Veterinary/zoology session

West-Nile virus, which is part of Flavivirus gene and Flaviviridae family, targets mainly birds, horses and humans. The typical symptoms range from mild fever to serious neurological disorders. There are two main genetic lines of the virus: Linege 1 and 2. Linege 1 is found all over the world but it only causes serious public and animal health problems in North America. Linege 2 was isolated earlier only in Africa and Madagascar.

The first epidemiological case in Hungary was in goose in the eastern part of the country in 2003. Since then, the virus was also isolated in that region from predatory birds which showed neurological symptoms. Even though the horse is a sensitive animal to this disease, until 2007 no horses were diagnosed with West-Nile virus. Unfortunately this has changed in the past two years: two illnesses in 2007 and 18 in 2008 were detected.

In this study, we summarized all hungarian West-Nile virus cases in horses with special attention to the clinical aspects. After identifying the pathogenic agents, it seems that in Hungary the Linege 2 was the causative agent of the neurological disorders. The epidemic case of 2008 is truly unique in the international literature since Linege 2. has never been identified to cause a disease which affects multiple horses in an expanded geographical

region.

In the second part of our study, we collected multiple serological samples, from horses living in or near the area from where the already diagnosed horses originated, to estimate the spread and pathogenesis of the virus and also the death rate.

Presumably due to global warming and the always changing climatic factors, West-Nile virus became an endemic disease in Hungary and it seems that from the east, where it enteres the country, the disease is spreading to the north-western direction. The prevention of the West-Nile virus caused neurological diseases would be easier then the treatment of them, therefore it’s extremely important that the veterinarians and horse owners recieve the adequate and accurate information about this new danger.