We report details of the first seven equine cases of confirmed West Nile neuroinvasive disease in Austria. The cases presented during summer and autumn of 2016 (n = 2), 2017 (n = 3) and 2018 (n = 2). All horses showed gait abnormalities and 6 of 7 horses exhibited fasciculations and/or tremors, and we provide video recordings of these. Three horses also showed cranial nerve involvement. Following rapid improvement, three horses were discharged. Four horses were euthanized due to the severity of clinical signs and subjected to neuropathological examination. West Nile virus (WNV) lineage 2 nucleic acid was detected in 5 of 7 horses, and WNV-specific neutralizing antibodies in all 7 horses. In addition, serologic evidence of WNV infection was found in two out of fourteen in-contact horses. Horses may be considered a sentinel species for human WNV infections, integrating human and veterinary medicine and thus contributing to the one health concept.

Department of Basic Medical Sciences College of Medicine Mohammed Bin Rashid University of Medicine and Health Sciences Dubai UAE

Institute for Veterinary Disease Control Mödling Austrian Agency for Health and Food Safety Ltd Mödling Austria

Institute of Vertebrate Biology Czech Academy of Sciences Brno Czech Republic

Section Equine Internal Medicine University Equine Hospital University of Veterinary Medicine Vienna Vienna Austria

Viral Zoonoses Emerging and Vector Borne Infections Group Institute of Virology University of Veterinary Medicine Vienna Vienna Austria

Zobrazit více v PubMed

Aberle, S. W. , Stiasny, K. , Aberle, J. H. , Kolodziejek, J. , Nowotny, N. , Jungbauer, C. , … Hourfar, M. K. (2018). Increase in human west nile and usutu virus infections, Austria, 2018. Eurosurveillance, 23(43), 3–8. 10.2807/1560-7917.ES.2018.23.43.1800545 PubMed DOI PMC

Bakonyi, T. , Ferenczi, E. , Erdélyi, K. , Kutasi, O. , Csörgo, T. , Seidel, B. , … Nowotny, N. (2013). Explosive spread of a neuroinvasive lineage 2 West Nile virus in Central Europe, 2008/2009. Veterinary Microbiology, 165(1–2), 61–70. 10.1016/j.vetmic.2013.03.005 PubMed DOI

Bakonyi, T. , Ivanics, É. , Erdélyi, K. , Ursu, K. , Ferenczi, E. , Weissenböck, H. , & Nowotny, N. (2006). Lineage 1 and 2 strains of encephalitic West Nile virus, Central Europe. Emerging Infectious Diseases, 12(4), 618–623. 10.3201/eid1204.051379 PubMed DOI PMC

Bakonyi, T. , Kolodziejek, J. , Dimmel, K. , Nowotny, N. , Jungbauer, C. , Aberle, S. W. , … Allerberger, F. (2017). Usutu virus infections among blood donors, Austria, july and august 2017 – Raising awareness for diagnostic challenges. Eurosurveillance, 22(41), 1–6. 10.2807/1560-7917.ES.2017.22.41.17-00644 PubMed DOI PMC

Beck, C. , Jimenez‐Clavero, M. A. , Leblond, A. , Durand, B. , Nowotny, N. , Leparc‐Goffart, I. , … Lecollinet, S. (2013). Flaviviruses in Europe: Complex circulation patterns and their consequences for the diagnosis and control of west nile disease. International Journal of Environmental Research and Public Health, 10(11), 6049–6083. 10.3390/ijerph10116049 PubMed DOI PMC

Bielefeldt‐Ohmann, H. , Bosco‐Lauth, A. , Hartwig, A. E. , Uddin, M. J. , Barcelon, J. , Suen, W. W. , … Bowen, R. A. (2017). Characterization of non‐lethal West Nile Virus (WNV) infection in horses: Subclinical pathology and innate immune response. Microbial Pathogenesis, 103, 71–79. 10.1016/j.micpath.2016.12.018 PubMed DOI

Bouzalas, I. G. , Diakakis, N. , Chaintoutis, S. C. , Brellou, G. D. , Papanastassopoulou, M. , Danis, K. , Dovas, C. I. (2016). Emergence of equine West Nile virus in Central Macedonia, Greece, 2010. Transboundary and Emerging Diseases, 63(6), e219–e227. 10.1111/tbed.12334 PubMed DOI

Bunning, M. L. , Bowen, R. A. , Bruce Cropp, C. , Sullivan, K. G. , Davis, B. S. , Komar, N. , … Mitchell, C. J. (2002). Experimental infection of horses with West Nile virus. Emerging Infectious Diseases, 8(4), 380–386. 10.3201/eid0804.010239 PubMed DOI PMC

Carod‐Artal, F. J. (2018). Infectious diseases causing autonomic dysfunction. Clinical Autonomic Research, 28(1), 67–81. 10.1007/s10286-017-0452-4 PubMed DOI

Castillo‐Olivares, J. , Mansfield, K. L. , Phipps, L. P. , Johnson, N. , Tearle, J. , & Fooks, A. R. (2011). Antibody response in horses following experimental infection with west nile virus lineages 1 and 2. Transboundary and Emerging Diseases, 58(3), 206–212. 10.1111/j.1865-1682.2010.01197.x PubMed DOI

Danis, K. , Papa, A. , Theocharopoulos, G. , Dougas, G. , Athanasiou, M. , Detsis, M. , … Panagiotopoulos, T. (2011). Outbreak of West Nile virus infection in Greece, 2010. Emerging Infectious Diseases, 17(10), 1868–1872. 10.3201/eid1710.110525 PubMed DOI PMC

European Commission (2007). 2007/782/EC: Commission Decision of 30 November 2007 approving annual and multi-annual national programmes and the financial contribution from the Community for the eradication, control and monitoring of certain animal diseases and zoonoses, presented by the Member States for 2008 and following years (notified under document number C (2007) 5776). Retrieved from: https://eur-lex.europa.eu/legal-content/EN/TXT/?qxml:id=1576843625178&uri=CELEX:32007D0782

European Commission (2012). Commission implementing decision of 8 August 2012 amending Decision 2002/253/EC laying down case definitions for reporting communicable diseases to the Community network under Decision No 2119/98/EC of the European Parliament and of the Council. Official Journal of the European Union. Luxembourg: Publications Office of the European Union; 27.9.2012: L 262. Retrieved from: https://eur-lex.europa.eu/legal-content/EN/ALL/?uri=CELEX:32012D0737

Hubálek, Z. , & Halouzka, J. (1999). West Nile fever–a reemerging mosquito‐borne viral disease in Europe. Emerging Infectious Diseases, 5(5), 643–650. 10.3201/eid0505.990506 PubMed DOI PMC

Hubálek, Z. , Kříž, B. , & Halouzka, J. (2011). Serologic survey of humans for flavivirus West Nile in Southern Moravia (Czech Republic). Central European Journal of Public Health, 19(3), 131–133. 10.1089/vbz.2007.0283 PubMed DOI

Kolodziejek, J. , Jungbauer, C. , Aberle, S. W. , Allerberger, F. , Bagó, Z. , Camp, J. V. , … Nowotny, N. (2018). Integrated analysis of human‐animal‐vector surveillance: West Nile virus infections in Austria, 2015–2016. Emerging Microbes and Infections, 7(1), 1–15. 10.1038/s41426-018-0021-5 PubMed DOI PMC

Kolodziejek, J. , Marinov, M. , Kiss, B. J. , Alexe, V. , & Nowotny, N. (2014). The complete sequence of a West Nile virus lineage 2 Strain detected in a Hyalomma marginatum marginatum tick collected from a song Thrush (Turdus philomelos) in Eastern Romania in 2013 revealed closest genetic relationship to strain Volgograd 2007. PLoS ONE, 9(10), e109905–10.1371/journal.pone.0109905 PubMed DOI PMC

Kolodziejek, J. , Seidel, B. , Jungbauer, C. , Dimmel, K. , Kolodziejek, M. , Rudolf, I. , … Nowotny, N. (2015). West Nile virus positive blood donation and subsequent entomological investigation, Austria, 2014. PLoS ONE, 10(5), 1–14. 10.1371/journal.pone.0126381 PubMed DOI PMC

Kutasi, O. , Bakonyi, T. , Lecollinet, S. , Biksi, I. , Ferenczi, E. , Bahuon, C. , … Szenci, O. (2011). Equine encephalomyelitis outbreak caused by a genetic lineage 2 West Nile virus in Hungary. Journal of Veterinary Internal Medicine, 25(3), 586–591. 10.1111/j.1939-1676.2011.0715.x PubMed DOI

Ostlund, E. N. , Crom, R. L. , Pedersen, D. D. , Johnson, D. J. , Williams, W. O. , & Schmitt, B. J. (2001). Equine West Nile encephalitis, United States. Emerging Infectious Diseases, 7(4), 665–669. 10.3201/eid0704.017412 PubMed DOI PMC

Papa, A. , Danis, K. , Tsergouli, K. , Tsioka, K. , & Gavana, E. (2011). Development time of IgG antibodies to West Nile virus. Archives of Virology, 156(9), 1661–1663. 10.1007/s00705-011-1014-z PubMed DOI

Porter, M. B. , Long, M. , Gosche, D. G. , Schott, H. M. , Hines, M. T. , Rossano, M. , & Sellon, D. C. (2004). Immunoglobulin M‐capture enzyme‐linked immunosorbent assay testing of cerebrospinal fluid and serum from horses exposed to West Nile virus by vaccination or natural infection. Journal of Veterinary Internal Medicine, 18(6), 866–870. PubMed

Porter, R. S. , Leblond, A. , Lecollinet, S. , Tritz, P. , Cantile, C. , Kutasi, O. , … Saegerman, C. (2011). Clinical diagnosis of west nile fever in equids by classification and regression tree (CART) analysis and comparative study of clinical appearance in three European countries. Transboundary and Emerging Diseases, 58(3), 197–205. 10.1111/j.1865-1682.2010.01196.x PubMed DOI

Rushton, J. O. , Lecollinet, S. , Hubálek, Z. , Svobodová, P. , Lussy, H. , & Nowotny, N. (2013). Tick‐borne encephalitis virus in horses, Austria, 2011. Emerging Infectious Diseases, 19(4), 635–637. 10.3201/eid1904.121450 PubMed DOI PMC

Sejvar, J. J. (2014). Clinical manifestations and outcomes of West Nile virus infection. Viruses, 6(2), 606–623. 10.3390/v6020606 PubMed DOI PMC

Stiasny, K. , Aberle, S. W. , & Heinzl, F. X. (2013). Retrospective identification of human cases of west nile virus infection in Austria (2009 to 2010) by serological differentiation from Usutu and other flavivirus infections. Eurosurveillance, 18(43), 2061420614 10.2807/1560-7917.ES2013.18.43.20614 PubMed DOI

Tewari, D. , Kim, H. , Feria, W. , Russo, B. , & Acland, H. (2004). Detection of West Nile virus using formalin fixed paraffin embedded tissues in crows and horses: Quantification of viral transcripts by real‐time RT‐PCR. Journal of Clinical Virology, 30(4), 320–325. 10.1016/j.jcv.2004.01.003 PubMed DOI

Wang, H. , Siddharthan, V. , Hall, J. O. , & Morrey, J. D. (2011). Autonomic nervous dysfunction in hamsters infected with west nile virus. PLoS ONE, 6(5), e19575 10.1371/journal.pone.0019575 PubMed DOI PMC

Weissenböck, H. , Hubálek, Z. , Halouzka, J. , Pichlmair, A. , Maderner, A. , Fragner, K. , … Nowotny, N. (2003). Screening for West Nile virus infections of susceptible animal species in Austria. Epidemiology and Infection, 131, 1023–1027. 10.1017/S0950268803001031 PubMed DOI PMC

Wodak, E. , Richter, S. , Bagó, Z. , Revilla‐Fernández, S. , Weissenböck, H. , Nowotny, N. , & Winter, P. (2011). Detection and molecular analysis of West Nile virus infections in birds of prey in the eastern part of Austria in 2008 and 2009. Veterinary Microbiology, 149(3–4), 358–366. 10.1016/j.vetmic.2010.12.012 PubMed DOI

Young, J. J. , Coulombier, D. , & Domanović, D. , European Union West Nile Fever Working Group , Zeller, H. , & Gossner, C. M. (2019). One Health approach for West Nile virus surveillance in the European Union: Relevance of equine data for blood safety. Eurosurveillance, 24(16). pii:1800349 10.2807/1560-7917.ES.2019.24.16.1800349 PubMed DOI PMC

Zehender, G. , Veo, C. , Ebranati, E. , Carta, V. , Rovida, F. , Percivalle, E. , … Galli, M. (2017). Reconstructing the recent West Nile virus lineage 2 epidemic in Europe and Italy using discrete and continuous phylogeography. PLoS ONE, 12(7), 1–16. 10.1371/journal.pone.0179679 PubMed DOI PMC

Ziegler, U. , Angenvoort, J. , Fischer, D. , Fast, C. , & Eiden, M. , Rodriguez, A. V. , Groschup, M. H. (2013). Pathogenesis of West Nile virus lineage 1 and 2 in experimentally infected large falcons. Veterinary Microbiology, 161(3‐4), 263–273. 10.1016/j.vetmic.2012.07.041 PubMed DOI

West Nile Virus and Tick-Borne Encephalitis Virus Are Endemic in Equids in Eastern Austria