When I was a kid, my mom told me not to touch frogs because I would get warts. Although I did most of the things my mom told me, touching frogs was way too tempting. As a result, I must have handled thousands of the amphibians by my 10th birthday. And even though I did not get warts from frogs, I did get a couple of goose eggs on my head and a cut on my knee because I fell as I chased my slippery prey.

So if frogs don't cause warts, what does? The answer is viruses. Yep, warts are infections caused by different types of viruses. If you look closely at a wart, you will usually see tiny black dots within the top layer of skin. Those dots are not dirt, but tiny blood vessels that clotted as the virus invaded your body. In fact, the wart itself is not the virus. Instead, it's an area of calloused skin the virus creates. Think of it as the virus' home.

One of the most interesting things about wart viruses is that the body doesn't recognize the virus. As a result, the body makes no attempt to kill the invader, and the wart can hang around on your poor, defenseless fingers or toes for months or years. In most people, however, the immune system will finally snap to attention and kill the virus, thereby eliminating the wart.

So what should you do if you have a wart? There are plenty of nonprescription remedies to treat warts. Most of them work by exposing the wart to a mild acid that eats through the skin and kills the virus. Others work by freezing the skin, which also kills the virus. Some people go to dermatologists (skin doctors), who have stronger medicines that can kill the virus more quickly.

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