts, midges insect of genus Culicoides spp. as vector species.
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Feenstra F, van Rijn PA. Current and next-generation bluetongue vaccines: Requirements, strategies, and prospects for different field situations. Crit Rev Microbiol 2016; 43:142-155. [PMID: 27800699 DOI: 10.1080/1040841x.2016.1186005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Bluetongue virus (BTV) causes the hemorrhagic disease bluetongue (BT) in ruminants. The best way to control outbreaks is vaccination. Currently, conventionally modified-live and inactivated vaccines are commercially available, which have been successfully used to control BT, but nonetheless have their specific shortcomings. Therefore, there is a need for improved BT vaccines. The ideal BT vaccine is efficacious, safe, affordable, protective against multiple serotypes and enables the differentiation of infected from vaccinated animals. Different field situations require specific vaccine profiles. Single serotype outbreaks in former BT-free areas need rapid onset of protection against viremia of the respective serotype. In contrary, endemic multiple serotype situations require long-lasting protection against all circulating serotypes. The ideal BT vaccine for all field situations does not exist and balancing between vaccine properties is needed. Many new vaccines candidates, ranging from non-replicating subunits to replicating next-generation reverse genetics based vaccines, have been developed. Some have been tested extensively in large numbers of ruminants, whereas others were developed recently and have only been tested in vitro and in mice models. Most vaccine candidates are promising, but have their specific shortcomings and advantages. In this review, current and next-generation BT vaccines are discussed in the light of prerequisites for different field situations.
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Affiliation(s)
- Femke Feenstra
- a Department of Virology , Central Veterinary Institute of Wageningen UR , Lelystad , The Netherlands.,b Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine , Utrecht University , Utrecht , The Netherlands
| | - Piet A van Rijn
- a Department of Virology , Central Veterinary Institute of Wageningen UR , Lelystad , The Netherlands.,c Department of Biochemistry , Center for Human Metabolomics, North-West University , Potchefstroom , South Africa
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12
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Martinelle L, Dal Pozzo F, Sarradin P, Van Campe W, De Leeuw I, De Clercq K, Thys C, Thiry E, Saegerman C. Experimental bluetongue virus superinfection in calves previously immunized with bluetongue virus serotype 8. Vet Res 2016; 47:73. [PMID: 27465686 PMCID: PMC4964278 DOI: 10.1186/s13567-016-0357-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 06/28/2016] [Indexed: 11/10/2022] Open
Abstract
The effect of a superinfection with bluetongue virus serotype 1 (BTV1) was evaluated on two groups of four calves. One group received a commercial inactivated BTV serotype 8 (BTV8) vaccine. This group and the non-vaccinated group of calves were challenged twice (4 months apart) with the European BTV8 strain isolated during the 2006–2007 epidemics. Calves were then infected with a BTV1 inoculum which was found to be unexpectedly contaminated by BTV serotype 15 (BTV15). BTV1 and BTV15 single infections were performed on two other groups of three BTV naïve calves. A severe clinical picture was obtained after superinfection with BTV1/BTV15 in both vaccinated and non-vaccinated animals and after challenge with BTV8 in non-vaccinated animals. BTV1 and BTV15 single infection caused only very slight clinical signs. After superinfection and at the viraemic peak, there were an average of above 1000 times more BTV15 genomic copies than BTV1 ones. BTV1 RNA could be detected only in the spleen of one calf whereas BTV15 RNA was found in 15 organs of seven different animals. BTV8 immunization whether it was acquired through vaccination and challenges or challenges alone did not change BTV1 or BTV15 RNA detection in superinfected animals. However in these animals a partial cross neutralization between BTV8 and BTV1 might be involved in the lower BTV1 replication versus BTV15. Infection with different serotypes can occur also in the field. Interference between virus strains, genetic reassortment and cross-protection were considered as mechanisms to explain the clinical outcomes and the other virological and immunological findings in the course of BTV1/BTV15 superinfection.
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Affiliation(s)
- Ludovic Martinelle
- Research Unit in Epidemiology and Risk Analysis Applied to the Veterinary Sciences (UREAR-ULg), Department of Infectious and Parasitic Diseases, Center for Fundamental and Applied Research for Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Quartier Vallée 2, Avenue de Cureghem 7A, B42, 4000, Liège, Belgium
| | - Fabiana Dal Pozzo
- Research Unit in Epidemiology and Risk Analysis Applied to the Veterinary Sciences (UREAR-ULg), Department of Infectious and Parasitic Diseases, Center for Fundamental and Applied Research for Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Quartier Vallée 2, Avenue de Cureghem 7A, B42, 4000, Liège, Belgium
| | - Pierre Sarradin
- INRA, UE 1277, Experimental Infectiology Platform, INRA-Research Centre of Tours, Nouzilly, France
| | - Willem Van Campe
- Animal Experimental Centre, CODA-CERVA, Kerklaan 68, 1830, Machelen, Belgium
| | - Ilse De Leeuw
- Unit Vesicular and Exotic Diseases, CODA-CERVA, Groeselenberg 99, Uccle, 1180, Brussels, Belgium
| | - Kris De Clercq
- Unit Vesicular and Exotic Diseases, CODA-CERVA, Groeselenberg 99, Uccle, 1180, Brussels, Belgium
| | - Christine Thys
- Research Unit in Epidemiology and Risk Analysis Applied to the Veterinary Sciences (UREAR-ULg), Department of Infectious and Parasitic Diseases, Center for Fundamental and Applied Research for Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Quartier Vallée 2, Avenue de Cureghem 7A, B42, 4000, Liège, Belgium
| | - Etienne Thiry
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Center for Fundamental and Applied Research for Animal and Health (FARAH), University of Liege, Quartier Vallée 2, Avenue de Cureghem 10, B43bis, 4000, Liège, Belgium
| | - Claude Saegerman
- Research Unit in Epidemiology and Risk Analysis Applied to the Veterinary Sciences (UREAR-ULg), Department of Infectious and Parasitic Diseases, Center for Fundamental and Applied Research for Animal and Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Quartier Vallée 2, Avenue de Cureghem 7A, B42, 4000, Liège, Belgium.
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13
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McVey DS, MacLachlan NJ. Vaccines for Prevention of Bluetongue and Epizootic Hemorrhagic Disease in Livestock: A North American Perspective. Vector Borne Zoonotic Dis 2016; 15:385-96. [PMID: 26086559 DOI: 10.1089/vbz.2014.1698] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bluetongue (BT) and epizootic hemorrhagic disease (EHD) are noncontagious, insect-transmitted diseases of domestic and wild ruminants caused by related but distinct viruses. There are significant gaps in our scientific knowledge and available countermeasures to control an outbreak of orbivirus-induced disease, whether BT or EHD. Both BT virus (BTV) and EHD virus (EHDV) cause hemorrhagic fevers in susceptible ruminants; however, BT is principally a disease of domestic livestock whereas EHD is principally a disease of certain species of wild, non-African ungulates, notably white-tailed deer. The live-attenuated (modified live virus [MLV]) vaccines available in the United States for use in small ruminant livestock do provide good protection against clinical disease following infection with the homologous virus serotype. Although there is increasing justification that the use of MLV vaccines should be avoided if possible, these are the only vaccines currently available in the United States. Specifically, MLVs are used in California to protect sheep against infection with BTV serotypes 10, 11, and 17, and a MLV to BTV serotype 10 is licensed for use in sheep throughout the United States. These MLV vaccines may need to continue to be used in the immediate future for protective immunization of sheep and goats against BT. There are currently no licensed vaccines available for EHD in the United States other than autogenous vaccines. If there is a need to rapidly develop a vaccine to meet an emerging crisis associated with either BTV or EHDV infections, development of an inactivated virus vaccine in a conventional adjuvanted formulation will likely be required. With two doses of vaccine (and in some instances just one dose), inactivated vaccines can provide substantial immunity to the epizootic serotype of either BTV or EHDV. This strategy is similar to that used in the 2006-2008 BTV serotype 8 outbreaks in northern Europe that provided vaccine to the field within 2 years of the initial incursion (by 2008). Further research and development are warranted to provide more efficacious and effective vaccines for control of BTV and EHDV infections.
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Affiliation(s)
- D Scott McVey
- 1 USDA, ARS , Arthropod-Borne Animal Disease Research Unit, Center for Grain and Animal Health Research, Manhattan, Kansas
| | - N James MacLachlan
- 2 Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California , Davis, California
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Mulholland C, Hoffmann B, McMenamy MJ, Korthase C, Earley B, Markey B, Cassidy JP, McKillen J, Allan G, Welsh MD. The development of an accelerated reverse-transcription loop mediated isothermal amplification for the serotype specific detection of bluetongue virus 8 in clinical samples. J Virol Methods 2014; 202:95-100. [PMID: 24642243 DOI: 10.1016/j.jviromet.2014.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 03/04/2014] [Accepted: 03/07/2014] [Indexed: 11/26/2022]
Abstract
In 2006 bluetongue virus serotype 8 (BTV 8) was identified for the first time in the Netherlands causing a major epidemic in sheep and cattle that quickly spread to neighbouring Belgium, Germany and beyond to France and the UK. This resulted in severe animal health and welfare problems as well as substantial economic losses to the agrifood industries of these countries. Given that the early diagnosis of BTV infection 'in-the-field' is extremely useful to its subsequent management and control, this study was established to design a novel, sensitive and rapid nucleic acid diagnostic test for the serotype-specific detection of BTV 8, which could be used without the use of advanced laboratory support and equipment. Primers for the detection of BTV 8 were based on genome segment 2 of the virus, the VP2 gene. The assay was assessed using a full panel of BTV reference strains and clinical samples. Positive amplification was observed using a fluorescent detection reagent. The sensitivity of the RT-LAMP assay was 102 copies of RNA. The assay did not amplify the closely related orbivirus EHDV. This novel RT-LAMP offers a sensitive, specific and rapid method of detecting BTV 8. The approach is inexpensive and easy to use and could potentially be used in a 'pen-side' setting 'in the field' or by smaller less well-equipped laboratories in developing countries.
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Affiliation(s)
- Catherine Mulholland
- Agri Food Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast BT4 3SD, UK; Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Dunsany, Co. Meath, Ireland; School of Veterinary Medicine, Veterinary Sciences Centre, University College Dublin, Belfield, Ireland.
| | - Bernd Hoffmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Michael J McMenamy
- Agri Food Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast BT4 3SD, UK
| | - Christian Korthase
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Bernadette Earley
- Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Dunsany, Co. Meath, Ireland
| | - Bryan Markey
- School of Veterinary Medicine, Veterinary Sciences Centre, University College Dublin, Belfield, Ireland
| | - Joseph P Cassidy
- School of Veterinary Medicine, Veterinary Sciences Centre, University College Dublin, Belfield, Ireland
| | - John McKillen
- Agri Food Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast BT4 3SD, UK
| | - Gordon Allan
- Agri Food Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast BT4 3SD, UK
| | - Michael D Welsh
- Agri Food Biosciences Institute, Veterinary Sciences Division, Stoney Road, Stormont, Belfast BT4 3SD, UK
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Martinelle L, Dal Pozzo F, Sarradin P, De Leeuw I, De Clercq K, Thys C, Thiry E, Saegerman C. Pulmonary artery haemorrhage in newborn calves following bluetongue virus serotype 8 experimental infections of pregnant heifers. Vet Microbiol 2013; 167:250-9. [PMID: 24035481 DOI: 10.1016/j.vetmic.2013.08.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 08/13/2013] [Accepted: 08/19/2013] [Indexed: 11/18/2022]
Abstract
The emergence of bluetongue disease (BT) among livestock in Europe in 2006 raised many questions including the occurrence and epidemiological significance of foetal infections in cattle. To clarify these aspects, vaccinated and unvaccinated pregnant heifers were sequentially infected twice in an isolation facility (biosafety level 3) with a northern European outbreak strain of Bluetongue virus serotype 8 (BTV-8). The study was terminated 2 months after calving with necropsy of the dams and their offspring. The cattle were monitored throughout the study by clinical scoring and for the presence of circulating neutralising antibodies, and after calving for the presence of infectious virus and viral RNA in blood and milk. Four calves, one born from a vaccinated dam and three from non-vaccinated ones, that were infected at 120 days of gestation had obvious haemorrhage of the pulmonary artery at necropsy. Although haemorrhage of the pulmonary artery is highly characteristic of BT, viral RNA was not detected in any of these calves. Furthermore, although none of the calves born from heifers infected prior to mid-gestation had teratogenic BTV typical brain lesions, some had lesions at birth suggestive of in utero BTV infection. Despite the lack of viral RNA detection, the presence of haemorrhage of the pulmonary artery deserves to be reported as a new observation in the context of the multiple investigations having as main subject the BTV placental crossing in cattle.
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Affiliation(s)
- Ludovic Martinelle
- Research Unit of Epidemiology and Risk Analysis Applied to the Veterinary Sciences (UREAR-ULg), Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Boulevard de Colonster 20, B-4000 Liège, Belgium
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16
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Zanella G, Bréard E, Sailleau C, Zientara S, Viarouge C, Durand B. A one-year follow-up of antibody response in cattle and sheep after vaccination with serotype 8- and serotype 1-inactivated BT vaccines. Transbound Emerg Dis 2013; 61:473-6. [PMID: 23331382 DOI: 10.1111/tbed.12048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Indexed: 11/30/2022]
Abstract
Sixteen sheep and 18 cattle were followed up during 1 year to estimate the duration of immunity induced by inactivated bluetongue virus serotype 8 (BTV-8) vaccines (sheep and cattle) and a bluetongue virus serotype 1 (BTV-1) vaccine (cattle) under field conditions using cELISA and seroneutralization test (SNT). Four sheep never seroconverted. Those that seroconverted were all seronegative by BTV-8 SNT at the date of last sampling [378 days post-vaccination (dpv)]. Eight sheep were still positive by competitive ELISA (cELISA) 378 dpv. All the cattle seroconverted. At the end of the study, eight and 11 cattle were still positive by BTV-8 SNT and cELISA, respectively (335 dpv); and nine were still positive by BTV-1 SNT (301 dpv).
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Affiliation(s)
- G Zanella
- ANSES, Epidemiology Unit, Animal Health Laboratory, Maisons-Alfort, France
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Lorca-Oró C, Pujols J, García-Bocanegra I, Mentaberre G, Granados JE, Solanes D, Fandos P, Galindo I, Domingo M, Lavín S, López-Olvera JR. Protection of Spanish Ibex (Capra pyrenaica) against Bluetongue virus serotypes 1 and 8 in a subclinical experimental infection. PLoS One 2012; 7:e36380. [PMID: 22666321 PMCID: PMC3364256 DOI: 10.1371/journal.pone.0036380] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 04/03/2012] [Indexed: 12/26/2022] Open
Abstract
Many wild ruminants such as Spanish ibex (Capra pyrenaica) are susceptible to Bluetongue virus (BTV) infection, which causes disease mainly in domestic sheep and cattle. Outbreaks involving either BTV serotypes 1 (BTV-1) and 8 (BTV-8) are currently challenging Europe. Inclusion of wildlife vaccination among BTV control measures should be considered in certain species. In the present study, four out of fifteen seronegative Spanish ibexes were immunized with a single dose of inactivated vaccine against BTV-1, four against BTV-8 and seven ibexes were non vaccinated controls. Seven ibexes (four vaccinated and three controls) were inoculated with each BTV serotype. Antibody and IFN-gamma responses were evaluated until 28 days after inoculation (dpi). The vaccinated ibexes showed significant (P<0.05) neutralizing antibody levels after vaccination compared to non vaccinated ibexes. The non vaccinated ibexes remained seronegative until challenge and showed neutralizing antibodies from 7 dpi. BTV RNA was detected in the blood of non vaccinated ibexes from 2 to the end of the study (28 dpi) and in target tissue samples obtained at necropsy (8 and 28 dpi). BTV-1 was successfully isolated on cell culture from blood and target tissues of non vaccinated ibexes. Clinical signs were unapparent and no gross lesions were found at necropsy. Our results show for the first time that Spanish ibex is susceptible and asymptomatic to BTV infection and also that a single dose of vaccine prevents viraemia against BTV-1 and BTV-8 replication.
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Affiliation(s)
- Cristina Lorca-Oró
- Centre de Recerca en Sanitat Animal, UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain.
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