Would Worldwide Vaccination of Both Males and Females Against the Human Papillomavirus be a Worthy Investment?

The human papillomavirus (HPV) is the most common sexually transmitted virus, carrying a lifetime risk for women of 75%. This DNA virus causes lesions of the skin and of mucous membranes (1). HPV infection is known to predispose patients to cancers of the penis, anus, vagina, vulva, cervical, oesophagus, skin and oral pharynx, accounting for 5% of all global cancer incidences. Of these, cervical cancer is of grave importance as it makes up two-thirds of all HPV-associated cancers and is a leading cause of death from cancer in women worldwide (2-4). Fortunately, pharmaceuticals have designed a bivalent (targeting HPV subtypes 16 and 18 which account for 70% of all cervical cancer cases) and a quadrivalent vaccine (targeting HPV subtypes 16, 18, 6 and 11). They have an excellent safety profile, are highly immunogenic and confer type-specific protection against HPV infection (3, 5). Considering the epidemiological information presented above, it may seem appropriate to introduce a worldwide vaccination programme targeting both males and females. However, there are several issues that require attention before such a program is started. Firstly, some argue that limited financial reserves should not be used to prevent a problem that is not a national health burden. For example, cervical cancer accounts for only 0.6% of cancer deaths per year in the USA. By not implementing a vaccination program, the money saved could be diverted elsewhere, perhaps to improve the availability of pap smear testing for more women (6). In the UK, the cost of such a vaccination program would add £72 million (130 million CAD) to the current cervical cancer control program. Future studies need to elucidate whether or not this additional cost will lead to benefits from lower cervical cancer rates while reducing costs of screening and treatment. If this is not the case, then the vaccination program may not be an efficient use of resources (7). However this does not seem likely as one study modelling an HPV vaccination program showed that if all adolescent girls in the USA were vaccinated against high-risk HPV infection, a life expectancy gain of 2.8 days would be achieved. 1340 deaths attributed to cervical cancer, 3317 cases of cervical cancer and 112,710 cases of squamous intraepithelial lesions (a pre-malignant condition that leads to cervical cancer) could be prevented in the study population's lifetime (8). Another study showed that vaccinating females with the HPV 16/18 vaccine would reduce cervical cancer …