“…Controls of infection from HPV, carried out in four continents by the International Agency for Research on Cancer (Lyon), have proved that the majority of the infection varies substantially from one population to another and ranges from 2% to 50% in women aged between 15 and 64. A higher percentage by 15% was found in women aged between 15 and 19 years of age but the highest percentage and incidence of infection from HPV can be found in sexually active adolescents, in fact between 50% and 80% of them catch the infection within two to three years from their first sexual relationship (Baseman & Koutsky, 2005;Louvanto, Rintala, Syrjänen, Grénman, & Syrjänen, 2011;Piana, Sotgiu, Castiglia et al, 2011;Pieralli, Fallani, Lozza et al, 2011;Vaccarella, 2010). In Italy the vaccination against HPV is offered free of charge and on an active basis to pre-adolescents when they are twelve years of age, as defined in the Agreement between the Ministry of Health and the independent regions/ provinces dated 20th December 2007, in compliance with the indications provided by the World Health Organisation and on the basis of the regulations contained in the Guidelines of several industrialized countries (Bartolozzi et al, 2007;Friedman, Kahn, & Middleman, 2006; Agreement between the Government, Regions, Independent Provinces of Trento and Bolzano concerning "Strategies for the active offer of the vaccination L. ELISA ET AL.…”