Dr. John Herning, McKinlay & Peters Equine Hospital
With the news dominated by the human Corona Virus very few people have noticed an equine virus has been slowly spreading across parts of the central and southwestern US. First identified in New Mexico April 15th, it has continued to march into Arizona, Texas, Kansas and as of June 25th Nebraska can now be added to the list as states affected by the virus, Vesicular Stomatitis. Vesicular Stomatitis or VS can infect cattle, horses, pigs and occasionally sheep/goats. Little known fact is people can also contract VS and become ill with flu like symptoms and fever.
Symptoms in horses consist of painful blisters to the tongue, lips and mouth making it difficult to eat and drink. In addition, teats can be affected on nursing mares causing associated foal problems, and blisters can also form on the coronet resulting in laminitis and sloughing of hooves in severe cases. Transmission of the disease is mostly by biting flies/midges, which is why VS is more prevalent in the warmer months. VS can also be transmitted horse to horse by direct contact with the fluids from ruptured blisters and contact with buckets, shared water sources and other equipment that has been contaminated. While a horse is suffering from VS, horses should be fed soft foods to decrease mouth discomfort and anti-inflammatory medications can reduce swelling and pain to encourage a horse to continue to eat and drink. Sometimes fluid therapy may need to be administered if the horse becomes dehydrated, and measures to protect and support their feet if laminitis is a concern. Luckily the disease is self-limiting in most cases and with this proper supportive care horses can heal and return to full health typically within two weeks. The number one way to prevent the spread is quarantine of infected horses and adequate separation and repellents to protect from fly transmission to healthy horses.
The real problem with VS is its enormous economic effect it can have on the horse, cattle and swine industry in terms of lost revenues, costs of treatment and cancellation of equestrian/show livestock events. VS clinical signs mimic Hoof and Mouth disease seen in cattle, pigs other cloven hooved animals, even deer and buffalo. Hoof and Mouth disease hasn’t been seen in the US since 1929, but the 2001 outbreak in England resulted in the destruction of 6 million cows and sheep and the cancellation of almost all equine transport and activities. For these reasons, the Federal Government’s response to control the spread of VS is swift and far reaching. This involves quarantining affected properties, cancellation of horse shows, auctions and restrictions or outright bans on some interstate transport. Canada also implements travel restrictions and bans from affected states/counties.
To control the spread of VS the importance of veterinary inspection and writing of health certificates for interstate travel becomes our first line of defense. The spread of this disease from state to state and county to county came about from the transportation of infected horses without proper veterinary inspection. VS has made its way to the Pacific Northwest as recent as 2009 affecting Montana and impacting us locally, and was as close as Colorado last year. For this reason, quarantine any new arrivals from out of state and carefully review health papers. If in doubt, have any out of state animals tested quickly by your veterinarian before further transmission can occur. When at shows practice strict biosecurity, especially avoiding contact with any animals from out of state, and practice good fly control. If planning an interstate trip, consult with your veterinarian as to any new outbreaks and if travel to this area is advised or if there are any difficulties, such as a second veterinary inspection and certificate required before returning to Idaho or Washington before getting your departure travel certificates. Hopefully, like Covid 19, we can get this all behind us as quickly as possible and return to normalcy.