Human Papilloma Virus (HPV)

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Human Papilloma Virus (HPV)

What Is It?

Human papilloma virus (HPV) causes common warts, the small, white, beige or brown skin growths that can appear almost anywhere on the body and on the moist mucous membranes near the mouth, anus and genitals.

There are more than 100 different types of HPV, each with its own favorite skin surface to invade. Some cause the small, painless, rough-surfaced warts found on the fingers and face. Others cause the larger, more painful and flatter plantar warts that grow on the soles of the feet. More than 25 different types of HPV can infect the skin covering the sex organs, cervix and opening of the anus. Genital HPV infections are very common; up to 80 percent of sexually active adults will get an HPV infection of the genital area at some point in their lives. In most cases, these infections do not cause symptoms, but in a small number of women, they cause changes in the cervix that can become cancerous if not treated. In addition, they cause genital warts , which affect about 1 percent of sexually active Americans. HPV is also linked to cancers of the penis, vagina, anus, vulva, and also to mouth and throat cancers. HPV subtypes 16 and 18 are the causes of most cancers. HPV types 6 and 11 cause most cases of genital warts.

Human papilloma viruses usually are spread by direct skin contact, such as shaking the hand of someone who has a wart on their finger or having unprotected sexual intercourse with someone who has a genital HPV infection. Genital HPV infections can be spread by people with no symptoms, but the risk of infection is particularly high if you have intercourse with someone who has genital warts. Less often, the viruses are carried on surfaces touched by someone who has warts, especially inside shoes that have been worn by someone with plantar warts. Once a person has been infected with an HPV, symptoms usually take three to four months to develop. However, in some cases, warts have developed as long as two years after contact with an infected person or contaminated surface.

Health experts estimate that common warts can be found on the hands of about one-fourth of all people in the United States, especially children. For some unknown reason, plantar warts are most common among teenagers and young adults.

Symptoms

It is possible to have an HPV skin or genital infection without having symptoms. When an HPV infection does cause a wart, the appearance varies slightly depending on its location:

• Common skin warts — These most often affect the hands, face, skin or scalp, and are especially common on sites of previous skin injury. They are small (about 6 millimeters or one-fourth of an inch), firm, painless, rounded growths that are whitish, pink, beige or brown. The wart surface may be smooth and pearly or rough like a cauliflower.

• Flat warts — These are flat, white, beige or brown growths that sometimes itch. They typically occur on the face, neck, chest, forearms, wrists or hands.

• Plantar warts — These are thick, painful overgrowths of skin on the soles of the feet. They are often mistaken for simple calluses.

• Genital warts — These usually appear as one to 10 pink, painless growths with a rough, cauliflower-like surface. In men, genital warts most commonly affect the tip of the penis, the opening of the urethra and the skin around the anus (especially in men who practice anal sex). In women, genital warts usually appear first at the posterior opening of the vagina and on the labia (the liplike folds of skin around the vagina).

Diagnosis

Your doctor usually can diagnose warts by examining the area. By looking at the area, your doctor also can determine what treatment may be necessary and if a biopsy should be done to look for cancer. In a biopsy, a small piece of tissue is removed and examined under a microscope.

People with plantar warts usually complain of pain on the bottom of their feet when walking. If you have possible plantar warts, your doctor will examine your foot and make sure there are no bone, joint or tendon problems that would explain the pain.

If you have possible genital warts, your doctor will ask about your sex habits, including whether you practice safe sex (because condoms may protect against HPV transmission) or engage in anal sex, which increases the risk for warts near the anus. In women with genital warts, the doctor may examine the surface of the cervix and vagina using an instrument called a colposcope. This tubelike instrument has a light and lenses to give the doctor a magnified view of the cervix and nearby vaginal skin. A biopsy of abnormal cervical tissue may be necessary to look for cervical cancer. A Pap smear will be done to look for microscopic precancer or early cancer of the cervix.

HPV infection often causes abnormalities in cervical cells which can be detected on a routine Pap smear. In this case, follow-up Pap smears or colposcopy will be recommended by your doctor based on the type of abnormality present, and your other risk factors for developing cervical cancer.

DNA tests can identify the specific types of HPV infection in cells taken from a woman's cervix. The test helps to identify women who have the types of HPV infection associated with the development of cervical cancer. Many doctors use this test in women with inconclusive or abnormal Pap smears, so that women at higher risk of developing cancer can have colposcopy and biopsies earlier, while women who do not have the worrisome types of DNA in their cervical cells can safely delay additional testing.

Expected Duration

Many warts disappear on their own, but this may take one or two years. Others last for longer periods.

Prevention

In June 2006, the FDA approved a vaccine against human papillomavirus for use in women. The currently available vaccine (several pharmaceutical companies are developing a version) targets HPV strains 6 and 11, which cause 90% of genital warts — as well as the major cervical cancer–causing strains, 16 and 18. Given as a set of three shots over six months, the vaccine will protect against only those four strains, and will not cure existing infections.

The Centers for Disease Control and Prevention (CDC) added the HPV vaccine to its official vaccination recommendations in July 2006. It proposed that all 11- and 12-year-old American girls get the shots, although girls as young as 9 could receive it if they're sexually active. For "catch-up," the CDC also recommends that girls and women ages 13–26 be vaccinated against HPV, regardless of their Pap test results.

The vaccine works best before an individual has been exposed to HPV. Early vaccination provides the greatest chance of preventing cervical cancer. Older girls and young women were included in the CDC recommendations because even if they've had some exposure to HPV, it may not be to the strains contained in the vaccine, so they'll get some protection.

More studies are needed before recommendations can be made for women older than 26 and for males. Obviously men can't get cervical cancer, but vaccinating males might curb HPV transmission and protect them from HPV-related genital and anal cancers.

There is no definite way to prevent all HPV infections. To lower your risk as much as possible, always use condoms and other barrier methods, such as dental dams for mouth-to-genital contact, for protection. If you or someone you know has a wart, avoid skin-to-skin contact with the wart.

Treatment

Over-the-counter ointments, lotions and plasters are available to treat common skin warts. Do not use them for warts on the face, genitals or anus. They should not be used by people with diabetes, poor circulation or infected warts. Over-the-counter remedies use strong chemicals to slowly destroy the wart over a period of weeks or months. For faster and more lasting treatment, your doctor may try several procedures, including:

• Removing the wart surgically

• Freezing the wart (cryosurgery)

• Cauterizing the wart using electricity

• Applying stronger surface (topical) medications

A doctor should always examine warts on the face, genitals and anus. In some cases, the doctor will prescribe a medication such as podofilox (Condylox) or imiquimod (Aldara), which you can apply to the wart yourself. In other cases, you doctor will use an office-based treatment, such as:

• Surgical removal

• Cryotherapy (freezing)

• Application of strong medications, such as acids or podophyllum (Podofin, Podocon-25), to the skin

• Interferon injections

• Laser therapy

Several office visits may be necessary to complete your treatment.

When To Call A Professional

Make an appointment with your doctor whenever you suspect that you have a wart on your face, genitals or anus. If you have a wart on another area, you can try nonprescription treatments on your own, and see the doctor only if home treatment does not work.

If you are older than 45, talk to your doctor before trying to remove a common wart with an over-the-counter remedy. Your doctor may want to test for skin cancer.

Prognosis

The outlook varies. Without treatment, about 50% of common warts disappear on their own within 6 to 12 months. Others dissolve when an over-the-counter remedy is used for several weeks or months. Of the office-based therapies, surgical removal of a wart gives the best immediate results, because the wart is cut away in one doctor's visit. Other forms of therapy require several office visits. After a wart has been removed, there is no guarantee that it will not come back, because it is difficult to be certain that HPV infection has been eliminated from the deeper layers of the infected skin. Some stubborn warts require several rounds of treatment before they go away for good.

Additional Info

National Institute of Arthritis and Musculoskeletal and Skin Diseases Information Clearinghouse National Insitutes of Health 1 AMS Circle Bethesda, MD 20892-3675 Phone: (301) 495-4484 Toll-Free: (877) 226-4267 Fax: (301) 718-6366 TTY: (301) 565-2966 http://www.niams.nih.gov/

American Social Health Association P.O. Box 13827 Research Triangle Park, NC 27709 Phone: (919) 361-8400 Fax: (919) 361-8425 http://www.ashastd.org/

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Last updated:	February 06, 2008