| It depends on the type(s) of HPV (human papilloma virus) a person has.
In 2006, the U.S. Food and Drug Administration (FDA) approved a vaccine, Gardasil, that will protect against four of the 40 types of HPV that are sexually transmitted. Two of the types, 6 and 11, are the ones that cause 90 percent of the outbreaks of genital warts. The two others, 16 and 18, cause 70 percent of cases of cancer of the cervix. They are also associated with cancers of the vulva, penis, anus, or throat.
Right now, there is no clear evidence that the vaccine will protect an already infected person. Because, however, a person may be infected with one of the HPV types covered by the vaccine but not with another, the vaccine will protect against the HPV type(s) that a person does not already have.
The new vaccine does not offer protection against all the types of HPV that cause cervical cancer. So authorities urge sexually active women who become vaccinated to continue to have regular Pap tests. These tests can detect cervical cancer in its early, treatable stages.
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