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No wonder HPV is a hotbed of medical research right now: It’s extremely common, vaccine-preventable in many cases, and it plays a significant role in multiple kinds of cancer, including cervical cancer in women.

But for all the buzz about HPV in the scientific community, experts worry that many people are still fuzzy on details about the virus — including how it’s transmitted, who is most at risk, and how to protect yourself from infection.

“There’s so much that people don’t know or misunderstand about HPV,” says William Robinson, MD, a professor of gynecologic oncology at Tulane University in New Orleans. In the following, he and other leading experts shed some light on the most common HPV knowledge gaps.

1. Odds Are You’ve Probably Had HPV

HPV is the most common sexually transmitted infection in the United States: According to the CDC, 79 million Americans are currently infected with some form of HPV, and 14 million become newly infected each year.

“If you’ve been sexually active, you’ve got at least a 50 percent chance of having had the virus,” says Dr. Robinson. Some data suggests that more than 80 percent of sexually active women will get HPV at some point.

HPV is actually an umbrella term for more than 150 strains of related viruses, most of which are relatively harmless. About 40 of them can infect the genital areas in both men and women, and a smaller number can cause genital warts or cancer.

Most of the time, you’ll never even know you’ve had HPV, because most strains (except those that cause warts) are symptomless. And in 90 percent of cases, the immune system clears the virus naturally within two years, according to the CDC. But when HPV does not go away on its own, some HPV strains can cause a variety of types of cancer.

People living with HIV are more likely to have HPV infections that persist, raising their chances of developing an HPV-related cancer.

RELATED: HPV: The Viral Link to Cancer

2. Condoms Can’t Completely Protect You From HPV

While condoms can reduce your risk of HPV infection, they can’t eliminate it entirely.

“The virus can live in the scrotum and the hair-bearing areas of the genitals,” says Barbara Goff, MD, the director of gynecological oncology at the University of Washington in Seattle, so any foreplay that involves skin-to-skin genital contact can transmit the virus. So can oral and anal sex.

“That’s why it’s so important for young people to get vaccinated for HPV, well before they become sexually active,” says Dr. Goff.

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3. If You’re Infected, Your Current Partner May Not Be to Blame

If you learn you have HPV (this is most likely to occur after an abnormal Pap test result; most doctors don’t routinely test for HPV otherwise), don’t jump to conclusions about where you contracted the virus.

“Some patients assume that their current sexual partner gave it to them,” says Robinson. “But that’s probably not the case. The women who develop cervical cancer at age 40 probably got infected shortly after [having sex] with their first sexual partner.”

That’s because HPV can stay dormant for years before it starts causing the cell damage that can lead to cancer. HPV-triggered cancers can take years, or even decades, to develop.

4. If You’ve Had Abnormal Pap Smears, You May Be at Increased Risk for Other Cancers Caused by HPV

Most people who know about HPV associate it with cervical cancer, but the virus is increasingly implicated in other forms of cancer, including head and neck cancers as well as cancers of the vulva, vagina, anus, and penis. Evidence suggests that women who have had cervical cancer or precancerous changes (known as dysplasia) in the cervix are at a greater risk of HPV-related cancers in other areas of the body, says Goff.

These other HPV-related cancers are still fairly rare, but their numbers are on the rise. The American Cancer Society estimates that in 2017:

5,250 women and 2,950 men were diagnosed with anal cancer in the United States.

2,120 men were diagnosed with penile cancer.

6,020 women were diagnosed with vulvar cancer.

4,810 women were diagnosed with vaginal cancer.

12,820 women were diagnosed with cervical cancer.

There are no established screening guidelines for HPV-related cancers other than cervical cancer at present, but researchers are exploring how to identify people at high risk, so that their cancers can be identified and treated early.

For individuals at risk of anal cancer, the anal Pap test can be used to check for abnormal cells in the anal canal. This test is not routinely offered to heterosexual women and men, but talk to your doctor about getting one if you’re concerned about your anal cancer risk.

5. Smoking Raises Your Risk of HPV-Related Cancer

“Smoking weakens the immune system, which can allow HPV to grow more rampantly,” says Sharyn Lewin, MD, the medical director of gynecologic oncology at Holy Name Hospital in Teaneck, New Jersey. If you want to prevent a dormant HPV infection from turning into a precancerous or cancerous growth, kick your cigarette habit today.

6. The HPV Vaccine Isn’t Just for Girls

The HPV vaccine not only provides women with nearly 100 percent protection against cervical cancers caused by HPV types 16 and 18 — which cause 70 percent of cervical cancers — but it also provides direct health benefits for men, including prevention of genital warts. And though conclusive studies have yet to be done, many researchers believe that vaccination of boys will eventually reduce rates of head and neck and other cancers as well.

Gardasil 9, the HPV vaccine currently given in the United States, is approved by the FDA for use in females ages 9 to 26; males ages 9 to 21; and also for males ages 21 to 26 if they have sex with men, are transgender, or have low immune function (because of HIV, for example).

The general recommendation is for all girls and boys to be vaccinated at age 11 or 12, but the vaccine can be given as early as age 9, as well as in later years if a person did not receive the vaccine at the recommended age.

RELATED: Can Circumcision Prevent HPV Spread?

7. You Still Need Pap Smears Even if You’ve Gotten the HPV Vaccine

The HPV vaccine doesn’t protect against all possible high-risk types of HPV, nor does it protect against any strains a person was exposed to before vaccination, so Pap smears are still recommended for women who have had the HPV vaccine.

As of 2017, the only HPV vaccine available in the United States is Gardasil 9, which protects against HPV 16, 18, 31, 33, 45, 52, and 58, all of which can cause cancer, as well as types 6 and 11, which cause genital warts. Two earlier HPV vaccines, Cervarix and Gardasil, protect against fewer HPV strains.

8. The Vaccine Doesn't Treat HPV

This may seem obvious, but it bears repeating: The HPV vaccine is only preventive. It doesn’t fight the virus in people who’ve already acquired it. That’s partly why it’s approved only for people in their twenties and younger; chances are that older populations have already been exposed to the HPV strains the vaccine protects against. However, researchers are currently studying the value of vaccinating women older than 26.

There’s no treatment for the HPV virus, although it can go away on its own. Women who have abnormal Pap test results may be advised to wait and be retested in three to six months, have additional tests to further examine any abnormality, or have treatment to remove the abnormal cells.