Molecular determination of west nile virus, equine herpesvirus 1 and herpesvirus 4 in feral horses in Turkey

Abstract

West Nile Virus (WNV), Equine Herpesvirus 1 (EHV-1) and Equine Herpesvirus 4 (EHV-4) are among the important pathogenic viral factors for both domestic and feral horses. This study was carried out to determine the molecular presence of WNV, EHV-1 and EHV-4 infections in feral horses in Konya. Blood samples were taken from 36 horses selected by a randomized sampling method from a total of 250 feral horses bred together. The leukocyte samples obtained were examined virologically for the presence nucleic acid of WNV using the Nested reverse transcriptase-polymerase chain reaction assay (nested RT-PCR) method and using molecular methods for the presence of EHV-1 and EHV-4 by multiplex nested polymerase chain reaction assay (multiplex nested PCR) method. As a result, 6 (16.6%) feral horses were determined to be antigen positive for WNW, while all the horses were found to be antigen-negative for EHV-1 and EHV-4. Determining the presence of WNV infection in feral horses reveals the possibility that the sampled horses were exposed to infected birds and arthropods. Again, the failure to determine EHV-1 and EHV-4 in these horses was considered to be because these viruses could be in the latent period at the time of sampling. The presence of WNV in feral horses was revealed for the first time. It is thought that molecular characterization will also shed light on the transition of WNV between species by examining more samples.