HPV Vaccination in Adolescents: From Clinical Data to Implementation and Practice

Persistent human Papillomavirus (HPV) infections are now recognised as the leading cause of cervical cancer (CC). Approximately 100 types of human infecting HPV exist in nature and according to the samples collected from either pre-cancerous or cancerous lesions, almost ten are responsible for a good part of the CC cases. Two anti-HPV vaccines are currently registered worldwide - a tetravalent and a bivalent one - for which evidences of protecting effectiveness and safety have been delivered by controlled clinical trials and clinical practice. Consequently, and as a first step, several countries implemented HPV mass vaccination programmes for girls before the age of sexual debut. Moreover, and specifically for the bivalent vaccine, efficacy over various oncogenic types has been demonstrated in a broad population also including sexually active women that had potentially already acquired an HPV infection. The opportunity to extend the primary prevention to other cohorts of women up to the adult age through the use of the vaccine, improves the possibility to actively reduce the total number of CC cases. Based on two country examples, Italy and Belgium, different strategies for HPV vaccination of pre-adolescents, adolescents and young adults are discussed.