There are over 100 types of human papillomavirus (HPV), they are distinguished by a number that identifies each type. Human papillomaviruses affect different parts of the body. Some types are sexually transmitted and can cause genital warts or can cause cancer such as cervical, anal, and penile cancers. Sexually transmitted HPV is not the same type of human papillomavirus that affects other parts of the body.
HPV is classified into low and high risk for cancer. Even though the high risk forms of HPV are associated with cancer, development of HPV related cancer is a rare event.
Gardasil vaccine provides protection against four types of HPV. HPV-16 and HPV-18 responsible for approximately 70% of all cervical cancers and two HPV-6 and HPV-11 which are responsible for 90% of all anogential warts. The vaccine is approved for males and females aged 9 to 26. In 2011 Gardasil was approved for use in women up to 45 years of age.