1. Can HPV infection be prevented? HPV infections of the reproductive tract almost never occur in people who have not had sex. In addition, starting HPV vaccination before having sex for the first time can reduce the risk of infection with the type of HPV included in the vaccine. Three vaccines have been approved by the FDA to prevent HPV infection: Cervarix® (bivalent vaccine), Gardasil® (quadrivalent vaccine), and Gardasil® 9 (nine-valent vaccine). All of these vaccines are effective in preventing new HPV infections, however, none are definitively effective in treating established HPV infections or diseases caused by HPV. Consistent and correct condom use among sexual partners reduces HPV transmission, but less frequent condom use does not reduce HPV transmission. However, because condoms do not cover all areas where the virus is likely to be transmitted, they are unlikely to be able to completely prevent infection. 2. Once infected with HPV, is the vaccine still useful? The effectiveness of the vaccine may be reduced or may not be effective at all. 3.What age is suitable for vaccination? It is recommended for girls aged 11-12 years old, and can be started at the age of 9 years old. The reason for this is that it is important to get the vaccine before the first sexual intercourse, which is unlikely to occur at this age. The recommended age for vaccination is up to 26 years old and can be considered even after HPV infection has already occurred, only with reduced efficacy. 4. Can both men and women be vaccinated? The bivalent vaccine (Cervarix), which targets HPV 16 and HPV 18, is used only for women to prevent cervical cancer and precervical lesions. Quadrivalent vaccine (Gardasil), for HPV types 16, 18, 6, and 11, is available for both men and women to prevent hepatocellular, cervical, vaginal, and vulvar cancers, as well as precancerous lesions of these cancers and genital warts. The nine-valent vaccine Gardasil®, which targets high-risk HPV types 16, 18, 31, 33, 45, 52, 58 and low-risk types 6 and 11, is available for both men and women. 5.How do I get the vaccination? The vaccination is administered by intramuscular injection in 3 doses over a period of 6 months. The specific injection schedule is: the 1st injection, at any time; the 2nd injection 1-2 months after the 1st injection; and the 3rd injection 6 months after the 1st injection. It can be done at the same time as other vaccinations. 6.Does the vaccination affect pregnancy? HPV vaccination is not recommended for pregnant women. If pregnancy is discovered during the vaccination process, vaccination is not a reason to terminate the pregnancy. 7.Can vaccination be given during breastfeeding? Women who are breastfeeding can also be vaccinated. 8.How long is the protection time after vaccination? The total protection time: at least 9 years for bivalent vaccine, at least 8 years for quadrivalent vaccine, and the protection time for nine-valent vaccine is not clear. 9.What are the adverse reactions to vaccination? Mild to moderate pain, edema, redness and itching may occur at the injection site, and systemic reactions such as headache, fever, nausea, dizziness, or fatigue may also occur. 10.Do I still need regular cervical cancer screening after vaccination? Since the current vaccine cannot prevent all types of HPV infection, regular screening is still necessary after vaccination.