Epidemiology and Clinical Manifestation of West Nile Virus Infections of Equines in Hungary, 2007-2020

Viruses. 2022 Nov 18;14(11):2551. doi: 10.3390/v14112551.


West Nile virus (WNV) is an emerging pathogen in Hungary, causing severe outbreaks in equines and humans since 2007. The aim of our study was to provide a comprehensive report on the clinical signs of West Nile neuroinvasive disease (WNND) in horses in Hungary. Clinical details of 124 confirmed equine WNND cases were collected between 2007 and 2019. Data about the seasonal and geographical presentation, demographic data, clinical signs, treatment protocols, and disease progression were evaluated. Starting from an initial case originating from the area of possible virus introduction by migratory birds, the whole country became endemic with WNV over the subsequent 12 years. The transmission season did not expand significantly during the data collection period, but vaccination protocols should be always reviewed according to the recent observations. There was not any considerable relationship between the occurrence of WNND and age, breed, or gender. Ataxia was by far the most common neurologic sign related to the disease, but weakness, behavioral changes, and muscle fasciculation appeared frequently. Apart from recumbency combined with inappetence, no other clinical sign or treatment regime correlated with survival. The survival rate showed a moderate increase throughout the years, possibly due to the increased awareness of practitioners.

Keywords: Equidae; West Nile neuroinvasive disease; West Nile virus; emerging; endemic; epidemiology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Disease Outbreaks / veterinary
  • Horse Diseases* / epidemiology
  • Horses
  • Humans
  • Hungary / epidemiology
  • West Nile Fever* / epidemiology
  • West Nile Fever* / veterinary
  • West Nile virus* / genetics

Grants and funding

This research and the APC were funded by Recovery and Resilience Facility (RRF), financed un-der the National Recovery Fund budget estimate, RRF-2.3.1-21 funding scheme, grant number RRF-2.3.1-21-2022-00001. The research work of O.F. was partially supported by European Social Fund No. EFOP-3.6.3-VEKOP-16-2017-0005. Project no. RRF-2.3.1-21-2022-00001 was implemented with the support provided by the Recovery and Resilience Facility (RRF), financed under the National Recovery Fund budget estimate, RRF-2.3.1-21 funding scheme. The project was supported by the European Union and co-financed by the European Social Fund (grant agreement No. EFOP-3.6.3-VEKOP-16-2017-0005, project title: “Strengthening the scientific replacement by supporting the academic workshops and programs of students, developing a mentoring process”).