1
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Zhao Z, Xie Y, Bai B, Luo C, Zhou J, Li W, Meng Y, Li L, Li D, Li X, Li X, Wang X, Sun J, Xu Z, Sun Y, Zhang W, Fan Z, Zhao X, Wu L, Ma J, Li OY, Shang G, Chai Y, Liu K, Wang P, Gao GF, Qi J. Structural basis for receptor binding and broader interspecies receptor recognition of currently circulating Omicron sub-variants. Nat Commun 2023; 14:4405. [PMID: 37479708 PMCID: PMC10362042 DOI: 10.1038/s41467-023-39942-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 06/29/2023] [Indexed: 07/23/2023] Open
Abstract
Multiple SARS-CoV-2 Omicron sub-variants, such as BA.2, BA.2.12.1, BA.4, and BA.5, emerge one after another. BA.5 has become the dominant strain worldwide. Additionally, BA.2.75 is significantly increasing in some countries. Exploring their receptor binding and interspecies transmission risk is urgently needed. Herein, we examine the binding capacities of human and other 28 animal ACE2 orthologs covering nine orders towards S proteins of these sub-variants. The binding affinities between hACE2 and these sub-variants remain in the range as that of previous variants of concerns (VOCs) or interests (VOIs). Notably, R493Q reverse mutation enhances the bindings towards ACE2s from humans and many animals closely related to human life, suggesting an increased risk of cross-species transmission. Structures of S/hACE2 or RBD/hACE2 complexes for these sub-variants and BA.2 S binding to ACE2 of mouse, rat or golden hamster are determined to reveal the molecular basis for receptor binding and broader interspecies recognition.
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Affiliation(s)
- Zhennan Zhao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yufeng Xie
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing, China
| | - Bin Bai
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chunliang Luo
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong, China
| | - Jingya Zhou
- University of Chinese Academy of Sciences, Beijing, China
- Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Weiwei Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yumin Meng
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Linjie Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Dedong Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xiaomei Li
- Shanxi Academy of Advanced Research and Innovation, Taiyuan, China
| | - Xiaoxiong Li
- Shanxi Academy of Advanced Research and Innovation, Taiyuan, China
| | - Xiaoyun Wang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Junqing Sun
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong, China
| | - Zepeng Xu
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Faculty of Health Sciences, University of Macau, Macau, China
| | - Yeping Sun
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Wei Zhang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Zheng Fan
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xin Zhao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Linhuan Wu
- Chinese National Microbiology Data Center (NMDC), Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Juncai Ma
- Chinese National Microbiology Data Center (NMDC), Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Odel Y Li
- NHC Key Laboratory of Parasite and Vector Biology, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Guijun Shang
- Shanxi Academy of Advanced Research and Innovation, Taiyuan, China
| | - Yan Chai
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Kefang Liu
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
| | - Peiyi Wang
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, China.
| | - George F Gao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China.
| | - Jianxun Qi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Beijing Life Science Academy, Beijing, China.
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2
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Li L, Liao H, Meng Y, Li W, Han P, Liu K, Wang Q, Li D, Zhang Y, Wang L, Fan Z, Zhang Y, Wang Q, Zhao X, Sun Y, Huang N, Qi J, Gao GF. Structural basis of human ACE2 higher binding affinity to currently circulating Omicron SARS-CoV-2 sub-variants BA.2 and BA.1.1. Cell 2022; 185:2952-2960.e10. [PMID: 35809570 PMCID: PMC9212699 DOI: 10.1016/j.cell.2022.06.023] [Citation(s) in RCA: 80] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/15/2022] [Accepted: 06/09/2022] [Indexed: 02/06/2023]
Abstract
The currently circulating Omicron sub-variants are the SARS-CoV-2 strains with the highest number of known mutations. Herein, we found that human angiotensin-converting enzyme 2 (hACE2) binding affinity to the receptor-binding domains (RBDs) of the four early Omicron sub-variants (BA.1, BA.1.1, BA.2, and BA.3) follows the order BA.1.1 > BA.2 > BA.3 ≈ BA.1. The complex structures of hACE2 with RBDs of BA.1.1, BA.2, and BA.3 reveal that the higher hACE2 binding affinity of BA.2 than BA.1 is related to the absence of the G496S mutation in BA.2. The R346K mutation in BA.1.1 majorly affects the interaction network in the BA.1.1 RBD/hACE2 interface through long-range alterations and contributes to the higher hACE2 affinity of the BA.1.1 RBD than the BA.1 RBD. These results reveal the structural basis for the distinct hACE2 binding patterns among BA.1.1, BA.2, and BA.3 RBDs.
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Affiliation(s)
- Linjie Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hanyi Liao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yumin Meng
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiwei Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pengcheng Han
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; School of Medicine, Zhongda Hospital, Southeast University, Nanjing 210009, China
| | - Kefang Liu
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qing Wang
- National Institute of Biological Sciences, No. 7 Science Park Road, Zhongguancun Life Science Park, Beijing 102206, China
| | - Dedong Li
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yanfang Zhang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Liang Wang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zheng Fan
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yuqin Zhang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qiyue Wang
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xin Zhao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Yeping Sun
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Niu Huang
- National Institute of Biological Sciences, No. 7 Science Park Road, Zhongguancun Life Science Park, Beijing 102206, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 102206, China.
| | - Jianxun Qi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - George Fu Gao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Comparison of Endemic and Epidemic Vesicular Stomatitis Virus Lineages in Culicoides sonorensis Midges. Viruses 2022; 14:v14061221. [PMID: 35746691 PMCID: PMC9230599 DOI: 10.3390/v14061221] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 02/04/2023] Open
Abstract
Vesicular stomatitis virus (VSV) primarily infects livestock and is transmitted by direct contact and vectored by Culicoides midges (Diptera: Ceratopogonidae). Endemic to Central and South America, specific VSV lineages spread northward out of endemic regions of Mexico and into the U.S. sporadically every five to ten years. In 2012, a monophyletic epidemic lineage 1.1 successfully spread northward into the U.S. In contrast, the closest endemic ancestor, lineage 1.2, remained circulating exclusively in endemic regions in Mexico. It is not clear what roles virus-animal interactions and/or virus-vector interactions play in the ability of specific viral lineages to escape endemic regions in Mexico and successfully cause outbreaks in the U.S., nor the genetic basis for such incursions. Whole-genome sequencing of epidemic VSV 1.1 and endemic VSV 1.2 revealed significant differences in just seven amino acids. Previous studies in swine showed that VSV 1.1 was more virulent than VSV 1.2. Here, we compared the efficiency of these two viral lineages to infect the vector Culicoides sonorensis (Wirth and Jones) and disseminate to salivary glands for subsequent transmission. Our results showed that midges orally infected with the epidemic VSV 1.1 lineage had significantly higher infection dissemination rates compared to those infected with the endemic VSV 1.2 lineage. Thus, in addition to affecting virus-animal interactions, as seen with higher virulence in pigs, small genetic changes may also affect virus-vector interactions, contributing to the ability of specific viral lineages to escape endemic regions via vector-borne transmission.
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4
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Phylodynamics of Alagoas vesiculovirus in Brazil. Braz J Microbiol 2022; 53:1691-1699. [PMID: 35553417 PMCID: PMC9433616 DOI: 10.1007/s42770-022-00756-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 04/10/2022] [Indexed: 11/02/2022] Open
Abstract
The vesicular stomatitis virus belongs to the Rhabdoviridae family, genus Vesiculovirus. Four species (New Jersey, Indiana, Cocal, and Alagoas) are responsible for disease outbreaks in Western Hemisphere countries. In Brazil, the Alagoas virus is responsible for the main outbreaks of the disease, mainly in the states of the Northeast, Midwest, and Southeast regions of the country. The present study aimed to perform the genetic characterization of 41 vesicular stomatitis virus samples. RNA was extracted using Trizol and used to amplify part of gene P. Amplicons were sequenced using the Sanger method. The phylogenetic trees generated showed that Alagoas vesiculoviruses were positioned into three groups: group A formed by the first virus isolate; group B by isolates from states in the Northeast region; and group C by isolates from the states of Bahia, Goiás, and Tocantins. Their divergence to date has generated the formation of two genotypes evolving independently in regions that until the present study had little geographic overlap.
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5
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Hole K, Nfon C, Rodriguez LL, Velazquez-Salinas L. A Multiplex Real-Time Reverse Transcription Polymerase Chain Reaction Assay With Enhanced Capacity to Detect Vesicular Stomatitis Viral Lineages of Central American Origin. Front Vet Sci 2022; 8:783198. [PMID: 34988142 PMCID: PMC8720762 DOI: 10.3389/fvets.2021.783198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 12/01/2021] [Indexed: 11/13/2022] Open
Abstract
Vesicular stomatitis virus (VSV) causes a disease in susceptible livestock that is clinically indistinguishable from foot-and-mouth disease. Rapid testing is therefore critical to identify VSV and rule out FMD. We previously developed and validated a multiplex real-time reverse transcription polymerase chain reaction assay (mRRT-PCR) for detection of both VS New Jersey virus (VSNJV) and VS Indiana virus (VSIV). However, it was subsequently apparent that this assay failed to detect some VSNJV isolates in Mexico, especially in genetic group II, lineage 2.1. In order to enhance the sensitivity of the mRRT-PCR for VSNJV, parts of the assay were redesigned and revalidated using new and improved PCR chemistries. The redesign markedly improved the assay by increasing the VSNJV detection sensitivity of lineage 2.1 and thereby allowing detection of all VSNJV clades. The new assay showed an increased capability to detect VSNJV. Specifically, the new mRRT-PCR detected VSNJV in 100% (87/87) of samples from Mexico in 2006-2007 compared to 74% for the previous mRRT-PCR. Furthermore, the analytical sensitivity of the new mRRT-PCR was enhanced for VSNJV. Importantly, the modified assay had the same sensitivity and specificity for VSIV as the previously published assay. Our results highlight the challenges the large genetic variability of VSV pose for virus detection by mRRT-PCR and show the importance of frequent re-evaluation and validation of diagnostic assays for VSV to ensure high sensitivity and specificity.
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Affiliation(s)
- Kate Hole
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada
| | - Charles Nfon
- National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada
| | - Luis L Rodriguez
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, United States Department of Agriculture-Agricultural Research Service, Greenport, NY, United States
| | - Lauro Velazquez-Salinas
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, United States Department of Agriculture-Agricultural Research Service, Greenport, NY, United States
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6
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Molecular insights into receptor binding of recent emerging SARS-CoV-2 variants. Nat Commun 2021; 12:6103. [PMID: 34671049 PMCID: PMC8528823 DOI: 10.1038/s41467-021-26401-w] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/30/2021] [Indexed: 01/09/2023] Open
Abstract
Multiple SARS-CoV-2 variants of concern (VOCs) have been emerging and some have been linked to an increase in case numbers globally. However, there is yet a lack of understanding of the molecular basis for the interactions between the human ACE2 (hACE2) receptor and these VOCs. Here we examined several VOCs including Alpha, Beta, and Gamma, and demonstrate that five variants receptor-binding domain (RBD) increased binding affinity for hACE2, and four variants pseudoviruses increased entry into susceptible cells. Crystal structures of hACE2-RBD complexes help identify the key residues facilitating changes in hACE2 binding affinity. Additionally, soluble hACE2 protein efficiently prevent most of the variants pseudoviruses. Our findings provide important molecular information and may help the development of novel therapeutic and prophylactic agents targeting these emerging mutants.
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7
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Surveillance along the Rio Grande during the 2020 Vesicular Stomatitis Outbreak Reveals Spatio-Temporal Dynamics of and Viral RNA Detection in Black Flies. Pathogens 2021; 10:pathogens10101264. [PMID: 34684213 PMCID: PMC8541391 DOI: 10.3390/pathogens10101264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 11/26/2022] Open
Abstract
Vesicular stomatitis virus (VSV) emerges periodically from its focus of endemic transmission in southern Mexico to cause epizootics in livestock in the US. The ecology of VSV involves a diverse, but largely undefined, repertoire of potential reservoir hosts and invertebrate vectors. As part of a larger program to decipher VSV transmission, we conducted a study of the spatiotemporal dynamics of Simulium black flies, a known vector of VSV, along the Rio Grande in southern New Mexico, USA from March to December 2020. Serendipitously, the index case of VSV-Indiana (VSIV) in the USA in 2020 occurred at a central point of our study. Black flies appeared soon after the release of the Rio Grande’s water from an upstream dam in March 2020. Two-month and one-year lagged precipitation, maximum temperature, and vegetation greenness, measured as Normalized Difference Vegetation Index (NDVI), were associated with increased black fly abundance. We detected VSIV RNA in 11 pools comprising five black fly species using rRT-PCR; five pools yielded a VSIV sequence. To our knowledge, this is the first detection of VSV in the western US from vectors that were not collected on premises with infected domestic animals.
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8
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McGregor BL, Rozo-Lopez P, Davis TM, Drolet BS. Detection of Vesicular Stomatitis Virus Indiana from Insects Collected during the 2020 Outbreak in Kansas, USA. Pathogens 2021; 10:1126. [PMID: 34578160 PMCID: PMC8471201 DOI: 10.3390/pathogens10091126] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/25/2021] [Accepted: 08/30/2021] [Indexed: 01/20/2023] Open
Abstract
Vesicular stomatitis (VS) is a reportable viral disease which affects horses, cattle, and pigs in the Americas. Outbreaks of vesicular stomatitis virus New Jersey serotype (VSV-NJ) in the United States typically occur on a 5-10-year cycle, usually affecting western and southwestern states. In 2019-2020, an outbreak of VSV Indiana serotype (VSV-IN) extended eastward into the states of Kansas and Missouri for the first time in several decades, leading to 101 confirmed premises in Kansas and 37 confirmed premises in Missouri. In order to investigate which vector species contributed to the outbreak in Kansas, we conducted insect surveillance at two farms that experienced confirmed VSV-positive cases, one each in Riley County and Franklin County. Centers for Disease Control and Prevention miniature light traps were used to collect biting flies on the premises. Two genera of known VSV vectors, Culicoides biting midges and Simulium black flies, were identified to species, pooled by species, sex, reproductive status, and collection site, and tested for the presence of VSV-IN RNA by RT-qPCR. In total, eight positive pools were detected from Culicoides sonorensis (1), Culicoides stellifer (3), Culicoides variipennis (1), and Simulium meridionale (3). The C. sonorensis- and C. variipennis-positive pools were from nulliparous individuals, possibly indicating transovarial or venereal transmission as the source of virus. This is the first report of VSV-IN in field caught C. stellifer and the first report of either serotype in S. meridionale near outbreak premises. These results improve our understanding of the role midges and black flies play in VSV epidemiology in the United States and broadens the scope of vector species for targeted surveillance and control.
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Affiliation(s)
- Bethany L. McGregor
- Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA; (B.L.M.); (T.M.D.)
| | - Paula Rozo-Lopez
- Department of Entomology, Kansas State University, Manhattan, KS 66506, USA;
| | - Travis M. Davis
- Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA; (B.L.M.); (T.M.D.)
| | - Barbara S. Drolet
- Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA; (B.L.M.); (T.M.D.)
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9
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Morozov I, Davis AS, Ellsworth S, Trujillo JD, McDowell C, Shivanna V, Dasen EJ, Nichols R, Martin BK, Monath TP, Richt JA. Comparative evaluation of pathogenicity of three isolates of vesicular stomatitis virus (Indiana serotype) in pigs. J Gen Virol 2020; 100:1478-1490. [PMID: 31553299 DOI: 10.1099/jgv.0.001329] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Vesicular stomatitis (VS) is a notifiable disease of livestock affecting cattle, horses, pigs and humans. Vesicular stomatitis virus (VSV) serotypes Indiana and New Jersey are endemic to Central America; however, they also cause sporadic and scattered outbreaks in various countries in South and North America, including the USA. In order to develop an effective experimental challenge model for VSV, we compared the pathogenicity of three VSV serotype Indiana isolates in 36 4-5 week-old pigs. Two bovine isolates of Central American origin and one equine isolate from the USA were used for the experimental infections. Each pig was inoculated with a single isolate by both the intradermal and intranasal routes. Clinical signs of VSV infection were recorded daily for 10 days post-inoculation (days p.i.). Nasal and tonsillar swab samples and blood were collected to monitor immune responses, virus replication and shedding. Post-challenge, characteristic signs of VS were observed, including vesicles on the nasal planum and coronary bands, lameness, loss of hoof walls and pyrexia. Pigs inoculated with the Central American isolates showed consistently more severe clinical signs in comparison to the pigs infected with the USA isolate. Genomic RNA was isolated from the original challenge virus stocks, sequenced and compared to VSV genomes available in GenBank. Comparative genome analysis demonstrated significant differences between the VSV isolate from the USA and the two Central American isolates. Our results indicate that the Central American isolates of VSV serotype Indiana used in this study are more virulent in swine than the USA VSV serotype Indiana isolate and represent good candidate challenge strains for future VSV studies.
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Affiliation(s)
- Igor Morozov
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Kansas State University, Manhattan, KS, USA
| | - A Sally Davis
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, USA
| | - Steven Ellsworth
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Kansas State University, Manhattan, KS, USA
| | - Jessie D Trujillo
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Kansas State University, Manhattan, KS, USA
| | - Chester McDowell
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Kansas State University, Manhattan, KS, USA
| | - Vinay Shivanna
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Kansas State University, Manhattan, KS, USA
| | - Emily J Dasen
- BioProtection Systems Inc., NewLink Genetics Corp., Ames, IA, USA
| | - Richard Nichols
- BioProtection Systems Inc., NewLink Genetics Corp., Ames, IA, USA
| | - Brian K Martin
- BioProtection Systems Inc., NewLink Genetics Corp., Ames, IA, USA
| | - Thomas P Monath
- BioProtection Systems Inc., NewLink Genetics Corp., Ames, IA, USA
| | - Jurgen A Richt
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Kansas State University, Manhattan, KS, USA.,Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, USA
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10
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Lázaro Sales M, Dall'Agnol M, de Oliveira AM, Camargos MF, Fonseca AA, Dos Reis JKP. RT-qPCR for the diagnosis of the vesiculovirus Cocal virus. Arch Virol 2020; 165:1843-1847. [PMID: 32448993 DOI: 10.1007/s00705-020-04668-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 04/21/2020] [Indexed: 11/28/2022]
Abstract
Cocal virus (COCV) is one of the causative agents of vesicular stomatitis, presenting clinical signs indistinguishable from those caused by foot-and-mouth disease virus (FMDV). Therefore, the differentiation of these two viruses via laboratory diagnosis is essential. The objective of this study was to develop and validate a real-time quantitative PCR (RT-qPCR) protocol for the diagnosis of COCV directly from epithelial samples. The method developed had 97% accuracy at 3950 pfu and a repeatability error of 1.29%. RT-qPCR was able to distinguish COCV from other viruses that cause vesicular diseases, an important factor because seroneutralization may produce cross-reactivity between COCV and vesicular stomatitis Alagoas virus (VSAV). No epithelial sample originating from vesicular disease outbreaks between 2014 and 2018 in Brazil was positive for COCV.
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Affiliation(s)
- Mariana Lázaro Sales
- Departamento de Medicina Veterinária Preventiva da Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | | | | | | | - Jenner Karlisson Pimenta Dos Reis
- Departamento de Medicina Veterinária Preventiva da Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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11
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Venereal Transmission of Vesicular Stomatitis Virus by Culicoides sonorensis Midges. Pathogens 2020; 9:pathogens9040316. [PMID: 32344602 PMCID: PMC7238210 DOI: 10.3390/pathogens9040316] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/21/2020] [Accepted: 04/22/2020] [Indexed: 11/16/2022] Open
Abstract
Culicoides sonorensis biting midges are well-known agricultural pests and transmission vectors of arboviruses such as vesicular stomatitis virus (VSV). The epidemiology of VSV is complex and encompasses a broad range of vertebrate hosts, multiple routes of transmission, and diverse vector species. In temperate regions, viruses can overwinter in the absence of infected animals through unknown mechanisms, to reoccur the next year. Non-conventional routes for VSV vector transmission may help explain viral maintenance in midge populations during inter-epidemic periods and times of adverse conditions for bite transmission. In this study, we examined whether VSV could be transmitted venereally between male and female midges. Our results showed that VSV-infected females could venereally transmit virus to uninfected naïve males at a rate as high as 76.3% (RT-qPCR), 31.6% (virus isolation) during the third gonotrophic cycle. Additionally, VSV-infected males could venereally transmit virus to uninfected naïve females at a rate as high as 76.6% (RT-qPCR), 49.2% (virus isolation). Immunofluorescent staining of micro-dissected reproductive organs, immunochemical staining of midge histological sections, examination of internal reproductive organ morphology, and observations of mating behaviors were used to determine relevant anatomical sites for virus location and to hypothesize the potential mechanism for VSV transmission in C. sonorensis midges through copulation.
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de Oliveira AM, Fonseca AA, Camargos MF, Orzil LM, Laguardia-Nascimento M, Oliveira AGG, Rodrigues JG, Sales ML, de Oliveira TFP, de Melo CB. Development and validation of rt-qpcr for vesicular stomatitis virus detection (Alagoas vesiculovirus). J Virol Methods 2018; 257:7-11. [PMID: 29601843 DOI: 10.1016/j.jviromet.2018.03.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/20/2018] [Accepted: 03/26/2018] [Indexed: 11/29/2022]
Abstract
Vesicular stomatitis is an infectious disease that occurs mainly in countries of the Western Hemisphere and affects cattle, swine and horses. The clinical symptoms in cattle and swine are similar to foot-and-mouth disease and include vesicular ulceration of the tongue and mouth. The disease requires a rapid and accurate differential diagnosis, aiming for immediate implementation of control measures. The objective of the present study was to develop and perform validation tests of multiplex RT-qPCR(s) for the detection of RNA from Alagoas vesiculovirus, considering the parameters of sensitivity and analytical specificity, analytical performance (repeatability and reproducibility criteria) and the uncertainty of the measurement. The threshold cycle values obtained in triplicate from each sample were evaluated by considering the variations between days, analysts and equipment in an analysis of variance aimed at determining the variances of repeatability and reproducibility. The results showed that RT-qPCRs had excellent sensitivity and specificity in the detection of RNA of the Alagoas vesiculovirus. The validation parameters showed low coefficients of variation and were equivalent to those found in other validation studies, indicating that the tests presented excellent repeatability and reproducibility.
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Affiliation(s)
- Anapolino Macedo de Oliveira
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil; Universidade de Brasília - UnB/PPGCA, Campus Darcy Ribeiro, ICC Sul, Asa Norte, ZIP-Code: 70297-400, Brasília, DF, Brazil.
| | - Antônio Augusto Fonseca
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil.
| | - Marcelo Fernandes Camargos
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil.
| | - Lívia Maria Orzil
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil
| | - Mateus Laguardia-Nascimento
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil.
| | - Anna Gabriella Guimarães Oliveira
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil.
| | - Jacqueline Gomes Rodrigues
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil.
| | - Mariana Lázaro Sales
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil.
| | - Tatiana Flávia Pinheiro de Oliveira
- LANAGRO/MG - Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Avenida Rômulo Joviano, s/n, Postal Box 50, ZIP-Code: 33600-000, Pedro Leopoldo, MG, Brazil
| | - Cristiano Barros de Melo
- Universidade de Brasília - UnB/PPGCA, Campus Darcy Ribeiro, ICC Sul, Asa Norte, ZIP-Code: 70297-400, Brasília, DF, Brazil.
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Fowler VL, Howson ELA, Madi M, Mioulet V, Caiusi C, Pauszek SJ, Rodriguez LL, King DP. Development of a reverse transcription loop-mediated isothermal amplification assay for the detection of vesicular stomatitis New Jersey virus: Use of rapid molecular assays to differentiate between vesicular disease viruses. J Virol Methods 2016; 234:123-31. [PMID: 27118518 DOI: 10.1016/j.jviromet.2016.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 04/11/2016] [Accepted: 04/17/2016] [Indexed: 10/21/2022]
Abstract
Vesicular stomatitis (VS) is endemic in Central America and northern regions of South America, where sporadic outbreaks in cattle and pigs can cause clinical signs that are similar to foot-and-mouth disease (FMD). There is therefore a pressing need for rapid, sensitive and specific differential diagnostic assays that are suitable for decision making in the field. RT-LAMP assays have been developed for vesicular diseases such as FMD and swine vesicular disease (SVD) but there is currently no RT-LAMP assay that can detect VS virus (VSV), nor are there any multiplex RT-LAMP assays which permit rapid discrimination between these 'look-a-like' diseases in situ. This study describes the development of a novel RT-LAMP assay for the detection of VSV focusing on the New Jersey (VSNJ) serotype, which has caused most of the recent VS cases in the Americas. This RT-LAMP assay was combined in a multiplex format combining molecular lateral-flow devices for the discrimination between FMD and VS. This assay was able to detect representative VSNJV's and the limit of detection of the singleplex and multiplex VSNJV RT-LAMP assays were equivalent to laboratory based real-time RT-PCR assays. A similar multiplex RT-LAMP assay was developed to discriminate between FMDV and SVDV, showing that FMDV, SVDV and VSNJV could be reliably detected within epithelial suspensions without the need for prior RNA extraction, providing an approach that could be used as the basis for a rapid and low cost assay for differentiation of FMD from other vesicular diseases in the field.
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Affiliation(s)
- Veronica L Fowler
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom.
| | - Emma L A Howson
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom
| | - Mikidache Madi
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom
| | - Valérie Mioulet
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom
| | - Chiara Caiusi
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom
| | - Steven J Pauszek
- Plum Island Animal Disease Center, 40550 Main Rd, Orient, NY 11957, United States
| | - Luis L Rodriguez
- Plum Island Animal Disease Center, 40550 Main Rd, Orient, NY 11957, United States
| | - Donald P King
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, United Kingdom
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Nagy A, Černíková L, Vitásková E, Křivda V, Dán Á, Dirbáková Z, Jiřincová H, Procházka B, Sedlák K, Havlíčková M. MeltMan: Optimization, Evaluation, and Universal Application of a qPCR System Integrating the TaqMan qPCR and Melting Analysis into a Single Assay. PLoS One 2016; 11:e0151204. [PMID: 27031831 PMCID: PMC4816343 DOI: 10.1371/journal.pone.0151204] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/23/2016] [Indexed: 12/05/2022] Open
Abstract
In the present work, we optimised and evaluated a qPCR system integrating 6-FAM (6-carboxyfluorescein)-labelled TaqMan probes and melting analysis using the SYTO 82 (S82) DNA binding dye in a single reaction. We investigated the influence of the S82 on various TaqMan and melting analysis parameters and defined its optimal concentration. In the next step, the method was evaluated in 36 different TaqMan assays with a total of 729 paired reactions using various DNA and RNA templates, including field specimens. In addition, the melting profiles of interest were correlated with the electrophoretic patterns. We proved that the S82 is fully compatible with the FAM-TaqMan system. Further, the advantages of this approach in routine diagnostic TaqMan qPCR were illustrated with practical examples. These included solving problems with flat or other atypical amplification curves or even false negativity as a result of probe binding failure. Our data clearly show that the integration of the TaqMan qPCR and melting analysis into a single assay provides an additional control option as well as the opportunity to perform more complex analyses, get more data from the reactions, and obtain analysis results with higher confidence.
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Affiliation(s)
- Alexander Nagy
- Laboratory of Molecular Methods, State Veterinary Institute Prague, Prague, Czech Republic
- National Reference Laboratory for Influenza, National Institute of Public Health, Prague, Czech Republic
- * E-mail:
| | - Lenka Černíková
- Laboratory of Molecular Methods, State Veterinary Institute Prague, Prague, Czech Republic
| | - Eliška Vitásková
- Laboratory of Molecular Methods, State Veterinary Institute Prague, Prague, Czech Republic
| | - Vlastimil Křivda
- Laboratory of Molecular Methods, State Veterinary Institute Prague, Prague, Czech Republic
- Department of Virology and Serology, State Veterinary Institute Prague, Prague, Czech Republic
| | - Ádám Dán
- National Food Chain Safety Office, Veterinary Diagnostic Directorate, Molecular Biology Laboratory, Budapest, Hungary
| | - Zuzana Dirbáková
- Department of Virology, State Veterinary Institute Zvolen, Zvolen, Slovak Republic
| | - Helena Jiřincová
- National Reference Laboratory for Influenza, National Institute of Public Health, Prague, Czech Republic
| | - Bohumír Procházka
- Department of Informatics and Biostatistics, National Institute of Public Health, Prague, Czech Republic
| | - Kamil Sedlák
- Department of Virology and Serology, State Veterinary Institute Prague, Prague, Czech Republic
| | - Martina Havlíčková
- National Reference Laboratory for Influenza, National Institute of Public Health, Prague, Czech Republic
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Ramirez-Carvajal L, Long CR. Down-regulation of viral replication by lentiviral-mediated expression of short-hairpin RNAs against vesicular stomatitis virus ribonuclear complex genes. Antiviral Res 2012; 95:150-8. [DOI: 10.1016/j.antiviral.2012.05.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 05/03/2012] [Accepted: 05/17/2012] [Indexed: 10/28/2022]
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16
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Ferris NP, Clavijo A, Yang M, Velazquez-Salinas L, Nordengrahn A, Hutchings GH, Kristersson T, Merza M. Development and laboratory evaluation of two lateral flow devices for the detection of vesicular stomatitis virus in clinical samples. J Virol Methods 2011; 180:96-100. [PMID: 22230813 DOI: 10.1016/j.jviromet.2011.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 12/20/2011] [Indexed: 10/14/2022]
Abstract
Two lateral flow devices (LFD) for the detection of vesicular stomatitis (VS) virus (VSV), types Indiana (VSV-IND) and New Jersey (VSV-NJ) were developed using monoclonal antibodies C1 and F25VSVNJ-45 to the respective VSV serotypes. The performance of the LFDs was evaluated in the laboratory on suspensions of vesicular epithelia and cell culture passage derived supernatants of VSV. The collection of test samples included 105 positive for VSV-IND (92 vesicular epithelial suspensions and 13 cell culture antigens; encompassing 93 samples of subtype 1 [VSV-IND-1], 9 of subtype 2 [VSV-IND-2] and 3 of subtype 3 [VSV-IND-3]) and 189 positive for VSV-NJ (162 vesicular epithelial suspensions and 27 cell culture antigens) from suspected cases of vesicular disease in cattle and horses collected from 11 countries between 1937 and 2008 or else were derived from experimental infection and 777 samples that were either shown to be positive or negative for foot-and-mouth disease (FMD) virus (FMDV) and swine vesicular disease virus (SVDV) or else collected from healthy cattle or pigs and collected from 68 countries between 1965 and 2011. The diagnostic sensitivity of the VSV-IND (for reaction with VSV-IND-1) and VSV-NJ LFDs was either similar or identical at 94.6% (VSV-IND) and 97.4% (VSV-NJ) compared to 92.5% and 97.4% obtained by the reference method of antigen ELISA. The VSV-IND LFD failed to react with viruses of VSV-IND-2 and 3, while the VSV-NJ device recognized all VSV-NJ virus strains. The diagnostic specificities of the VSV-IND and VSV-NJ LFDs were 99.1% and 100, respectively, compared to 99.6% and 99.8% for the ELISA. Reactions with FMDV which can produce indistinguishable syndromes clinically in cattle, pigs and sheep and SVDV (vesicular disease in pigs) did not occur. These data illustrate the potential for the LFDs to be used next to the animal for providing rapid and objective support to veterinarians in their clinical judgment of vesicular disease and for the subtype (VSV-IND-1) and type-specific (VSV-NJ) pen-side diagnosis of VS and differential diagnosis from FMD.
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Affiliation(s)
- Nigel P Ferris
- Institute for Animal Health, Pirbright Laboratory, Pirbright, Woking, Surrey GU24 0NF, UK.
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Multiplex RT-PCR detection and microarray typing of vesicular disease viruses. J Virol Methods 2011; 175:236-45. [DOI: 10.1016/j.jviromet.2011.05.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 05/12/2011] [Accepted: 05/12/2011] [Indexed: 11/17/2022]
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18
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Clavijo A, Sun F, Lester T, Jasperson DC, Wilson WC. An improved real-time polymerase chain reaction for the simultaneous detection of all serotypes of Epizootic hemorrhagic disease virus. J Vet Diagn Invest 2010; 22:588-93. [PMID: 20622230 DOI: 10.1177/104063871002200414] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Epizootic hemorrhagic disease virus (EHDV) is a significant pathogen of wild and sometimes domestic ungulates worldwide. Rapid and reliable methods for virus detection and identification play an essential part in the control of epizootic hemorrhagic disease (EHD). In the present study, a 1-step real-time polymerase chain reaction (PCR) group-specific assay was developed. The assay detects genome segment 5 (NS1) from all of the 8 serotypes of EHDV. Assay sensitivity was evaluated relative to a conventional gel-based nested PCR using cell culture-derived virus and diagnostic samples from clinically affected white-tailed deer (Odocoileus virginianus). The assay reliably amplified the NS1 gene from any of the EHDV strains tested, including isolates from each of the 8 EHDV serotypes. No cross-reactions were detected when all 24 serotypes of Bluetongue virus, a closely related member of the genus Orbivirus, were tested. A panel of 76 known EHDV-positive clinical samples was used to compare the performance of the assay relative to a previously reported real-time PCR assay. Results indicated that there was no statistically significant difference between the threshold cycle values obtained with both assays. A collection of 178 diagnostic samples submitted for EHD diagnosis was also used for test evaluation. The assay could be applied for rapid detection of EHDV in clinical samples from susceptible ruminants during an outbreak of the disease. In addition, this PCR assay has the benefits of being reliable and simple and could provide a valuable tool for studying the epidemiology of EHDV infection in susceptible ruminants by facilitating the detection of EHDV, regardless of the serotype.
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Affiliation(s)
- Alfonso Clavijo
- Texas Veterinary Medical Diagnostic Laboratory, 1 Sippel Road, College Station, TX 77845, USA.
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