Human papilloma virus (HPV) is a virus that is the cause of common warts of the hands and feet, as well as of lesions of the mucous membranes of the oral, anal, and genital cavities.
HPV genital infection is one of the most common sexually transmitted diseases.
Some 60 subtypes of Human papilloma virus have been identified, some of which are associated with cancerous and precancerous conditions. The virus can be transmitted through sexual contact and is frequently found in cancer of the cervix.
About one-third of the HPV types can be spread through sexual contact.
Some types of Human papilloma virus (HPV) cause common skin warts. Several types can lead to genital warts, the most recognizable sign of HPV infection. In genital warts, simultaneous infection with numerous wart subtypes is common.
Other types of HPV are associated with the development of cervical cancer.
Laboratory evidence exists that shows that there is a malignant transformation induced by HPV, especially by high-risk viral types.
Despite the strong links between HPV and cervical cancer, most HPV infections resolve spontaneously and do not cause progressive lesions. Although HPV infection is common, cancer eventually develops in only a small percentage of infected patients. Other factors almost certainly act with HPV to produce cervical cancer, including:
- Cigarette smoking
- Long-term use of oral contraceptives (more than 5 years)
- Young age at first intercourse
- Having multiple sexual partners
- Having non-HPV sexually transmitted diseases
Like many other STDs, genital warts caused by HPV often do not cause symptoms. One study sponsored by the National Institute of Allergy and Infectious Diseases (NIAID) reported that almost half of the women with HPV had no visible symptoms.
In many cases, however, small, hard spots, easily visible to the eye, develop within 3 weeks to 3 months after exposure. In women, the warts occur on the lips of the vagina, inside the vagina, or around the anus. Anogenital warts may be itchy.
Women also develop cervical warts, which are flat lesions invisible in their early stages. Cervical warts are one common cause of abnormal Pap smear tests.
Warts on the skin (face, hands, legs, feet) may be itchy or slightly tender, but are often asymptomatic.
It is important for a person who may have genital warts to see a doctor so that other types of similar-looking infections or conditions can be ruled out or treated.
Genital warts are usually diagnosed by direct visual examination. A pelvic exam is necessary to test for and diagnose cervical infection, using Pap smear or other tests. Warts on the skin (face, hand, legs, feet) are diagnosed clinically.
Common warts on the skin may be treated by freezing (cryosurgery) or salicylic acid products (Occlusal, TransVer-Sal, Duofilm, and Viranol). Recurrences are frequent and laser therapy may be effective in severe cases.
Genital warts often occur in clusters and can accumulate into large masses on genital tissues. They often reappear after treatment. Depending on factors such as their size and location, genital warts are treated in several ways:
- A doctor may recommend treatment with a chemical such as 25 percent podophyllin solution, which is applied to the affected area and washed off after several hours. Podophyllin should not be used during pregnancy because it is absorbed by the skin and may cause birth defects.
- Small warts can be removed by freezing (with liquid nitrogen) or burning (electrodesiccation). Imiquimod, a 5 percent cream that is an interferon inducer, has moderate activity in clearing external genital warts.
- Surgery is occasionally needed to remove large warts that have not responded to other treatment. Doctors at some medical centers also use laser surgery to remove genital warts.
- Cervical infection and cellular changes may require colposcopy, a painless examination during which a lighted magnifying instrument is used to view the internal reproductive organs in women.
- In some cases, it is necessary to do a biopsy of cervical tissue. This involves taking a small sample of tissue from the cervix and examining it under the microscope. Depending on the nature of the cervical lesion, cauterization, freezing (cryosurgery), laser, or surgery may be necessary.
The use of condoms may reduce transmission of genital warts.