There are more than 150 human papillomaviruses (HPV) and each one is assigned a number, which identifies the HPV type.16 The HPV is transmitted primarily person-to-person through a cut, abrasion or small tear in skin or mucous membranes. There are more than 40 HPV types that can infect the male and female genitalia. The HPV is the most common cause of sexually transmitted infections and it may be transmitted by infected persons without signs or symptoms.
When genital exposure results in infection, it may first present as a nodule or groups of nodules, which may, over time, become papillomatous or wart-like. Genital warts may be small or large, raised or flat, or shaped like a cauliflower. Following oral exposure, smooth or papillomatous (cauliflower-like) nodules may appear on the gingivae, tongue, tonsils, soft palate, pharynx, larynx and nasal mucosa.
High-risk HPV strains (HPV 16 and 18) cause cervical cancer and contribute to the development of oropharyngeal cancers, e.g., cancers of the base of the tongue, tonsils, and throat. Other HPV-related cancers may affect the vulva, vagina, penis, and anus. Cancer often takes years, even decades, to develop following exposure to the HPV and the lesions are often asymptomatic until they have reached an advanced stage.
Infection with the HPV is vaccine-preventable. There are two inactivated recombinant human papillomavirus vaccines. A bivalent vaccine (Cervarix) is approved for use in girls and young women 9-15 years of age to prevent infection associated with HPV 16 and 18. A quadrivalent vaccine (Gardasil) is approved for use in both sexes to prevent infection associated with HPV 6, 11, 16, and 18.
Various chemotherapeutic agents and surgery are available to treat visible genital warts or oropharyngeal papillomatous lesions; however, it can take many treatments or procedures over an extended period of time. Women with abnormal cervical cells must have regular follow-up testing and develop treatment strategies with their personal physician. Cervical and other HPV-associated cancers, like cancers in general, are most treatable when diagnosed early.