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Drolet BS, Reister-Hendricks L, Mayo C, Rodgers C, Molik DC, McVey DS. Increased Virulence of Culicoides Midge Cell-Derived Bluetongue Virus in IFNAR Mice. Viruses 2024; 16:1474. [PMID: 39339950 DOI: 10.3390/v16091474] [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: 08/17/2024] [Revised: 09/12/2024] [Accepted: 09/13/2024] [Indexed: 09/30/2024] Open
Abstract
Bluetongue (BT) is a Culicoides midge-borne hemorrhagic disease affecting cervids and ruminant livestock species, resulting in significant economic losses from animal production and trade restrictions. Experimental animal infections using the α/β interferon receptor knockout IFNAR mouse model and susceptible target species are critical for understanding viral pathogenesis, virulence, and evaluating vaccines. However, conducting experimental vector-borne transmission studies with the vector itself are logistically difficult and experimentally problematic. Therefore, experimental infections are induced by hypodermic injection with virus typically derived from baby hamster kidney (BHK) cells. Unfortunately, for many U.S. BTV serotypes, it is difficult to replicate the severity of the disease seen in natural, midge-transmitted infections by injecting BHK-derived virus into target host animals. Using the IFNAR BTV murine model, we compared the virulence of traditional BHK cell-derived BTV-17 with C. sonorensis midge (W8) cell-derived BTV-17 to determine whether using cells of the transmission vector would provide an in vitro virulence aspect of vector-transmitted virus. At both low and high doses, mice inoculated with W8-BTV-17 had an earlier onset of viremia, earlier onset and peak of clinical signs, and significantly higher mortality compared to mice inoculated with BHK-BTV-17. Our results suggest using a Culicoides W8 cell-derived inoculum may provide an in vitro vector-enhanced infection to more closely represent disease levels seen in natural midge-transmitted infections while avoiding the logistical and experimental complexity of working with live midges.
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Affiliation(s)
- Barbara S Drolet
- Arthropod-Borne Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA
| | - Lindsey Reister-Hendricks
- Arthropod-Borne Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA
| | - Christie Mayo
- Department of Microbiology, Immunology, and Pathology, Colorado State University, 1601 Campus Delivery, Fort Collins, CO 80526, USA
| | - Case Rodgers
- Department of Microbiology, Immunology, and Pathology, Colorado State University, 1601 Campus Delivery, Fort Collins, CO 80526, USA
| | - David C Molik
- Arthropod-Borne Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA
| | - David Scott McVey
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, P.O. Box 830905, Lincoln, NE 68583, USA
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2
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Viadanna PHO, Grace SG, Logan TD, DeRuyter E, Loeb JC, Wilson KN, White ZS, Krauer JMC, Lednicky JA, Waltzek TB, Wisely SM, Subramaniam K. Characterization of two novel reassortant bluetongue virus serotype 1 strains isolated from farmed white-tailed deer (Odocoileus virginianus) in Florida, USA. Virus Genes 2023; 59:732-740. [PMID: 37439882 DOI: 10.1007/s11262-023-02019-6] [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: 05/10/2023] [Accepted: 06/27/2023] [Indexed: 07/14/2023]
Abstract
Hemorrhagic diseases caused by epizootic hemorrhagic disease virus or by bluetongue virus (BTV) are the most important orbivirus diseases affecting ruminants, including white-tailed deer (WTD). Bluetongue virus is of particular concern for farmed WTD in Florida, given its lethality and its wide distribution throughout the state. This study reports the clinical findings, ancillary diagnostics, and genomic characterization of two BTV serotype 1 strains isolated from two farmed WTD, from two different farms in Florida in 2019 and 2022. Phylogenetic and genetic analyses indicated that these two novel BTV-1 strains were reassortants. In addition, our analyses reveal that most genome segments of these strains were acquired from BTVs previously detected in ruminants in Florida, substantiating their endemism in the Southeastern U.S. Our findings underscore the need for additional research to determine the genetic diversity of BTV strains in Florida, their prevalence, and the potential risk of new BTV strains to WTD and other ruminants.
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Affiliation(s)
- Pedro H O Viadanna
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 32611, Gainesville, FL, USA
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
| | - Savannah G Grace
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Wildlife Ecology and Conservation, University of Florida, 32611, Gainesville, FL, USA
| | - Tracey D Logan
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, 32611, Gainesville, FL, USA
| | - Emily DeRuyter
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, 32611, Gainesville, FL, USA
| | - Julia C Loeb
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, 32611, Gainesville, FL, USA
| | - Kristen N Wilson
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Wildlife Ecology and Conservation, University of Florida, 32611, Gainesville, FL, USA
| | - Zoe S White
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Wildlife Ecology and Conservation, University of Florida, 32611, Gainesville, FL, USA
| | - Juan M C Krauer
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, 32611, Gainesville, FL, USA
- Washington Animal Disease Diagnostic Laboratory, Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, 99164, Pullman, WA, USA
| | - John A Lednicky
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, 32611, Gainesville, FL, USA
| | - Thomas B Waltzek
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 32611, Gainesville, FL, USA
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Washington Animal Disease Diagnostic Laboratory, Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, 99164, Pullman, WA, USA
| | - Samantha M Wisely
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA
- Department of Wildlife Ecology and Conservation, University of Florida, 32611, Gainesville, FL, USA
| | - Kuttichantran Subramaniam
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 32611, Gainesville, FL, USA.
- Emerging Pathogens Institute, University of Florida, 32611, Gainesville, FL, USA.
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3
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Van Schalkwyk A, Coetzee P, Ebersohn K, Von Teichman B, Venter E. Widespread Reassortment Contributes to Antigenic Shift in Bluetongue Viruses from South Africa. Viruses 2023; 15:1611. [PMID: 37515297 PMCID: PMC10383083 DOI: 10.3390/v15071611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/14/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Bluetongue (BT), a viral disease of ruminants, is endemic throughout South Africa, where outbreaks of different serotypes occur. The predominant serotypes can differ annually due to herd immunity provided by annual vaccinations using a live attenuated vaccine (LAV). This has led to both wild-type and vaccine strains co-circulating in the field, potentially leading to novel viral strains due to reassortment and recombination. Little is known about the molecular evolution of the virus in the field in South Africa. The purpose of this study was to investigate the genetic diversity of field strains of BTV in South Africa and to provide an initial assessment of the evolutionary processes shaping BTV genetic diversity in the field. Complete genomes of 35 field viruses belonging to 11 serotypes, collected from different regions of the country between 2011 and 2017, were sequenced. The sequences were phylogenetically analysed in relation to all the BTV sequences available from GenBank, including the LAVs and reference strains, resulting in the analyses and reassortment detection of 305 BTVs. Phylogenomic analysis indicated a geographical selection of the genome segments, irrespective of the serotype. Based on the initial assessment of the current genomic clades that circulate in South Africa, the selection for specific clades is prevalent in directing genome segment reassortment, which seems to exclude the vaccine strains and in multiple cases involves Segment-2 resulting in antigenic shift.
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Affiliation(s)
- Antoinette Van Schalkwyk
- Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa
| | - Peter Coetzee
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
| | - Karen Ebersohn
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
| | | | - Estelle Venter
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
- School of Public Health, Medical and Veterinary Sciences, Discipline Veterinary Science, James Cook University, Townsville 4811, Australia
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Kopanke J, Carpenter M, Lee J, Reed K, Rodgers C, Burton M, Lovett K, Westrich JA, McNulty E, McDermott E, Barbera C, Cavany S, Rohr JR, Perkins TA, Mathiason CK, Stenglein M, Mayo C. Bluetongue Research at a Crossroads: Modern Genomics Tools Can Pave the Way to New Insights. Annu Rev Anim Biosci 2022; 10:303-324. [PMID: 35167317 DOI: 10.1146/annurev-animal-051721-023724] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bluetongue virus (BTV) is an arthropod-borne, segmented double-stranded RNA virus that can cause severe disease in both wild and domestic ruminants. BTV evolves via several key mechanisms, including the accumulation of mutations over time and the reassortment of genome segments.Additionally, BTV must maintain fitness in two disparate hosts, the insect vector and the ruminant. The specific features of viral adaptation in each host that permit host-switching are poorly characterized. Limited field studies and experimental work have alluded to the presence of these phenomena at work, but our understanding of the factors that drive or constrain BTV's genetic diversification remains incomplete. Current research leveraging novel approaches and whole genome sequencing applications promises to improve our understanding of BTV's evolution, ultimately contributing to the development of better predictive models and management strategies to reduce future impacts of bluetongue epizootics.
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Affiliation(s)
- Jennifer Kopanke
- Office of the Campus Veterinarian, Washington State University, Spokane, Washington, USA;
| | - Molly Carpenter
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Justin Lee
- Genomic Sequencing Laboratory, Centers for Disease Control and Prevention, Atlanta, Georgia, USA;
| | - Kirsten Reed
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Case Rodgers
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Mollie Burton
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Kierra Lovett
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Joseph A Westrich
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Erin McNulty
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Emily McDermott
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, Arkansas, USA;
| | - Carly Barbera
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA; , , ,
| | - Sean Cavany
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA; , , ,
| | - Jason R Rohr
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA; , , ,
| | - T Alex Perkins
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA; , , ,
| | - Candace K Mathiason
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Mark Stenglein
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
| | - Christie Mayo
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA; , , , , , , , , ,
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Saminathan M, Singh KP, Khorajiya JH, Dinesh M, Vineetha S, Maity M, Rahman AF, Misri J, Malik YS, Gupta VK, Singh RK, Dhama K. An updated review on bluetongue virus: epidemiology, pathobiology, and advances in diagnosis and control with special reference to India. Vet Q 2021; 40:258-321. [PMID: 33003985 PMCID: PMC7655031 DOI: 10.1080/01652176.2020.1831708] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Bluetongue (BT) is an economically important, non-contagious viral disease of domestic and wild ruminants. BT is caused by BT virus (BTV) and it belongs to the genus Orbivirus and family Reoviridae. BTV is transmitted by Culicoides midges and causes clinical disease in sheep, white-tailed deer, pronghorn antelope, bighorn sheep, and subclinical manifestation in cattle, goats and camelids. BT is a World Organization for Animal Health (OIE) listed multispecies disease and causes great socio-economic losses. To date, 28 serotypes of BTV have been reported worldwide and 23 serotypes have been reported from India. Transplacental transmission (TPT) and fetal abnormalities in ruminants had been reported with cell culture adopted live-attenuated vaccine strains of BTV. However, emergence of BTV-8 in Europe during 2006, confirmed TPT of wild-type/field strains of BTV. Diagnosis of BT is more important for control of disease and to ensure BTV-free trade of animals and their products. Reverse transcription polymerase chain reaction, agar gel immunodiffusion assay and competitive enzyme-linked immunosorbent assay are found to be sensitive and OIE recommended tests for diagnosis of BTV for international trade. Control measures include mass vaccination (most effective method), serological and entomological surveillance, forming restriction zones and sentinel programs. Major hindrances with control of BT in India are the presence of multiple BTV serotypes, high density of ruminant and vector populations. A pentavalent inactivated, adjuvanted vaccine is administered currently in India to control BT. Recombinant vaccines with DIVA strategies are urgently needed to combat this disease. This review is the first to summarise the seroprevalence of BTV in India for 40 years, economic impact and pathobiology.
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Affiliation(s)
- Mani Saminathan
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Karam Pal Singh
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | | | - Murali Dinesh
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Sobharani Vineetha
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Madhulina Maity
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - At Faslu Rahman
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Jyoti Misri
- Animal Science Division, Indian Council of Agricultural Research, New Delhi, India
| | - Yashpal Singh Malik
- Division of Biological Standardization, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Vivek Kumar Gupta
- Centre for Animal Disease Research and Diagnosis, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Raj Kumar Singh
- Director, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Kuldeep Dhama
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
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6
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Ries C, Vögtlin A, Hüssy D, Jandt T, Gobet H, Hilbe M, Burgener C, Schweizer L, Häfliger-Speiser S, Beer M, Hoffmann B. Putative Novel Atypical BTV Serotype '36' Identified in Small Ruminants in Switzerland. Viruses 2021; 13:v13050721. [PMID: 33919269 PMCID: PMC8143309 DOI: 10.3390/v13050721] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 11/16/2022] Open
Abstract
We identified a putative novel atypical BTV serotype '36' in Swiss goat flocks. In the initial flock clinical signs consisting of multifocal purulent dermatitis, facial oedema and fever were observed. Following BTV detection by RT-qPCR, serotyping identified BTV-25 and also a putative novel BTV serotype in several of the affected goats. We successfully propagated the so-called "BTV-36-CH2019" strain in cell culture, developed a specific RT-qPCR targeting Segment 2, and generated the full genome by high-throughput sequencing. Furthermore, we experimentally infected goats with BTV-36-CH2019. Regularly, EDTA blood, serum and diverse swab samples were collected. Throughout the experiment, neither fever nor clinical disease was observed in any of the inoculated goats. Four goats developed BTV viremia, whereas one inoculated goat and the two contact animals remained negative. No viral RNA was detected in the swab samples collected from nose, mouth, eye, and rectum, and thus the experimental infection of goats using this novel BTV serotype delivered no indications for any clinical symptoms or vector-free virus transmission pathways. The subclinical infection of the four goats is in accordance with the reports for other atypical BTVs. However, the clinical signs of the initial goat flock did most likely not result from infection with the novel BTV-36-CH0219.
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Affiliation(s)
- Christina Ries
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (C.R.); (M.B.)
| | - Andrea Vögtlin
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland and Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (A.V.); (D.H.); (T.J.); (H.G.)
| | - Daniela Hüssy
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland and Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (A.V.); (D.H.); (T.J.); (H.G.)
| | - Tabea Jandt
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland and Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (A.V.); (D.H.); (T.J.); (H.G.)
| | - Hansjörg Gobet
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland and Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (A.V.); (D.H.); (T.J.); (H.G.)
| | - Monika Hilbe
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zürich, 8057 Zürich, Switzerland; (M.H.); (C.B.)
| | - Carole Burgener
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zürich, 8057 Zürich, Switzerland; (M.H.); (C.B.)
| | | | | | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (C.R.); (M.B.)
| | - Bernd Hoffmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (C.R.); (M.B.)
- Correspondence:
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7
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Francisco RDS, Benites LF, Lamarca AP, de Almeida LGP, Hansen AW, Gularte JS, Demoliner M, Gerber AL, de C Guimarães AP, Antunes AKE, Heldt FH, Mallmann L, Hermann B, Ziulkoski AL, Goes V, Schallenberger K, Fillipi M, Pereira F, Weber MN, de Almeida PR, Fleck JD, Vasconcelos ATR, Spilki FR. Pervasive transmission of E484K and emergence of VUI-NP13L with evidence of SARS-CoV-2 co-infection events by two different lineages in Rio Grande do Sul, Brazil. Virus Res 2021; 296:198345. [PMID: 33631222 PMCID: PMC7898980 DOI: 10.1016/j.virusres.2021.198345] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/12/2021] [Accepted: 02/13/2021] [Indexed: 12/24/2022]
Abstract
Emergence of novel SARS-CoV-2 lineages are under the spotlight of the media, scientific community and governments. Recent reports of novel variants in the United Kingdom, South Africa and Brazil (B.1.1.28-E484K) have raised intense interest because of a possible higher transmission rate or resistance to the novel vaccines. Nevertheless, the spread of B.1.1.28 (E484K) and other variants in Brazil is still unknown. In this work, we investigated the population structure and genomic complexity of SARS-CoV-2 in Rio Grande do Sul, the southernmost state in Brazil. Most samples sequenced belonged to the B.1.1.28 (E484K) lineage, demonstrating its widespread dispersion. We were the first to identify two independent events of co-infection caused by the occurrence of B.1.1.28 (E484K) with either B.1.1.248 or B.1.91 lineages. Also, clustering analysis revealed the occurrence of a novel cluster of samples circulating in the state (named VUI-NP13L) characterized by 12 lineage-defining mutations. In light of the evidence for E484K dispersion, co-infection and emergence of VUI-NP13 L in Rio Grande do Sul, we reaffirm the importance of establishing strict and effective social distancing measures to counter the spread of potentially more hazardous SARS-CoV-2 strains.
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Affiliation(s)
| | - L Felipe Benites
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Alessandra P Lamarca
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica, Petrópolis, Brazil
| | - Luiz G P de Almeida
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica, Petrópolis, Brazil
| | - Alana Witt Hansen
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | | | - Meriane Demoliner
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Alexandra L Gerber
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica, Petrópolis, Brazil
| | - Ana Paula de C Guimarães
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica, Petrópolis, Brazil
| | | | - Fagner Henrique Heldt
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Larissa Mallmann
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Bruna Hermann
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Ana Luiza Ziulkoski
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Vyctoria Goes
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | | | - Micheli Fillipi
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Francini Pereira
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Matheus Nunes Weber
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | | | - Juliane Deise Fleck
- Laboratório de Microbiologia Molecular,Universidade Feevale, Rio Grande do Sul, Brazil
| | - Ana Tereza R Vasconcelos
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica, Petrópolis, Brazil.
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8
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Kopanke J, Lee J, Stenglein M, Mayo C. In Vitro Reassortment between Endemic Bluetongue Viruses Features Global Shifts in Segment Frequencies and Preferred Segment Combinations. Microorganisms 2021; 9:microorganisms9020405. [PMID: 33669284 PMCID: PMC7920030 DOI: 10.3390/microorganisms9020405] [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: 01/25/2021] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 02/06/2023] Open
Abstract
Bluetongue virus (BTV) is an arthropod-borne pathogen that is associated with sometimes severe disease in both domestic and wild ruminants. Predominantly transmitted by Culicoides spp. biting midges, BTV is composed of a segmented, double-stranded RNA genome. Vector expansion and viral genetic changes, such as reassortment between BTV strains, have been implicated as potential drivers of ongoing BTV expansion into previously BTV-free regions. We used an in vitro system to investigate the extent and flexibility of reassortment that can occur between two BTV strains that are considered enzootic to the USA, BTV-2 and BTV-10. Whole genome sequencing (WGS) was coupled with plaque isolation and a novel, amplicon-based sequencing approach to quantitate the viral genetic diversity generated across multiple generations of in vitro propagation. We found that BTV-2 and BTV-10 were able to reassort across multiple segments, but that a preferred BTV-2 viral backbone emerged in later passages and that certain segments were more likely to be found in reassortant progeny. Our findings indicate that there may be preferred segment combinations that emerge during BTV reassortment. Moreover, our work demonstrates the usefulness of WGS and amplicon-based sequencing approaches to improve understanding of the dynamics of reassortment among segmented viruses such as BTV.
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9
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Global emergence and evolutionary dynamics of bluetongue virus. Sci Rep 2020; 10:21677. [PMID: 33303862 PMCID: PMC7729867 DOI: 10.1038/s41598-020-78673-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Accepted: 11/24/2020] [Indexed: 12/16/2022] Open
Abstract
Bluetongue virus (BTV) epidemics are responsible for worldwide economic losses of up to US$ 3 billion. Understanding the global evolutionary epidemiology of BTV is critical in designing intervention programs. Here we employed phylodynamic models to quantify the evolutionary characteristics, spatiotemporal origins, and multi-host transmission dynamics of BTV across the globe. We inferred that goats are the ancestral hosts for BTV but are less likely to be important for cross-species transmission, sheep and cattle continue to be important for the transmission and maintenance of infection between other species. Our models pointed to China and India, countries with the highest population of goats, as the likely ancestral country for BTV emergence and dispersal worldwide over 1000 years ago. However, the increased diversification and dispersal of BTV coincided with the initiation of transcontinental livestock trade after the 1850s. Our analysis uncovered important epidemiological aspects of BTV that may guide future molecular surveillance of BTV.
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10
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The Genetic Diversification of a Single Bluetongue Virus Strain Using an In Vitro Model of Alternating-Host Transmission. Viruses 2020; 12:v12091038. [PMID: 32961886 PMCID: PMC7551957 DOI: 10.3390/v12091038] [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: 07/25/2020] [Revised: 08/31/2020] [Accepted: 09/15/2020] [Indexed: 12/16/2022] Open
Abstract
Bluetongue virus (BTV) is an arbovirus that has been associated with dramatic epizootics in both wild and domestic ruminants in recent decades. As a segmented, double-stranded RNA virus, BTV can evolve via several mechanisms due to its genomic structure. However, the effect of BTV’s alternating-host transmission cycle on the virus’s genetic diversification remains poorly understood. Whole genome sequencing approaches offer a platform for investigating the effect of host-alternation across all ten segments of BTV’s genome. To understand the role of alternating hosts in BTV’s genetic diversification, a field isolate was passaged under three different conditions: (i) serial passages in Culicoides sonorensis cells, (ii) serial passages in bovine pulmonary artery endothelial cells, or (iii) alternating passages between insect and bovine cells. Aliquots of virus were sequenced, and single nucleotide variants were identified. Measures of viral population genetics were used to quantify the genetic diversification that occurred. Two consensus variants in segments 5 and 10 occurred in virus from all three conditions. While variants arose across all passages, measures of genetic diversity remained largely similar across cell culture conditions. Despite passage in a relaxed in vitro system, we found that this BTV isolate exhibited genetic stability across passages and conditions. Our findings underscore the valuable role that whole genome sequencing may play in improving understanding of viral evolution and highlight the genetic stability of BTV.
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11
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Mayo C, McDermott E, Kopanke J, Stenglein M, Lee J, Mathiason C, Carpenter M, Reed K, Perkins TA. Ecological Dynamics Impacting Bluetongue Virus Transmission in North America. Front Vet Sci 2020; 7:186. [PMID: 32426376 PMCID: PMC7212442 DOI: 10.3389/fvets.2020.00186] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/20/2020] [Indexed: 12/12/2022] Open
Abstract
Bluetongue virus (BTV) is an arbovirus transmitted to domestic and wild ruminants by certain species of Culicoides midges. The disease resulting from infection with BTV is economically important and can influence international trade and movement of livestock, the economics of livestock production, and animal welfare. Recent changes in the epidemiology of Culicoides-transmitted viruses, notably the emergence of exotic BTV genotypes in Europe, have demonstrated the devastating economic consequences of BTV epizootics and the complex nature of transmission across host-vector landscapes. Incursions of novel BTV serotypes into historically enzootic countries or regions, including the southeastern United States (US), Israel, Australia, and South America, have also occurred, suggesting diverse pathways for the transmission of these viruses. The abundance of BTV strains and multiple reassortant viruses circulating in Europe and the US in recent years demonstrates considerable genetic diversity of BTV strains and implies a history of reassortment events within the respective regions. While a great deal of emphasis is rightly placed on understanding the epidemiology and emergence of BTV beyond its natural ecosystem, the ecological contexts in which BTV maintains an enzootic cycle may also be of great significance. This review focuses on describing our current knowledge of ecological factors driving BTV transmission in North America. Information presented in this review can help inform future studies that may elucidate factors that are relevant to longstanding and emerging challenges associated with prevention of this disease.
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Affiliation(s)
- Christie Mayo
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Emily McDermott
- Entomology Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Jennifer Kopanke
- Office of the Campus Veterinarian, Washington State University, Spokane, WA, United States
| | - Mark Stenglein
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Justin Lee
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Candace Mathiason
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Molly Carpenter
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Kirsten Reed
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - T. Alex Perkins
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States
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12
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Virological, immunological and pathological findings of transplacentally transmitted bluetongue virus serotype 1 in IFNAR1-blocked mice during early and mid gestation. Sci Rep 2020; 10:2164. [PMID: 32034180 PMCID: PMC7005837 DOI: 10.1038/s41598-020-58268-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 11/05/2019] [Indexed: 01/08/2023] Open
Abstract
Transplacental transmission (TPT) of wild-type Indian BTV-1 had never been experimentally proved. This study was first time investigated TPT of Indian BTV-1 (isolated from aborted and stillborn goat fetal spleens). The sequential pathology, virological and immune cell kinetics (CD4+, CD8+ T-lymphocytes and NK cells in spleen and PBMCs), and apoptosis in IFNAR1-blocked pregnant mice during early (infected on 1 GD) and mid (infected on 8 GD) gestation have been studied. There was higher rate of TPT during mid stage (71.43%) than early (57.14%) stage. In early stage reduced implantation sites, early embryonic deaths, abortions, and necro-haemorrhagic lesions had observed. Mid stage, congenital defects and neurological lesions in foetuses like haemorrhages, diffuse cerebral edema, necrotizing encephalitis and decreased bone size (Alizarin red staining) were noticed. BTV-1 antigen was first time demonstrable in cells of mesometrium, decidua of embryos, placenta, uterus, ovary, and brain of foetuses by immunohistochemistry and quantified by real-time qRT-PCR. BTV-inoculated mice were seroconverted by 7 and 5 dpi, and reached peak levels by 15 and 9 dpi in early and mid gestation, respectively. CD4+ and CD8+ cells were significantly decreased (increased ratio) on 7 dpi but subsequently increased on 15 dpi in early gestation. In mid gestation, increased CD8+ cells (decreased ratio) were observed. Apoptotic cells in PBMCs and tissues increased during peak viral load. This first time TPT of wild-type Indian BTV-1 deserves to be reported for implementation of control strategies. This model will be very suitable for further research into mechanisms of TPT, overwintering, and vaccination strategies.
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Reliable and Standardized Animal Models to Study the Pathogenesis of Bluetongue and Schmallenberg Viruses in Ruminant Natural Host Species with Special Emphasis on Placental Crossing. Viruses 2019; 11:v11080753. [PMID: 31443153 PMCID: PMC6722754 DOI: 10.3390/v11080753] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/19/2019] [Accepted: 08/13/2019] [Indexed: 01/03/2023] Open
Abstract
Starting in 2006, bluetongue virus serotype 8 (BTV8) was responsible for a major epizootic in Western and Northern Europe. The magnitude and spread of the disease were surprisingly high and the control of BTV improved significantly with the marketing of BTV8 inactivated vaccines in 2008. During late summer of 2011, a first cluster of reduced milk yield, fever, and diarrhoea was reported in the Netherlands. Congenital malformations appeared in March 2012 and Schmallenberg virus (SBV) was identified, becoming one of the very few orthobunyaviruses distributed in Europe. At the start of both epizootics, little was known about the pathogenesis and epidemiology of these viruses in the European context and most assumptions were extrapolated based on other related viruses and/or other regions of the World. Standardized and repeatable models potentially mimicking clinical signs observed in the field are required to study the pathogenesis of these infections, and to clarify their ability to cross the placental barrier. This review presents some of the latest experimental designs for infectious disease challenges with BTV or SBV. Infectious doses, routes of infection, inoculum preparation, and origin are discussed. Particular emphasis is given to the placental crossing associated with these two viruses.
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14
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Endless Forms: Within-Host Variation in the Structure of the West Nile Virus RNA Genome during Serial Passage in Bird Hosts. mSphere 2019; 4:4/3/e00291-19. [PMID: 31243074 PMCID: PMC6595145 DOI: 10.1128/msphere.00291-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The enzymes that copy RNA genomes lack proofreading, and viruses that possess RNA genomes, such as West Nile virus, rapidly diversify into swarms of mutant lineages within a host. Intrahost variation of the primary genomic sequence of RNA viruses has been studied extensively because the extent of this variation shapes key virus phenotypes. However, RNA genomes also form complex secondary structures based on within-genome nucleotide complementarity, which are critical regulators of the cyclization of the virus genome that is necessary for efficient replication and translation. We sought to characterize variation in these secondary structures within populations of West Nile virus during serial passage in three bird species. Our study indicates that the intrahost population of West Nile virus is a diverse assortment of RNA secondary structures that should be considered in future analyses of intrahost viral diversity, but some regions that are critical for genome cyclization are conserved within hosts. Besides potential impacts on viral replication, structural diversity can influence the efficacy of small RNA antiviral therapies. RNA viruses are infamous for their high rates of mutation, which produce swarms of genetic variants within individual hosts. To date, analyses of intrahost genetic diversity have focused on the primary genome sequence. However, virus phenotypes are shaped not only by primary sequence but also by the secondary structures into which this sequence folds. Such structures enable viral replication, translation, and binding of small RNAs, yet within-host variation at the structural level has not been adequately explored. We characterized the structural diversity of the 5′ untranslated region (UTR) of populations of West Nile virus (WNV) that had been subject to five serial passages in triplicate in each of three bird species. Viral genomes were sampled from host serum samples at each passage (n = 45 populations) and subjected to next-generation sequencing. For populations derived from passages 1, 3, and 5 (n = 9 populations), we predicted the impact of each mutation occurring at a frequency of ≥1% on the secondary structure of the 5′ UTR. As expected, mutations in double-stranded (DS) regions of the 5′ UTR stem structures caused structural changes of significantly greater magnitude than did mutations in single-stranded (SS) regions. Despite the greater impact of mutations in DS regions, mutations in DS and SS regions occurred at similar frequencies, with no evidence of enhanced selection against mutation in DS regions. In contrast, mutations in two regions that mediate genome cyclization and thereby regulate replication and translation, the 5′ cyclization sequence and the UAR flanking stem (UFS), were suppressed in all three hosts. IMPORTANCE The enzymes that copy RNA genomes lack proofreading, and viruses that possess RNA genomes, such as West Nile virus, rapidly diversify into swarms of mutant lineages within a host. Intrahost variation of the primary genomic sequence of RNA viruses has been studied extensively because the extent of this variation shapes key virus phenotypes. However, RNA genomes also form complex secondary structures based on within-genome nucleotide complementarity, which are critical regulators of the cyclization of the virus genome that is necessary for efficient replication and translation. We sought to characterize variation in these secondary structures within populations of West Nile virus during serial passage in three bird species. Our study indicates that the intrahost population of West Nile virus is a diverse assortment of RNA secondary structures that should be considered in future analyses of intrahost viral diversity, but some regions that are critical for genome cyclization are conserved within hosts. Besides potential impacts on viral replication, structural diversity can influence the efficacy of small RNA antiviral therapies.
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15
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Saxena A, Biswas SK, Chand K, Chauhan A, Mohd G, Subramaniam S, Naskar J, Mondal B, Ramakrishnan MA, Pandey AB. Genetic characterization and ex-vivo neutralization behavior of bluetongue virus serotype-16 recovered from apparently healthy goat. Acta Trop 2019; 194:13-22. [PMID: 30876937 DOI: 10.1016/j.actatropica.2019.03.018] [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: 12/28/2018] [Revised: 02/25/2019] [Accepted: 03/11/2019] [Indexed: 11/29/2022]
Abstract
Bluetongue virus (BTV) infects almost all the domestic and wild ruminants though the clinical disease is most commonly reported in sheep and some species of deer. Goat and cattle are the most common asymptomatic reservoir of the virus. Full genome sequencing and serological characterization of the virus isolates are emphasized for understanding the phylogenetic relationship and molecular epidemiology of bluetongue (BT). In this study, we report phylogenetic and phenotypic antigenic relationship of a BTV serotype-16 (PDP2/13/Ind) recovered from an apparently healthy goat from the state of Uttarakhand, a hilly terrain of sub-Himalayan India with four other BTV-16 isolates. The full genome sequence data was analyzed and the phylogenetic relationship of the goat isolate with other BTV-16 was established. Phylogenetic analysis revealed cluster of PDP2/13/Ind along with other Indian BTV-16 isolates indicating their close ancestral relationship. A cohesive ancestral relationship, irrespective of the genome segments analyzed, was also observed between Indian and Mediterranean BTV-16. The mean substitution rate of different segments of BTV-16 isolates varied from 3.231 × 10-5 (seg-2) to 1.129 × 10-3 (seg-6) substitutions per site per year. Timescale analysis indicated that all the segments had an older ancestor. No statistically significant geographic structuring of BTV-16 isolates was observed indicating frequent gene flow. The goat isolate shares highest identity (99.5%-99.8%) with G53/ABT/HSR, a BTV-16 recovered from the western part of the country whereas high level of divergence (11.9%-33.3%) at genomic segment level was observed with a Nigerian BTV-16 (NIG1982/10). Phenotypic antigenic relationship (r) of PDP2/13/Ind with other isolate-specific hyperimmune serum (HIS) determined from serum neutralization titer was 0.672 ± 0.058 to 0.948 ± 0.09. On other hand, the calculated 'r' score was 0.636 ± 0.063 to 0.814 ± 0.201 when HIS against PDP2/13/Ind was used to neutralize the other BTV-16 isolates. The percentage antigenic similarity (R) of the PDP2/13/Ind with other BTV-16 isolates was 65.39 ± 5.38-87.67 ± 14.86. Data suggests presence of subtype antigenic variation amongst the BTV-16 isolates recovered from the goats of a geographically restricted area of the state of Uttarakhand, India.
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Affiliation(s)
- Arpit Saxena
- Division of Virology, Indian Veterinary Research Institute Mukteswar, Nainital, Uttarakhand, 263 138, India; Department of Molecular and Cellular Engineering, Sam Higginbottom University of Agriculture Technology and Sciences Allahabad, Uttar Pradesh, 211 007, India
| | - Sanchay Kumar Biswas
- Division of Virology, Indian Veterinary Research Institute Mukteswar, Nainital, Uttarakhand, 263 138, India.
| | - Karam Chand
- Division of Virology, Indian Veterinary Research Institute Mukteswar, Nainital, Uttarakhand, 263 138, India
| | - Ankita Chauhan
- Division of Virology, Indian Veterinary Research Institute Mukteswar, Nainital, Uttarakhand, 263 138, India
| | - Gulam Mohd
- Division of Biological standardization, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, 243122, India
| | - Saravanan Subramaniam
- ICAR-Directorate of Foot and Mouth Disease, Mukteswar, Nainital, Uttarakhand, 263 138, India
| | - Jishnu Naskar
- Department of Molecular and Cellular Engineering, Sam Higginbottom University of Agriculture Technology and Sciences Allahabad, Uttar Pradesh, 211 007, India
| | - Bimalendu Mondal
- Eastern Regional Station, Indian Veterinary Research Institute, Kolkata, West Bengal, 700 037, India
| | - Muthannan A Ramakrishnan
- Division of Virology, Indian Veterinary Research Institute Mukteswar, Nainital, Uttarakhand, 263 138, India
| | - Awadh Bihari Pandey
- Division of Biological standardization, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, 243122, India
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16
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Pfaff F, Müller T, Freuling CM, Fehlner-Gardiner C, Nadin-Davis S, Robardet E, Cliquet F, Vuta V, Hostnik P, Mettenleiter TC, Beer M, Höper D. In-depth genome analyses of viruses from vaccine-derived rabies cases and corresponding live-attenuated oral rabies vaccines. Vaccine 2018; 37:4758-4765. [PMID: 29439868 DOI: 10.1016/j.vaccine.2018.01.083] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 01/19/2018] [Accepted: 01/28/2018] [Indexed: 01/23/2023]
Abstract
Live-attenuated rabies virus strains such as those derived from the field isolate Street Alabama Dufferin (SAD) have been used extensively and very effectively as oral rabies vaccines for the control of fox rabies in both Europe and Canada. Although these vaccines are safe, some cases of vaccine-derived rabies have been detected during rabies surveillance accompanying these campaigns. In recent analysis it was shown that some commercial SAD vaccines consist of diverse viral populations, rather than clonal genotypes. For cases of vaccine-derived rabies, only consensus sequence data have been available to date and information concerning their population diversity was thus lacking. In our study, we used high-throughput sequencing to analyze 11 cases of vaccine-derived rabies, and compared their viral population diversity to the related oral rabies vaccines using pairwise Manhattan distances. This extensive deep sequencing analysis of vaccine-derived rabies cases observed during oral vaccination programs provided deeper insights into the effect of accidental in vivo replication of genetically diverse vaccine strains in the central nervous system of target and non-target species under field conditions. The viral population in vaccine-derived cases appeared to be clonal in contrast to their parental vaccines. The change from a state of high population diversity present in the vaccine batches to a clonal genotype in the affected animal may indicate the presence of a strong bottleneck during infection. In conclusion, it is very likely that these few cases are the consequence of host factors and not the result of the selection of a more virulent genotype. Furthermore, this type of vaccine-derived rabies leads to the selection of clonal genotypes and the selected variants were genetically very similar to potent SAD vaccines that have undergone a history of in vitro selection.
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Affiliation(s)
- Florian Pfaff
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany.
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany.
| | - Conrad M Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany.
| | - Christine Fehlner-Gardiner
- Centre of Expertise for Rabies, Ottawa Laboratory-Fallowfield, Canadian Food Inspection Agency, Ottawa, Canada.
| | - Susan Nadin-Davis
- Centre of Expertise for Rabies, Ottawa Laboratory-Fallowfield, Canadian Food Inspection Agency, Ottawa, Canada.
| | - Emmanuelle Robardet
- Nancy Laboratory for Rabies and Wildlife, French Agency for Food, Environmental and Occupational Health & Safety, Malzéville, France.
| | - Florence Cliquet
- Nancy Laboratory for Rabies and Wildlife, French Agency for Food, Environmental and Occupational Health & Safety, Malzéville, France.
| | - Vlad Vuta
- Institute for Diagnosis and Animal Health, University of Agronomic Study and Veterinary Medicine, Faculty of Veterinary Medicine, Bucharest, Romania.
| | - Peter Hostnik
- Virology Unit, Veterinary Faculty, Institute of Microbiology and Parasitology, University of Ljubljana, Ljubljana, Slovenia.
| | - Thomas C Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany.
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany.
| | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Germany.
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17
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Gaudreault NN, Mayo CE, Jasperson DC, Crossley BM, Breitmeyer RE, Johnson DJ, Ostlund EN, MacLachlan NJ, Wilson WC. Whole genome sequencing and phylogenetic analysis of Bluetongue virus serotype 2 strains isolated in the Americas including a novel strain from the western United States. J Vet Diagn Invest 2018; 26:553-557. [PMID: 24916442 DOI: 10.1177/1040638714536902] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Bluetongue is a potentially fatal arboviral disease of domestic and wild ruminants that is characterized by widespread edema and tissue necrosis. Bluetongue virus (BTV) serotypes 10, 11, 13, and 17 occur throughout much of the United States, whereas serotype 2 (BTV-2) was previously only detected in the southeastern United States. Since 1998, 10 other BTV serotypes have also been isolated from ruminants in the southeastern United States. In 2010, BTV-2 was identified in California for the first time, and preliminary sequence analysis indicated that the virus isolate was closely related to BTV strains circulating in the southeastern United States. In the current study, the whole genome sequence of the California strain of BTV-2 was compared with those of other BTV-2 strains in the Americas. The results of the analysis suggest co-circulation of genetically distinct viruses in the southeastern United States, and further suggest that the 2010 western isolate is closely related to southeastern strains of BTV. Although it remains uncertain as to how this novel virus was translocated to California, the findings of the current study underscore the need for ongoing surveillance of this economically important livestock disease.
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Affiliation(s)
- Natasha N Gaudreault
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - Christie E Mayo
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - Dane C Jasperson
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - Beate M Crossley
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - Richard E Breitmeyer
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - Donna J Johnson
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - Eileen N Ostlund
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - N James MacLachlan
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
| | - William C Wilson
- Arthropod-Borne Animal Diseases Research Unit, U.S. Department of Agriculture (USDA), Agricultural Research Service, Manhattan, KS (Gaudreault, Jasperson, Wilson).,Department of Pathology, Microbiology and Immunology (Mayo, MacLachlan), School of Veterinary Medicine, University of California, Davis, CA.,California Animal Health and Food Safety Laboratory (Crossley, Breitmeyer), School of Veterinary Medicine, University of California, Davis, CA.,Diagnostic Virology Laboratory, National Veterinary Services Laboratories, USDA, Animal and Plant Health Inspection Service, Ames, IA (Johnson, Ostlund)
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18
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Maclachlan NJ, Osburn BI. Teratogenic bluetongue and related orbivirus infections in pregnant ruminant livestock: timing and pathogen genetics are critical. Curr Opin Virol 2017; 27:31-35. [PMID: 29107849 DOI: 10.1016/j.coviro.2017.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/26/2017] [Accepted: 10/11/2017] [Indexed: 10/18/2022]
Abstract
Congenital infections of domestic animals with viruses in several families, including Bunyaviridae, Flaviridae, Parvoviridae, and Reoviridae, are the cause of naturally occurring teratogenic central nervous system and/or musculoskeletal defects (arthrogryposis) in domestic animals. Congenital infections of ruminant livestock with bluetongue virus (BTV) and some related members of the genus Orbivirus (family Reoviridae) have clearly shown the critical role of gestational age at infection in determining outcome. Specifically, fetuses infected prior to mid-gestation that survive congenital BTV infection are born with cavitating central nervous system defects that range from severe hydranencephaly to cerebral cysts (porencephaly). Generally, the younger the fetus (in terms of gestational age) at infection, the more severe the teratogenic lesion at birth. Age-dependent virus infection and destruction of neuronal and/or glial cell precursors that populate the developing central nervous system are responsible for these naturally occurring virus-induced congenital defects of animals, thus lesions are most severe when progenitor cells are infected prior to their normal migration during embryogenesis. Whereas congenital infection is characteristic of certain BTV strains, notably live-attenuated (modified-live) vaccine viruses that have been passaged in embryonating eggs, transplacental transmission is not characteristic of many field strains of the virus and much remains to be determined regarding the genetic determinants of transplacental transmission of individual virus strains.
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Affiliation(s)
- N James Maclachlan
- School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
| | - Bennie I Osburn
- School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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19
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Abstract
Bluetongue virus (BTV) is the type species of genus Orbivirus within family Reoviridae. Bluetongue virus is transmitted between its ruminant hosts by the bite of Culicoides spp. midges. Severe BT cases are characterized by symptoms including hemorrhagic fever, particularly in sheep, loss of productivity, and death. To date, 27 BTV serotypes have been documented. These include novel isolates of atypical BTV, which have been almost fully characterized using deep sequencing technologies and do not rely on Culicoides vectors for their transmission among hosts. Due to its high economic impact, BT is an Office International des Epizooties (OIE) listed disease that is strictly controlled in international commercial exchanges. During the 20th century, BTV has been endemic in subtropical regions. In the last 15 years, novel strains of nine "typical" BTV serotypes (1, 2, 4, 6, 8, 9, 11, 14, and 16) invaded Europe, some of which caused disease in naive sheep and unexpectedly in bovine herds (particularly serotype 8). Over the past few years, three novel "atypical" serotypes (25-27) were characterized during sequencing studies of animal samples from Switzerland, Kuwait, and France, respectively. Classical serotype-specific inactivated vaccines, although expensive, were very successful in controlling outbreaks as shown with the northern European BTV-8 outbreak which started in the summer of 2006. Technological jumps in deep sequencing methodologies made rapid full characterizations of BTV genome from isolates/tissues feasible. Next-generation sequencing (NGS) approaches are powerful tools to study the variability of BTV genomes on a fine scale. This paper provides information on how NGS impacted our knowledge of the BTV genome.
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A Deterministic Model to Quantify Risk and Guide Mitigation Strategies to Reduce Bluetongue Virus Transmission in California Dairy Cattle. PLoS One 2016; 11:e0165806. [PMID: 27812161 PMCID: PMC5094782 DOI: 10.1371/journal.pone.0165806] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 10/18/2016] [Indexed: 11/19/2022] Open
Abstract
The global distribution of bluetongue virus (BTV) has been changing recently, perhaps as a result of climate change. To evaluate the risk of BTV infection and transmission in a BTV-endemic region of California, sentinel dairy cows were evaluated for BTV infection, and populations of Culicoides vectors were collected at different sites using carbon dioxide. A deterministic model was developed to quantify risk and guide future mitigation strategies to reduce BTV infection in California dairy cattle. The greatest risk of BTV transmission was predicted within the warm Central Valley of California that contains the highest density of dairy cattle in the United States. Temperature and parameters associated with Culicoides vectors (transmission probabilities, carrying capacity, and survivorship) had the greatest effect on BTV's basic reproduction number, R0. Based on these analyses, optimal control strategies for reducing BTV infection risk in dairy cattle will be highly reliant upon early efforts to reduce vector abundance during the months prior to peak transmission.
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Stenger DC, Krugner R, Nouri S, Ferriol I, Falk BW, Sisterson MS. Sequence polymorphism in an insect RNA virus field population: A snapshot from a single point in space and time reveals stochastic differences among and within individual hosts. Virology 2016; 498:209-217. [PMID: 27598532 DOI: 10.1016/j.virol.2016.08.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 08/26/2016] [Accepted: 08/27/2016] [Indexed: 02/02/2023]
Abstract
Population structure of Homalodisca coagulata Virus-1 (HoCV-1) among and within field-collected insects sampled from a single point in space and time was examined. Polymorphism in complete consensus sequences among single-insect isolates was dominated by synonymous substitutions. The mutant spectrum of the C2 helicase region within each single-insect isolate was unique and dominated by nonsynonymous singletons. Bootstrapping was used to correct the within-isolate nonsynonymous:synonymous arithmetic ratio (N:S) for RT-PCR error, yielding an N:S value ~one log-unit greater than that of consensus sequences. Probability of all possible single-base substitutions for the C2 region predicted N:S values within 95% confidence limits of the corrected within-isolate N:S when the only constraint imposed was viral polymerase error bias for transitions over transversions. These results indicate that bottlenecks coupled with strong negative/purifying selection drive consensus sequences toward neutral sequence space, and that most polymorphism within single-insect isolates is composed of newly-minted mutations sampled prior to selection.
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Affiliation(s)
- Drake C Stenger
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Ave., Parlier, CA 93648-9757, USA.
| | - Rodrigo Krugner
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Ave., Parlier, CA 93648-9757, USA
| | - Shahideh Nouri
- Department of Plant Pathology, University of California, Davis, CA 95616, USA
| | - Inmaculada Ferriol
- Department of Plant Pathology, University of California, Davis, CA 95616, USA
| | - Bryce W Falk
- Department of Plant Pathology, University of California, Davis, CA 95616, USA
| | - Mark S Sisterson
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Ave., Parlier, CA 93648-9757, USA
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Marín-López A, Barriales D, Moreno S, Ortego J, Calvo-Pinilla E. Defeating Bluetongue virus: new approaches in the development of multiserotype vaccines. Future Virol 2016. [DOI: 10.2217/fvl-2016-0061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Bluetongue virus (BTV) is a global threat to domestic and wild ruminants, causing massive economic losses throughout the world. New serotypes of the virus are rapidly emerging in different continents, unfortunately there is little cross-protection between BTV serotypes. The eradication of the virus from a region is particularly complicated in areas where multiple serotypes circulate for a long time. The present review summarizes the actual concerns about the spread of the virus and relevant approaches to develop efficient vaccines against BTV, in particular those focused on a multiserotype design.
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Affiliation(s)
| | - Diego Barriales
- Centro de Investigación en Sanidad Animal, INIA-CISA, Valdeolmos-Madrid, Spain
| | - Sandra Moreno
- Centro de Investigación en Sanidad Animal, INIA-CISA, Valdeolmos-Madrid, Spain
| | - Javier Ortego
- Centro de Investigación en Sanidad Animal, INIA-CISA, Valdeolmos-Madrid, Spain
| | - Eva Calvo-Pinilla
- Centro de Investigación en Sanidad Animal, INIA-CISA, Valdeolmos-Madrid, Spain
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Jiménez-Clavero MA, Agüero M, San Miguel E, Mayoral T, López MC, Ruano MJ, Romero E, Monaco F, Polci A, Savini G, Gómez-Tejedor C. High Throughput Detection of Bluetongue Virus by a New Real-Time Fluorogenic Reverse Transcription—Polymerase Chain Reaction: Application on Clinical Samples from Current Mediterranean Outbreaks. J Vet Diagn Invest 2016; 18:7-17. [PMID: 16566253 DOI: 10.1177/104063870601800103] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A real-time reverse transcription-polymerase chain reaction (RT-PCR) assay was developed for the detection of bluetongue virus (BTV) in blood samples. A combination of primers specific for a highly conserved region in RNA segment 5 (based on Mediterranean BTV sequences) and a DNA probe bound to 5′-Taq nuclease-3′ minor groove binder (TaqMan© MGB) was used to detect a range of isolates. This real-time RT-PCR assay could detect 5.4 × 10−3 tissue culture infectious doses (TCID50) of virus per milliliter of sample, which was comparable to our current BTV diagnostic nested RT-PCR assay. The assay detected all recent Mediterranean isolates (including serotypes 2, 4, and 16), BTV vaccine strains for serotypes 2 and 4, and 15 out of the 24 BTV reference strains available (all serotypes), but did not detect the related orbiviruses epizootic hemorrhagic disease and African horse sickness viruses. Following assay evaluation, the ability of this assay to identify BTV in recent isolates (2003, 2004) from ovine and bovine samples from an epizootic outbreak in Spain was also tested. Minor nucleotide changes (detected by sequencing viral genomes) within the probe-binding region were found to have a profound effect on virus detection. This assay has the benefits of being fast and simple, and the 96-well format enables large-scale epidemiological screening for BTV, especially when combined with a high-throughput nucleic acid extraction method.
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McVey DS, Drolet BS, Ruder MG, Wilson WC, Nayduch D, Pfannenstiel R, Cohnstaedt LW, MacLachlan NJ, Gay CG. Orbiviruses: A North American Perspective. Vector Borne Zoonotic Dis 2016; 15:335-8. [PMID: 26086554 DOI: 10.1089/vbz.2014.1699] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Orbiviruses are members of the Reoviridae family and include bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). These viruses are the cause of significant regional disease outbreaks among livestock and wildlife in the United States, some of which have been characterized by significant morbidity and mortality. Competent vectors are clearly present in most regions of the globe; therefore, all segments of production livestock are at risk for serious disease outbreaks. Animals with subclinical infections also serve as reservoirs of infection and often result in significant trade restrictions. The economic and explicit impacts of BTV and EHDV infections are difficult to measure, but infections are a cause of economic loss for producers and loss of natural resources (wildlife). In response to United States Animal Health Association (USAHA) Resolution 16, the US Department of Agriculture (USDA), in collaboration with the Department of the Interior (DOI), organized a gap analysis workshop composed of international experts on Orbiviruses. The workshop participants met at the Arthropod-Borne Animal Diseases Research Unit in Manhattan, KS, May 14-16, 2013, to assess the available scientific information and status of currently available countermeasures to effectively control and mitigate the impact of an outbreak of an emerging Orbivirus with epizootic potential, with special emphasis given to BTV and EHDV. In assessing the threats, workshop participants determined that available countermeasures are somewhat effective, but several weaknesses were identified that affect their ability to prevent and control disease outbreaks effectively.
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Affiliation(s)
- D Scott McVey
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - Barbara S Drolet
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - Mark G Ruder
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - William C Wilson
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - Dana Nayduch
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - Robert Pfannenstiel
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - Lee W Cohnstaedt
- 1 US Department of Agriculture, Agricultural Research Service, Arthropod-Borne Animal Diseases Research Unit , Manhattan, Kansas
| | - N James MacLachlan
- 2 Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California , Davis, California
| | - Cyril G Gay
- 3 US Department of Agriculture, Agricultural Research Service, National Program 103-Animal Health , Beltsville, Maryland
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Steyn J, Venter EH. Sequence analysis and evaluation of the NS3/A gene region of bluetongue virus isolates from South Africa. Arch Virol 2016; 161:947-57. [PMID: 26780892 DOI: 10.1007/s00705-015-2741-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 12/21/2015] [Indexed: 11/24/2022]
Abstract
Phylogenetic networks and sequence analysis allow a more accurate understanding of the serotypes, genetic relationships and epidemiology of viruses. Based on gene sequences of the conserved segment 10 (NS3), bluetongue virus (BTV) can be divided into five topotypes. In this molecular epidemiology study, segment 10 sequence data of 11 isolates obtained from the Virology Section of the Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, were analyzed and compared to sequence data of worldwide BTV strains available in the GenBank database. The consensus nucleotide sequences of NS3/A showed intermediate levels of variation, with the nucleotide sequence identity ranging from 79.72 % to 100 %. All 11 strains demonstrated conserved amino acid characteristics. Phylogenetic networks were used to identify BTV topotypes. The phylogeny obtained from the nucleotide sequence data of the NS3/A-encoding gene presented three major and two minor topotypes. The clustering of strains from different geographical areas into the same group indicated spatial spread of the segment 10 genes, either through gene reassortment or through the introduction of new strains from other geographical areas via trade. The effect of reassortment and genetic drift on BTV and the importance of correct serotyping to identify viral strains are highlighted.
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Affiliation(s)
- Jumari Steyn
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
| | - Estelle Hildegard Venter
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
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Nomikou K, Hughes J, Wash R, Kellam P, Breard E, Zientara S, Palmarini M, Biek R, Mertens P. Widespread Reassortment Shapes the Evolution and Epidemiology of Bluetongue Virus following European Invasion. PLoS Pathog 2015; 11:e1005056. [PMID: 26252219 PMCID: PMC4529188 DOI: 10.1371/journal.ppat.1005056] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 06/30/2015] [Indexed: 11/24/2022] Open
Abstract
Genetic exchange by a process of genome-segment ‘reassortment’ represents an important mechanism for evolutionary change in all viruses with segmented genomes, yet in many cases a detailed understanding of its frequency and biological consequences is lacking. We provide a comprehensive assessment of reassortment in bluetongue virus (BTV), a globally important insect-borne pathogen of livestock, during recent outbreaks in Europe. Full-genome sequences were generated and analysed for over 150 isolates belonging to the different BTV serotypes that have emerged in the region over the last 5 decades. Based on this novel dataset we confirm that reassortment is a frequent process that plays an important and on-going role in evolution of the virus. We found evidence for reassortment in all ten segments without a significant bias towards any particular segment. However, we observed biases in the relative frequency at which particular segments were associated with each other during reassortment. This points to selective constraints possibly caused by functional relationships between individual proteins or genome segments and genome-wide epistatic interactions. Sites under positive selection were more likely to undergo amino acid changes in newly reassorted viruses, providing additional evidence for adaptive dynamics as a consequence of reassortment. We show that the live attenuated vaccines recently used in Europe have repeatedly reassorted with field strains, contributing to their genotypic, and potentially phenotypic, variability. The high degree of plasticity seen in the BTV genome in terms of segment origin suggests that current classification schemes that are based primarily on serotype, which is determined by only a single genome segment, are inadequate. Our work highlights the need for a better understanding of the mechanisms and epidemiological consequences of reassortment in BTV, as well as other segmented RNA viruses. Segmented viruses have genomes that are separated into multiple segments, comparable to chromosomes in higher organisms. When two segmented viruses of the same species infect the same cell, their progeny may incorporate segments picked up from the “parental” viruses. This process is called “reassortment” and represents an important way for segmented viruses to evolve. Whereas reassortment has received a lot of attention in certain segmented viruses, especially influenza A, its frequency and biological consequences remain poorly understood for most of the others. Here, we present a comprehensive analysis of the reassortment patterns in bluetongue virus, an important pathogen of livestock, during its repeated emergence in Europe in recent decades. We confirm earlier reports that reassortment is common and can involve segments derived from live vaccines used to control outbreaks. However, the mixing of viral genomes is not strictly random and reassortment is commonly followed by novel adaptive changes in the progeny virus. This points to important functional links (paired associations) between certain segments. Our findings have important implications for the classification and control of segmented viruses and generate new insights and hypotheses about the biological interactions among different parts of the bluetongue virus genome.
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Affiliation(s)
- Kyriaki Nomikou
- Vector-Borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Woking, United Kingdom
| | - Joseph Hughes
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Rachael Wash
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Paul Kellam
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Division of Infection and Immunity, Research Department of Infection, University College London, London, United Kingdom
| | - Emmanuel Breard
- French Agency for Food, Environment and Occupational Health and Safety (ANSES), Maisons-Alfort, France
| | - Stéphan Zientara
- French Agency for Food, Environment and Occupational Health and Safety (ANSES), Maisons-Alfort, France
| | - Massimo Palmarini
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Roman Biek
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
- Institute of Biodiversity, Animal Health and Comparative Medicine, Boyd Orr Centre for Population and Ecosystem Health, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail: (RB); (PM)
| | - Peter Mertens
- Vector-Borne Viral Diseases Programme, The Pirbright Institute, Pirbright, Woking, United Kingdom
- * E-mail: (RB); (PM)
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Zientara S, Ponsart C. Viral emergence and consequences for reproductive performance in ruminants: two recent examples (bluetongue and Schmallenberg viruses). Reprod Fertil Dev 2015; 27:63-71. [PMID: 25472045 DOI: 10.1071/rd14367] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Viruses can emerge unexpectedly in different regions of the world and may have negative effects on reproductive performance. This paper describes the consequences for reproductive performance that have been reported after the introduction to Europe of two emerging viruses, namely the bluetongue (BTV) and Schmallenberg (SBV) viruses. Following the extensive spread of BTV in northern Europe, large numbers of pregnant cows were infected with BTV serotype 8 (BTV-8) during the breeding season of 2007. Initial reports of some cases of abortion and hydranencephaly in cattle in late 2007 were followed by quite exhaustive investigations in the field that showed that 10%-35% of healthy calves were infected with BTV-8 before birth. Transplacental transmission and fetal abnormalities in cattle and sheep had been previously observed only with strains of the virus that were propagated in embryonated eggs and/or cell culture, such as vaccine strains or vaccine candidate strains. After the unexpected emergence of BTV-8 in northern Europe in 2006, another arbovirus, namely SBV, emerged in Europe in 2011, causing a new economically important disease in ruminants. This new virus, belonging to the Orthobunyavirus genus in the Bunyaviridae family, was first detected in Germany, in The Netherlands and in Belgium in 2011 and soon after in the UK, France, Italy, Luxembourg, Spain, Denmark and Switzerland. Adult animals show no or only mild clinical symptoms, whereas infection during a critical period of gestation can lead to abortion, stillbirth or the birth of severely malformed offspring. The impact of the disease is usually greater in sheep than in cattle. The consequences of SBV infection in domestic ruminants and more precisely the secondary effects on off-springs will be described.
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Affiliation(s)
- Stéphan Zientara
- UPE, ANSES, INRA, ENVA, UMR 1161 ANSES/INRA/ENVA, Laboratoire de santé animale d'Alfort, 23 Avenue du Général de gaulle, 94703 Maisons-Alfort, France
| | - Claire Ponsart
- ANSES, Unité des zoonoses bactériennes, Laboratoire de santé animale d'Alfort, 23 Avenue du Général de gaulle, 94703 Maisons-Alfort, France
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Biswas SK, Chand K, Rehman W, Reddy YN, Mondal B. Segment-2 sequencing and cross-neutralization studies confirm existence of a neutralization resistant VP2 phenotypic variant of bluetongue virus serotype 1 in India. Vet Microbiol 2015; 176:358-64. [DOI: 10.1016/j.vetmic.2015.01.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/29/2015] [Accepted: 01/30/2015] [Indexed: 01/05/2023]
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Jupille H, Vega-Rua A, Rougeon F, Failloux AB. Arboviruses: variations on an ancient theme. Future Virol 2014. [DOI: 10.2217/fvl.14.62] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
ABSTRACT Arboviruses utilize different strategies to complete their transmission cycle between vertebrate and invertebrate hosts. Most possess an RNA genome coupled with an RNA polymerase lacking proofreading activity and generate large populations of genetically distinct variants, permitting rapid adaptation to environmental changes. With mutation rates of between 10- 6 and 10-4 substitutions per nucleotide, arboviral genomes rapidly acquire mutations that can lead to viral emergence. Arboviruses can be described in seven families, four of which have medical importance: Togaviridae, Flaviviridae, Bunyaviridae and Reoviridae. The Togaviridae and Flaviviridae both have ssRNA genomes, while the Bunyaviridae and Reoviridae possess segmented RNA genomes. Recent epidemics caused by these arboviruses have been associated with specific mutations leading to enhanced host ranges, vector shifts and virulence.
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Affiliation(s)
- Henri Jupille
- Department of Virology, Arboviruses & Insect Vectors, 25 Rue du Dr Roux, 75724 Paris Cedex 15, France
| | - Anubis Vega-Rua
- Department of Virology, Arboviruses & Insect Vectors, 25 Rue du Dr Roux, 75724 Paris Cedex 15, France
- Cellule Pasteur UPMC, Université Pierre et Marie Curie, Paris, France
| | | | - Anna-Bella Failloux
- Department of Virology, Arboviruses & Insect Vectors, 25 Rue du Dr Roux, 75724 Paris Cedex 15, France
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Abstract
Bluetongue is a major infectious disease of ruminants caused by bluetongue virus (BTV), an arbovirus transmitted by Culicoides. Here, we assessed virus and host factors influencing the clinical outcome of BTV infection using a single experimental framework. We investigated how mammalian host species, breed, age, BTV serotypes, and strains within a serotype affect the clinical course of bluetongue. Results obtained indicate that in small ruminants, there is a marked difference in the susceptibility to clinical disease induced by BTV at the host species level but less so at the breed level. No major differences in virulence were found between divergent serotypes (BTV-8 and BTV-2). However, we observed striking differences in virulence between closely related strains of the same serotype collected toward the beginning and the end of the European BTV-8 outbreak. As observed previously, differences in disease severity were also observed when animals were infected with either blood from a BTV-infected animal or from the same virus isolated in cell culture. Interestingly, with the exception of two silent mutations, full viral genome sequencing showed identical consensus sequences of the virus before and after cell culture isolation. However, deep sequencing analysis revealed a marked decrease in the genetic diversity of the viral population after passaging in mammalian cells. In contrast, passaging in Culicoides cells increased the overall number of low-frequency variants compared to virus never passaged in cell culture. Thus, Culicoides might be a source of new viral variants, and viral population diversity can be another factor influencing BTV virulence. IMPORTANCE Bluetongue is one of the major infectious diseases of ruminants. It is caused by an arbovirus known as bluetongue virus (BTV). The clinical outcome of BTV infection is extremely variable. We show that there are clear links between the severity of bluetongue and the mammalian host species infected, while at the breed level differences were less evident. No differences were observed in the virulence of two different BTV serotypes (BTV-8 and BTV-2). In contrast, we show that the European BTV-8 strain isolated at the beginning of the bluetongue outbreak in 2006 was more virulent than a strain isolated toward the end of the outbreak. In addition, we show that there is a link between the variability of the BTV population as a whole and virulence, and our data also suggest that Culicoides cells might function as an “incubator” of viral variants.
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van der Sluijs MTW, de Smit AJ, Moormann RJM. Vector independent transmission of the vector-borne bluetongue virus. Crit Rev Microbiol 2014; 42:57-64. [PMID: 24645633 DOI: 10.3109/1040841x.2013.879850] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Bluetongue is an economically important disease of ruminants. The causative agent, Bluetongue virus (BTV), is mainly transmitted by insect vectors. This review focuses on vector-free BTV transmission, and its epizootic and economic consequences. Vector-free transmission can either be vertical, from dam to fetus, or horizontal via direct contract. For several BTV-serotypes, vertical (transplacental) transmission has been described, resulting in severe congenital malformations. Transplacental transmission had been mainly associated with live vaccine strains. Yet, the European BTV-8 strain demonstrated a high incidence of transplacental transmission in natural circumstances. The relevance of transplacental transmission for the epizootiology is considered limited, especially in enzootic areas. However, transplacental transmission can have a substantial economic impact due to the loss of progeny. Inactivated vaccines have demonstrated to prevent transplacental transmission. Vector-free horizontal transmission has also been demonstrated. Since direct horizontal transmission requires close contact of animals, it is considered only relevant for within-farm spreading of BTV. The genetic determinants which enable vector-free transmission are present in virus strains circulating in the field. More research into the genetic changes which enable vector-free transmission is essential to better evaluate the risks associated with outbreaks of new BTV serotypes and to design more appropriate control measures.
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Affiliation(s)
| | | | - Rob J M Moormann
- c Central Veterinary Institute , Lelystad , The Netherlands , and.,d Department of Infectious Diseases and Immunology, Virology Division , Utrecht University , Yalelaan , The Netherlands
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Coetzee P, van Vuuren M, Venter EH, Stokstad M. A review of experimental infections with bluetongue virus in the mammalian host. Virus Res 2014; 182:21-34. [PMID: 24462840 PMCID: PMC7132480 DOI: 10.1016/j.virusres.2013.12.044] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 12/27/2013] [Accepted: 12/31/2013] [Indexed: 11/23/2022]
Abstract
Experimental infection studies with bluetongue virus (BTV) in the mammalian host have a history that stretches back to the late 18th century. Studies in a wide range of ruminant and camelid species as well as mice have been instrumental in understanding BTV transmission, bluetongue (BT) pathogenicity/pathogenesis, viral virulence, the induced immune response, as well as reproductive failures associated with BTV infection. These studies have in many cases been complemented by in vitro studies with BTV in different cell types in tissue culture. Together these studies have formed the basis for the understanding of BTV-host interaction and have contributed to the design of successful control strategies, including the development of effective vaccines. This review describes some of the fundamental and contemporary infection studies that have been conducted with BTV in the mammalian host and provides an overview of the principal animal welfare issues that should be considered when designing experimental infection studies with BTV in in vivo infection models. Examples are provided from the authors' own laboratory where the three Rs (replacement, reduction and refinement) have been implemented in the design of experimental infection studies with BTV in mice and goats. The use of the ARRIVE guidelines for the reporting of data from animal infection studies is emphasized.
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Affiliation(s)
- Peter Coetzee
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa; Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, P. O. Box 8146 Dep., N-0033 Oslo, Norway.
| | - Moritz van Vuuren
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa.
| | - Estelle H Venter
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa.
| | - Maria Stokstad
- Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, P. O. Box 8146 Dep., N-0033 Oslo, Norway.
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van der Sluijs MTW, Schroer-Joosten DPH, Fid-Fourkour A, Vrijenhoek MP, Debyser I, Moulin V, Moormann RJM, de Smit AJ. Transplacental transmission of Bluetongue virus serotype 1 and serotype 8 in sheep: virological and pathological findings. PLoS One 2013; 8:e81429. [PMID: 24358112 PMCID: PMC3864790 DOI: 10.1371/journal.pone.0081429] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 10/13/2013] [Indexed: 11/24/2022] Open
Abstract
The Bluetongue virus serotype 8 (BTV-8) strain, which emerged in Europe in 2006, had an unusually high ability to cause foetal infection in pregnant ruminants. Other serotypes of BTV had already been present in Europe for more than a decade, but transplacental transmission of these strains had never been demonstrated. To determine whether transplacental transmission is a unique feature of BTV-8 we compared the incidence and pathological consequences of transplacental transmission of BTV-8 to that of BTV-1. Nine pregnant ewes were infected with either BTV-8 or BTV-1. The BTV strains used for the infection were field strains isolated on embryonated chicken eggs and passaged twice on mammalian cells. Blood samples were taken to monitor the viraemia in the ewes. Four weeks after the infection, the foetuses were examined for pathological changes and for the presence of BTV. BTV-8 could be demonstrated in 12 foetuses (43%) from 5 ewes (56%). %). BTV-1 was detected in 14 foetuses (82%) from 6 ewes (67%). Pathological changes were mainly found in the central nervous system. In the BTV-8 group, lympho-histiocytic infiltrates, gliosis and slight vacuolation of the neuropil were found. BTV-1infection induced a severe necrotizing encephalopathy and severe meningitis, with macroscopic hydranencephaly or porencephaly in 8 foetuses. In our experimental setting, using low passaged virus strains, BTV-1 was able to induce transplacental transmission to a higher incidence compared to BTV-8, causing more severe pathology.
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Affiliation(s)
| | | | | | - Mieke P Vrijenhoek
- Animal Services and Pathology, MSD Animal Health, Boxmeer, The Netherlands
| | - Isolde Debyser
- CoVeToP, Consultancy in Veterinary and Toxicological Pathology, Enghien, Belgium
| | - Véronique Moulin
- Research and Development, MSD Animal Health, Boxmeer, The Netherlands
| | - Rob J M Moormann
- Central Veterinary Institute, Animal Sciences Group, Wageningen University and Research centre, Lelystad, The Netherlands ; Department of Infectious Diseases and Immunology, Virology Division, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Abraham J de Smit
- Research and Development, MSD Animal Health, Boxmeer, The Netherlands
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The evolution of bluetongue virus: genetic and phenotypic diversity of field strains. Pol J Vet Sci 2013; 16:611-6. [PMID: 24195303 DOI: 10.2478/pjvs-2013-0086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bluetongue virus (BTV), the aetiological agent of bluetongue (BT), is a small (about 70 nm in diameter) icosahedral virus with a genome composed of ten linear segments of double-stranded RNA (dsRNA), which is packaged within an icosahedral nucleocapsid composed of seven structural proteins. The BTV genome evolves rapidly via genetic drift, reassortment of genome segments (genetic shift) and intragenic recombination. This evolution, and random fixation of quasispecies variants during transmission of BTV between susceptible animals and vectors appear to be the main mechanism leading to the observed genetic diversity amongst BTV field strains. The individual BTV gene segments evolve independently of one another by genetic drift in a host-specific fashion, generating quasispecies populations in both ruminant and insect hosts. Reassortment of BTV genes is responsible for genetic shift among strains of BTV, and has been demonstrated after infection of either the ruminant host or insect vector with different strains or serotypes of BTV. Intragenetic recombination, whereby mosaic genes are generated from the "splicing" together of homologous genes from different ancestral viral strains, has been demonstrated for BTV. The genetic variation of BTV is likely responsible for differences in the virulence and other phenotypic properties of individual field strains of the virus.
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Maclachlan NJ, Mayo CE. Potential strategies for control of bluetongue, a globally emerging, Culicoides-transmitted viral disease of ruminant livestock and wildlife. Antiviral Res 2013; 99:79-90. [DOI: 10.1016/j.antiviral.2013.04.021] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 04/25/2013] [Accepted: 04/30/2013] [Indexed: 11/16/2022]
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36
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Jabbar TK, Calvo-Pinilla E, Mateos F, Gubbins S, Bin-Tarif A, Bachanek-Bankowska K, Alpar O, Ortego J, Takamatsu HH, Mertens PPC, Castillo-Olivares J. Protection of IFNAR (-/-) mice against bluetongue virus serotype 8, by heterologous (DNA/rMVA) and homologous (rMVA/rMVA) vaccination, expressing outer-capsid protein VP2. PLoS One 2013; 8:e60574. [PMID: 23593251 PMCID: PMC3625202 DOI: 10.1371/journal.pone.0060574] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/28/2013] [Indexed: 01/21/2023] Open
Abstract
The protective efficacy of recombinant vaccines expressing serotype 8 bluetongue virus (BTV-8) capsid proteins was tested in a mouse model. The recombinant vaccines comprised plasmid DNA or Modified Vaccinia Ankara viruses encoding BTV VP2, VP5 or VP7 proteins. These constructs were administered alone or in combination using either a homologous prime boost vaccination regime (rMVA/rMVA) or a heterologous vaccination regime (DNA/rMVA). The DNA/rMVA or rMVA/rMVA prime-boost were administered at a three week interval and all of the animals that received VP2 generated neutralising antibodies. The vaccinated and non-vaccinated-control mice were subsequently challenged with a lethal dose of BTV-8. Mice vaccinated with VP7 alone were not protected. However, mice vaccinated with DNA/rMVA or rMVA/rMVA expressing VP2, VP5 and VP7 or VP2 alone were all protected.
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Affiliation(s)
| | | | - Francisco Mateos
- Centro en Investigación y Sanidad Animal, Valdeolmos, Madrid, Spain
| | - Simon Gubbins
- The Pirbright Institute, Pirbright, Woking, Surrey, United Kingdom
| | | | | | - Oya Alpar
- Centre for Drug Delivery Research, London School of Pharmacy, London, United Kingdom
| | - Javier Ortego
- Centro en Investigación y Sanidad Animal, Valdeolmos, Madrid, Spain
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37
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Wang WS, Sun EC, Xu QY, Yang T, Qin YL, Zhao J, Feng YF, Li JP, Wei P, Zhang CY, Wu DL. Identification of two novel BTV16-specific B cell epitopes using monoclonal antibodies against the VP2 protein. Appl Microbiol Biotechnol 2013; 97:5933-42. [DOI: 10.1007/s00253-013-4779-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 02/12/2013] [Accepted: 02/13/2013] [Indexed: 11/29/2022]
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38
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Legisa D, Gonzalez F, De Stefano G, Pereda A, Santos MJD. Phylogenetic analysis of bluetongue virus serotype 4 field isolates from Argentina. J Gen Virol 2013; 94:652-662. [DOI: 10.1099/vir.0.046896-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bluetongue is an insect-transmitted viral disease of ruminant species, which represents a major barrier to the international trade of animals and their products. Bluetongue virus (BTV) has a genome composed of ten linear segments of dsRNA, which code for at least ten different viral proteins. In South America, serological evidence for the presence of BTV has been found in Peru, Argentina, Brazil, Ecuador and Chile. Brazil and Argentina are the only South American countries where BTV has been isolated. In Brazil, only one BTV isolate, serotype 12, has been reported, whereas in Argentina five BTV serotype 4 isolates have been obtained from cattle without clinical signs. Three of these five isolates were isolated during 1999–2001, whereas two of them were obtained as part of the present work. This study describes sequence comparisons and phylogenetic analyses of segment (Seg)-2, Seg-3, Seg-6, Seg-7 and Seg-10 of the first Argentinian field isolates of BTV. The analysis of Seg-2 and Seg-6 resulted in a single cluster of Argentinian sequences into the serotype 4 clade. In addition, the Argentinian sequences grouped within the nucleotype A clade, along with reference strains. The analysis of Seg-3, Seg-7 and Seg-10 showed that the Argentinian isolates grouped into the western topotype, indicating that the circulating virus had an African/European origin. Phylogenetic analysis revealed that the Argentinian sequences present a South American genetic identity, suggesting an independent lineage evolution.
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Affiliation(s)
- D. Legisa
- Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina
| | - F. Gonzalez
- Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina
| | - G. De Stefano
- Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina
| | - A. Pereda
- Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina
| | - M. J. Dus Santos
- Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina
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39
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Coetzee P, Van Vuuren M, Stokstad M, Myrmel M, Venter EH. Bluetongue virus genetic and phenotypic diversity: towards identifying the molecular determinants that influence virulence and transmission potential. Vet Microbiol 2012; 161:1-12. [PMID: 22835527 DOI: 10.1016/j.vetmic.2012.07.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Revised: 06/22/2012] [Accepted: 07/02/2012] [Indexed: 12/23/2022]
Abstract
Bluetongue virus (BTV) is the prototype member of the Orbivirus genus in the family Reoviridae and is the aetiological agent of the arthropod transmitted disease bluetongue (BT) that affects both ruminant and camelid species. The disease is of significant global importance due to its economic impact and effect on animal welfare. Bluetongue virus, a dsRNA virus, evolves through a process of quasispecies evolution that is driven by genetic drift and shift as well as intragenic recombination. Quasispecies evolution coupled with founder effect and evolutionary selective pressures has over time led to the establishment of genetically distinct strains of the virus in different epidemiological systems throughout the world. Bluetongue virus field strains may differ substantially from each other with regards to their phenotypic properties (i.e. virulence and/or transmission potential). The intrinsic molecular determinants that influence the phenotype of BTV have not clearly been characterized. It is currently unclear what contribution each of the viral genome segments have in determining the phenotypic properties of the virus and it is also unknown how genetic variability in the individual viral genes and their functional domains relate to differences in phenotype. In order to understand how genetic variation in particular viral genes could potentially influence the phenotypic properties of the virus; a closer understanding of the BTV virion, its encoded proteins and the evolutionary mechanisms that shape the diversity of the virus is required. This review provides a synopsis of these issues and highlights some of the studies that have been conducted on BTV and the closely related African horse sickness virus (AHSV) that have contributed to ongoing attempts to identify the molecular determinants that influence the virus' phenotype. Different strategies that can be used to generate BTV mutants in vitro and methods through which the causality between particular genetic modifications and changes in phenotype may be determined are also described. Finally examples are highlighted where a clear understanding of the molecular determinants that influence the phenotype of the virus may have contributed to risk assessment and mitigation strategies during recent outbreaks of BT in Europe.
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Affiliation(s)
- Peter Coetzee
- Department of Veterinary Tropical Diseases, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria, 0110, South Africa.
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40
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The combination of abundance and infection rates of Culicoides sonorensis estimates risk of subsequent bluetongue virus infection of sentinel cattle on California dairy farms. Vet Parasitol 2012; 187:295-301. [DOI: 10.1016/j.vetpar.2012.01.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 12/30/2011] [Accepted: 01/02/2012] [Indexed: 11/20/2022]
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41
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Brackney DE, Brown IK, Nofchissey RA, Fitzpatrick KA, Ebel GD. Homogeneity of Powassan virus populations in naturally infected Ixodes scapularis. Virology 2010; 402:366-71. [PMID: 20434750 DOI: 10.1016/j.virol.2010.03.035] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Revised: 12/02/2009] [Accepted: 03/23/2010] [Indexed: 12/22/2022]
Abstract
Powassan virus (POWV, Flaviviridae: Flavivirus) is the sole North American member of the tick-borne encephalitis complex and consists of two distinct lineages that are maintained in ecologically discrete enzootic transmission cycles. The underlying genetic mechanisms that lead to niche partitioning in arboviruses are poorly understood. Therefore, intra- and interhost genetic diversity was analyzed to determine if POWV exists as a quasispecies in nature and quantify selective pressures within and between hosts. In contrast to previous reports for West Nile virus (WNV), significant intrahost genetic diversity was not observed. However, pN (0.238) and d(N)/d(S) ratios (0.092) for interhost diversity were similar to those of WNV. Combined, these data suggest that purifying selection and/or population bottlenecks constrain quasispecies diversity within ticks. These same selective and stochastic mechanisms appear to drive minor sequence changes between ticks. Moreover, Powassan virus populations seem not to be structured as quasispecies in naturally infected adult deer ticks.
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Affiliation(s)
- Doug E Brackney
- University of New Mexico School of Medicine, Department of Pathology, Albuquerque, New Mexico, USA
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42
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The Evolutionary Dynamics of Bluetongue Virus. J Mol Evol 2010; 70:583-92. [DOI: 10.1007/s00239-010-9354-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 05/17/2010] [Indexed: 12/01/2022]
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43
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Maclachlan NJ, Guthrie AJ. Re-emergence of bluetongue, African horse sickness, and other orbivirus diseases. Vet Res 2010; 41:35. [PMID: 20167199 PMCID: PMC2826768 DOI: 10.1051/vetres/2010007] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 01/25/2010] [Indexed: 11/14/2022] Open
Abstract
Arthropod-transmitted viruses (Arboviruses) are important causes of disease in humans and animals, and it is proposed that climate change will increase the distribution and severity of arboviral diseases. Orbiviruses are the cause of important and apparently emerging arboviral diseases of livestock, including bluetongue virus (BTV), African horse sickness virus (AHSV), equine encephalosis virus (EEV), and epizootic hemorrhagic disease virus (EHDV) that are all transmitted by haematophagous Culicoides insects. Recent changes in the global distribution and nature of BTV infection have been especially dramatic, with spread of multiple serotypes of the virus throughout extensive portions of Europe and invasion of the south-eastern USA with previously exotic virus serotypes. Although climate change has been incriminated in the emergence of BTV infection of ungulates, the precise role of anthropogenic factors and the like is less certain. Similarly, although there have been somewhat less dramatic recent alterations in the distribution of EHDV, AHSV, and EEV, it is not yet clear what the future holds in terms of these diseases, nor of other potentially important but poorly characterized Orbiviruses such as Peruvian horse sickness virus.
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Affiliation(s)
- N James Maclachlan
- Department of Pathology, Microbiology and Immunology, University of California, Davis, CA 95616, USA.
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44
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Kobayashi Y, Suzuki Y, Itou T, Carvalho AAB, Cunha EMS, Ito FH, Gojobori T, Sakai T. Low genetic diversities of rabies virus populations within different hosts in Brazil. INFECTION GENETICS AND EVOLUTION 2009; 10:278-83. [PMID: 20018256 DOI: 10.1016/j.meegid.2009.12.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Revised: 12/03/2009] [Accepted: 12/05/2009] [Indexed: 01/21/2023]
Abstract
The low rates of nonsynonymous evolution observed in natural rabies virus (RABV) isolates are suggested to have arisen in association with the structural and functional constraints operating on the virus protein and the infection strategies employed by RABV within infected hosts to avoid strong selection by the immune response. In order to investigate the relationship between the genetic characteristics of RABV populations within hosts and the virus evolution, the present study examined the genetic heterogeneities of RABV populations within naturally infected dogs and foxes in Brazil, as well as those of bat RABV populations that were passaged once in suckling mice. Sequence analyses of complete RABV glycoprotein (G) genes showed that RABV populations within infected hosts were genetically highly homogeneous whether they were infected naturally or experimentally (nucleotide diversities of 0-0.95x10(-3)). In addition, amino acid mutations were randomly distributed over the entire region of the G protein, and the nonsynonymous/synonymous rate ratios (d(N)/d(S)) for the G protein gene were less than 1. These findings suggest that the low genetic diversities of RABV populations within hosts reflect the stabilizing selection operating on the virus, the infection strategies of the virus, and eventually, the evolutionary patterns of the virus.
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Affiliation(s)
- Yuki Kobayashi
- Nihon University Veterinary Research Center, 1866 Kameino, Fujisawa, Kanagawa 252-8510, Japan
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45
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Clavijo G, Williams T, Muñoz D, Caballero P, López-Ferber M. Mixed genotype transmission bodies and virions contribute to the maintenance of diversity in an insect virus. Proc Biol Sci 2009; 277:943-51. [PMID: 19939845 DOI: 10.1098/rspb.2009.1838] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
An insect nucleopolyhedrovirus naturally survives as a mixture of at least nine genotypes. Infection by multiple genotypes results in the production of virus occlusion bodies (OBs) with greater pathogenicity than those of any genotype alone. We tested the hypothesis that each OB contains a genotypically diverse population of virions. Few insects died following inoculation with an experimental two-genotype mixture at a dose of one OB per insect, but a high proportion of multiple infections were observed (50%), which differed significantly from the frequencies predicted by a non-associated transmission model in which genotypes are segregated into distinct OBs. By contrast, insects that consumed multiple OBs experienced higher mortality and infection frequencies did not differ significantly from those of the non-associated model. Inoculation with genotypically complex wild-type OBs indicated that genotypes tend to be transmitted in association, rather than as independent entities, irrespective of dose. To examine the hypothesis that virions may themselves be genotypically heterogeneous, cell culture plaques derived from individual virions were analysed to reveal that one-third of virions was of mixed genotype, irrespective of the genotypic composition of the OBs. We conclude that co-occlusion of genotypically distinct virions in each OB is an adaptive mechanism that favours the maintenance of virus diversity during insect-to-insect transmission.
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Affiliation(s)
- Gabriel Clavijo
- Laboratorio de Entomología Agrícola y Patología de Insectos, Departamento de Producción Agraria, Universidad Pública de Navarra, Pamplona, Spain
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46
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Sugaya T, Mori K, Nishioka T, Masuma S, Oka M, Mushiake K, Okinaka Y, Nakai T. Genetic heterogeneity of betanodaviruses in juvenile production trials of Pacific bluefin tuna, Thunnus orientalis (Temminck & Schlegel). JOURNAL OF FISH DISEASES 2009; 32:815-823. [PMID: 19538459 DOI: 10.1111/j.1365-2761.2009.01057.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Pacific bluefin tuna, Thunnus orientalis (Temminck & Schlegel), is one of the most important commercially exploited fish species in the world, and juvenile production techniques have been developed for its culture and stock enhancement in Japan. However, recent juvenile production has often failed because of the occurrence of viral nervous necrosis caused by betanodaviruses. In this study, we examined the genetic variability of betanodaviruses detected in the diseased juveniles to understand the transmission of the disease in a tuna hatchery. A total of 94 nucleotide sequences of betanodavirus (partial sequence of the coat protein gene, RNA2) were obtained from fish samples by reverse-transcriptase polymerase chain reaction amplification and 13 haplotypes were recognized among the sequences. The haplotype distributions in the viral populations from the diseased juveniles were related to the broodstocks from which the juveniles originated, suggesting that vertical transmission had occurred in the hatchery. The statistical parsimony network of viral haplotypes suggests that the nucleotide substitutions among the samples were accumulated in a recent population growth.
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Affiliation(s)
- T Sugaya
- Stock Enhancement Technology Development Center, National Research Institute of Aquaculture, Fisheries Research Agency, Saiki, Oita, Japan.
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47
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Nomikou K, Dovas CΙ, Maan S, Anthony SJ, Samuel AR, Papanastassopoulou M, Maan NS, Mangana O, Mertens PPC. Evolution and phylogenetic analysis of full-length VP3 genes of Eastern Mediterranean bluetongue virus isolates. PLoS One 2009; 4:e6437. [PMID: 19649272 PMCID: PMC2713410 DOI: 10.1371/journal.pone.0006437] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Accepted: 05/02/2009] [Indexed: 11/19/2022] Open
Abstract
Bluetongue virus (BTV) is the ‘type’ species of the genus Orbivirus within the family Reoviridae. The BTV genome is composed of ten linear segments of double-stranded RNA (dsRNA), each of which codes for one of ten distinct viral proteins. Previous phylogenetic comparisons have evaluated variations in genome segment 3 (Seg-3) nucleotide sequence as way to identify the geographical origin (different topotypes) of BTV isolates. The full-length nucleotide sequence of genome Seg-3 was determined for thirty BTV isolates recovered in the eastern Mediterranean region, the Balkans and other geographic areas (Spain, India, Malaysia and Africa). These data were compared, based on molecular variability, positive-selection-analysis and maximum-likelihood phylogenetic reconstructions (using appropriate substitution models) to 24 previously published sequences, revealing their evolutionary relationships. These analyses indicate that negative selection is a major force in the evolution of BTV, restricting nucleotide variability, reducing the evolutionary rate of Seg-3 and potentially of other regions of the BTV genome. Phylogenetic analysis of the BTV-4 strains isolated over a relatively long time interval (1979–2000), in a single geographic area (Greece), showed a low level of nucleotide diversity, indicating that the virus can circulate almost unchanged for many years. These analyses also show that the recent incursions into south-eastern Europe were caused by BTV strains belonging to two different major-lineages: representing an ‘eastern’ (BTV-9, -16 and -1) and a ‘western’ (BTV-4) group/topotype. Epidemiological and phylogenetic analyses indicate that these viruses originated from a geographic area to the east and southeast of Greece (including Cyprus and the Middle East), which appears to represent an important ecological niche for the virus that is likely to represent a continuing source of future BTV incursions into Europe.
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Affiliation(s)
- Kyriaki Nomikou
- Arbovirus Molecular Research Group, Department of vector borne diseases, Institute for Animal Health, Pirbright Laboratory, Woking, Surrey, United Kingdom
- Virus Laboratory, Institute of Infectious and Parasitic Diseases, Ministry of Rural Development and Food, Athens, Greece
| | - Chrysostomos Ι. Dovas
- Department of Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Sushila Maan
- Arbovirus Molecular Research Group, Department of vector borne diseases, Institute for Animal Health, Pirbright Laboratory, Woking, Surrey, United Kingdom
| | - Simon J. Anthony
- Wildlife Disease Laboratory, San Diego Zoo Conservation Research, Escondido, California, United States of America
| | - Alan R. Samuel
- Arbovirus Molecular Research Group, Department of vector borne diseases, Institute for Animal Health, Pirbright Laboratory, Woking, Surrey, United Kingdom
| | - Maria Papanastassopoulou
- Department of Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Narender S. Maan
- Arbovirus Molecular Research Group, Department of vector borne diseases, Institute for Animal Health, Pirbright Laboratory, Woking, Surrey, United Kingdom
| | - Olga Mangana
- Virus Laboratory, Institute of Infectious and Parasitic Diseases, Ministry of Rural Development and Food, Athens, Greece
| | - Peter P. C. Mertens
- Arbovirus Molecular Research Group, Department of vector borne diseases, Institute for Animal Health, Pirbright Laboratory, Woking, Surrey, United Kingdom
- * E-mail:
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48
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Anthony SJ, Maan N, Maan S, Sutton G, Attoui H, Mertens PPC. Genetic and phylogenetic analysis of the core proteins VP1, VP3, VP4, VP6 and VP7 of epizootic haemorrhagic disease virus (EHDV). Virus Res 2009; 145:187-99. [PMID: 19632280 DOI: 10.1016/j.virusres.2009.07.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 07/15/2009] [Accepted: 07/16/2009] [Indexed: 11/29/2022]
Abstract
The core proteins of epizootic haemorrhagic disease virus (EHDV) have important roles to perform in maintaining the structure and function of the virus. A complete genetic and phylogenetic analysis was therefore performed on these proteins (and the genes that code for them) to allow comparison of the selective pressures acting on each. Accession numbers, gene and protein sizes, ORF positions, G+C contents, terminal hexanucleotides, start and stop codons and phylogenetic relationships are all presented. The inner core proteins (VP1, VP3, VP4 and VP6) were characterised by high levels of sequence conservation, and the ability to topotype isolates very strongly into eastern or western groups. This is particularly evident in genome segment 9 (VP6) which exists as two different sized homologues. VP7 did not topotype, but rather exhibited a more random, radial phylogeny suggestive of genetic drift. With the exception of VP6, all of the core proteins also showed high numbers of synonymous mutations in the third base position, suggesting they have been evolving for a long period of time. Interestingly, VP6 did not show this, and possible reasons for this are discussed.
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Affiliation(s)
- S J Anthony
- Vector-borne Diseases Program, Institute for Animal Health, Ash Road, Pirbright, Surrey GU24 0NF, United Kingdom.
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49
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Maclachlan N, Drew C, Darpel K, Worwa G. The Pathology and Pathogenesis of Bluetongue. J Comp Pathol 2009; 141:1-16. [DOI: 10.1016/j.jcpa.2009.04.003] [Citation(s) in RCA: 317] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 04/09/2009] [Accepted: 04/20/2009] [Indexed: 11/16/2022]
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50
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Dal Pozzo F, Saegerman C, Thiry E. Bovine infection with bluetongue virus with special emphasis on European serotype 8. Vet J 2009; 182:142-51. [PMID: 19477665 DOI: 10.1016/j.tvjl.2009.05.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 03/26/2009] [Accepted: 05/01/2009] [Indexed: 11/28/2022]
Abstract
Bluetongue virus (BTV) is an arthropod-borne virus infecting domestic and wild ruminants. Infection in cattle is commonly asymptomatic and characterised by a long viraemia. Associated with the emergence and the recrudescence of BTV serotype 8 (BTV-8) in Northern and Central Europe, remarkable differences have been noticed in the transmission and in the clinical expression of the disease, with cattle showing clinical illness and reproductive disorders such as abortion, stillbirth and fetal abnormalities. Several investigations have already indicated the putative ability of the European BTV-8 strain to cross the bovine placenta and to cause congenital infections. The current epidemiological and pathological findings present an unusual picture of the disease in affected bovines.
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Affiliation(s)
- Fabiana Dal Pozzo
- Department of Infectious and Parasitic Diseases, Virology and Viral Diseases, Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium
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