Warts: A-to-Z Guide from Diagnosis to Treatment to Prevention

Introduction to warts:

Contrary to well-established belief, the underside of a wart is smooth and round, and the entirety of warts is confined to the epidermis — the outermost layer of the skin. There are no ‘roots’!

Even without roots, they can be difficult to destroy.

Warts will not leaves scars, though some of the more aggressive wart therapies might.

Boy laying on grass. Does he have warts?

What are warts?

Warts are infections caused by viruses that are present everywhere, making them among the most common of all childhood skin conditions. The culprit will be one of more than 70 types of human papillomaviruses (HPV). They are spread when the virus touches a part of the skin where the outer protective layer is broken, either by minor trauma or by moisture. This happens most commonly on the fingers, elbows, knees, and the bottoms of the feet. A wart on the bottom of the foot is called a plantar wart – named for the plantar surface (sole) of the foot.

Genital warts (condylomata accuminata) should be addressed carefully in children in order to be sure there has been no sexual abuse.

Who gets warts?

Anyone can get them.

Some people get warts more easily than others. They are more common in children than in adults, partly because of their less mature immune systems and partly because they spend more time in wet-floored locker rooms and in active, close play.

Common warts occur in about 1 in 10 children. Genital warts occur in about 1 in 3 sexually active teens.

What are the symptoms?

Warts are firm or fleshy bumps that might become yellowish tan, grayish black, brown, or remain flesh-colored.

Under a magnifying glass, the roughened surface of a wart often looks like a tiny cauliflower. The little black dots sometimes seen are the ends of blood vessels that the wart has recruited to bring it food.

Plantar warts often make running, jumping, and even walking, uncomfortable. The tenderness can change posture and cause strain elsewhere in the body. A little wart can be a big problem. Sometimes filing with an emery board and/or wearing a doughnut bandage can alleviate the discomfort. The warts are usually most tender when they are growing most rapidly. Often, the pain will disappear within a few days even if nothing is done.

Are warts contagious?

Yes. They are spread when the virus touches a part of the skin where the outer protective layer is broken. Warts can spread by direct contact (from yourself or someone else) and by means of fomites.

Genital warts can spread through the birth experience, through innocent contact, or through sexual contact.

How long does it last?

Warts generally appear 1 to 6 months after the person has become infected. Most warts will eventually go away on their own, expelled by the body’s immune system. About 25 percent are gone within 3 to 6 months and 65 percent disappear within 2 years.

How are warts diagnosed?

They are usually diagnosed by careful examination. Sometimes lab confirmation is needed. Genital warts should be evaluated carefully in children in order to be sure there has been no sexual abuse.

How are warts treated?

Warts should be treated if they are spreading, unsightly, or continue to be painful.

Treatments abound, varying from as gentle and simple as taping a patch of banana peel on before bed, to as high-tech and powerful as superpulsed carbon-dioxide-laser vaporization.

The active ingredient in most over-the-counter wart remedies is salicylic acid, a natural substance found in many plants (willow bark) and most fruits. It can be applied either as a liquid or a patch (I prefer the patch). With regular application, many warts will disappear within 12 weeks. These topical treatments often work best if the surface of the wart is disrupted with warm soaks and/or an emery board before application.

Physicians use many options to treat warts (surgery, lasers, chemical cautery, electrodesiccation, lasers, and even chemotherapy), but freezing is the most common. Gentle freezing repeated every week or two — usually at least 4 times — is more effective than a single aggressive attempt to freeze. This approach is less painful and much less likely to scar. Physicians often use different chemical methods on genital warts.

Even though these techniques destroy the bulk of the wart viruses, direct destruction is only a part of the story. This can be seen by how poorly they work in people who have immune deficiencies. In the final analysis, it’s our own immune systems that are activated and engaged to eliminate the warts. Squaric acid applications are aimed specifically at triggering this immune response.

Sometimes oral medicines such as cimetidine are used.

Hypnosis has also been tried as a means of activating the immune system. When studied scientifically, hypnotic suggestion has proven to be as powerful as many conventional medical treatments at getting rid of warts. ‘Charming warts’ is particularly effective with children, and is discussed in leading medical textbooks. I’ve had success with dabbing warts with paint and letting children watch them glow under a black light! For added impact, I’ve sometimes pressed a painted wart onto a piece of filter paper to make a spot, and then burned the paper. I tell the child it will fall off in two weeks – and it does!

Mark Twain’s quaint solution, then, is consistent with the latest medical science:
Why, you take your cat and go and get in the graveyard ‘long about midnight when somebody that was wicked has been buried; and when it’s midnight a devil will come, or maybe two or three, but you can’t see ’em, you can only hear something like the wind, or maybe hear ’em talk; and when they’re taking that feller away, you heave your cat after ’em and say, ‘Devil follow corpse, cat follow devil, warts follow cat, I’m done with ye!’ That’ll fetch ANY wart.

How can warts be prevented?

Avoiding contact with warts is the best way to prevent them – particularly when there is a break in the skin.

Avoiding sucking or chewing on fingertips can prevent some warts on the hands. Wearing something on the feet in locker rooms and at the pool can prevent many plantar warts.

Related concepts:

HPV, Verrucae, Condylomata accuminata

Dr. Greene is a practicing physician, author, national and international TEDx speaker, and global health advocate. He is a graduate of Princeton University and University of California San Francisco.

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