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Naveed A, Eertink LG, Wang D, Li F. Lessons Learned from West Nile Virus Infection:Vaccinations in Equines and Their Implications for One Health Approaches. Viruses 2024; 16:781. [PMID: 38793662 PMCID: PMC11125849 DOI: 10.3390/v16050781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024] Open
Abstract
Humans and equines are two dead-end hosts of the mosquito-borne West Nile virus (WNV) with similar susceptibility and pathogenesis. Since the introduction of WNV vaccines into equine populations of the United States of America (USA) in late 2002, there have been only sporadic cases of WNV infection in equines. These cases are generally attributed to unvaccinated and under-vaccinated equines. In contrast, due to the lack of a human WNV vaccine, WNV cases in humans have remained steadily high. An average of 115 deaths have been reported per year in the USA since the first reported case in 1999. Therefore, the characterization of protective immune responses to WNV and the identification of immune correlates of protection in vaccinated equines will provide new fundamental information about the successful development and evaluation of WNV vaccines in humans. This review discusses the comparative epidemiology, transmission, susceptibility to infection and disease, clinical manifestation and pathogenesis, and immune responses of WNV in humans and equines. Furthermore, prophylactic and therapeutic strategies that are currently available and under development are described. In addition, the successful vaccination of equines against WNV and the potential lessons for human vaccine development are discussed.
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Affiliation(s)
| | | | | | - Feng Li
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY 40546, USA; (A.N.); (L.G.E.); (D.W.)
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2
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Ben-Mostafa KK, Savini G, Di Gennaro A, Teodori L, Leone A, Monaco F, Alaoqib MMA, Rayes AA, Dayhum A, Eldaghayes I. Evidence of West Nile Virus Circulation in Horses and Dogs in Libya. Pathogens 2023; 13:41. [PMID: 38251348 PMCID: PMC10820222 DOI: 10.3390/pathogens13010041] [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: 11/06/2023] [Revised: 12/30/2023] [Accepted: 12/30/2023] [Indexed: 01/23/2024] Open
Abstract
West Nile virus (WNV) is a globally significant mosquito-borne Flavivirus that causes West Nile disease (WND). In Libya, evidence of WNV circulation has been reported in humans but never in animals. The aim of this study was to determine the seroprevalence of WNV infection in horses and dogs in Libya. In total, 574 and 63 serum samples were collected from apparently healthy, unvaccinated horses and dogs, respectively, between 2016 and 2019. A commercially available competitive enzyme-linked immunosorbent assay (c-ELISA) kit was initially used to test the collected samples for the presence of WNV Ig-G antibodies. Positive and doubtful sera were also tested using a more specific virus neutralisation assay to confirm whether the ELISA-positive results were due to WNV or other Flavivirus antibodies. The seroprevalence of WNV IgG antibodies according to ELISA was 13.2% out of 574 of total horses' samples and 30.2% out of 63 of total dogs' samples. The virus neutralisation test (VNT) confirmed that 10.8% (62/574) and 27% (17/63) were positive for WNV-neutralising titres ranging from 1:10 to 1:640. Univariable analysis using chi-square tests was conducted to measure the statistical significance of the association between the hypothesized risk factors including city, sex, breed, and age group and were then analyzed using the subsequent multivariable logistic regression model for horse samples. Age group was found to be the only significant risk factor in this study. The results of the present study provide new evidence about WNV circulation in Libya.
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Affiliation(s)
- Kholoud Khalid Ben-Mostafa
- Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, Tripoli P.O. Box 13662, Libya
- National Center for Animal Health, Tripoli P.O. Box 83252, Libya
| | - Giovanni Savini
- Department of Virology and Tissue Culture, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G.Caporale”, 64100 Teramo, Italy
| | - Annapia Di Gennaro
- Department of Virology and Tissue Culture, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G.Caporale”, 64100 Teramo, Italy
| | - Liana Teodori
- Department of Virology and Tissue Culture, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G.Caporale”, 64100 Teramo, Italy
| | - Alessandra Leone
- Department of Virology and Tissue Culture, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G.Caporale”, 64100 Teramo, Italy
| | - Federica Monaco
- Department of Virology and Tissue Culture, Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G.Caporale”, 64100 Teramo, Italy
| | - Mohammed Masoud A. Alaoqib
- Department of Internal and Infectious Diseases, Faculty of Veterinary Medicine, Omar Al-Mukhtar University, Albaida P.O. Box 919, Libya
| | - Abdunnabi A. Rayes
- Department of Internal Medicine, Faculty of Medicine, University of Tripoli, Tripoli P.O. Box 13932, Libya
| | - Abdunaser Dayhum
- Department of Preventive Medicine, Faculty of Veterinary Medicine, University of Tripoli, Tripoli P.O. Box 13662, Libya
| | - Ibrahim Eldaghayes
- Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, Tripoli P.O. Box 13662, Libya
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Laabassi F, Dheilly N, Beck C, Amaral R, Gonzalez G, Gaudaire D, Madeline A, Lecouturier F, Lecollinet S, Zientara S, Hans A, Valle-Casuso JC. Serological evidence of circulation of West Nile virus in equids in Algerian eastern drylands and its epidemiological risk factors. Comp Immunol Microbiol Infect Dis 2023; 94:101947. [PMID: 36638646 DOI: 10.1016/j.cimid.2023.101947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/07/2023] [Accepted: 01/09/2023] [Indexed: 01/12/2023]
Abstract
In order to determine the prevalence of equine infectious anemia virus (EIAV), Usutu virus (USUV), and West Nile virus (WNV) in eastern Algerian drylands, 340 sera from distinct equids have been collected from 2015 to 2017. Serological analysis for the presence of antibodies against EIAV and flaviviruses was performed using commercially available ELISAs. Sera detected positive, doubtful, or negative close to the doubtful threshold in flavivirus ELISA were tested by the virus neutralization test (VNT), using WNV and USUV strains. The prevalence of WNV antibodies with ELISA was 11.47% (39/340) against 13.53% (46/340) by WNV VNT. EIAV antibodies were not detected in any samples. WNV seroprevalence varies with species, breed and location of horses. Only, one equid was positive for both WNV and USUV neutralizing antibodies. This is the first screening on equids sera of EIAV and USUV in Algeria. This study indicate that WNV and possibly USUV have circulated/are circulating in the Algerian equine population, unlike EIAV does not seem to be present.
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Affiliation(s)
- Farouk Laabassi
- PIAD Research Team, ESPA Laboratory, Department of Veterinary, Institute of Veterinary Sciences and Agronomics Sciences, University of Batna-1, 05000 Batna, Algeria.
| | - Nolwenn Dheilly
- Anses, INRAE, Ecole Nationale Vétérinaire d'Alfort, UMR VIROLOGIE, Animal Health Laboratory, Maisons-Alfort, France.
| | - Cécile Beck
- Anses, INRAE, Ecole Nationale Vétérinaire d'Alfort, UMR VIROLOGIE, Animal Health Laboratory, Maisons-Alfort, France.
| | - Rayane Amaral
- Anses, INRAE, Ecole Nationale Vétérinaire d'Alfort, UMR VIROLOGIE, Animal Health Laboratory, Maisons-Alfort, France.
| | - Gaëlle Gonzalez
- Anses, INRAE, Ecole Nationale Vétérinaire d'Alfort, UMR VIROLOGIE, Animal Health Laboratory, Maisons-Alfort, France.
| | - Delphine Gaudaire
- ANSES-Laboratory for Animal Health in Normandy, Physiopathology and Epidemiology of Equine Diseases Unit, Goustranville, France.
| | - Anthony Madeline
- ANSES-Laboratory for Animal Health in Normandy, Physiopathology and Epidemiology of Equine Diseases Unit, Goustranville, France.
| | - Fanny Lecouturier
- ANSES-Laboratory for Animal Health in Normandy, Physiopathology and Epidemiology of Equine Diseases Unit, Goustranville, France.
| | - Sylvie Lecollinet
- Anses, INRAE, Ecole Nationale Vétérinaire d'Alfort, UMR VIROLOGIE, Animal Health Laboratory, Maisons-Alfort, France.
| | - Stéphan Zientara
- Anses, INRAE, Ecole Nationale Vétérinaire d'Alfort, UMR VIROLOGIE, Animal Health Laboratory, Maisons-Alfort, France.
| | - Aymeric Hans
- ANSES-Laboratory for Animal Health in Normandy, Physiopathology and Epidemiology of Equine Diseases Unit, Goustranville, France.
| | - José-Carlos Valle-Casuso
- ANSES-Laboratory for Animal Health in Normandy, Physiopathology and Epidemiology of Equine Diseases Unit, Goustranville, France.
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Molini U, Franzo G, Rautenbach I, Otto HV, Khaiseb S, Di Gennaro A, Ntahonshikira C, Baines I, Monaco F, Savini G, D’alterio N. Neutralising antibodies to West Nile virus detected in horses in Windhoek, Namibia. J S Afr Vet Assoc 2022. [DOI: 10.36303/jsava.2022.93.1.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Affiliation(s)
- U Molini
- Department of Para-Clinical Studies, School of Veterinary Medicine, Faculty of Health Sciences and Veterinary Medicine, University of Namibia,
Namibia
- Department of Biotechnology, Central Veterinary Laboratory,
Namibia
| | - G Franzo
- Department of Animal Medicine, Production and Health, University of Padova,
Italy
| | - I Rautenbach
- Department of Para-Clinical Studies, School of Veterinary Medicine, Faculty of Health Sciences and Veterinary Medicine, University of Namibia,
Namibia
| | - HV Otto
- Department of Para-Clinical Studies, School of Veterinary Medicine, Faculty of Health Sciences and Veterinary Medicine, University of Namibia,
Namibia
| | - S Khaiseb
- Department of Biotechnology, Central Veterinary Laboratory,
Namibia
| | - A Di Gennaro
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Teramo,
Italy
| | - C Ntahonshikira
- Department of Para-Clinical Studies, School of Veterinary Medicine, Faculty of Health Sciences and Veterinary Medicine, University of Namibia,
Namibia
| | - I Baines
- Department of Production Animal Clinical Studies, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, University of Namibia,
Namibia
| | - F Monaco
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Teramo,
Italy
| | - G Savini
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Teramo,
Italy
| | - N D’alterio
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, Teramo,
Italy
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5
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Mencattelli G, Ndione MHD, Rosà R, Marini G, Diagne CT, Diagne MM, Fall G, Faye O, Diallo M, Faye O, Savini G, Rizzoli A. Epidemiology of West Nile virus in Africa: An underestimated threat. PLoS Negl Trop Dis 2022; 16:e0010075. [PMID: 35007285 PMCID: PMC8789169 DOI: 10.1371/journal.pntd.0010075] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 01/25/2022] [Accepted: 12/09/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND West Nile virus is a mosquito-borne flavivirus which has been posing continuous challenges to public health worldwide due to the identification of new lineages and clades and its ability to invade and establish in an increasing number of countries. Its current distribution, genetic variability, ecology, and epidemiological pattern in the African continent are only partially known despite the general consensus on the urgency to obtain such information for quantifying the actual disease burden in Africa other than to predict future threats at global scale. METHODOLOGY AND PRINCIPAL FINDINGS References were searched in PubMed and Google Scholar electronic databases on January 21, 2020, using selected keywords, without language and date restriction. Additional manual searches of reference list were carried out. Further references have been later added accordingly to experts' opinion. We included 153 scientific papers published between 1940 and 2021. This review highlights: (i) the co-circulation of WNV-lineages 1, 2, and 8 in the African continent; (ii) the presence of diverse WNV competent vectors in Africa, mainly belonging to the Culex genus; (iii) the lack of vector competence studies for several other mosquito species found naturally infected with WNV in Africa; (iv) the need of more competence studies to be addressed on ticks; (iv) evidence of circulation of WNV among humans, animals and vectors in at least 28 Countries; (v) the lack of knowledge on the epidemiological situation of WNV for 19 Countries and (vii) the importance of carrying out specific serological surveys in order to avoid possible bias on WNV circulation in Africa. CONCLUSIONS This study provides the state of art on WNV investigation carried out in Africa, highlighting several knowledge gaps regarding i) the current WNV distribution and genetic diversity, ii) its ecology and transmission chains including the role of different arthropods and vertebrate species as competent reservoirs, and iii) the real disease burden for humans and animals. This review highlights the needs for further research and coordinated surveillance efforts on WNV in Africa.
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Affiliation(s)
- Giulia Mencattelli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Trento, Italy
- Center Agriculture Food Environment, University of Trento, San Michele all'Adige, Trento, Italy
| | | | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Trento, Italy
- Center Agriculture Food Environment, University of Trento, San Michele all'Adige, Trento, Italy
| | - Giovanni Marini
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Trento, Italy
| | | | | | - Gamou Fall
- Department of Virology, Fondation Institut Pasteur de Dakar, Dakar, Senegal
| | - Ousmane Faye
- Department of Virology, Fondation Institut Pasteur de Dakar, Dakar, Senegal
| | - Mawlouth Diallo
- Department of Zoology, Fondation Institut Pasteur de Dakar, Dakar, Senegal
| | - Oumar Faye
- Department of Virology, Fondation Institut Pasteur de Dakar, Dakar, Senegal
| | - Giovanni Savini
- Department of Public Health, OIE Reference Laboratory for WND, Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Annapaola Rizzoli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Trento, Italy
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6
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Srihi H, Chatti N, Ben Mhadheb M, Gharbi J, Abid N. Phylodynamic and phylogeographic analysis of the complete genome of the West Nile virus lineage 2 (WNV-2) in the Mediterranean basin. BMC Ecol Evol 2021; 21:183. [PMID: 34579648 PMCID: PMC8477494 DOI: 10.1186/s12862-021-01902-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 08/12/2021] [Indexed: 11/25/2022] Open
Abstract
Background The West Nile virus is a highly contagious agent for a wide range of hosts. Its spread in the Mediterranean region raises several questions about its origin and the risk factors underlying the virus’s dispersal. Materials and methods The present study aims to reconstruct the temporal and spatial phylodynamics of West Nile virus lineage 2 in the Mediterranean region using 75 complete genome sequences from different host species retrieved from international databases. Results This data set suggests that current strains of WNV-2 began spreading in South Africa or nearby regions in the early twentieth century, and it migrated northwards via at least one route crossing the Mediterranean to reach Hungary in the early 2000s, before spreading throughout Europe. Another introduction event, according to the data set collected and analyses performed, is inferred to have occurred in around 1978. Migratory birds constitute, among others, additional risk factors that enhance the geographical transmission of the infection.
Conclusion Our data underline the importance of the spatial–temporal tracking of migratory birds and phylodynamic reconstruction in setting up an efficient surveillance system for emerging and reemerging zoonoses in the Mediterranean region. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01902-w.
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Affiliation(s)
- Haythem Srihi
- Research Unit UR17ES30 "Genomics, Biotechnology and Antiviral Strategies", Higher Institute of Biotechnology of Monastir, University of Monastir, Tahar Hadded Avenue, PB 74, 5000, Monastir, Tunisia.
| | - Noureddine Chatti
- Research Unit UR17ES30 "Genomics, Biotechnology and Antiviral Strategies", Higher Institute of Biotechnology of Monastir, University of Monastir, Tahar Hadded Avenue, PB 74, 5000, Monastir, Tunisia
| | - Manel Ben Mhadheb
- Research Unit UR17ES30 "Genomics, Biotechnology and Antiviral Strategies", Higher Institute of Biotechnology of Monastir, University of Monastir, Tahar Hadded Avenue, PB 74, 5000, Monastir, Tunisia
| | - Jawhar Gharbi
- Research Unit UR17ES30 "Genomics, Biotechnology and Antiviral Strategies", Higher Institute of Biotechnology of Monastir, University of Monastir, Tahar Hadded Avenue, PB 74, 5000, Monastir, Tunisia.,Department of Biological Sciences, College of Science, King Faisal University, PB 400, Post Code 31982, Al-Ahsa, Saudi Arabia
| | - Nabil Abid
- Laboratory of Transmissible Diseases and Biological Active Substances LR99ES27, Faculty of Pharmacy, University of Monastir, Ibn Sina Street, 5000, Monastir, Tunisia. .,High Institute of Biotechnology of Sidi Thabet, Department of Biotechnology, University of Manouba, BiotechPôlet Sidi Thabet, PB 66, 2020, Ariana-Tunis, Tunisia.
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7
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Conze TM, Bagó Z, Revilla-Fernández S, Schlegel J, Goehring LS, Matiasek K. Tick-Borne Encephalitis Virus (TBEV) Infection in Two Horses. Viruses 2021; 13:1775. [PMID: 34578356 PMCID: PMC8472121 DOI: 10.3390/v13091775] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 08/30/2021] [Accepted: 09/02/2021] [Indexed: 12/21/2022] Open
Abstract
A final diagnosis in a horse with clinical signs of encephalopathy can be challenging despite the use of extensive diagnostics. Clinical signs are often not pathognomonic and need to be interpreted in combination with (specific) laboratory results and epidemiological data of the geographical region of the origin of the case(s). Here we describe the diagnostic pathway of tick-borne encephalitis virus infection in two horses using established molecular diagnostic methods and a novel in situ hybridization technique to differentiate between regionally important/emerging diseases for central Europe: (i) hepatoencephalopathy, (ii) Borna disease virus, and (iii) West Nile virus infections.
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Affiliation(s)
- Theresa Maria Conze
- Equine Medicine and Reproduction, Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, Ludwig-Maximilians University Munich, Veterinärstraße 13, 80539 Munich, Germany;
| | - Zoltán Bagó
- Institute for Veterinary Disease Control Mödling, Austrian Agency for Health and Food Safety GmbH (AGES), IVET, 2340 Mödling, Austria; (Z.B.); (S.R.-F.)
| | - Sandra Revilla-Fernández
- Institute for Veterinary Disease Control Mödling, Austrian Agency for Health and Food Safety GmbH (AGES), IVET, 2340 Mödling, Austria; (Z.B.); (S.R.-F.)
| | - Jürgen Schlegel
- Department of Neuropathology, Institute of Pathology, School of Medicine, Technical University Munich, Trogerstraße 18, 81675 Munich, Germany;
| | - Lutz S. Goehring
- Equine Medicine and Reproduction, Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, Ludwig-Maximilians University Munich, Veterinärstraße 13, 80539 Munich, Germany;
| | - Kaspar Matiasek
- Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians University, Veterinärstraße 13, 80539 Munich, Germany
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A Scoping Review of West Nile Virus Seroprevalence Studies among African Equids. Pathogens 2021; 10:pathogens10070899. [PMID: 34358049 PMCID: PMC8308515 DOI: 10.3390/pathogens10070899] [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: 06/29/2021] [Revised: 07/10/2021] [Accepted: 07/12/2021] [Indexed: 11/17/2022] Open
Abstract
West Nile virus (WNV) is an emerging and re-emerging zoonotic flavivirus first identified in and endemic to Africa. The virus is transmitted between birds by biting mosquitoes, with equids and humans being incidental hosts. The majority of infected incidental hosts display no or only mild clinical signs, but a fraction develop encephalitis. The aim of this scoping review was to identify and evaluate primary research on the presence of antibodies to WNV among African equids. Three bibliographic databases and the grey literature were searched. Of 283 articles identified, only 16 satisfied all the inclusion criteria. Data were collated on study design and outcomes. The overall seroprevalence reported ranged from 17.4 to 90.3%, with 1998 (35%) of the 5746 horses, donkeys and mules having screened positive for WNV antibodies. Several articles determined that seroprevalence increased significantly with age. Due to co-circulation of other flaviviruses in Africa, in the majority of studies that screened samples by ELISA, positive results were confirmed using a more specific neutralization test. However, only eight studies tested against other flaviviruses, including Potiskum, Uganda S, Wesselsbron and yellow fever virus in one, Japanese encephalitis and Usutu virus (USUV) in one, tick-borne encephalitis and USUV in one and USUV only in three. Equids are regarded as useful sentinel animals for WNV, but variation in study design poses challenges when trying to determine risk factors for, and trends in, WNV seroprevalence.
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Molini U, Franzo G, Nel H, Khaiseb S, Ntahonshikira C, Chiwome B, Baines I, Madzingira O, Monaco F, Savini G, D'Alterio N. West Nile Virus Seroprevalence in a Selected Donkey Population of Namibia. Front Vet Sci 2021; 8:681354. [PMID: 34222404 PMCID: PMC8249584 DOI: 10.3389/fvets.2021.681354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/26/2021] [Indexed: 11/21/2022] Open
Abstract
West Nile Virus (WNV) is a mosquito-borne virus enzootically maintained in birds. However, it can incidentally infect other species, leading to sometimes severe clinical consequences like in horses and especially human beings. Despite the topic relevance, the presence and distribution of WNV are currently unknown in Namibia. Several countries implement surveillance systems based on virus detection in birds, mosquitoes, and vertebrate species including horses. The present study aimed to fill this knowledge gap by serologically evaluating WNV exposure in Namibian donkeys, whose population is remarkably bigger than the horse one. Forty-seven out of 260 sampled animals showed neutralizing antibodies against WNV (18.07% [95% CI = 13.59–23.30%]), demonstrating its circulation in all country territory, although, with apparent regional differences. On the contrary, no association with animal age or sex could be identified. The present study demonstrates the widespread presence of WNV in Namibia as well as the practical utility and effectiveness of donkeys as sentinels for infection surveillance. Due to clinical relevance, vaccination campaigns should be considered for horses of high economic or genetic value. Additionally, the burden of WNV infection on human health should be carefully evaluated.
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Affiliation(s)
- Umberto Molini
- Faculty of Agriculture and Natural Resources, School of Veterinary Medicine, University of Namibia, Neudamm Campus, Windhoek, Namibia.,Central Veterinary Laboratory (CVL), Windhoek, Namibia
| | - Giovanni Franzo
- Department of Animal Medicine, Production, and Health, University of Padova, Padova, Italy
| | - Hannah Nel
- Faculty of Agriculture and Natural Resources, School of Veterinary Medicine, University of Namibia, Neudamm Campus, Windhoek, Namibia
| | | | - Charles Ntahonshikira
- Faculty of Agriculture and Natural Resources, School of Veterinary Medicine, University of Namibia, Neudamm Campus, Windhoek, Namibia
| | - Bernard Chiwome
- Faculty of Agriculture and Natural Resources, School of Veterinary Medicine, University of Namibia, Neudamm Campus, Windhoek, Namibia
| | - Ian Baines
- Faculty of Agriculture and Natural Resources, School of Veterinary Medicine, University of Namibia, Neudamm Campus, Windhoek, Namibia
| | - Oscar Madzingira
- Faculty of Agriculture and Natural Resources, School of Veterinary Medicine, University of Namibia, Neudamm Campus, Windhoek, Namibia
| | - Federica Monaco
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Giovanni Savini
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
| | - Nicola D'Alterio
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", Teramo, Italy
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10
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Alzuheir I, Fayyad A, Jalboush N, Abdallah R, Abutarbush S, Gharaibeh M, Bdarneh M, Khraim N, Helal MA, Helal BA. Seroprevalence and risk factors of West Nile virus infection in veterinarians and horses in Northern Palestine. Vet World 2021; 14:1241-1246. [PMID: 34220126 PMCID: PMC8243691 DOI: 10.14202/vetworld.2021.1241-1246] [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: 02/06/2021] [Accepted: 04/06/2021] [Indexed: 11/16/2022] Open
Abstract
Background and Aim West Nile fever (WNF) is a neurotropic, mosquito-borne disease affecting humans and domesticated animals, caused by a member of the genus Flavivirus. Over the last decades, this virus has been responsible for several cases of illness in humans and animals. The current epidemiological status of WNF in horses is insufficient, and in veterinarians, as an occupational hazard is unknown. This study aimed to investigate and determine the seroprevalence and risk factors for WNF in veterinarians and horses in Palestine. Materials and Methods In this study, serum samples from 100 veterinarians and 87 horses were collected between August 2020 and September 2020 from different cities of Northern Palestine. West Nile virus (WNV) antibodies were detected using an enzyme-linked immunosorbent assay. Results Our results showed that 60.9% of the horse serum samples were positive in all investigated cities. In horses, location is a risk factor for the seropositivity for WNF, whereas age, sex, breed, and intended use of the horses, were not associated with increased WNF seropositivity. In veterinarians, 23.0% of the serum samples were positive. Positive samples were detected in all locations, age groups, experience length, and work sectors. However, the seropositivity for WNF was not influenced by these variables. Conclusion The results revealed that WNV circulates in most regions of Palestine. Our results will help determine the risk of infection in animals and humans and control WNV transmission. Surveillance studies on humans, vectors, and animals are needed to better define endemic areas.
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Affiliation(s)
- Ibrahim Alzuheir
- Department of Veterinary Medicine, An-Najah National University, P.O. Box 7 Nablus, Palestine
| | - Adnan Fayyad
- Department of Veterinary Medicine, An-Najah National University, P.O. Box 7 Nablus, Palestine
| | - Nasr Jalboush
- Department of Veterinary Medicine, An-Najah National University, P.O. Box 7 Nablus, Palestine
| | | | - Sameeh Abutarbush
- Department of Clinical Veterinary Medical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030 Irbid, 22110 Jordan
| | - Mohammad Gharaibeh
- Department of Basic Veterinary Medical Science, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P. O. Box 3030 Irbid, 22110, Jordan
| | - Majd Bdarneh
- Department of Clinical Veterinary Medical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030 Irbid, 22110 Jordan
| | - Nimer Khraim
- Department of Veterinary Medicine, An-Najah National University, P.O. Box 7 Nablus, Palestine
| | - Mohammad Abu Helal
- Department of Public Health Sciences, Faculty of Graduate Studies, An-Najah National University, P.O. Box 7 Nablus, Palestine
| | - Belal Abu Helal
- Department of Veterinary Medicine, An-Najah National University, P.O. Box 7 Nablus, Palestine
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11
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Bertram FM, Thompson PN, Venter M. Epidemiology and Clinical Presentation of West Nile Virus Infection in Horses in South Africa, 2016-2017. Pathogens 2020; 10:pathogens10010020. [PMID: 33396935 PMCID: PMC7823741 DOI: 10.3390/pathogens10010020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/24/2020] [Accepted: 12/26/2020] [Indexed: 01/30/2023] Open
Abstract
Although West Nile virus (WNV) is endemic to South Africa (RSA), it has only become recognized as a significant cause of neurological disease in humans and horses locally in the past 2 decades, as it emerged globally. This article describes the epidemiological and clinical presentation of WNV in horses across RSA during 2016–2017. In total, 54 WNV-positive cases were identified by passive surveillance in horses with febrile and/or neurological signs at the Centre for Viral Zoonoses, University of Pretoria. They were followed up and compared to 120 randomly selected WNV-negative controls with the same case definition and during the same time period. Of the WNV-positive cases, 52% had fever, 92% displayed neurological signs, and 39% experienced mortality. Cases occurred mostly in WNV-unvaccinated horses <5 years old, during late summer and autumn after heavy rain, in the temperate to warm eastern parts of RSA. WNV-positive cases that had only neurological signs without fever were more likely to die. In the multivariable analysis, the odds of WNV infection were associated with season (late summer), higher altitude, more highly purebred animals, younger age, and failure to vaccinate against WNV. Vaccination is currently the most effective prophylactic measure to reduce WNV morbidity and mortality in horses.
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Affiliation(s)
- Freude-Marié Bertram
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa; (F.-M.B.); (P.N.T.)
| | - Peter N. Thompson
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa; (F.-M.B.); (P.N.T.)
| | - Marietjie Venter
- Centre for Viral Zoonoses, Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa
- Correspondence: ; Tel.: +27-12-319-2638
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12
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Bosco-Lauth AM, Bowen RA. West Nile Virus: Veterinary Health and Vaccine Development. JOURNAL OF MEDICAL ENTOMOLOGY 2019; 56:1463-1466. [PMID: 31549715 DOI: 10.1093/jme/tjz125] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Indexed: 06/10/2023]
Abstract
West Nile virus (WNV) (Flaviviridae: Flavivirus) was discovered in Africa more than 80 yr ago and became recognized as an avian pathogen and a cause of neurologic disease in horses largely during periodic incursions into Europe. Introduction of WNV into North America stimulated great anxiety, particularly in the equine industry, but also for pet owners and livestock producers concerned about the effect of WNV on other domestic animals. Numerous subsequent studies of naturally occurring and experimentally induced disease greatly expanded our understanding of the host range and clinical consequences of WNV infection in diverse species and led to rapid development and deployment of efficacious vaccines for horses. In addition to humans, horses are clearly the animals most frequently affected by serious, sometimes lethal disease following infection with WNV, but are dead-end hosts due to the low-magnitude viremia they develop. Dogs, cats, and livestock species including chickens are readily infected with WNV, but only occasionally develop clinical disease and are considered dead-end hosts for the virus.
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Affiliation(s)
- Angela M Bosco-Lauth
- Department of Biomedical Sciences, ARBL, Colorado State University, Fort Collins, CO
| | - Richard A Bowen
- Department of Biomedical Sciences, ARBL, Colorado State University, Fort Collins, CO
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13
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Sule WF, Oluwayelu DO, Hernández-Triana LM, Fooks AR, Venter M, Johnson N. Epidemiology and ecology of West Nile virus in sub-Saharan Africa. Parasit Vectors 2018; 11:414. [PMID: 30005653 PMCID: PMC6043977 DOI: 10.1186/s13071-018-2998-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 07/06/2018] [Indexed: 12/11/2022] Open
Abstract
West Nile virus (WNV) is the aetiological agent of the mosquito-borne zoonotic disease West Nile fever. The virus, first isolated in Uganda in 1937, evolved into two distinct lineages in sub-Saharan Africa (SSA) that subsequently spread to most continents where the virus has evolved further as evident through phylogenetic analysis of extant genomes. Numerous published reports from the past 70 years from countries in SSA indicate that the virus is endemic across the region. However, due in part to the limited availability of diagnostic methods across large areas of the continent, the human burden of WNV is poorly understood. So too are the drivers for translocation of the virus from countries south of the Sahara Desert to North Africa and Europe. Migratory birds are implicated in this translocation although the transient viraemia, measured in days, and the time taken to migrate, measured in weeks, suggest a more complex mechanism is in play. This review considers the evidence for the presence of WNV across SSA and the role of migratory birds in the emergence of the virus in other continents.
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Affiliation(s)
- Waidi F Sule
- Department of Microbiology, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Osun State, Nigeria
| | - Daniel O Oluwayelu
- Department of Veterinary Microbiology, University of Ibadan, Ibadan, Oyo State, Nigeria.,Centre for Control and Prevention of Zoonoses, University of Ibadan, Ibadan, Oyo State, Nigeria
| | | | - Anthony R Fooks
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT153NB, UK.,Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - Marietjie Venter
- Emerging Arbo and Respiratory Program, Centre for Viral Zoonosis, Department of Medical Virology, University of Pretoria, Pretoria, South Africa
| | - Nicholas Johnson
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT153NB, UK. .,Faculty of Health and Medicine, University of Surrey, Guildford, Surrey, GU27XH, UK.
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14
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Cardinale E, Bernard C, Lecollinet S, Rakotoharinome VM, Ravaomanana J, Roger M, Olive MM, Meenowa D, Jaumally MR, Melanie J, Héraud JM, Zientara S, Cêtre-Sossah C. West Nile virus infection in horses, Indian ocean. Comp Immunol Microbiol Infect Dis 2017; 53:45-49. [PMID: 28750867 DOI: 10.1016/j.cimid.2017.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/20/2017] [Accepted: 06/23/2017] [Indexed: 11/16/2022]
Abstract
The circulation of West Nile virus (WNV) in horses was investigated in the Southwest Indian ocean. In 2010, blood samples were collected from a total of 303 horses originating from Madagascar, Mauritius, Reunion and the Seychelles and tested for WNV-specific antibodies. An overall seroprevalence of 27.39% was detected in the Indian Ocean with the highest WNV antibody prevalence of 46.22% (95% CI: [37.4-55.2%]) in Madagascar. The age and origin of the horses were found to be associated with the WNV infection risk. This paper presents the first seroprevalence study investigating WN fever in horses in the Southwest Indian Ocean area and indicates a potential risk of infection for humans and animals. In order to gain a better understanding of WN transmission cycles, WNV surveillance needs to be implemented in each of the countries.
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Affiliation(s)
- E Cardinale
- CIRAD, UMR 117 ASTRE, Cyroi Platform, F-97490 Sainte Clotilde, La Réunion, France; INRA, UMR 1309 ASTRE, F-34598 Montpellier, France.
| | - C Bernard
- CIRAD, UMR 117 ASTRE, Cyroi Platform, F-97490 Sainte Clotilde, La Réunion, France; INRA, UMR 1309 ASTRE, F-34598 Montpellier, France
| | - S Lecollinet
- UMR 1161 (ANSES/INRA/ENVA), EU-RL on Equine Diseases, F- 94701 Maisons-Alfort, France
| | - V M Rakotoharinome
- Ministère auprès de la Présidence en charge de l'Agriculture, de l'Elevage, Direction des Services Vétérinaires, Ampandrianomby, Antananarivo, Madagascar
| | - J Ravaomanana
- Centre National de la Recherche Appliquée au Développement Rural (Fofifa), Département de Recherches Zootechniques et Vétérinaires, Antananarivo, Madagascar
| | - M Roger
- CIRAD, UMR 117 ASTRE, Cyroi Platform, F-97490 Sainte Clotilde, La Réunion, France; INRA, UMR 1309 ASTRE, F-34598 Montpellier, France
| | - M M Olive
- CIRAD, UMR 117 ASTRE, Cyroi Platform, F-97490 Sainte Clotilde, La Réunion, France; INRA, UMR 1309 ASTRE, F-34598 Montpellier, France
| | - D Meenowa
- Ministère des Agro-Industries, Réduit, Mauritius
| | - M R Jaumally
- Ministère des Agro-Industries, Réduit, Mauritius
| | - J Melanie
- Ministère de l'Agriculture et des ressources marines, Victoria, Seychelles
| | - J M Héraud
- Institut Pasteur de Madagascar, Unité de Virologie, BP 1274, Antananarivo 101, Madagascar
| | - S Zientara
- UMR 1161 (ANSES/INRA/ENVA), EU-RL on Equine Diseases, F- 94701 Maisons-Alfort, France
| | - C Cêtre-Sossah
- CIRAD, UMR 117 ASTRE, Cyroi Platform, F-97490 Sainte Clotilde, La Réunion, France; INRA, UMR 1309 ASTRE, F-34598 Montpellier, France
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15
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Characterization of non-lethal West Nile Virus (WNV) infection in horses: Subclinical pathology and innate immune response. Microb Pathog 2016; 103:71-79. [PMID: 28012987 DOI: 10.1016/j.micpath.2016.12.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/27/2016] [Accepted: 12/19/2016] [Indexed: 11/21/2022]
Abstract
Most natural West Nile virus (WNV) infections in humans and horses are subclinical or sub-lethal and non-encephalitic. Yet, the main focus of WNV research remains on the pathogenesis of encephalitic disease, mainly conducted in mouse models. We characterized host responses during subclinical WNV infection in horses and compared outcomes with those obtained in a novel rabbit model of subclinical WNV infection (Suen et al. 2015. Pathogens, 4: 529). Experimental infection of 10 horses with the newly emerging WNV-strain, WNVNSW2011, did not result in neurological disease in any animal but transcriptional upregulation of both type I and II interferon (IFN) was seen in peripheral blood leukocytes prior to or at the time of viremia. Likewise, transcript upregulation for IFNs, TNFα, IL1β, CXCL10, TLRs, and MyD88 was detected in lymphoid tissues, while IFNα, CXCL10, TLR3, ISG15 and IRF7 mRNA was upregulated in brains with histopathological evidence of mild encephalitis, but absence of detectable viral RNA or antigen. These responses were reproduced in the New Zealand White rabbits (Oryctolagus cuniculus) experimentally infected with WNVNSW2011, by intradermal footpad inoculation. Kinetics of the anti-WNV antibody response was similar in horses and rabbits, which for both species may be explained by the early IFN and cytokine responses evident in circulating leukocytes and lymphoid organs. Given the similarities to the majority of equine infection outcomes, immunocompetent rabbits appear to represent a valuable small-animal model for investigating aspects of non-lethal WNV infections, notably mechanisms involved in abrogating morbidity.
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16
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Lafri I, Prat CM, Bitam I, Gravier P, Besbaci M, Zeroual F, Ben-Mahdi MH, Davoust B, Leparc-Goffart I. Seroprevalence of West Nile virus antibodies in equids in the North-East of Algeria and detection of virus circulation in 2014. Comp Immunol Microbiol Infect Dis 2016; 50:8-12. [PMID: 28131384 DOI: 10.1016/j.cimid.2016.11.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 11/05/2016] [Accepted: 11/08/2016] [Indexed: 11/15/2022]
Abstract
West Nile fever (WNF) is a viral disease of wild birds transmitted by mosquitoes. Humans and equids can also be affected and suffer from meningoencephalitis. In Algeria, since the 1994 epidemic, no data on WNV circulation was available until 2012. In September 2012, a fatal human case of WNV neuro-invasive infection occurred in Jijel province. This study describes the first seroprevalence study of West Nile virus (WNV) antibodies conducted in the equine population in Algeria. During 2014, serum samples were collected from 293 equids (222 donkeys and 71 horses) asymptomatic and unvaccinated for WNV in three localities in Northeastern wetlands of Algeria. Antibodies against WNV were found in 51 samples (seroprevalence 17.4%) of sampled equids, distributed as follows: 19 (seroprevalence 26.8%) horses and 32 (seroprevalence 14.4%) donkeys. Moreover 7 horses coming from Blida, in the center of Algeria, were tested before and after an 8-months stay in North-East Algeria. We observe a seroconversion in 2 horses, showing WNV circulation in 2014 in this specific region of Algeria.
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Affiliation(s)
- Ismail Lafri
- Institut des Sciences Vétérinaires, Université de Blida 1, Algeria
| | - Christine M Prat
- IRBA-Institut de Recherche Biomédicale des Armées, French National Reference Centre for Arboviruses, Marseille, France
| | - Idir Bitam
- Ecole Nationale Supérieure Vétérinaire d'Alger, Algeria; Université M'hamed BOUGARRA, Laboratoire VALCORE, Boumerdes, Algeria; Unité de recherche sur les maladies infectieuses et tropicales émergentes (UMR 7278), Marseille, France; Laboratoire Biodiversité et Environnement: Interactions, Génomes, Université des Sciences et de la Technologie Houari Boumediene, Alger, Algeria.
| | - Patrick Gravier
- IRBA-Institut de Recherche Biomédicale des Armées, French National Reference Centre for Arboviruses, Marseille, France
| | - Mohamed Besbaci
- Institut des Sciences Vétérinaires, Université de Blida 1, Algeria; Ecole Nationale Supérieure Vétérinaire d'Alger, Algeria
| | - Fayçal Zeroual
- Département des Sciences Vétérinaires, Université d'El Tarf, Algeria
| | | | - Bernard Davoust
- Unité de recherche sur les maladies infectieuses et tropicales émergentes (UMR 7278), Marseille, France
| | - Isabelle Leparc-Goffart
- IRBA-Institut de Recherche Biomédicale des Armées, French National Reference Centre for Arboviruses, Marseille, France; UMR "Emergence des Pathologies Virales" (EPV: Aix-Marseille university - IRD 190 - Inserm 1207 - EHESP), Marseille, France
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17
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Hernández-Triana LM, Jeffries CL, Mansfield KL, Carnell G, Fooks AR, Johnson N. Emergence of west nile virus lineage 2 in europe: a review on the introduction and spread of a mosquito-borne disease. Front Public Health 2014; 2:271. [PMID: 25538937 PMCID: PMC4258884 DOI: 10.3389/fpubh.2014.00271] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 11/23/2014] [Indexed: 11/13/2022] Open
Abstract
West Nile virus (WNV) is transmitted by mosquitoes and causes fever and encephalitis in humans, equines, and occasionally wild birds. The virus was first isolated in sub-Saharan Africa where it is endemic. WNV lineage 1 has been responsible for repeated disease outbreaks in the countries of the Mediterranean basin over the past 50 years. This lineage was also introduced into North America in 1999 causing widespread human, equine, and avian mortality. WNV lineage 2, the first WNV lineage to be isolated, was believed to be restricted to sub-Saharan Africa causing a relatively mild fever in humans. However, in 2004, an investigation in Hungary of a case of encephalitis in a wild goshawk (Accipiter gentiles) resulted in the isolation of WNV lineage 2. During the summer of 2004, and in subsequent years, the virus appeared to spread locally throughout Hungary and into neighboring Austria. Subsequently, WNV lineage 2 emerged in Greece in 2010 and in Italy in 2011, involving outbreaks on the Italian mainland and Sardinia. Further spread through the Balkan countries is also suspected. Whole genome sequencing has confirmed that the virus responsible for the outbreaks in Greece and Italy was almost identical to that isolated in Hungary. However, unlike the outbreaks in Hungary, the burden of disease in Mediterranean countries has fallen upon the human population with numerous cases of West Nile fever and a relatively higher mortality rate than in previous outbreaks. The emergence of WNV lineage 2 in Europe, its over-wintering and subsequent spread over large distances illustrates the repeated threat of emerging mosquito-borne diseases. This article will review the emergence of WNV lineage 2 in Europe; consider the pathways for virus spread and the public health implications for the continent.
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Affiliation(s)
- Luis M Hernández-Triana
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
| | - Claire L Jeffries
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
| | - Karen L Mansfield
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
| | - George Carnell
- London School of Hygiene and Tropical Medicine , London , UK
| | - Anthony R Fooks
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK ; Department of Clinical Infection, University of Liverpool , Liverpool , UK
| | - Nicholas Johnson
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
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18
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Pearce MC, Venter M, Schouwstra T, Van Eeden C, Jansen van Vuren P, Paweska J, Liu B, Du Plessis A. Serum neutralising antibody response of seronegative horses against lineage 1 and lineage 2 West Nile virus following vaccination with an inactivated lineage 1 West Nile virus vaccine. J S Afr Vet Assoc 2013. [DOI: 10.4102/jsava.v84i1.1052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Lineage 2 West Nile virus (WNV) strains are endemic in South Africa and cause severe neurological disease in horses. An inactivated lineage 1 vaccine, Duvaxyn WNV, protects mice against challenge with a neuroinvasive South African lineage 2 strain of WNV. To evaluate the potential of Duvaxyn WNV to protect horses against lineage 2 strains of WNV, serum neutralising antibody responses of horses against lineage 1 WNV strain NY385/99 and lineage 2 WNV strain SPU93/01, isolated from a human with meningo-encephalitis in South Africa, were compared following vaccination with two doses of Duvaxyn WNV, 28 days apart, and a third dose one year later. Twenty-two seronegative horses were randomly assigned to two treatment groups: 16 to a vaccinated group and six retained as unvaccinated controls. Blood samples were taken from all horses on study days 0, 28, 35, 42, 49, 91, 141, 182, 231, 274, 322, 364 and 413. Primovaccination with Duvaxyn WNV resulted in high titres of serum neutralising antibodies against both strains. Following a single dose of Duvaxyn WNV on day 399, one year after primovaccination, there was a strong anamnestic response with a log25-fold rise in the titres of neutralising antibodies against strains NY385/99 and SPU93/01. These results provide further evidence that Duvaxyn WNV is likely to protect horses against infection with lineage 2 strains of WNV and that a single annual booster may be sufficient to maintain immunity against lineage 2 WNV infection in horses.
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19
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West Nile viral infection of equids. Vet Microbiol 2013; 167:168-80. [PMID: 24035480 DOI: 10.1016/j.vetmic.2013.08.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 08/15/2013] [Accepted: 08/16/2013] [Indexed: 12/14/2022]
Abstract
West Nile virus (WNV) is a flavivirus transmitted between certain species of birds and mosquito vectors. Tangential infections of equids and subsequent equine epizootics have occurred historically. Although the attack rate has been estimated to be below 10%, mortality rates can approach 50% in horses that present clinical disease. Symptoms are most commonly presenting in the form of encephalitis with ataxia as well as limb weakness, recumbency and muscle fasciculation. The most effective strategy for prevention of equine disease is proper vaccination with one of the numerous commercially available vaccines available in North America or the European Union. Recently, WNV has been increasingly associated with equine epizootics resulting from novel non-lineage-1a viruses in expanding geographic areas. However, specific experimental data on the virulence of these novel virus strains is lacking and questions remain as to the etiology of the expanded epizootics: whether it be a function of inherent virulence or ecological and/or climactic factors that could precipitate the altered epidemiological patterns observed.
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20
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Bargaoui R, Lecollinet S, Lancelot R. Mapping the Serological Prevalence Rate of West Nile fever in Equids, Tunisia. Transbound Emerg Dis 2013; 62:55-66. [DOI: 10.1111/tbed.12077] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Indexed: 11/30/2022]
Affiliation(s)
- R. Bargaoui
- Institut de la Recherche Vétérinaire de Tunisie (IRVT); Service de Virologie; Tunis Tunisie
| | - S. Lecollinet
- Agence Nationale de Sécurité Sanitaire de l'Alimentation; de l'Environnement et du Travail (ANSES), UMR n°1161 Virologie ANSES, INRA, ENVA; Maisons-Alfort France
| | - R. Lancelot
- CIRAD, UMR n°15 CMAEE (CIRAD, INRA); Montpellier France
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21
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Minke J, Siger L, Cupillard L, Powers B, Bakonyi T, Boyum S, Nowotny N, Bowen R. Protection provided by a recombinant ALVAC®-WNV vaccine expressing the prM/E genes of a lineage 1 strain of WNV against a virulent challenge with a lineage 2 strain. Vaccine 2011; 29:4608-12. [DOI: 10.1016/j.vaccine.2011.04.058] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 04/11/2011] [Accepted: 04/17/2011] [Indexed: 11/29/2022]
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22
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Kutasi O, Bakonyi T, Lecollinet S, Biksi I, Ferenczi E, Bahuon C, Sardi S, Zientara S, Szenci O. Equine encephalomyelitis outbreak caused by a genetic lineage 2 West Nile virus in Hungary. J Vet Intern Med 2011; 25:586-91. [PMID: 21457323 DOI: 10.1111/j.1939-1676.2011.0715.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND The spread of lineage 2 West Nile virus (WNV) from sub-Saharan regions to Europe and the unpredictable change in pathogenicity indicate a potential public and veterinary health threat and requires scientific awareness. OBJECTIVES To describe the results of clinical and virological investigations of the 1st outbreak of a genetic lineage 2 WNV encephalomyelitis in horses. ANIMALS Seventeen horses with neurologic signs. METHODS Information regarding signalment, clinical signs, and outcome was obtained for each animal. Serology was performed in 15 cases, clinicopathological examination in 7 cases, and cerebrospinal fluid was collected from 2 horses. Histopathology was carried out in 4 horses, 2 of which were assessed for the presence of WNV in their nervous system. RESULTS WNV neutralizing antibody titers were between 10 and 270 (median, 90) and the results of other serological assays were in agreement with those of the plaque reduction neutralization test. Common signs included ataxia, weakness, asymmetric gait, muscle tremors, hypersensitivity, cranial nerve deficits, and recumbency. Twelve animals survived. Amplicons derived from the infection-positive specimens allowed molecular characterization of the viral strain. CONCLUSIONS AND CLINICAL IMPORTANCE From our results, we conclude that this outbreak was caused by a lineage 2 WNV strain, even though such strains often are considered nonpathogenic. Neurological signs and survival rates were similar to those reported for lineage 1 virus infections. The disease occurrence was not geographically limited as had been the typical case during European outbreaks; this report describes a substantial northwestern spread of the pathogen.
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Affiliation(s)
- O Kutasi
- Large Animal Clinic, Faculty of Veterinary Science, Szent Istvan University, Ullo, Hungary.
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23
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Venter M, Swanepoel R. West Nile virus lineage 2 as a cause of zoonotic neurological disease in humans and horses in southern Africa. Vector Borne Zoonotic Dis 2011; 10:659-64. [PMID: 20854018 DOI: 10.1089/vbz.2009.0230] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
West Nile virus (WNV) is widely distributed in South Africa, but since a few cases of neurological disease have been reported from this region, endemic lineage 2 strains were postulated to be of low virulence. Several cases of nonfatal encephalitis in humans as well as fatal cases in a foal, dog, and ostrich chicks have, however, been associated with lineage 2 WNV in South Africa. The pathogenesis of lineage 2 WNV strains was investigated using mouse neuroinvasive experiments, gene expression experiments, and genome sequence comparisons which indicated that lineage 2 strains that are highly pathogenic exist. To determine whether cases of WNV were being missed in South Africa, horses with fever and neurological disease were investigated. Several cases of WNV were identified, all associated with severe neurological disease, 85% of which had to be euthanized or died. All cases positive by RT-PCR were shown to belong to lineage 2 WNV by DNA sequencing and phylogenetic analysis. Two cases of occupational infection were investigated, including a case of zoonotic transmission to a veterinarian who performed an autopsy on one of the horses as well as a laboratory infection after a needle stick injury with a neuroinvasive lineage 2 strain. Both resulted in neurological disease. Cytokine expression was investigated in the second case to assess the immunopathogenesis of WNV. Collectively, these studies suggest that lineage 2 WNV may be significantly under estimated as a cause of neurological disease in South Africa.
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Affiliation(s)
- Marietjie Venter
- Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
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24
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Chausov EV, Ternovoi VA, Protopopova EV, Konovalova SN, Kononova YV, Pershikova NL, Moskvitina NS, Romanenko VN, Ivanova NV, Bolshakova NP, Moskvitin SS, Korobitsin IG, Gashkov SI, Tiutenkov OY, Kuranova VN, Kravchenko LB, Suchkova NG, Agulova LP, Loktev VB. Genetic diversity of tick-borne pathogenes in Tomsk and environs. ACTA ACUST UNITED AC 2010. [DOI: 10.1134/s0013873810020090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Venter M, Human S, Zaayman D, Gerdes GH, Williams J, Steyl J, Leman PA, Paweska JT, Setzkorn H, Rous G, Murray S, Parker R, Donnellan C, Swanepoel R. Lineage 2 west nile virus as cause of fatal neurologic disease in horses, South Africa. Emerg Infect Dis 2009; 15:877-84. [PMID: 19523285 PMCID: PMC2727306 DOI: 10.3201/eid1506.081515] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Serologic evidence suggests that West Nile virus (WNV) is widely distributed in horses in southern Africa. However, because few neurologic cases have been reported, endemic lineage 2 strains were postulated to be nonpathogenic in horses. Recent evidence suggests that highly neuroinvasive lineage 2 strains exist in humans and mice. To determine whether neurologic cases are being missed in South Africa, we tested 80 serum or brain specimens from horses with unexplained fever (n = 48) and/or neurologic signs (n = 32) for WNV. From March 2007 through June 2008, using reverse transcription-PCR (RT-PCR) and immunoglobulin (Ig) M ELISA, we found WNV RNA or IgM in 7/32 horses with acute neurologic disease; 5 horses died or were euthanized. In 5/7 horses, no other pathogen was detected. DNA sequencing for all 5 RT-PCR-positive cases showed the virus belonged to lineage 2. WNV lineage 2 may cause neurologic disease in horses in South Africa.
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Gardner IA, Wong SJ, Ferraro GL, Balasuriya UB, Hullinger PJ, Wilson WD, Shi PY, MacLachlan NJ. Incidence and effects of West Nile virus infection in vaccinated and unvaccinated horses in California. Vet Res 2007; 38:109-16. [PMID: 17274156 DOI: 10.1051/vetres:2006045] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A prospective cohort study was used to estimate the incidence of West Nile virus (WNV) infection in a group of unvaccinated horses (n = 37) in California and compare the effects of natural WNV infection in these unvaccinated horses to a group of co-mingled vaccinated horses (n = 155). Horses initially were vaccinated with either inactivated whole virus (n = 87) or canarypox recombinant (n = 68) WNV vaccines during 2003 or 2004, prior to emergence of WNV in the region. Unvaccinated horses were serologically tested for antibodies to WNV by microsphere immunoassay incorporating recombinant WNV E protein (rE MIA) in December 2003, December 2004, and every two months thereafter until November 2005. Clinical neurologic disease attributable to WNV infection (West Nile disease (WND)) developed in 2 (5.4%) of 37 unvaccinated horses and in 0 of 155 vaccinated horses. One affected horse died. Twenty one (67.7%) of 31 unvaccinated horses that were seronegative to WNV in December, 2004 seroconverted to WNV before the end of the study in November, 2005. Findings from the study indicate that currently-available commercial vaccines are effective in preventing WND and their use is financially justified because clinical disease only occurred in unvaccinated horses and the mean cost of each clinical case of WND was approximately 45 times the cost of a 2-dose WNV vaccination program.
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Affiliation(s)
- Ian A Gardner
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Reisen WK, Fang Y, Martinez VM. Effects of temperature on the transmission of west nile virus by Culex tarsalis (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2006; 43:309-17. [PMID: 16619616 DOI: 10.1603/0022-2585(2006)043[0309:eotott]2.0.co;2] [Citation(s) in RCA: 183] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Culex tarsalis Coquillett females were infected with the NY99 strain of West Nile virus (family Flaviviridae, genus Flavivirus, WNV) and then incubated under constant temperatures of 10-30 degrees C. At selected time intervals, transmission was attempted using an in vitro capillary tube assay. The median time from imbibing an infectious bloodmeal until infected females transmitted WNV (median extrinsic incubation period, EIP50) was estimated by probit analysis. By regressing the EIP rate (inverse of EIP50) as a function of temperature from 14 to 30 degrees C, the EIP was estimated to require 109 degree-days (DD) and the point of zero virus development (x-intercept) was estimated to be 14.3 degrees C. The resulting degree-day model showed that the NY99 WNV strain responded to temperature differently than a lineage II strain of WNV from South Africa and approximated our previous estimates for St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus, SLEV). The invading NY99 WNV strain therefore required warm temperatures for efficient transmission. The time for completion of the EIP was estimated monthly from temperatures recorded at Coachella Valley, Los Angeles, and Kern County, California, during the 2004 epidemic year and related to the duration of the Cx. tarsalis gonotrophic cycle and measures of WNV activity. Enzootic WNV activity commenced after temperatures increased, the duration of the EIP decreased, and virus potentially was transmitted in two or less gonotrophic cycles. Temperatures in the United States during the epidemic summers of 2002-2004 indicated that WNV dispersal and resulting epicenters were linked closely to above-average summer temperatures.
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Affiliation(s)
- William K Reisen
- Center for Vectorborne Diseases, Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
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Reisen WK, Fang Y, Martinez VM. Effects of temperature on the transmission of west nile virus by Culex tarsalis (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2006. [PMID: 16619616 DOI: 10.1093/jmedent/43.2.309] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Culex tarsalis Coquillett females were infected with the NY99 strain of West Nile virus (family Flaviviridae, genus Flavivirus, WNV) and then incubated under constant temperatures of 10-30 degrees C. At selected time intervals, transmission was attempted using an in vitro capillary tube assay. The median time from imbibing an infectious bloodmeal until infected females transmitted WNV (median extrinsic incubation period, EIP50) was estimated by probit analysis. By regressing the EIP rate (inverse of EIP50) as a function of temperature from 14 to 30 degrees C, the EIP was estimated to require 109 degree-days (DD) and the point of zero virus development (x-intercept) was estimated to be 14.3 degrees C. The resulting degree-day model showed that the NY99 WNV strain responded to temperature differently than a lineage II strain of WNV from South Africa and approximated our previous estimates for St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus, SLEV). The invading NY99 WNV strain therefore required warm temperatures for efficient transmission. The time for completion of the EIP was estimated monthly from temperatures recorded at Coachella Valley, Los Angeles, and Kern County, California, during the 2004 epidemic year and related to the duration of the Cx. tarsalis gonotrophic cycle and measures of WNV activity. Enzootic WNV activity commenced after temperatures increased, the duration of the EIP decreased, and virus potentially was transmitted in two or less gonotrophic cycles. Temperatures in the United States during the epidemic summers of 2002-2004 indicated that WNV dispersal and resulting epicenters were linked closely to above-average summer temperatures.
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Affiliation(s)
- William K Reisen
- Center for Vectorborne Diseases, Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
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29
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Kuno G, Chang GJJ. Biological transmission of arboviruses: reexamination of and new insights into components, mechanisms, and unique traits as well as their evolutionary trends. Clin Microbiol Rev 2005; 18:608-37. [PMID: 16223950 PMCID: PMC1265912 DOI: 10.1128/cmr.18.4.608-637.2005] [Citation(s) in RCA: 189] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Among animal viruses, arboviruses are unique in that they depend on arthropod vectors for transmission. Field research and laboratory investigations related to the three components of this unique mode of transmission, virus, vector, and vertebrate host, have produced an enormous amount of valuable information that may be found in numerous publications. However, despite many reviews on specific viruses, diseases, or interests, a systematic approach to organizing the available information on all facets of biological transmission and then to interpret it in the context of the evolutionary process has not been attempted before. Such an attempt in this review clearly demonstrates tremendous progress made worldwide to characterize the viruses, to comprehend disease transmission and pathogenesis, and to understand the biology of vectors and their role in transmission. The rapid progress in molecular biologic techniques also helped resolve many virologic puzzles and yielded highly valuable data hitherto unavailable, such as characterization of virus receptors, the genetic basis of vertebrate resistance to viral infection, and phylogenetic evidence of the history of host range shifts in arboviruses. However, glaring gaps in knowledge of many critical subjects, such as the mechanism of viral persistence and the existence of vertebrate reservoirs, are still evident. Furthermore, with the accumulated data, new questions were raised, such as evolutionary directions of virus virulence and of host range. Although many fundamental questions on the evolution of this unique mode of transmission remained unresolved in the absence of a fossil record, available observations for arboviruses and the information derived from studies in other fields of the biological sciences suggested convergent evolution as a plausible process. Overall, discussion of the diverse range of theories proposed and observations made by many investigators was found to be highly valuable for sorting out the possible mechanism(s) of the emergence of arboviral diseases.
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Affiliation(s)
- Goro Kuno
- Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, USA.
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Ward MP. Epidemic West Nile virus encephalomyelitis: a temperature-dependent, spatial model of disease dynamics. Prev Vet Med 2005; 71:253-64. [PMID: 16112761 DOI: 10.1016/j.prevetmed.2005.07.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Since first being detected in New York in 1999, West Nile virus (WNV) has spread throughout the United States and more than 20,000 cases of equine WNV encephalomyelitis have been reported. A spatial model of disease occurrence was developed, using data from an outbreak of serologically confirmed disease in an unvaccinated population of horses at 108 locations in northern Indiana between 3 August and 17 October 2002. Daily maximum temperature data were recorded at meteorological stations surrounding the study area. The distribution of the total number of degree-days elapsing between July 4 and the date of diagnosis of each case was best described by a normal distribution (mean=5243 degrees F, S.D.=1047). The days on which the average risk was >25, >50 and >75% were predicted (versus observed) to occur on August 23 (August 9), August 31 (September 2) and September 9 (September 9). The epidemic was predicted to occur 3 days earlier, or 4 days later, than observed if temperatures in the study area were uniformly increased, or decreased, by 5 degrees F, respectively. Maps indicated that WNV encephalomyelitis risk always remained greater in the northwest quadrant of the study area. Since WNV might exist at a hypoendemic level of infection, and occasionally re-emerge as a cause of epidemics in equine populations, by identifying factors that contributed to this epidemic, the potential impact of future epidemics can be reduced. Such studies rely on a GIS framework, availability of meteorological and possibly remotely sensed data and information on host and landscape factors. An early-warning system for WNV transmission in equine populations could be developed.
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Affiliation(s)
- Michael P Ward
- Department of Veterinary Pathobiology, Purdue University, West Lafayette, IN 47907-2027, USA.
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Nelson DM, Gardner IA, Chiles RF, Balasuriya UB, Eldridge BF, Scott TW, Reisen WK, Maclachlan NJ. Prevalence of antibodies against Saint Louis encephalitis and Jamestown Canyon viruses in California horses. Comp Immunol Microbiol Infect Dis 2004; 27:209-15. [PMID: 15001316 DOI: 10.1016/j.cimid.2003.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2003] [Indexed: 11/28/2022]
Abstract
Jamestown Canyon (JC) and Saint Louis encephalitis (SLE) viruses are mosquito-transmitted viruses that have long been present in California. The objective of this study was to determine the seroprevalence of these two viruses in horses prior to the introduction of West Nile (WN) virus. Approximately 15% of serum samples collected in 1998 from 425 horses on 44 equine operations horses throughout California had serum antibodies to JC virus, whereas antibodies were not detected to SLE virus. The results indicate that horses in California were commonly infected prior to 1998 with mosquito-transmitted Bunyaviruses that are identical or closely related to JC virus, but not with SLE virus. The different seroprevalence of SLE and JC viruses in horses likely reflects the unique ecology of each virus, and it is predicted that WN virus will have a wider distribution in California than closely related SLE virus.
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Affiliation(s)
- Dana M Nelson
- Animal and Plant Health Inspection Service, Veterinary Services, U.S. Department of Agriculture, California and Nevada Area Office, 9850 Micron Avenue, Suite E, Sacramento, CA 95827, USA
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Wood JLN, Newton JR, Daly J, Park AW, Mumford JA. It's all in the mix: infection transmission in populations. Equine Vet J 2003; 35:526-8. [PMID: 14515949 DOI: 10.2746/042516403775467315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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