Many horse owners become acutely aware of Equine Herpesvirus (EHV) when there’s an outbreak or a reported positive test in your local community. The reality is that EHV is a permanent part of the equine environment – not just at horse shows, but across the population. ©US Equestrian/Devyn Trethewey Virtually all horses are exposed to the EHV-1 virus at a young age, and the virus hides out (is “latent”) in most horses without causing symptoms. The virus is...

As we near the implementation date of the US Equestrian rule requiring microchips to be on file for all horses participating in endorsed competitions, you may be hearing continued buzz about why the USEF board passed this rule back in 2023. Earlier this year, a presidential modification delayed implementation of this rule from Dec. 1, 2025 to Dec. 1, 2026. (If you are one of many members who got your horse’s microchip implanted and on their record last year, we thank you for your...

©Leslie Potter/US Equestrian In the midst of the ongoing outbreak of EHV-1/EHM following the WPRA World Finals and Elite Barrel Race, US Equestrian understands that many horse owners are anxious to maintain their horses’ health and have a lot of questions about biosecurity and events. Dr. Katie Flynn, senior staff veterinarian at USEF, will be part of a webinar panel hosted by the American Association of Equine Practitioners on Nov. 25 . USEF will also be offering its own webinar...

US Equestrian has been made aware of an outbreak of Equine Herpes Virus (EHV-1) associated with barrel racing and rodeo-type events in Texas and Oklahoma. Several horses displaying neurologic signs of Equine Herpes Myeloencephalopathy (EHM) have been identified, with some horses testing positive on PCR. USEF is continuing to actively monitor the situation. As of November 21, 2025, the identified cases have been in the barrel racing/women’s professional rodeo subpopulation of horses. Any...

Have you heard about the potential threat of screwworm entering the United States? In December 2024, Mexico confirmed its first case of screwworm. Unfortunately, screwworm is spreading northward in Mexico and is now less than 700 miles away which is not far when it comes to fly movement. On May 13, 2025, the US Department of Agriculture (USDA) closed all land border crossing stations along the Mexico/US border, stopping all movement of animals from Mexico into the United States. Recently, Dr....

The United States Equestrian Federation (USEF) prioritizes the safety and well-being of horses that compete in USEF competitions. In support of this effort, USEF has established biosecurity resources and protocols to assist our members, including competition organizers (click here to access). Competition organizers are required to create their own protocols, including an equine isolation plan for competitions that have onsite stabling, to address potential virus outbreaks at USEF licensed...

Lexington, Ky. - Dr. Katie Flynn and Dr. Stephen Schumacher co-led a conversation on Biosecurity and Medications on Thursday, Jan. 23, at the 2025 US Equestrian Annual Meeting. The session, which was presented by Neogen, started with Dr. Flynn leading a conversation on the new microchip requirement that is to go into effect in December 2025. Dr. Schumacher’s presentation focused on Pharmacology, providing an overview of pharmacokinetics vs pharmacodynamics, how medications work within the...