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  • Definition

    warts are growths on the skin that occur in response to a viral infection.


    Warts come from the human papilloma virus, or from one of its 48 different subtypes, and enter the skin by direct contact. They thrive in moist environments but can occur anywhere.

    Once on the skin these viruses develop into nodules, usually gray-colored, benign protuberances that are highly contagious and easily spread by skin contact. Some warts will disappear over time if the immune system recognizes it as a virus and produces an antibody, but this is very rare. Warts are most effectively treated and removed by dermatologists.

    Warts are found in multiples, do not bleed or itch, and with the exception of the plantar wart on the foot, do not cause pain. They are most commonly found on the fingers, hands, and soles of the feet. On the hands they are pale with a roughened appearance. Skin lines tend to go around them rather than through them. On the neck and face, warts tend to be small and smooth, while the painful plantar wart found on the ball or heel of the foot has the roughened look of a callus.

    Children and teenagers are usually affected by warts because their still-developing immune system does not recognize or fight the wart virus. This changes as they age. The best precaution against plantar warts is not to go barefoot in locker rooms, poolside, or in hotels. The seemingly skimpy protection offered by wearing flip-flops or other sandals is actually all that's needed because it keeps the skin away from the wart virus.

    Types Of Warts

    Common warts have a raised, rough surface and can appear anywhere on your body but most often on your hands.

    Flat warts, smaller and smoother, appear in clusters on the backs of your hands, face or legs.

    Plantar warts appear on the plantar, or bottom surface, of your foot. They are flat, resemble calluses and are often painful.

    Filiform warts form long, finger-like profileions around your eyelids, face and neck.

    Periungual warts occur mostly in nail biters and cuticle pickers and appear under and around the fingernails.

    genital warts appear on your perineum, genitalia and anus.


    You may be prone to warts if you take a medication to suppress your immune system following a liver or kidney transplant operation or for treatment of some other disorder. Long-term steroid use also makes you susceptible.

    You can acquire warts through person-to-person contact and indirectly from such places as a public shower floor or handling money.

    Warts can spread from one area of your body to another, on adjacent fingers of an infected hand, for example. genital warts are usually transmitted by sexual contact. Usually, warts are acquired and spread through breaks in your skin.

    The incubation period (the time from initial infection until the wart appears) is about three months – but warts can lie dormant for years.


    Each person's immune system responds to warts differently, and each type of wart behaves differently.

    For some people, warts disappear on their own; these people may develop life-long immunity. Or, you may get warts that multiply rapidly and even reappear after treatment. To keep a wart from growing back after treatment, your immune system must respond to the virus and rid your body of the infection.

    Some common treatments:

    Topical medications are available in over-the-counter preparations. They contain salicylic acid that peels of infected skin.

    liquid nitrogen freezes off warts. It is effective but your doctor may need to repeat this treatment every two to four weeks.

    Electrodesiccation with curettage (scraping) surgically removes the wart. It may leave a scar. With plantar warts, especially, the scar may be as painful as the wart.

    Lasers surgically vaporize wart tissue.


    How do you know this is a wart and not a corn, callus or a mole?

    What type of treatment do you recommend?

    Which treatment is least likely to leave a scar?

    Will treatment need to be repeated?

    Does the immune system play a big role in getting rid of the virus?

    Are there any home treatments that can be used as an alternative?

    Could warts spread to the genital area from washing clothes or infected hands?

    What measures need to be taken at home to prevent spreading the virus?