PRIMARY OBJECTIVES:~I. To evaluate one dose of nonavalent human papillomavirus (HPV) vaccination compared to no vaccination in the protection against incident HPV16/18 cervical HPV infections that persist 6-months or more in women aged 18 to 30 years who are cervical HPV16/18 deoxyribonucleic acid (DNA) negative prior to and at the time of vaccination.~II. To evaluate one dose of bivalent HPV vaccination compared to no vaccination in the protection against incident HPV16/18 cervical HPV infections that persist 6-months or more in women aged 18 to 30 years who are cervical HPV16/18 DNA negative prior to and at the time of vaccination.~SECONDARY OBJECTIVES:~I. To quantitate the benefit of one dose of HPV vaccination compared to no vaccination in the protection against incident HPV16/18 cervical HPV infections that persist 6-months or more in women aged 18 to 30 years regardless of cervical HPV DNA status at the time of vaccination.~II. To estimate the health impact of older-age single-dose HPV vaccination by modeling the number of cervical cancer cases prevented as well as the cost-effectiveness of cervical cancer prevention strategies incorporating vaccination and screening in Costa Rica.~III. To evaluate the immunogenicity (absolute levels and stability of serum antibodies) of single dose HPV vaccination in women.~IV. For each vaccine separately, to evaluate one dose of HPV vaccination compared to no vaccination in the protection against:~IVa. Any new HPV16/18 anal infection that persists 6+ months. IVb. Any new HPV16/18 oral infection that persists 6+ months. IVc. Any new carcinogenic HPV cervical, anal or oral infection detected at a single timepoint and that persists 6+ months.~IVd. Any new cervical HPV6/11 infection that persists 6+ months.~OUTLINE: Patients are randomized to 1 of 3 arms.~ARM I: Patients receive one dose of recombinant human papillomavirus nonavalent vaccine (Gardasil 9) intramuscularly (IM).~ARM II: Patients receive one dose of recombinant human papillomavirus bivalent vaccine (Cervarix) IM.~ARM III: Patients receive one dose of diphtheria toxoid/tetanus toxoid/acellular pertussis vaccine adsorbed vaccine (Adacel) IM.~After completion of study, patients are followed up at 6 and 12 months, and then every 6 months thereafter.
This phase IV trial tests whether a single dose of the human papillomavirus (HPV) vaccine works in preventing cervical cancer in young women in Costa Rica. Human papilloma viruses, called HPV, are a group of viruses that very frequently cause infection in both men and women, mainly in the genital organs. There are many types of HPV, and some can cause cancer. The World Health Organization recommends a two-dose schedule for adolescents 9-14 and three doses for individuals 15 years old or older. This study examines whether a single dose of HPV vaccine can reduce the frequency with which women between ages 18-30 become infected with HPV.