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Ask the Infectious Disease Expert

How can microchip technology help equine facilities and events strengthen biosecurity against EHV-1 and other outbreaks?

By Katie Flynn, BVMS, MRCVS

Equine herpesvirus-1 (EHV-1) outbreaks, such as the 2025 cases that originated at a Texas barrel race, can cancel events across disciplines and lead to serious outcomes for horses. Effective biosecurity—especially prompt identification and isolation of sick horses—is vital.

Fever is usually the first sign of EHV-1 infection, appearing before nasal shedding. Biosecurity protocols that include isolating horses at the first detection of fever and monitoring clinical signs can help reduce transmission, lower disease risks and sustain business operations. When time is critical for effective disease control, microchips and electronic records provide greater reliability than traditional paper records or visual identification methods.

MICROCHIPS HELP MITIGATE OUTBREAKS
In an outbreak, rapid and accurate identification of infected, exposed, and at-risk horses is essential. Microchips offer a unique and tamper-proof method of identification that can be scanned instantly, minimizing the risk of misidentification and ensuring appropriate care and isolation of affected equids. State animal health authorities can utilize microchip numbers to trace infected and exposed horses, facilitating the identification of additional animals at risk.

Biothermal microchips, such as the BioThermo® Microchip from Merck Animal Health, take biosecurity one step further, combining identification and health monitoring in a single device. Their temperature-sensing function facilitates safe and efficient ongoing assessment of equine body temperature, which can serve as an early warning mechanism for horse owners, since elevated temperatures may indicate potential infectious disease. Electronic software systems via microchip scanning ensure automated and accurate logging of temperatures.

CRITICAL BIOSECURITY PRACTICES FOR EVERY EVENT
Implementing robust biosecurity protocols is essential for safeguarding horse health and business continuity. Prior to the event, organizers should require recent health certificates and evidence of vaccination (specifically, EHV-1 and influenza within the previous six months) for all participating horses. In addition, designated isolation areas should be established in advance for managing suspected infectious disease cases.
Monitoring horses daily for clinical signs or fever throughout the event is imperative, with mandatory reporting to a veterinarian of any clinical signs or fever (temperature over 101.5°F). This allows for prompt evaluation and immediate isolation of potential infectious disease cases, reducing exposure risks.

ALWAYS KEEP THESE FIVE BIOSECURITY MEASURES IN MIND:

• Limit direct contact between horses.
• Restrict human-to-horse interaction to essential personnel only.
• Avoid communal water sources.
• Do not share equipment unless it has been thoroughly cleaned and disinfected between uses.
• Monitor horses’ temperatures twice daily and immediately report readings above 101.5°F to a veterinarian.

ON THE HORIZON
Disease risks and biosecurity challenges are expected to evolve in response to increased interstate and international movement of competition horses and the expansion of event size and duration. The future of biosecurity will likely be influenced by ongoing innovations, including advanced diagnostic and surveillance systems, enhanced vaccines and immunotherapies, and sophisticated technologies and data management systems.

Events would benefit from adopting technologies for horse health monitoring, environmental surveillance, and automated alert systems that facilitate prompt implementation of biosecurity measures.

Together with these advancements and the development of comprehensive biosecurity strategies, event organizers can protect horse health, maintain business continuity, and proactively address infectious disease threats. The primary objective remains the same: only healthy horses enter each venue, maintain their health throughout, and return home safely.

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