The HPV4 vaccine is mainly for HPV6, 16, 11, 18 and other high-risk and low-risk subtypes of human papillomavirus, and generally requires three vaccinations, one after 2 months and one after 6 months. Once after 2 months and once after 6 months, respectively. Although you have received the HPV4 vaccine, you are still at risk of HPV infection because there are many different subtypes of HPV, so you should still protect yourself by avoiding unclean sex, reducing the number of visits to public baths and spas, and not using public toilets, bath towels, and other personal items.