Tampa Bay Equine Practice, LLC

04/12/2025

In light of the recent EHV-1 outbreak, horse owners have a lot of questions about biosecurity, EHV-1, and USEF biosecurity policies. Dr. Katie Flynn, USEF se...

19/11/2025

EQUINE HERPESVIRUS MYELOENCEPHALOPATHY (EHM) & EHV-1- FREQUENTLY ASKED QUESTIONS...

EQUINE HERPESVIRUS MYELOENCEPHALOPATHY (EHM) & EHV-1- FREQUENTLY ASKED QUESTIONS

1. How do we handle horses returning from events where they may have been exposed to EHV-1?

• These horses should be isolated from any other horses when they return to their home facility. Isolation requires housing them away from other horses, using different equipment to feed, clean and work with them than is used with non-isolated horses, and rigorous hygiene procedures for horse handlers (hand hygiene, wearing separate clothes when coming in contact with isolated horses, etc.). Please discuss this with your veterinarian.

• We strongly advise owners to call their veterinarian to discuss how long to keep the horses isolated at home. A minimum recommended isolation period is 21 days.

• These horses should have their temperature taken twice a day, as elevated temperature is typically the first and most common sign of infection. Horses with elevated re**al temperatures (greater than 101.5 F) should have a nasal swab and blood submitted by your veterinarian for EHV-1 PCR.

• If a horse develops a fever and is found to be shedding EHV-1, then the level of risk to other horses on the premises increases significantly. Affected farms should work closely with their veterinarian to manage the situation.

• The American Association of Equine Practitioners (AAEP) has an extensive set of Equine Herpesvirus (EHV) Control Guidelines that veterinarians can use as a resource.

2. What do we do if we already have a potentially exposed horse on a farm?

• The exposed horse should still be isolated, even if it may have already been in contact with other horses. Start isolation procedures to stop further exposure.

• It is very important to separate horses from different groups to accomplish this. Try to isolate the suspect horse without moving other horses from one group to another. Segregation of horse groups is the key, because this will help reduce spread if an outbreak starts.

• Check temperatures of all horses on the farm twice daily (fever spikes can be missed if you check once daily). If fevers are detected, then isolate the horse and test for EHV-1.

3. What anti-viral treatments can I use against EHM on a farm?

• If EHM is present on a farm, then the risk of other horses developing EHM at that farm is greatly increased. Stringent quarantine and biosecurity procedures must be implemented immediately.

• Treatment of horses with clinical neurological disease (EHM) is largely supportive—the use of anti-viral drugs is not known to be of value at this stage, but are often administered. Use of anti-inflammatory drugs and good nursing care with sling support if necessary is recommended.

• For horses that develop fever, test EHV-1 positive, or have been exposed to an EHM horse, anti-viral drugs may decrease the chance of developing EHM.

• Speak with your veterinarian regarding all medications and their suitability for your horse. We currently recommend Valacyclovir (Valtrex™) for prophylactic therapy at a dose of 30 mg/kg q 8 hr for two days, then 20 mg/kg q 12 hr for 1–2 weeks.

• The use of valacyclovir in horses that have already developed signs of EHM is questionable at this time. In that circumstance, the use of intravenous ganciclovir is preferable as it may have greater potency against the disease. The dose of ganciclovir is 2.5 mg/kg q 8 hr IV for one day then 2.5 mg/kg q 12 hr IV for one week.

• Administration of a zinc-containing supplements may be beneficial based on one epidemiologic study that found a decreased risk of EHM associated with owner-reported dietary zinc supplementation.

4. Is there any value to using booster vaccination against EHV-1 at this time?

• Unfortunately, there is not a licensed EHV-1 vaccination product with a label claim for prevention or control of EHM.

• EHV-1 vaccines have been shown to reduce nasal shedding and, in some cases, reduce viremia. These products may therefore have some theoretical value against EHM by reducing viremia, and certainly against spread of the virus by reducing viral shedding in the environment.

• If horses on the farm are previously vaccinated against EHV-1 then booster vaccination should quickly increase immunity, and perhaps reduce spread of EHV-1, if it is present.

• Vaccination in these circumstances is controversial, as some authorities speculate that immunity to EHV-1 may play a role in the development of EHM. While this is unproven, it remains a possibility. The use of vaccination is therefore a risk-based decision.

• Vaccination has no value as a treatment in affected horses.

Check the EDCC alerts page at https://equinediseasecc.org/alerts for updates regarding reported cases of EHM.

11/11/2025

Happy Veterans day to ALL who serve! I am grateful!

31/10/2025

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29/10/2025

Excellent!

How Jessica Gilbertie's breakthrough is revolutionizing treatment for medicine's most stubborn infections.

21/10/2025

Please get those rabies vaccines updated! Lmk if you need an appt.

10/10/2025

The words stared back at me from my phone screen. Words stated somewhat in jest, but regardless they brought a smile to my face. I’ve been working for that title my entire life.

10/10/2025

Peeps near Ocala, get those rabies prevention vaccines done!

17/09/2025

FLORIDA! We need to do better! Serious talk here. I am not kidding. If you wish to remain a client of mine, your horse MUST be vaccinated against rabies, annually. If it is not up to date on rabies vaccines, then you will not be seen for emergencies. Rabies is 100% fatal in humans once clinical signs develop. It can present as colic, It can present as behavior issues. It doesn't always present with rage. But I can promise you , a horse raging with rabies IS the very last thing on earth you want to be a part of. I will not gamble with my health bc someone doesn't "believe" in vaccinating against rabies. The vaccine is extraoridinarily effective. This is not a joke. Do NOT make me post a video of man dying from rabies. You will have nightmares. That is all.

23/08/2025

If your horse has stopped, or delayed sweating, please take this survey. It was created by a colleague of mine who researches anhidrosis. Much Thanks!! Share please ❤

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01/08/2025

31/07/2025

This is why I require all patients of Tampa Bay Equine Practice be vaccianted against Rabies annually! It is the great impersonator.

THE MORE YOU KNOW...

Did you know that humans can be exposed to Rabies WITHOUT sustaining a bite from an infected equine? This is because contact of skin or mucosa with the saliva could be enough to transmit the disease.

Rabies has many faces, but they are all deadly—once a horse shows clinical signs, the animal invariably dies within a few days as there is no treatment.

The good news is that modern vaccines are highly effective and current AAEP recommendations list rabies as one of the “core vaccines” that should be given to all equines annually to maintain immunity (read the full AAEP vaccination guidelines here: https://aaep.org/guidelines/vaccination-guidelines).

Equine rabies is a real risk for all horses, and a public health concern as well. Be sure to set up a regular vaccination schedule with your veterinarian if you haven’t already done so. Remember that strange behavior on behalf of your equine friend is always a valid reason to check in with your veterinarian!