Comparing One or Two Doses of the Human Papillomavirus Vaccine for the Prevention of Human Papillomavirus Infection, ESCUDDO Study

Inclusion Criteria: * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: Female * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: Aged between 12 and 16 years inclusive * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: Living in the study area without plans to move outside the country in the next six months * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: Able to communicate with study personnel * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: Willing to participate in the study and sign the informed assent * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: Supported in study participation by at least one of their parents (or guardians), who is willing to sign the informed consent document * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: In good health as determined by a medical history (physical exam will be conducted if necessary per the doctor's criterion) * INITIAL SURVEY ELIGIBILITY CRITERIA: Same as trial participants except for the age range, which is between 17 and 20 years old inclusive * END-OF-STUDY SURVEY ELIGIBILITY CRITERIA: Same as trial and initial survey participants except for the age range, which will be closely matched to the current ages of trial participants when they are attending their E54 visits, and thus is expected to be approximately between 16 and 21 years old inclusive Exclusion Criteria: * RANDOMIZED TRIAL ELIGIBILITY CRITERIA: They have a diagnosis of an autoimmune, degenerative, or neurological disease without treatment or adequate control; a progressive or severe neurological disease; a genetic immunod…