There are two main reasons why HPV vaccination can be continued even if the patient is already infected with HPV: First, there are many types of HPV, including high-risk types and low-risk types, which are divided into many subtypes. Therefore, patients with HPV infection are only infected with a certain type of infection, not all of them. After cervical vaccination, it can prevent several types of viral infections included in the vaccine, which can greatly reduce the chance of patients suffering from cervical cancer. Secondly, even if the type of HPV infection of the patient is the same as the type of HPV virus that the patient has been injected with. In this case, although it can not play a role in killing the virus after injection, it can further prevent the virus from being active and can further prevent the virus from tuberculosis with normal cells and the chance of lesions.