Puppy warts (canine papilloma virus) can be compared to chicken pox in humans. Like chicken pox, puppy warts are typically benign. Generally, once the dog is exposed to the virus and presents with warts, the dog does not get them again. It is most common to see dogs under two years old get puppy warts because their immune systems are not as developed, but dogs of all ages are susceptible. You and your human family members cannot catch puppy warts from your dog.