QMy yearling has broken out with warts around his mouth. These warts have become quite unsightly. How do I treat him, and will they come back? Should I quarantine him so he does not spread the warts to my other horses?

AWarts are caused by the papillomavirus, and they usually appear as blemishes on the face, mouth, or nose regions in younger horses. They appear as either single warts, or as clusters of warts that have a “cauliflower” appearance. While unsightly, they usually pose no threat to the horse’s overall health and are considered merely a cosmetic blemish. In most cases, the warts will disappear on their own in a matter of time. But it is important to remember that warts are a viral, contagious disease and that proper steps should be taken in order to prevent them from spreading from one horse to another, especially if the horse is kept in the vicinity of other horses.

Younger horses are more susceptible to warts because they have less-efficient immune systems than older horses. Their skin also is not as tough, and they have less hair to ward off the insects that can carry the papillomavirus. The good news is that once a horse has been infected, it builds up an immunity and is less susceptible to future infections. Provided the horse is in good physical condition, has a good nutrition program, is wormed regularly, and is under good management, the warts should disappear within six to nine months. Short-term, the warts will not reappear because of the immunity the horse has developed for the virus.

If a horse on a farm becomes affected with warts, it is best to keep the youngster away from other horses as much as possible. Also, as a general management practice, and especially if there is an animal on the farm that is infected with warts, do not use the same equipment such as brushes, halters, bridles, etc., on both infected and non-infected horses. While there might be no way to really isolate the infected horse, good hygiene practices will help keep the warts from spreading