human papillomavirus

an icosahedral DNA virus, 55 nm in diameter, of the genus Papillomavirus, family Papovaviridae; certain types cause cutaneous and genital warts; other types are associated with severe cervical intraepithelial neoplasia and anogenital and laryngeal carcinomas. Over 70 types have been characterized on the basis of DNA relatedness. SYN: infectious papilloma virus.H. infection is the most common sexually transmitted viral disease. The interval between exposure and clinical evidence of disease ranges from 3 weeks to 8 months. A single unprotected contact with an infected person carries a 60% risk of infection. At least 80% of cervical cancers are attributable to HPV infection, and 25% of all irregularities seen on Pap smears are believed to result from the presence of the virus, which is often otherwise asymptomatic. HPV typing in women with atypical squamous cells of undetermined significance (ASCUS) on cervical Pap smear helps to identify those in whom more intensive surveillance for premalignant change is warranted. Invasive cervical cancer is associated with types 16, 18, 31, 33, and others. Some 40% of HIV-positive women develop severe cervical dysplasia caused by HPV, which in many cases proceeds to fatal cancer with an aggressiveness not commonly seen among non–HIV-positive women. External genital warts (condylomata acuminata) are usually due to HPV type 6 or 11. Women with external genital warts are not at increased risk of cervical cancer and do not need colposcopy or other special surveillance if routine Pap smears are negative. About 20–30% of HPV infections regress spontaneously. Diagnosis of HPV infection is based on visual inspection (including colposcopy with application of acetic acid to the cervix), Pap smear, and biopsy, with detection of viral DNA in tissue. Treatment options include surgical excision, cryosurgery, laser ablation, loop electrosurgical excision, and intralesional injection of interferon. External genital warts usually respond to topical treatment of podofilox gel or to imiquimod (a cytokine-inducing agent), which can be applied by the patient. Subclinical HPV infection, detectable only by Pap smear or other laboratory methods, may prove impossible to eradicate. The virus cannot be cultured, and there is no test to confirm cure.

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human papillomavirus n a double-stranded DNA virus of the genus Papillomavirus (species Human papillomavirus) that has numerous genotypes causing various human warts (as the common warts of the extremities, plantar warts, and genital warts) including some associated with the production of cervical cancer called also HPV

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(HPV)

a virus - a member of the papovavirus group - that causes warts, including genital warts. There are over 50 strains of HPV: certain strains are considered to be causative factors in the development of anal and genital cancers, especially cervical cancer, but additional factors are necessary before the cells become malignant. HPV is one of the most common sexually transmitted infections. In women the presence of HPV may be detected on colposcopic examination, although techniques using DNA amplification (see polymerase chain reaction) give more accurate results and suggest that up to 40% of a normal, apparently healthy, female population may harbour these viruses. In women with an abnormal cervical smear, the DNA test is found to be positive in a much higher percentage and is therefore a useful indicator of a high risk of developing cancer of the cervix.

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(HPV) any of a number of species of papillomaviruses that cause warts, particularly plantar and genital warts, on the skin and mucous membranes in humans. Dozens of different species and strains have been isolated, now classified in the genera Alphapapillomavirus, Betapapillomavirus, Gammapapillomavirus, and Mupapillomavirus. Viruses are transmitted by either direct or indirect contact, and some are associated with malignancies of the genital tract.