Human Papillomavirus (HPV)
A human papillomavirus (HPV) is a papillomavirus that infects the epidermis and mucous membranes of humans. HPV can lead to cancers of the cervix, vulva, vagina, and anus in women. In men, it can lead to cancers of the anus and penis.
Approximately 130 HPV types have been identified. About 30-40 HPV types are typically transmitted through sexual contact and infect the anogenital region (HPV is estimated to be the most common sexually transmitted infection in the United States). Some sexually transmitted HPV types may cause genital warts. Persistent infection with "high-risk" HPV types may progress to precancerous lesions and invasive cancer. HPV infection is a cause of nearly all cases of cervical cancer.
HPV types 16, 18, 31, 33, 35 and 58 are "high-risk" sexually transmitted HPVs and may lead to the development of cervical intraepithelial neoplasia (CIN), vulvar intraepithelial neoplasia (VIN), penile intraepithelial neoplasia (PIN), and/or anal intraepithelial neoplasia (AIN).
Once an HPV viron invades a cell, an active infection occurs, and the virus can be transmitted. Several months to years may elapse before squamous intraepithelial lesions (SIL) develop and can be clinically detected. The time from active infection to clinically detectable disease makes it difficult for someone who has become infected to establish which partner was the source of infection.
Women who do not have regular cervical cancer screenings substantially increase their risk of developing cancer, because potentially precancerous lesions are not detected and they do not receive appropriate follow-up.
Pap smears have reduced the incidence and fatalities of cervical cancer in the developed world, but even so there were 11,000 cases and 3,900 deaths in the U.S. in 2008. Cervical cancer has substantial mortality in resource-poor areas; worldwide, there are 490,000 cases and 270,000 deaths.
HPV vaccines which prevent infection with the HPV types (16 and 18) that cause 70% of cervical cancer, may lead to significance decrease in cancer cervix cases.
When patients are screened with both HPV DNA testing and Pap testing the sensitivity reaches 100%. HPV DNA testing by real time PCR can diagnose CIN 2-3 among women older than 30 years. The sensitivity of HPV DNA testing alone was 94.6% and specificity was 94.1%.
With HPV testing, there was a 50% reduction in the number of deaths from cervical cancer compared to unscreened women.
Now in Saridar Lab, HPV DNA testing by real time PCR for HPV types 16, 18, 31, 33, 35 and 58 in Cervical Swab is routinely done and the results are ready in 48 hours.