Human papillomavirus (HPV) is a common infection that causes abnormal growth of tissue on the skin of the body. There are more than 100 types of HPV, some of which cause common warts found on areas like hands and feet. However, more than 30 types are usually sexually transmitted and are known as genital HPV. Genital HPV is one of the most common sexually transmitted diseases (STDs), according to the Centers for Disease Control and Prevention (CDC).

HPV should not be confused with genital herpes, another STD. Both are caused by viruses, but HPV may cause warts while herpes may cause blisters or sores. Both diseases often do not cause any symptoms. There is no cure for either disease, but in most cases, the body’s immune system will fight off HPV. With herpes, the virus lies dormant in the body and can cause future outbreaks.

Sexually transmitted HPVs are categorized as low risk (which may cause genital warts) or high risk (which can lead to some types of cancer if untreated). Infection with certain high risk forms of HPV is a major cause of cervical cancer in women and is associated with other genital cancers in women and men (e.g., penile, anal).

Most sexually active people have been exposed to HPV at some point in their lives. The virus is transmitted by skin-to-skin contact with an infected person, usually through vaginal, oral or anal sex. Most people with HPV do not experience symptoms and do not know they are infected.

In women, HPV is usually detected during a gynecological exam with a Pap smear, a test that detects changes on the cervix. Physicians may also perform an HPV test that identifies high risk types of HPV. There are no tests for HPV available for men. Often the only indication that a man has HPV is the presence of genital warts.

In most cases, the body's immune system will successfully fight off the infection. However, there are several treatments available when HPV causes warts, such as creams, cryotherapy and electrocautery.

In June 2006, the U.S. Food and Drug Administration (FDA) approved the first HPV vaccine, which is for use in women. The vaccine offers protection against four strains of HPV: two that cause the majority of cervical cancers and two that cause most cases of genital warts. The federal Advisory Committee on Immunization Practices (ACIP) recommended the vaccine series be given to 11- and 12-year-old girls but it added that it could be started as early as 9 years old if necessary. Ideally, the vaccine should be given before females are sexually active. The recommendations also include giving the vaccine to women aged 13 to 25 years who have not been exposed to HPV because of its protective benefits. It is considered to be the best prevention method of genital HPV for females.

Practicing safer sex habits can also help prevent infection with genital HPV. Limiting the number of sexual partners and avoiding genital contact with individuals who have had multiple sex partners reduces the risk of infection. In addition, condoms provide some protection but transmission is possible from areas not covered by the condom.