Prevention strategies against the human papillomavirus: the effectiveness of vaccination.

It has been clearly established that sexually transmitted human papillomavirus (HPV) infections are the major cause of genital warts and cervical cancer and are a contributing factor in the development of other types of anogenital cancers. There is a higher risk of HPV infection with an increasing number of sexual partners. Health education measures aimed at improving the use of condoms, reducing the number of sexual partners and promoting safer sex strategies have been employed with the goal of decreasing the transmission of HPV. Of these intervention strategies, promotion of condom use has been shown to be the most effective. More recently, prophylactic HPV vaccines have been developed with the aim of reducing the burden of HPV-related diseases such as cervical cancer. Two vaccines have been developed: Gardasil, a quadrivalent vaccine targeting HPV-6, -11, -16 and -18) and Cervarix, a bivalent vaccine which targets HPV-16 and -18. HPV-16 and -18 are most commonly associated with cervical cancer. In clinical trials, HPV vaccination has been shown to be safe, immunogenic and highly effective against type-specific HPV infection. Predictive data also indicate that the implementation of HPV vaccination within a national screening program is likely to be cost-effective relative to current clinical practice.