The TBA has been advised of a positive serological test result(s) for Equine Viral Arteritis (EVA) in a thoroughbred mare. Two negative EVA serological test results dated after 1st January 2025 were provided to the stallion stud prior to covering, however a further blood test obtained from the mare (also taken prior to covering) has returned a positive result.
This seropositive result indicates the presence of antibodies to EVA but does not confirm whether the mare is currently infected or has previously been exposed. The mare resides within a low-risk, UK based population. Further testing is now being undertaken to determine whether there is any evidence of active infection in the mare, to establish the risk posed to the stallion.
Biosecurity measures have been implemented for both the stallion and mare, in alignment with the HBLB International Codes of Practice; with the support of their regular attending veterinary surgeons and with the oversight of the APHA.
All breeders are reminded of the continued need for vigilance and the importance of additional EVA blood testing of mares, as per the 2025 breeding season protocols: Equine Viral Arteritis (EVA) Guidance – 2025 Breeding Season, particularly while the Artervac vaccine remains unavailable for use with stallions.
The TBA is working closely with the Veterinary Medicines Directorate (VMD) to apply for an import licence for the live vaccine, Arvac, to safeguard British-based stallions and reduce the risk to the active breeding population, in the event that Artervac supplies are not resumed as forecast by Zoetis in June 2025. The TBA held a meeting with key stakeholders yesterday to discuss these matters and will keep members updated on progress.
Read the full МОНААТHER statement supplied by Shadwell below.
Download the full statement
If you have any questions, please call the TBA office on 01638 661 321.