The human papilloma virus (HPV) is the cause of both genital and non-genital warts. This is a very common family of viruses. There are actually more than 100 different strains of HPV. Of these, approximately 30 exist in the genital area and can cause genital warts (condyloma acuminata). These 30 strains can be further broken down to “high” and “low” risk strains.

High risk strains may cause changes in a Pap smear which may rarely progress to cancer. There are approximately 13 high-risk strains of HPV, of which two (16 & 18) are believed to cause about 70% of all cervical cancer. Low risk strains sometimes cause changes in a Pap smear, but do not progress to cancer. Of the low-risk strains, two (6 &11) are most likely to cause genital warts. (more…)

Types of HPV demonstrate a high degree of site specificity, with some HPV types only found on certain parts of the skin or mucous membranes. The overall prevalence of HPV in women is 22-35%. In men, the prevalence is 2-35% depending on the sexual practices of the population being studied.

HPV infection alone does not cause malignant transformation of infected tissue. Cofactors, such as tobacco use, ultraviolet radiation, pregnancy, folate deficiency, and immune suppression, have been implicated in this process. Patients receiving immunosuppressive drugs and patients with defects in cell-mediated immunity, including those infected with HIV are especially susceptible to developing HPV infections. (more…)