Non-sexual HPV transmission and role of vaccination for a better future (Review).

Abstract

Human papilloma viruses (HPVs) belong to the Papillomaviridae family and are epitheliotropic infecting squamous epithelia (skin and mucosae). HPV is estimated to be the cause of 99% of cervical cancers (there is no evidence of significant genetic predisposition for cervical cancer), 90% of anal cancer, 65% vaginal cancers, 50% vulvar cancers, and 45-90% oropharyngeal cancers. The route of HPV transmission is primarily through skin-to-skin or skin-to-mucosa contact. Sexual transmission is the most documented, but there have been studies suggesting non-sexual courses. The horizontal transfer of HPV includes fomites, fingers, and mouth, skin contact (other than sexual). Self-inoculation is described in studies as a potential HPV transmission route, as it was certified in female virgins, and in children with genital warts (low-risk HPV) without a personal history of sexual abuse. Vertical transmission from mother to child is another HPV transfer course. Several studies have emphasized the possibility of infection through the amniotic fluid, or the placenta, or via contact with maternal genital mucosa during natural birth. Waterborne transmission of HPV has never been demonstrated; however, HPV DNA has been detected in water environments. Routine hygiene measures are proven to be inefficient in preventing HPV transmission, as the studies which have evaluated samples of HPV on contaminated medical equipment (after standard disinfection) have found them to be still positive. Annual costs associated with the morbidity and mortality of HPV-related diseases are estimated at approximately $4 billion. Once the HPV vaccine program in Australia was launched, many studies reported the initial effects: A decrease in the incidence of high-grade cervical abnormalities, no new genital warts cases in females under 21 years. Promoting greater understanding in the general public about the evident benefits of vaccination can create positive vaccine attitudes and scatter the myths of spurious side effects.