Warts have a terrible reputation. Some people think they’re caused by frogs. A wart is even a term used to describe an obnoxious person. But instead of relying on false information and conjecture, let’s take a look at warts from a scientific perspective.

Types of Warts

There are two main types of warts. Both are caused by a virus called human papillomavirus, which is why warts are contagious.

Verruca Vulgaris

The most common wart is verruca vulgaris, which is commonly found on the fingers, the back of the hands, and the knees. When people pick at or bite them, warts can quickly spread to a person’s lip or fingers.

Verruca vulgaris can also move from person to person. Kids can spread the wart virus just like they spread colds when they come into contact with other kids. In fact, warts tend to be more common in children.

As kids get older, their bodies learn to fight off the wart virus and they develop immunity. Of course, adults who don’t build that immunity are more susceptible to warts.

Molluscum Contagiosum

Molluscum contagiosum is another kind of wart that is very common in children because it is very contagious and spread through contact. Wrestlers, for example, have been known to spread molluscum contagiosum.

These warts can appear any place on the body where contact occurs. Molluscum contagiosum can also grow in areas where skin is broken, making children with eczema particularly susceptible. In extreme cases, we may see hundreds of warts on a person after the wart virus has been spread by scratching.

How to Protect Your Skin

A wart is able to “hang on” to a person because the skin is growing at a slow rate. For example, the skin grows very slowly in the fingernails and around the knuckles, so those are easy places for a wart to attack and stay.

On the other hand, you don’t see many warts on regular skin surfaces. Skin turns over more rapidly in places like your thigh than your hands and knees.

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The goal is to get the skin growing more quickly. The analogy we use is a man in a canoe paddling upstream. The man in the canoe is the wart. If there is a waterfall behind him, he needs to paddle hard enough to move faster than the current that is trying to pull him towards the waterfall. Otherwise, he’ll go over the waterfall.

Salicylic acid, found in many over-the-counter remedies, helps exfoliate the skin and remove wart-infected skin cells. To stay with our canoe analogy, the salicylic acid speeds up the water in the stream so it becomes impossible for the man to keep up, and he eventually gets washed over the edge.

Remember, warts are contagious. See a dermatologist when you first notice warts to prevent them from spreading and to learn about your best options for treatment.