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Braddick M, O’Brien HM, Lim CK, Feldman R, Bunter C, Neville P, Bailie CR, Butel-Simoes G, Jung MH, Yuen A, Hughes N, Friedman ND. An integrated public health response to an outbreak of Murray Valley encephalitis virus infection during the 2022-2023 mosquito season in Victoria. Front Public Health 2023; 11:1256149. [PMID: 37860808 PMCID: PMC10582942 DOI: 10.3389/fpubh.2023.1256149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/18/2023] [Indexed: 10/21/2023] Open
Abstract
Introduction Murray Valley encephalitis virus (MVEV) is a mosquito-borne flavivirus known to cause infrequent yet substantial human outbreaks around the Murray Valley region of south-eastern Australia, resulting in significant mortality. Methods The public health response to MVEV in Victoria in 2022-2023 included a climate informed pre-season risk assessment, and vector surveillance with mosquito trapping and laboratory testing for MVEV. Human cases were investigated to collect enhanced surveillance data, and human clinical samples were subject to serological and molecular testing algorithms to assess for co-circulating flaviviruses. Equine surveillance was carried out via enhanced investigation of cases of encephalitic illness. Integrated mosquito management and active health promotion were implemented throughout the season and in response to surveillance signals. Findings Mosquito surveillance included a total of 3,186 individual trapping events between 1 July 2022 and 20 June 2023. MVEV was detected in mosquitoes on 48 occasions. From 2 January 2023 to 23 April 2023, 580 samples (sera and CSF) were tested for flaviviruses. Human surveillance detected 6 confirmed cases of MVEV infection and 2 cases of "flavivirus-unspecified." From 1 September 2022 to 30 May 2023, 88 horses with clinical signs consistent with flavivirus infection were tested, finding one probable and no confirmed cases of MVE. Discussion The expanded, climate-informed vector surveillance system in Victoria detected MVEV in mosquitoes in advance of human cases, acting as an effective early warning system. This informed a one-health oriented public health response including enhanced human, vector and animal surveillance, integrated mosquito management, and health promotion.
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Affiliation(s)
- Maxwell Braddick
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
- Victorian Infectious Diseases Service, The Royal Melbourne Hospital, The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Helen M. O’Brien
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - Chuan K. Lim
- Victorian Infectious Diseases Reference Laboratory, The Royal Melbourne Hospital, The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Department of Infectious Diseases, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
| | - Rebecca Feldman
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - Cathy Bunter
- Agriculture Victoria, Department of Energy, Environment and Climate Action, Melbourne, VIC, Australia
| | - Peter Neville
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - Christopher R. Bailie
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - Grace Butel-Simoes
- Victorian Infectious Diseases Reference Laboratory, The Royal Melbourne Hospital, The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Min-Ho Jung
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - Aidan Yuen
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - Nicole Hughes
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
| | - N. Deborah Friedman
- Communicable Diseases Section, Health Protection Branch, Victorian Department of Health, Melbourne, VIC, Australia
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Review of -omics studies on mosquito-borne viruses of the Flavivirus genus. Virus Res 2022; 307:198610. [PMID: 34718046 DOI: 10.1016/j.virusres.2021.198610] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/18/2021] [Accepted: 10/11/2021] [Indexed: 02/06/2023]
Abstract
Arboviruses are transmitted by arthropods (arthropod-borne virus) which can be mosquitoes or other hematophagous arthropods, in which their life cycle occurs before transmission to other hosts. Arboviruses such as Dengue, Zika, Saint Louis Encephalitis, West Nile, Yellow Fever, Japanese Encephalitis, Rocio and Murray Valley Encephalitis viruses are some of the arboviruses transmitted biologically among vertebrate hosts by blood-taking vectors, mainly Aedes and Culex sp., and are associated with neurological, viscerotropic, and hemorrhagic reemerging diseases, posing as significant health and socioeconomic concern, as they become more and more adaptive to new environments, to arthropods vectors and human hosts. One of the main families that include mosquito-borne viruses is Flaviviridae, and here, we review the case of the Flavivirus genus, which comprises the viruses cited above, using a variety of research approaches published in literature, including genomics, transcriptomics, proteomics, metabolomics, etc., to better understand their structures as well as virus-host interactions, which are essential for development of future antiviral therapies.
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Vasilakis N, Tesh RB, Popov VL, Widen SG, Wood TG, Forrester NL, Gonzalez JP, Saluzzo JF, Alkhovsky S, Lam SK, Mackenzie JS, Walker PJ. Exploiting the Legacy of the Arbovirus Hunters. Viruses 2019; 11:E471. [PMID: 31126128 PMCID: PMC6563318 DOI: 10.3390/v11050471] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/15/2019] [Accepted: 05/21/2019] [Indexed: 12/13/2022] Open
Abstract
In recent years, it has become evident that a generational gap has developed in the community of arbovirus research. This apparent gap is due to the dis-investment of training for the next generation of arbovirologists, which threatens to derail the rich history of virus discovery, field epidemiology, and understanding of the richness of diversity that surrounds us. On the other hand, new technologies have resulted in an explosion of virus discovery that is constantly redefining the virosphere and the evolutionary relationships between viruses. This paradox presents new challenges that may have immediate and disastrous consequences for public health when yet to be discovered arboviruses emerge. In this review we endeavor to bridge this gap by providing a historical context for the work being conducted today and provide continuity between the generations. To this end, we will provide a narrative of the thrill of scientific discovery and excitement and the challenges lying ahead.
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Affiliation(s)
- Nikos Vasilakis
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Institute for Human Infection and Immunity, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Tropical Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
| | - Robert B Tesh
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Institute for Human Infection and Immunity, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Tropical Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
| | - Vsevolod L Popov
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Institute for Human Infection and Immunity, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Tropical Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
| | - Steve G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston TX 77555, USA.
| | - Thomas G Wood
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston TX 77555, USA.
| | - Naomi L Forrester
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Institute for Human Infection and Immunity, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
- Center for Tropical Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
| | - Jean Paul Gonzalez
- Center of Excellence for Emerging & Zoonotic Animal Disease, Kansas State University, Manhattan, KS 66502, USA.
| | | | - Sergey Alkhovsky
- Ivanovsky Institute of Virology, N.F. Gamaleya National Research Center for Epidemiology and Microbiology, Ministry of Healthcare of the Russian Federation, 123098, 18 Gamaleya str., Moscow, Russia.
| | - Sai Kit Lam
- Department of Medical Microbiology, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - John S Mackenzie
- Faculty of Medical Sciences, Curtin University, Perth, Western Australia 6102, Australia.
| | - Peter J Walker
- School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia.
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Mackenzie JS, Lindsay MDA, Smith DW, Imrie A. The ecology and epidemiology of Ross River and Murray Valley encephalitis viruses in Western Australia: examples of One Health in Action. Trans R Soc Trop Med Hyg 2018; 111:248-254. [PMID: 29044370 PMCID: PMC5914307 DOI: 10.1093/trstmh/trx045] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 07/27/2017] [Indexed: 01/02/2023] Open
Abstract
Arboviruses are maintained and transmitted through an alternating biological cycle in arthropods and vertebrates, with largely incidental disease in humans and animals. As such, they provide excellent examples of One Health, as their health impact is inextricably linked to their vertebrate hosts, their arthropod vectors and the environment. Prevention and control requires a comprehensive understanding of these interactions, and how they may be effectively and safely modified. This review concentrates on human disease due to Ross River and Murray Valley encephalitis viruses, the two major arboviral pathogens in Australia. It describes how their pattern of infection and disease is influenced by natural climatic and weather patterns, and by anthropogenic activities. The latter includes human-mediated environmental manipulations, such as water impoundment infrastructures, human movements and migration, and community and social changes, such as urban spread into mosquito larval habitats. Effective interventions need to be directed at the environmental precursors of risk. This can best be achieved using One Health approaches to improve collaboration and coordination between different disciplines and cross-sectoral jurisdictions in order to develop more holistic mitigation and control procedures, and to address poorly understood ecological issues through multidisciplinary research.
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Affiliation(s)
- John S Mackenzie
- Department of Microbiology, PathWest Laboratory Medicine WA, QEII Medical Centre, Nedlands, WA 6009
- Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845
- Corresponding author: Present address: 5E, 16 Kings Park Avenue, Crawley, WA 6009; Tel: +61 439 875 697; E-mail:
| | - Michael D A Lindsay
- Public and Aboriginal Health Division, Department of Health, Grace Vaughan House, Shenton Park, Western Australia, WA 6008
| | - David W Smith
- Department of Microbiology, PathWest Laboratory Medicine WA, QEII Medical Centre, Nedlands, WA 6009
- Faculty of Medicine and Health Sciences, University of Western Australia, Nedlands, WA 6009, Australia
| | - Allison Imrie
- Department of Microbiology, PathWest Laboratory Medicine WA, QEII Medical Centre, Nedlands, WA 6009
- Faculty of Medicine and Health Sciences, University of Western Australia, Nedlands, WA 6009, Australia
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Cella E, Gabrielli I, Zehender G, Giovanetti M, Presti AL, Lai A, Dicuonzo G, Angeletti S, Salemi M, Ciccozzi M. Phylogeny of Murray Valley encephalitis virus in Australia and Papua New Guinea. ASIAN PAC J TROP MED 2016; 9:385-389. [PMID: 27086158 DOI: 10.1016/j.apjtm.2016.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 02/20/2016] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE To study the genetic diversity of Murray Valley encephalitis virus (MVEV) in Australia and Papua New Guinea. METHODS MVEV envelope gene sequences were aligned using Clustal X and manual editing was performed with Bioedit. ModelTest v. 3.7 was used to select the simplest evolutionary model that adequately fitted the sequence data. Maximum likelihood analysis was performed using PhyML. The phylogenetic signal of the dataset was investigated by the likelihood mapping analysis. The Bayesian phylogenetic tree was built using BEAST. RESULTS The phylogenetic trees showed two main clades. The clade Ⅰ including eight strains isolated from West Australia. The clade Ⅱ was characterized by at least four epidemic entries, three of which localized in Northern West Australia and one in Papua New Guinea. The estimated mean evolutionary rate value of the MVEV envelope gene was 0.407 × 10(-3) substitution/site/year (95% HPD: 0.623 × 10(-4)-0.780 × 10(-3)). Population dynamics defines a relative constant population until the year 2000, when a reduction occurred, probably due to a bottleneck. CONCLUSIONS This study has been useful in supporting the probable connection between climate changes and viral evolution also by the vector point of view; multidisciplinary monitoring studies are important to prevent new viral epidemics inside and outside new endemic areas.
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Affiliation(s)
- Eleonora Cella
- Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy; Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | | | | | - Marta Giovanetti
- Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy; University of Rome 'Tor Vergata', Italy
| | - Alessandra Lo Presti
- Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy
| | - Alessia Lai
- L. Sacco Department of Biomedical and Clinical Sciences, University of Milan, Italy
| | - Giordano Dicuonzo
- Clinical Pathology and Microbiology Laboratory, University Hospital Campus Bio-Medico of Rome, Italy
| | - Silvia Angeletti
- Clinical Pathology and Microbiology Laboratory, University Hospital Campus Bio-Medico of Rome, Italy
| | - Marco Salemi
- Department of Pathology and Laboratory Medicine, University of Florida, Gainesville, FL, USA
| | - Massimo Ciccozzi
- Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy; University Hospital Campus Bio-Medico, Rome, Italy.
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Williams DT, Diviney SM, Niazi AUR, Durr PA, Chua BH, Herring B, Pyke A, Doggett SL, Johansen CA, Mackenzie JS. The Molecular Epidemiology and Evolution of Murray Valley Encephalitis Virus: Recent Emergence of Distinct Sub-lineages of the Dominant Genotype 1. PLoS Negl Trop Dis 2015; 9:e0004240. [PMID: 26600318 PMCID: PMC4657991 DOI: 10.1371/journal.pntd.0004240] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 10/26/2015] [Indexed: 12/14/2022] Open
Abstract
Background Recent increased activity of the mosquito-borne Murray Valley encephalitis virus (MVEV) in Australia has renewed concerns regarding its potential to spread and cause disease. Methodology/Principal Findings To better understand the genetic relationships between earlier and more recent circulating strains, patterns of virus movement, as well as the molecular basis of MVEV evolution, complete pre-membrane (prM) and Envelope (Env) genes were sequenced from sixty-six MVEV strains from different regions of the Australasian region, isolated over a sixty year period (1951–2011). Phylogenetic analyses indicated that, of the four recognized genotypes, only G1 and G2 are contemporary. G1 viruses were dominant over the sampling period and found across the known geographic range of MVEV. Two distinct sub-lineages of G1 were observed (1A and 1B). Although G1B strains have been isolated from across mainland Australia, Australian G1A strains have not been detected outside northwest Australia. Similarly, G2 is comprised of only Western Australian isolates from mosquitoes, suggesting G1B and G2 viruses have geographic or ecological restrictions. No evidence of recombination was found and a single amino acid substitution in the Env protein (S332G) was found to be under positive selection, while several others were found to be under directional evolution. Evolutionary analyses indicated that extant genotypes of MVEV began to diverge from a common ancestor approximately 200 years ago. G2 was the first genotype to diverge, followed by G3 and G4, and finally G1, from which subtypes G1A and G1B diverged between 1964 and 1994. Conclusions/Significance The results of this study provides new insights into the genetic diversity and evolution of MVEV. The demonstration of co-circulation of all contemporary genetic lineages of MVEV in northwestern Australia, supports the contention that this region is the enzootic focus for this virus. Murray Valley encephalitis virus is the most significant cause of mosquito-borne encephalitis in humans in Australia, and can also cause neurological disease in horses. This study reports an expanded phylogenetic study of this virus and the first molecular evolutionary analysis. Of the four recognized genotypes of Murray Valley encephalitis virus, only two were found to be actively circulating (genotypes 1 and 2), and genotype 1 was dominant. Distinct genetic sub-lineages within genotype 1 were found to have recently emerged. Molecular clock analysis indicated that genotype 2 viruses are the oldest genetic lineage while genotype 1 viruses are the most recent to diverge. The co-circulation of distinct genetic lineages of this virus in northwestern Australia, comprising the oldest and youngest lineages, supports previous findings that MVEV circulates endemically in this region.
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Affiliation(s)
- David T. Williams
- CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia
- * E-mail: (DW); (SMD)
| | - Sinéad M. Diviney
- Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia
- * E-mail: (DW); (SMD)
| | - Aziz-ur-Rahman Niazi
- Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia
| | - Peter A. Durr
- CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia
| | - Beng Hooi Chua
- Office of Research and Development, Curtin University, Perth, Western Australia, Australia
| | - Belinda Herring
- Infectious Diseases and Immunology, University of Sydney, New South Wales, Australia
| | - Alyssa Pyke
- Public Health Virology, Queensland Health Forensic and Scientific Services, Coopers Plains, Queensland, Australia
| | - Stephen L. Doggett
- Department of Medical Entomology, Westmead Hospital, University of Sydney and Institute for Clinical Pathology and Medical Research, New South Wales, Australia
| | - Cheryl A. Johansen
- Arbovirus Surveillance and Research Laboratory, School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - John S. Mackenzie
- Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia
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Ang MJY, Li Z, Lim HA, Ng FM, Then SW, Wee JLK, Joy J, Hill J, Chia CSB. A P2 and P3 substrate specificity comparison between the Murray Valley encephalitis and West Nile virus NS2B/NS3 protease using C-terminal agmatine dipeptides. Peptides 2014; 52:49-52. [PMID: 24333681 DOI: 10.1016/j.peptides.2013.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 12/02/2013] [Accepted: 12/02/2013] [Indexed: 12/26/2022]
Abstract
The Murray Valley encephalitis virus (MVEV) and the West Nile virus (WNV) are mosquito-borne single-stranded RNA Flaviviruses responsible for many cases of viral encephalitis and deaths worldwide. The former is endemic in north Australia and Papua New Guinea while the latter has spread to different parts of the world and was responsible for a recent North American outbreak in 2012, resulting in 243 fatalities. There is currently no approved vaccines or drugs against MVEV and WNV viral infections. A plausible drug target is the viral non-structural NS2B/NS3 protease due to its role in viral replication. This trypsin-like serine protease recognizes and cleaves viral polyproteins at the C-terminal end of an arginine residue, opening an avenue for the development of peptide-based antivirals. This communication compares the P2 and P3 residue preferences of the MVEV and WNV NS2B/NS3 proteases using a series of C-terminal agmatine dipeptides. Our results revealed that both viral enzymes were highly specific toward lysines at the P2 and P3 positions, suggesting that a peptidomimetic viral protease inhibitor developed against one virus should also be active against the other.
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Affiliation(s)
- Melgious Jin Yan Ang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Zhitao Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Huichang Annie Lim
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Fui Mee Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Siew Wen Then
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - John Liang Kuan Wee
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Joma Joy
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - Jeffrey Hill
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore
| | - C S Brian Chia
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos #03-01, Singapore 138669, Singapore.
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Booss J, Tselis AC. A history of viral infections of the central nervous system: foundations, milestones, and patterns. HANDBOOK OF CLINICAL NEUROLOGY 2014; 123:3-44. [PMID: 25015479 DOI: 10.1016/b978-0-444-53488-0.00001-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- John Booss
- Departments of Neurology and Laboratory Medicine, Yale University School of Medicine, New Haven, CT and Department of Veterans Affairs Medical Center, VA Connecticut, West Haven, CT, USA
| | - Alex C Tselis
- Department of Neurology, School of Medicine, Wayne State University, Detroit, MI, USA.
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Abstract
Bovine ephemeral fever virus (BEFV) is an arthropod-borne rhabdovirus that causes a debilitating disease of cattle in Africa, Asia, and Australia; however, its global geodynamics are poorly understood. An evolutionary analysis of G gene (envelope glycoprotein) ectodomain sequences of 97 BEFV isolates collected from Australia during 1956 to 2012 revealed that all have a single common ancestor and are phylogenetically distinct from BEFV sampled in other geographical regions. The age of the Australian clade is estimated to be between 56 and 65 years, suggesting that BEFV has entered the continent on few occasions since it was first reported in 1936 and that the 1955-1956 epizootic was the source of all currently circulating viruses. Notably, the Australian clade has evolved as a single genetic lineage across the continent and at a high evolutionary rate of ∼10(-3) nucleotide substitutions/site/year. Screening of 66 isolates using monoclonal antibodies indicated that neutralizing antigenic sites G1, G2, and G4 have been relatively stable, although variations in site G3a/b defined four antigenic subtypes. A shift in an epitope at site G3a, which occurred in the mid-1970s, was strongly associated with a K218R substitution. Similarly, a shift at site G3b was associated primarily with substitutions at residues 215, 220, and 223, which map to the tip of the spike on the prefusion form of the G protein. Finally, we propose that positive selection on residue 215 was due to cross-reacting neutralizing antibody to Kimberley virus (KIMV). This is the first study of the evolution of BEFV in Australia, showing that the virus has entered the continent only once during the past 50 to 60 years, it is evolving at a relatively constant rate as a single genetic lineage, and although the virus is relatively stable antigenically, mutations have resulted in four antigenic subtypes. Furthermore, the study shows that the evolution of BEFV in Australia appears to be driven, at least in part, by cross-reactive antibodies to KIMV which has a similar distribution and ecology but has not been associated with disease. As BEFV and KIMV are each known to be present in Africa and Asia, this interaction may occur on a broader geographic scale.
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Substrate-based peptidomimetic inhibitors of the Murray Valley encephalitis virus NS2B/NS3 serine protease: A P1–P4 SAR study. Eur J Med Chem 2013; 68:72-80. [DOI: 10.1016/j.ejmech.2013.07.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 07/03/2013] [Accepted: 07/13/2013] [Indexed: 12/30/2022]
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Knox J, Cowan RU, Doyle JS, Ligtermoet MK, Archer JS, Burrow JNC, Tong SYC, Currie BJ, Mackenzie JS, Smith DW, Catton M, Moran RJ, Aboltins CA, Richards JS. Murray Valley encephalitis: a review of clinical features, diagnosis and treatment. Med J Aust 2012; 196:322-6. [PMID: 22432670 DOI: 10.5694/mja11.11026] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 11/30/2011] [Indexed: 01/12/2023]
Abstract
Murray Valley encephalitis virus (MVEV) is a mosquito-borne virus that is found across Australia, Papua New Guinea and Irian Jaya. MVEV is endemic to northern Australia and causes occasional outbreaks across south-eastern Australia. 2011 saw a dramatic increase in MVEV activity in endemic regions and the re-emergence of MVEV in south-eastern Australia. This followed significant regional flooding and increased numbers of the main mosquito vector, Culex annulirostris, and was evident from the widespread seroconversion of sentinel chickens, fatalities among horses and several cases in humans, resulting in at least three deaths. The last major outbreak in Australia was in 1974, during which 58 cases were identified and the mortality rate was about 20%. With the potential for a further outbreak of MVEV in the 2011-2012 summer and following autumn, we highlight the importance of this disease, its clinical characteristics and radiological and laboratory features. We present a suspected but unproven case of MVEV infection to illustrate some of the challenges in clinical management. It remains difficult to establish an early diagnosis of MVEV infection, and there is a lack of proven therapeutic options.
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Affiliation(s)
- James Knox
- Victorian Infectious Diseases Service, Royal Melbourne Hospital, Melbourne, Australia
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The contribution of rodent models to the pathological assessment of flaviviral infections of the central nervous system. Arch Virol 2012; 157:1423-40. [PMID: 22592957 DOI: 10.1007/s00705-012-1337-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 03/30/2012] [Indexed: 12/16/2022]
Abstract
Members of the genus Flavivirus are responsible for a spectrum of important neurological syndromes in humans and animals. Rodent models have been used extensively to model flavivirus neurological disease, to discover host-pathogen interactions that influence disease outcome, and as surrogates to determine the efficacy and safety of vaccines and therapeutics. In this review, we discuss the current understanding of flavivirus neuroinvasive disease and outline the host, viral and experimental factors that influence the outcome and reliability of virus infection of small-animal models.
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Appuhamy RD, Tent J, Mackenzie JS. Toponymous diseases of Australia. Med J Aust 2011; 193:642-6. [PMID: 21143049 DOI: 10.5694/j.1326-5377.2010.tb04092.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 09/01/2010] [Indexed: 11/17/2022]
Abstract
Names are more than just labels used to identify diseases. They can be windows into the discovery, characteristics and attributes of the disease. Toponymous diseases are diseases that are named after places. Hendra, Ross River, Bairnsdale, Murray Valley and Barmah Forest are all examples of Australian places that have had diseases named after them. They all have unique and interesting stories that provide a glimpse into their discovery, history and culture. Because of perceived negative connotations, the association of diseases with placenames has sometimes generated controversy.
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Affiliation(s)
- Ranil D Appuhamy
- Health Protection Directorate, Queensland Health, Brisbane, QLD, Australia.
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14
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Joy J, Mee NF, Kuan WL, Perlyn KZ, Wen TS, Hill J. Biochemical characterisation of Murray Valley encephalitis virus proteinase. FEBS Lett 2010; 584:3149-52. [PMID: 20621842 DOI: 10.1016/j.febslet.2010.05.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 05/21/2010] [Accepted: 05/27/2010] [Indexed: 11/28/2022]
Abstract
Murray Valley encephalitis virus (MVEV) is a member of the flavivirus group, a large family of single stranded RNA viruses, which cause serious disease in all regions of the world. Its genome encodes a large polyprotein which is processed by both host proteinases and a virally encoded serine proteinase, non-structural protein 3 (NS3). NS3, an essential viral enzyme, requires another virally encoded protein cofactor, NS2B, for proteolytic activity. The cloning, expression and biochemical characterisation of a stable MVEV NS2B-NS3 fusion protein is described.
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Affiliation(s)
- Joma Joy
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*Star), Singapore, Singapore
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15
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Weissenböck H, Hubálek Z, Bakonyi T, Nowotny N. Zoonotic mosquito-borne flaviviruses: worldwide presence of agents with proven pathogenicity and potential candidates of future emerging diseases. Vet Microbiol 2009; 140:271-80. [PMID: 19762169 DOI: 10.1016/j.vetmic.2009.08.025] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 07/03/2009] [Accepted: 08/21/2009] [Indexed: 11/29/2022]
Abstract
An update on the mosquito-borne flavivirus species including certain subtypes, as listed in the Eighth Report of the International Committee on Taxonomy of Viruses, is given. Special emphasis is placed on viruses which have been shown to cause diseases in animals, and viruses for which no pathogenicity has been proven yet. Several recent examples (Usutu virus and lineage-2 West Nile virus in central Europe, Zika virus in Micronesia) have shown that sources providing information on such scientifically largely neglected viruses are valuable tools for scientists and public health officials having to deal with such disease emergences. Furthermore the effects of global warming will lead to introduction of competent mosquito vectors into temperate climate zones and will increase efficiency of viral replication in less competent vector species. This, facilitated by rising global travel and trade activities, will facilitate introduction and permanent establishment of mosquito-borne viruses, some of which may become of public health or veterinary concern, into novel environments, e.g. industrialized countries worldwide.
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Affiliation(s)
- H Weissenböck
- Institute of Pathology and Forensic Veterinary Medicine, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria.
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16
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Schweitzer BK, Chapman NM, Iwen PC. Overview of theFlaviviridaeWith an Emphasis on the Japanese Encephalitis Group Viruses. Lab Med 2009. [DOI: 10.1309/lm5yws85njpcwesw] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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17
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Leyssen P, Croes R, Rau P, Heiland S, Verbeken E, Sciot R, Paeshuyse J, Charlier N, De Clercq E, Meyding‐Lamadé U, Neyts J. Acute encephalitis, a poliomyelitis-like syndrome and neurological sequelae in a hamster model for flavivirus infections. Brain Pathol 2006; 13:279-90. [PMID: 12946018 PMCID: PMC8095928 DOI: 10.1111/j.1750-3639.2003.tb00028.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Infection of hamsters with the murine flavivirus Modoc results in (meningo)encephalitis, which is, during the acute phase, frequently associated with flaccid paralysis, as also observed in patients with West Nile virus encephalitis. Twenty percent of the hamsters that recover from the acute encephalitis develop life-long neurological sequelae, reminiscent of those observed, for example, in survivors of Japanese encephalitis. Magnetic resonance imaging and histology revealed severe lesions predominantly located in the olfactory-limbic system, both in hamsters with acute encephalitis as in survivors. Prominent pathology was also detected in the spinal cord of hamsters with paralysis. Modoc virus infections in hamsters provide a unique model for the study of encephalitis, a poliomyelitis-like syndrome and neurological sequelae following flavivirus infection.
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Affiliation(s)
- Pieter Leyssen
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
| | - Romaric Croes
- Department of Morphology and Molecular Pathology, Katholieke Universiteit Leuven, Belgium
| | - Philipp Rau
- Department of Neurology, University of Heidelberg, Germany
| | - Sabine Heiland
- Department of Neurology, University of Heidelberg, Germany
| | - Erik Verbeken
- Department of Morphology and Molecular Pathology, Katholieke Universiteit Leuven, Belgium
| | - Raphael Sciot
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
| | - Jan Paeshuyse
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
| | - Nathalie Charlier
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
| | - Erik De Clercq
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
| | | | - Johan Neyts
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
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18
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Abstract
West Nile virus (WNV) has spread across the United States causing annual outbreaks since its emergence in 1999. Although severe disease develops only in about 1% of infections, WNV has claimed a total of 564 lives in the 5 years from 1999 to 2003. Observation of flaccid paralysis due to WNV infection at a higher incidence than previously documented and the devastating mortality recorded in infected American bird species triggered concerns about a potentially enhanced virulence of this virus. Here we summarize recent observations made during the American outbreaks regarding host range and transmission modes of WNV, and discuss epidemiological aspects of the emergence of this pathogen in the new habitat.
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Affiliation(s)
- Thomas Briese
- The Jerome L. and Dawn Greene Infectious Disease Laboratory, Mailman School of Public Health, Columbia University, New York 10032, USA
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19
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Leyssen P, Drosten C, Paning M, Charlier N, Paeshuyse J, De Clercq E, Neyts J. Interferons, interferon inducers, and interferon-ribavirin in treatment of flavivirus-induced encephalitis in mice. Antimicrob Agents Chemother 2003; 47:777-82. [PMID: 12543691 PMCID: PMC151739 DOI: 10.1128/aac.47.2.777-782.2003] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We evaluated the prophylactic and therapeutic efficacy of interferon alpha-2b, pegylated interferon alpha-2b, poly(I. C), and Ampligen against Modoc virus encephalitis in an animal model for flavivirus infections. All compounds significantly delayed virus-induced morbidity (paralysis) and mortality (due to progressive encephalitis). Viral load (as measured on day 7 postinfection) was significantly reduced by 80 to 100% in the serum, brain, and spleen in mice that had been treated with either interferon alpha-2b, pegylated interferon alpha-2b, poly(I. C), or Ampligen. We also studied whether a combination of interferon alpha-2b and ribavirin (presently the standard therapy for the treatment of infections with hepatitis C virus) would be more effective than treatment with interferon alone. However, ribavirin did not enhance the inhibitory effect of interferon therapy in this animal model for flavivirus infections.
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Affiliation(s)
- Pieter Leyssen
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium
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20
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Hurrelbrink RJ, McMinn PC. Attenuation of Murray Valley encephalitis virus by site-directed mutagenesis of the hinge and putative receptor-binding regions of the envelope protein. J Virol 2001; 75:7692-702. [PMID: 11462041 PMCID: PMC115004 DOI: 10.1128/jvi.75.16.7692-7702.2001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2001] [Accepted: 05/16/2001] [Indexed: 11/20/2022] Open
Abstract
Molecular determinants of virulence in flaviviruses cluster in two regions on the three-dimensional structure of the envelope (E) protein; the base of domain II, believed to serve as a hinge during pH-dependent conformational change in the endosome, and the lateral face of domain III, which contains an integrin-binding motif Arg-Gly-Asp (RGD) in mosquito-borne flaviviruses and is believed to form the receptor-binding site of the protein. In an effort to better understand the nature of attenuation caused by mutations in these two regions, a full-length infectious cDNA clone of Murray Valley encephalitis virus prototype strain 1-51 (MVE-1-51) was employed to produce a panel of site-directed mutants with substitutions at amino acid positions 277 (E-277; hinge region) or 390 (E-390; RGD motif). Viruses with mutations at E-277 (Ser-->Ile, Ser-->Asn, Ser-->Val, and Ser-->Pro) showed various levels of in vitro and in vivo attenuation dependent on the level of hydrophobicity of the substituted amino acid. Altered hemagglutination activity observed for these viruses suggests that mutations in the hinge region may indirectly disrupt the receptor-ligand interaction, possibly by causing premature release of the virion from the endosomal membrane prior to fusion. Similarly, viruses with mutations at E-390 (Asp-->Asn, Asp-->Glu, and Asp-->Tyr) were also attenuated in vitro and in vivo; however, the absorption and penetration rates of these viruses were similar to those of wild-type virus. This, coupled with the fact that E-390 mutant viruses were only moderately inhibited by soluble heparin, suggests that RGD-dependent integrin binding is not essential for entry of MVE and that multiple and/or alternate receptors may be involved in cell entry.
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Affiliation(s)
- R J Hurrelbrink
- Department of Microbiology, University of Western Australia, Nedlands, Western Australia 6907, Australia.
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21
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Leyssen P, Drosten C, Schmitz H, Neyts J. A novel model for the study of the therapy of flavivirus infections using the Modoc virus. Virology 2001; 279:27-37. [PMID: 11145886 DOI: 10.1006/viro.2000.0723] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The murine Flavivirus Modoc replicates well in Vero cells and appears to be as equally sensitive as both yellow fever and dengue fever virus to a selection of antiviral agents. Infection of SCID mice, by either the intracerebral, intraperitoneal, or intranasal route, results in 100% mortality. Immunocompetent mice and hamsters proved to be susceptible to the virus only when inoculated via the intranasal or intracerebral route. Animals ultimately die of (histologically proven) encephalitis with features similar to Flavivirus encephalitis in man. Viral RNA was detected in the brain, spleen, and salivary glands of infected SCID mice and the brain, lung, kidney, and salivary glands of infected hamsters. In SCID mice, the interferon inducer poly IC protected against Modoc virus-induced morbidity and mortality and this protection was associated with a reduction in infectious virus content and viral RNA load. Infected hamsters shed the virus in the urine. This allows daily monitoring of (inhibition of) viral replication, by means of a noninvasive method and in the same animal. The Modoc virus model appears attractive for the study of chemoprophylactic or chemotherapeutic strategies against Flavivirus infections.
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Affiliation(s)
- P Leyssen
- Rega Institute for Medical Research, Leuven, B-3000, Belgium
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22
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Abstract
The family Flaviviridae contains three genera: Hepacivirus, Flavivirus, and Pestivirus. Worldwide, more than 170 million people are chronically infected with Hepatitis C virus and are at risk of developing cirrhosis and/or liver cancer. In addition, infections with arthropod-borne flaviviruses (such as dengue fever, Japanese encephalitis, tick-borne encephalitis, St. Louis encephalitis, Murray Valley encephalitis, West Nile, and yellow fever viruses) are emerging throughout the world. The pestiviruses have a serious impact on livestock. Unfortunately, no specific antiviral therapy is available for the treatment or the prevention of infections with members of the Flaviviridae. Ongoing research has identified possible targets for inhibition, including binding of the virus to the cell, uptake of the virus into the cell, the internal ribosome entry site of hepaciviruses and pestiviruses, the capping mechanism of flaviviruses, the viral proteases, the viral RNA-dependent RNA polymerase, and the viral helicase. In light of recent developments, the prevalence of infections caused by these viruses, the disease spectrum, and the impact of infections, different strategies that could be pursued to specifically inhibit viral targets and animal models that are available to study the pathogenesis and antiviral strategies are reviewed.
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23
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Leyssen P, De Clercq E, Neyts J. Perspectives for the treatment of infections with Flaviviridae. Clin Microbiol Rev 2000; 13:67-82, table of contents. [PMID: 10627492 PMCID: PMC88934 DOI: 10.1128/cmr.13.1.67] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The family Flaviviridae contains three genera: Hepacivirus, Flavivirus, and Pestivirus. Worldwide, more than 170 million people are chronically infected with Hepatitis C virus and are at risk of developing cirrhosis and/or liver cancer. In addition, infections with arthropod-borne flaviviruses (such as dengue fever, Japanese encephalitis, tick-borne encephalitis, St. Louis encephalitis, Murray Valley encephalitis, West Nile, and yellow fever viruses) are emerging throughout the world. The pestiviruses have a serious impact on livestock. Unfortunately, no specific antiviral therapy is available for the treatment or the prevention of infections with members of the Flaviviridae. Ongoing research has identified possible targets for inhibition, including binding of the virus to the cell, uptake of the virus into the cell, the internal ribosome entry site of hepaciviruses and pestiviruses, the capping mechanism of flaviviruses, the viral proteases, the viral RNA-dependent RNA polymerase, and the viral helicase. In light of recent developments, the prevalence of infections caused by these viruses, the disease spectrum, and the impact of infections, different strategies that could be pursued to specifically inhibit viral targets and animal models that are available to study the pathogenesis and antiviral strategies are reviewed.
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Affiliation(s)
- P Leyssen
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Leuven, Belgium
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24
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Lance JW, Hickie I, Wakefield D, Colebatch JG, Cardoso F, Vidailhet M. An akinetic-rigid syndrome, depression, and stereotypies in a young man. Mov Disord 1998; 13:835-44. [PMID: 9756156 DOI: 10.1002/mds.870130515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
A young man is presented who developed an akinetic-rigid syndrome shortly after a minor illness. Rituals and stereoptypies were prominent. At its most severe he was unable to feed himself. There was no response to L-dopa/cardopa treatment. A course of ECT was followed by a marked improvement in his condition. Attempts to stop ECT for more than a week have led to recurrence of his bradykinesia.
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Affiliation(s)
- J W Lance
- Institute of Neurological Sciences, Prince of Wales Hospital, Sydney, Australia
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25
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Mackenzie JS, Poidinger M, Lindsay MD, Hall RA, Sammels LM. Molecular epidemiology and evolution of mosquito-borne flaviviruses and alphaviruses enzootic in Australia. Virus Genes 1995; 11:225-37. [PMID: 8828149 DOI: 10.1007/bf01728662] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Three distinct patterns in the molecular epidemiology and evolution are evident among the alphaviruses and flaviviruses enzootic in Australia. One pattern, exemplified by MVE and KUN viruses, is of a single genetic type evolving slowly and uniformly in geographically widely separated regions of Australia with no evidence of independent divergence. The second pattern, exemplified by RR virus, is of separate genotypes evolving in different geographic regions with significant nucleotide divergence between genotypes. The third pattern, exemplified by SIN virus, is of a succession of temporally related genotypes that extend over most of the Australian continent, with relatively low levels of nucleotide divergence within a genotype, and which are each replaced by the subsequent genotype. These patterns are associated in part due to the nature and dispersal of their vertebrate hosts. Nucleotide divergence rates for Australian alphaviruses are similar to those reported elsewhere. Genomic relationships between Australian flavivirus members of the JE virus serological complex and between Australian alphaviruses are discussed, and evidence is presented for a possible new genomic lineage of SIN virus.
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Affiliation(s)
- J S Mackenzie
- Department of Microbiology, University of Queensland, Brisbane, Australia
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