Thanks for your query. For your information, please let me explain some of the vaccines available. There are mainly two types of vaccinations available against HPVs. Of these, Gardasil vaccine helps in protecting you against the type 6, 11, 16 and 18 of HPVs. That is four types of HPVs are covered. The next vaccine is Cervarix, which protects you from type 16 and 18 of HPV. Both Gardasil and Cervarix injections are to be taken in a six month interval period to ensure protection. Three injections are to be taken to complete the course, to ensure full protection. After getting the recommended dose of vaccines, you are protected against HPVs of the above mentioned types. Immunity lasts for about 5 years and the step is to be repeated further to get protected further. Remember, no protection will be there if you are already contracted with HPV. Vaccinating again will be of no help in such cases. If you are already contracted with it, the only method to prevent spreading is by using a condom every time you have sex. Take care.