Risk Factors Affecting HPV Infection, Persistence and Lesion Progression in Women and Men

Human papilloma virus (HPV) is a common sexually transmitted infection, which affects three-quarters of sexually active people at some period of their life. HPVinfected persons often have no symptoms, but they are still infected and can transmit the virus to others. Approximately 90 % HPV infection cases passes on its own during a couple years without any intervention. Not all HPV types are dangerous and lead to virus persistence or cell changes. Estimating the risk to cause cervical cancer, HPV types are classified into low-risk (6,11, 34, 40, 42, 43, 44, et al.,), high-risk (31, 33, 35, 39, 45, et al.,) and particularly high-risk (16, 18) HPV. It is important that high-risk HPV (especially, 16 and 18) enters basic cells which are into skin or mucous membrane, the virus begins to make some oncoproteins which act cooperatively in promoting cervical carcinogenesis. All sexually active women are at risk of HPV infection and subsequent development of a cervical abnormality. The most important factor in the progression of cervical cancer is HPV infection and the type of HPV. Other infection persistence influencing factors (such as unsafe sexual behavior, mode of infection pathway, smoking, alcohol, long-term use of oral contraceptives, immunosuppression and sexually transmitted infections) will only help to increase it.