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Recent reports of Equine Herpesvirus-1 (EHV-1) and Equine Herpesvirus-4 (EHV-4) have raised concern across the horse industry. With increased travel, shows, and winter stressors, it’s important for horse owners to understand how these viruses spread and what practical steps can help protect their horses.
Here’s a clear breakdown of what you need to know.
EHV-1 is a contagious virus commonly found in horses worldwide. Many horses are exposed early in life and can become latent carriers, meaning the virus remains dormant and may reactivate during stress, illness, or heavy travel.
EHV-4 is closely related to EHV-1 and often circulates at the same time. Both viruses spread the same way and respond to the same biosecurity measures
EHV-1 vs EHV4: Similarities and Differences in Equine Viruses
| EHV-1 | EHV-4 |
Disease/Symptoms | Respiratory disease with fever, nasal discharge, and coughing | Respiratory disease with fever, nasal discharge |
Affected Ages | All ages of horses | Primarily young horses or foals |
Risk of EHM (Neurological Disease) | High | Low |
Risk of Abortion | High, typically occurs within last four months of gestation (last trimester) | Low, isolated cases in last trimester |
During an outbreak, both EHV-1 and EHV-4 should both be taken seriously.
Fever
Respiratory disease
Abortion in pregnant mares
Neurologic disease (EHM)
Because the virus spreads quickly, early detection and strong biosecurity are essential.
Equine Herpes Myeloencephalopathy (EHM) is the neurologic form of EHV-1.Not all horses with EHV-1 develop EHM, but when they do, symptoms may include:
Hind-end weakness
Loss of coordination
Difficulty walking or standing
In severe cases, recumbency
EHM cases require immediate veterinary care.
EHV viruses are highly contagious in horses. They spread through:
Direct horse-to-horse contact
Aerosols from coughing or snorting
Shared equipment (tack, buckets, grooming tools)
Hands, clothing, and footwear
Contaminated stalls, trailers, and barn surfaces
Hauling, shows, training facilities, and barn traffic significantly increase exposure risk.
Yes, FBN® carries several equine vaccines commonly used as part of EHV prevention protocols, including Vetera® GOLD XP and Pneumabort-K® + 1b.
Staying current on vaccines that protect against EHV-1 and EHV-4 respiratory disease can help reduce viral shedding and lower the overall risk of transmission during an outbreak.
It is important to note that these vaccines do not prevent the neurologic form (EHM). Your veterinarian should guide the exact vaccination schedule.
Vetera® GOLD XP protects healthy horses 4 months and older (including pregnant mares) against EHV-1 and EHV-4 respiratory disease, plus additional core antigens.
Pneumabort-K® + 1b is used in pregnant mares and performance horses to aid in the prevention of respiratory disease and abortion caused by EHV-1.
Discuss with your veterinarian which product is appropriate for your horses based on age, pregnancy status, travel exposure, and current outbreak conditions.
At FBN, we know protecting your horses during an EHV-1/EHV-4 outbreak requires more than good management.
Minimizing viral spread is just as important as understanding symptoms. Strong biosecurity and consistent hygiene practices make a measurable difference in reducing disease spread at the barn, at events, and during travel.
To help prevent the spread of respiratory virus in horses, horse owners should:
Isolate new or returning horses for 2-3 weeks
Avoid sharing water buckets, tack, and grooming tools
Check temperatures twice daily
Disinfect trailers, stalls, wash racks, and common areas
Wear clean gloves, boots, and clothing when handling horses from different locations or exposure levels
Review vaccination schedules with their veterinarian
Because EHV-1 and EHV-4 can survive on surfaces for days, disinfecting high-touch areas and equipment is a critical part of containment.
FBN offers a range of supplies commonly used to support equine biosecurity during respiratory disease outbreaks. These products support the hygiene and prevention protocols recommended by veterinarians. They are not treatments for EHV-1.
Virkon® S Disinfectant is a broad-spectrum disinfectant proven effective against viruses, bacteria, and fungi. It’s widely used in equine health programs and is ideal for disinfecting:
Stalls
Barn aisles
Trailers
Buckets and waterers
High-contact surfaces
Shop Surface Disinfectant for EHV
Items like boot covers, gloves, and disposable protective layers help limit pathogen spread between horses and facilities, especially when managing sick horses or traveling.
Protecting your horses comes down to three pillars:
Early detection (watching temperatures and symptoms)
Biosecurity (cleaning, disinfecting, and reducing contact)
Vaccination oversight (reviewing protocols with your vet)
Outbreaks can evolve quickly, and having the right supplies on hand makes it easier to act fast and reduce risk. FBN offers vaccines, biosecurity products, and other animal health essentials shipped directly to your barn to help you stay prepared during high-risk periods.