Certain types of HPV viruses, the human papilloma virus, cause common and plantar warts. Almost all people will develop a wart sometime in their life. This disease is contagious but it is not practical to isolate or protect infected patients. Warts on the hand are a cosmetic problem. They may also interfere with function. Patients who visit public swimming pools seem to be especially prone to developing plantar warts. Most patients will mount an immune response and the warts will spontaneously resolve. This however may take months or years. Avoid aggressive treatment of plantar warts that are not painful.