Gardasil is a vaccine designed to prevent infection with human papillomavirus (HPV) types 16, 18, 6, and 11. HPV types 16 and 18 currently cause about 70% of cervical cancer cases. Cervical cancer is the fifth leading cause of death from cancer in women worldwide and the leading cause of cancer related deaths among women in the majority of developing countries. HPV types 6 and 11 cause about 90% of genital warts cases.
Gardasil is only effective in preventing HPV infections, not in treating those already infected by HPV, and so the vaccine must be given before HPV infection occurs in order to be effective. For this reason it is recommended to administer the vaccine before adolescence and the onset of sexual activity.
Since Gardasil will not block infection with all of the HPV types that can cause cervical cancer, the vaccine should not be considered a substitute for routine pap smears.
Gardasil is given in three injections over six months. The second injection is two months after the first, and the third injection is four months after the second shot is administered.