Human Papillomavirus (HPV)
Genital human papillomavirus (HPV) is the most common sexually transmitted virus. Human papillomaviruses are small, double-stranded DNA viruses that infect the epithelium. There are about 100 types of HPV and are differentiated by the genetic sequence of the outer capsid protein L1.
Most HPV infections don’t cause any symptoms, and go away on their own. But HPV is important mainly because it can cause cervical cancer in women.
Infection with low-risk, or nononcogenic types, such as types 6 and 11, can cause benign or low-grade cervical cell abnormalities, genital warts and laryngeal papillomas.
High-risk HPV types are detected in 99% of cervical cancers. Type 16 is the cause of approximately 50% of cervical cancers worldwide, and types 16 and 18 together account for about 70% of cervical cancers.
HPV is also associated with several less common types of cancer in both men and women. In addition to cervical cancer, HPV infection is also associated with anogenital cancers less common than cervical cancer, such as cancer of the vulva, vagina, penis and anus.It can
also cause genital warts and warts in the upper respiratory tract.
More than 50% of sexually active men and women are infected with HPV at sometime in their lives. There is no treatment for HPV infection, but the conditions it causes can be treated.
Infection is identified by detection of HPV DNA from clinical samples.