Warts are skin growths caused by the human papilloma virus (HPV), which enters the skin through tiny breaks or nicks. There are more than 100 different types of HPV, many of which can cause warts on different parts of the body. They may look different—pale or dark, rough or smooth, raised or flat—depending on where on the body they grow. Usually they are painless.
You might spread ordinary warts from one location to another on yourself. Warts may also sometimes spread from person to person, but how likely that is depends on the other person’s susceptibility. Genital and anal warts, transmitted through sexual contact, are highly contagious, however.
It's unlikely. Genital and ordinary warts are caused by different virus strains, which tend to prefer different types of tissue. Thus, it’s rare to find a wart on the hand containing a genital virus strain, or a wart on the genitals containing an ordinary virus strain—and unlikely that you will transfer them between those locations.
If you think you have a wart, it’s a good idea to see a doctor, just to make sure it’s not another skin condition, such as a skin cancer. Genital warts always require medical attention. So do warts on the soles of the feet (plantar warts) if they make walking uncomfortable. Other warts are harmless, and most disappear by themselves in one to two years. But they may grow and spread in the meantime—and they may also return later on.
If you want a wart removed, a dermatologist may use freezing (cryotherapy), lasers, surgery, electricity, and various caustic chemicals, which remove the skin tissue, and, in some cases, provoke the immune system to mount an attack against the virus. You’ll probably need repeated treatments, and some procedures may leave scars.
Over-the-counter salicylic acid products (such as Compound W and Duofilm) dissolve the excess skin layer and sometimes are irritating enough to provoke an immune response. Do-it-yourself freezing treatments (such as Wartner Wart Removal System and Compound W Freeze Off) are FDA-approved for home use. But they’re not cheap, and they don’t work for everyone. Never cut off a wart or treat genital or facial warts yourself.
Everything from lemon juice and garlic to baking soda and castor oil has been touted to remove warts. But it’s hard to know whether home remedies actually work, since warts tend to go away on their own. At least one older study showed that duct tape—inexpensive and noninvasive—was more effective than freezing warts. But two more-recent studies found that duct tape worked no better than a placebo.
There isn’t much you can do. But it is a good idea to wear sandals on pool decks and when in public locker rooms and showers. Using an electric razor or depilatory instead of a conventional razor helps prevent the skin nicks that can allow warts on the legs and face to spread. And don’t scratch or cut warts—that could cause a secondary bacterial infection.