Developing a First-void Urine-based Infection Model to Study HPV-specific Antibody-virion Interaction Before and After HPV Vaccination

Candidates are eligible for inclusion in the study if they: * Are females between 18 and 45 years old (including both limits) at the time of signing the informed consent form. * Have tested positive for HPV16 DNA (single or co-infection) but have no presence of apparent anogenital lesions and are thus not referred for treatment or intervention at the time of inclusion or within the last twelve months before inclusion. * Did not receive prior vaccination with a prophylactic HPV vaccine. * Are able to understand the information brochure and what the study is about. * Are willing to give informed consent to the study team to access their medical records, including details on their HPV vaccination schedule and cervical cancer screening results (smears, HPV tests, colposcopy, biopsy). Candidates must be excluded from the study if they: * Are previously (completely or partially) vaccinated against HPV or have planned administration of another HPV vaccine during the study. * Are pregnant at the time of signing informed consent or are planning to become pregnant within the full duration of the study. Participants must use an effective method of contraception throughout the entire study. Acceptable methods include combined hormonal contraception (oral, vaginal ring, transdermal patch), progestogen-only contraception (oral, injectable, implantable), intrauterine device (IUD)/intrauterine system (IUS), condom, vasectomized male partner, or (periodic) abstinence. Lactating women may be included. * Have had full hysterectomy. * Have had any anogenital lesion treated in the last twelve months before participating in the study. * Have invasive cancer (except basocellular carcinoma) or other immunocompromising conditions as described as high-risk in the latest scientific guidelines from Sciensano. * Use immunosuppressive therapy for inflammatory bowel disease, rheumatological disorders, neuromyelitis optica, sarcoidosis, adenocarcinoma in situ, or use of local anogenital corticosteroids. * Have used any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) within 30 days preceding the first dose of study vaccine, or planning to use during the study period. * Have received immunoglobulin or blood-derived products in the three months prior to the first study vaccination (Month 0), or are expected to require immunoglobulin or blood-derived products from Month 1 until Month 7 of the study. * Receive any vaccine not foreseen in the study protocol administered in the period beginning 30 days preceding each dose of the study vaccine and ending one month (minimum 30 days) after each dose of the study vaccine. * Have known allergy or history of any reaction or hypersensitivity likely to be exacerbated by any component of the Gardasil 9 vaccine or known history of severe allergic reaction to other vaccines (e.g. anaphylaxis). * Are concurrently enrolled in another clinical study of investigational agents. * Have acute disease or contraindications for vaccination at the time of enrolment. Acute disease is defined as the presence of moderate or severe illness with or without fever. Enrolment will be deferred until the condition is resolved. All vaccines can be administered to persons with a minor illness such as diarrhea, mild upper respiratory infection with or without low-grade febrile illness, i.e. oral/axillary temperature \>37.5 °C. * Have a history or current evidence of any condition or abnormality that might confound the results of the study or is not in the best interest of the individual to participate, in the opinion of the investigator. * Are, as determined by the investigator, unlikely to adhere to the study procedures, keep appointments, or are planning to relocate from the area prior to completion of the study.