Preventing High-Risk HPVRecently, the U.S. Food and Drug Administration (FDA) approved an HPV vaccine that is highly effective in preventing infection with HPV types 16 and 18, two high-risk HPVs. These types of HPV cause up to 70 percent of cervical cancer cases. This vaccine also protects against types 6 and 11, which cause up to 90 percent of genital warts cases.
Comparing High-Risk HPV to Low-Risk HPVLow-risk types of HPV often cause no symptoms and may cause conditions such as genital warts, but do not cause cervical cancer. Warts can form weeks, months, or years after sexual contact with a person who has genital HPV. In women, genital warts can grow inside and around the outside of the vagina, on the vulva (the "lips" or opening to the vagina) and cervix, on the groin, and in or around the anus. In men, genital warts can grow on the penis, scrotum, thigh, groin, and in or around the anus. While very rare, genital warts can grow in the mouth or throat of a person who has had oral sex with an infected person.
The size of genital warts varies, and some may be so small that you can't see them. Genital warts can be flat and flesh-colored or look bumpy, like cauliflower. They often occur in clusters or groups, and they may cause itching, burning, and discomfort.
It's also possible that warts may never appear. In fact, most people with low-risk types of genital HPV never know they are infected, because they don't get warts or any other symptoms (see HPV Symptoms).