If both partners were eligible and consent to enroll in this study, they will each be randomized to receive either Gardasil-9庐 or Hep-A.
Participants will be asked to visit the Research Nurses' Office 6 times over a period of 12 months.
A blood sample will be taken at the first visit.
For men: oral and聽penile swabs for HPV testing will be collected at each visit.
For women: oral and聽vaginal聽swabs for HPV testing will be collected at each visit.
Participants will be asked to completed electronic questionnaires at each visit.
At the end of the study, participants will be able to find out which vaccine they received and will be offered other vaccine.
Compensation: participants will be given between $60-$120 per visit, for a total of $1000 per couple if all study visits were completed.