The Basics

The fact is who are sexually active will come in with the human papillomavirus (HPV) at one point in their lives. After all, it's the STI on earth. There are roughly 100 strains of HPV out there, but of them infect the genital area—and even fewer are considered serious. de Villiers EM, Fauquet C, Broker TR. Virology, 2004, Jul.;324(1):0042-6822.

How You Get It

You can contract HPV through vaginal, anal, or oral sex, and it can even be passed by a person who's (which is pretty common—more on that below). HPV, along with herpes, is one of the few STIs that can bypass the latex barrier of a condom and infect a person through skin-to-skin .

"If your partner is a known carrier of HPV and wears a condom, you can still catch this contagious virus," says , M.D., a gynecologist based in Santa Monica.

What's It Like?

Here’s the tough part about HPV: There are usually . At least two types of HPV (types 6 and 11) can cause genital warts (in fact, of all genital warts are caused by those strains). But for most of the nearly living with the infection, there are no signs.

For most of the nearly 80 million people living with the infection, there are no signs.

How Serious Is It?

Most of the time on its own and doesn't cause any health issues. But if you've seen a Gardasil commercial, you're probably aware of its connection to cancer. Each year HPV causes about of cancer, more in woman than in men. Cervical cancer is the one that gets the most attention, but other rarer cancers—penile, anal, vaginal—also have strong associations with HPV. For instance, about 5,010 people with anal cancer each year, and about 91 percent of those cases are caused by HPV.

One more thing: The types of HPV that cause genital warts are . So though you might not like the way they look, technically, they're less serious.

What Can I Do?

Here's the great news: HPV has a vaccine. , which protects against the strains that most commonly cause cancer or genital warts, has been available since 2006. There's also and —both of which protect against even more strains of HPV.

“HPV was not even on the radar for sexually active women and men 30 years ago," Ross says. "Now the HPV vaccine is part of the health care narrative for young girls and boys.”

It's recommended that children ages 11 to 12 get of the vaccine, whereas people who get it later (ages 15 to 26) need the whole three-dose series.

Women between the ages of 21 and 65 should get a Pap test and/or every , depending on what your doc recommends.

The number of people infected with three major STDs is at (yikes!). We're tackling common misconceptions about STIs and STDs to help #ShattertheSTIgma. Because getting tested should be NBD.

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