August - every opening to your body is lined with squamous cells, that would include the mouth, the vagina, the penis, and the anus.... It is the same virus in males and females. The vaccine only works in presexual individuals who have never been exposed to the virus. A different vaccine is in clinical trials for people who have been exposed, and that is a decade away. The existing one has to go back through the FDA for use on boys, and was only done on girls in the initial clinical trials. This has nothing to do with boys being different or the virus being different. Boys are carriers of the same virus and the same vaccine is being tested on them.