The HPV (human papillomavirus) vaccine Gardasil has just been approved for use in preventing anal cancer (Source). HPV is a sexually transmitted disease that causes genital warts and has been implicated in some cancers, including anal and cervical cancer. The majority of anal and cervical cancers are associated with HPV (Source).
HPV is common (around 50% of the US population has it) and difficult to control. HPV has a number of different strains. Some cause warts (including hand and genital warts), and some cause cancers (Source). It spreads by skin-to-skin contact, so any activity involving touching or licking genitals or anus can spread it. Barriers are useful in prevention, though not completely effective. As with all STIs, having few sexual partners is considered a preventative measure. Populations considered to be at high risk for HPV include men who have sex with men (presumably because of unprotected anal sex), people having anal sex, men who are not circumcised, and people with multiple partners (Source).
Gardasil is a three-shot series. It can’t grant immunity once a person’s been exposed to HPV, so it’s recommended for people who are not yet sexually active.
Anal cancer happens in both men and women, and is largely caused by HPV. Risk factors separate from the HPV-related ones include: smoking, having HIV, having a compromised immune system, and having anal sex (Source).
The FDA’s approval comes on the heels of a study showing that, in a high-risk population (men who have sex with men), Gardasil was shown to be 78% effective in preventing infection with the HPV strands that cause anal cancer (Source).
I think this is fabulous. More tools have definitely been needed in preventing HPV-related cancer. Anal cancer also seems to be something that’s rarely talked about, so I hope this will spur discussion. I certainly have further questions:
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