Serological Evidence of Common Equine Viral Infections in a Semi-Isolated, Unvaccinated Population of Hucul Horses.
Authors: Bażanów Barbara, Pawęska Janusz T, Pogorzelska Aleksandra, Florek Magdalena, Frącka Agnieszka, Gębarowski Tomasz, Chwirot Wojciech, Stygar Dominika
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary: Viral Seroprevalence in Polish Hucul Horses A remote, unvaccinated herd of 20 Hucul horses in the Carpathian Mountains provided researchers with a unique opportunity to assess naturally acquired immunity to equine viruses circulating within their local Polish ecosystem. Using virus neutralisation serology and nasal swab culture, the team detected antibodies against five of eight viruses tested: equine herpesvirus-1 (60%), equine influenza A/H7N7 (65%), equine influenza A/H3N8 (60%), Usutu virus (25%), and equine rhinitis A virus (5%), whilst active viral shedding was not detected in any nasal secretions. The relatively high seroprevalence for EHV-1, both influenza subtypes, and notably USUV—an arbovirus not routinely considered in vaccination protocols—demonstrates that these pathogens circulate widely in Poland despite geographic isolation, suggesting wildlife and insect vectors play a significant epidemiological role. For practitioners managing Hucul bloodstock or working with other primitive breeds in similar regions, these findings underscore the importance of baseline serological screening to understand herd immunity status, and highlight the need for continued surveillance of arboviruses, particularly Usutu virus, which may warrant greater clinical attention in equine populations where vaccination coverage is limited or absent.
Read the full abstract on PubMed
Practical Takeaways
- •Semi-isolated, unvaccinated horse populations can serve as sentinel herds to detect endemic viral circulation; monitor your horses' health for signs of respiratory disease or neurological symptoms even in remote locations
- •Natural immunity to EHV-1, influenza, and arboviruses is present in unvaccinated populations, but vaccination protocols should still be considered based on individual herd risk and contact with other horses
- •Arboviruses like USUV are circulating in Polish ecosystems; consult with your veterinarian about vector control measures and awareness of non-vaccinal disease exposure in your region
Key Findings
- •EHV-1 antibodies detected in 60% (12/20) of unvaccinated Hucul horses with titres ranging from 1:8 to 1:64
- •EIV A/H7N7 and EIV A/H3N8 antibodies detected in 65% and 60% respectively, indicating natural exposure to both influenza subtypes
- •USUV arbovirus detected in 25% (5/20) of horses, demonstrating local circulation of this pathogen in Poland
- •Nasal swab isolation attempts were negative for all tested viruses (ERAV, EHV-1, EAV, EIV), suggesting chronic/past infections rather than active acute disease