Traveling During an EHV-1 Outbreak

There are several things that horse owners who hope to travel and compete this summer should keep in mind to protect their horses from EHV-1.

The American Quarter Horse Journal

“This was the perfect storm of viruses,” Dr. Chris Morrow says of the equine herpesvirus-1 myeloencephalopathy outbreak.

According to Dr. Morrow, of Mobile Veterinary Practice in Amarillo, most horses are exposed to EHV-1 at some time in their life and might show little to no clinical signs of carrying the virus, such as an elevated temperature, nasal discharge through both nostrils, wobbly hind legs and urine dribbling. He also clarified that it is the present neurological strain of EHV-1 that causes a significant debilitating disease that can be fatal, especially if not treated.

To aid an exposed horse’s immune system in the fight against EHV-1, Dr. Morrow suggests that horse owners create a stress-free environment for the horse. A horse’s immune system is greatly weakened when the horse is stressed, so cutting back on training and hauling during the height of the EHV-1 outbreak will give the horse the chance to strengthen his immune system in the next several weeks. 

There are several things that horse owners who hope to travel and compete this summer should keep in mind to protect their horses, says Dr. Morrow. These include:

Before you head out to the show, revaccinate healthy horses to promote health. If you have younger horses, such as weanling and yearling halter horses or futurity prospects, these horses especially need booster vaccines to bolster their immune systems against EHV-1. Keep in mind that the vaccine does not prevent the neurological version of EHV-1, but it does decrease the virus’ effects on the horse’s body and reduces nasal shedding, which is how the virus is transmitted. 

Disinfecting stalls isn’t a bad idea, but it’s the health status of your horse that you should be working to boost. Since most horses have already been exposed to EHV-1 sometime in their lifetime and have successfully battled the virus, it’s more important to work toward a strong immune system by administering booster vaccines and immunostimulants, such as EquiStim. 

  • If your horse is stabled in a stuffy barn, use a fan to circulate stale air.
  • Most trailers have issues with ventilation, so if it’s possible, use fans in the trailer, too.
  • If you think that the show grounds might be contaminated, consider keeping your horse in the trailer or tying it to the outside of the trailer. In most cases, this might be feasible for someone stabling their horse for only one night.
  • Don’t stress your horse – stress compromises a horse’s immune system and makes it difficult for the horse to fight off viruses. 
  • If you normally share bits between multiple horses, either disinfect the bit between horses or designate personal bits for each horse.
  • And most importantly, don’t share water buckets, hoses or communal water troughs. If a hose was used to fill the bucket of a horse with EHV-1, it’s more than likely that the virus will be transferred to your horse via the hose. To avoid contamination, remove hoses from faucets and fill your buckets directly from the spigot.

If you plan on lying low until the mania of EHV-1 has calmed down, Dr. Morrow suggests several measures to take on a daily basis at home. These include:

  • Feeding on the ground will help horses clear their respiratory system. Since EHV-1 is spread through nasal shedding, feeding horses on the ground will help infection drain from the respiratory system.
  • If your horse needs to be doctored, pay for farm calls so that your horse doesn’t leave the property.
  • If your horse needs to be shod, only allow farriers onto your property that you are certain take the necessary steps to disinfect between clients.
  • Take your horse’s temperature twice a day and record the results. This should be done consistently at the same times every day for accurate records.
  • If you do have an infected horse, handle him last. The virus can live on your clothes and shoes, meaning that although humans cannot contract the virus, they can be carriers.

“Everything went right at the wrong time,” says Dr. Morrow, referring to the conditions that triggered the EHV-1 outbreak. He notes that the horses that have fared the worst, in terms of the virus, are “high performers,” meaning horses that compete at a high level and that might face higher stress levels than some of their counterparts. It’s these horses that especially need the extra help to strengthen their immune systems against EHV-1.