Human papillomavirus (HPV) is one of the most common causes of sexually transmitted disease (STD) in this country. Experts estimate that as many as 24 million Americans are infected with HPV, and the incidence of the diseases it causes appears to be increasing. More than 60 types of HPV have been identified by scientists. Some types of the virus cause common skin warts. About one-third of the HPV types can be spread through sexual contact. Several types of HPV can lead to genital warts, the most recognizable sign of genital HPV infection. Certain other types of HPV have been closely associated with the development of cervical cancer and other genital cancers.
Like many STDs, HPV infection often does not cause visible symptoms. One study sponsored by the National Institute of Allergy and Infectious Diseases (NIAID) reported that almost half of the women infected with HPV had no obvious symptoms. Because the virus can remain latent in the skin, infected persons may not be aware of their infection and the potential risk of transmission to others and of developing complications.
