This randomized phase IV trial compares intramuscular and intradermal fractional dose of bivalent HPV vaccine to fractional dose of nonavalent HPV vaccine among men and women aged 27-45 years in Seattle, Washington. Participants will have immune response assessed at baseline, 4 weeks, 6 months, and 12 months

Inclusion Criteria:

• Age 27-45 years at enrollment
• Not intending to receive the HPV vaccine series for the duration of the study participation
• Willing and able to: provide written informed consent, undergo clinical evaluation, adhere to follow-up schedule

Exclusion Criteria:

• Prior immunization with HPV-vaccine (Cervarix, Gardasil-4, Gardasil-9)
• Currently pregnant or breastfeeding
• Immunedeficiency disease/condition or cancer that causes clinically significant immunosuppression
• Known HIV infection
• Chemotherapy (current or within 12 months) or currently taking a medication that causes clinically significant immunosuppression.
• Unstable medical condition (e.g., malignant hypertension, poorly controlled diabetes)
• Known allergy to vaccine components
• Prior history of HPV-associated cancer
• Any medical condition which, in the opinion of the investigator, may compromise the subject's ability to safely complete the study.