Most will get it and never know it, and many who know they have it will never feel it. Sounds like a riddle, right? In a way, it is. It’s the mystery of HPV, or human papillomavirus, one of the most common viruses in modern times.

The facts about HPV, which has over 100 strains, can get confusing. Not all strains are dangerous, and most don’t cause serious diseases. To better understand HPV, let’s dispel of some myths surrounding it and its vaccinations.

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MYTH: HPV is an STD.

HPV is an STI, or sexually transmitted infection, not a disease. The distinction between an STI and a sexually transmitted disease (STD) is an important one. An infection occurs when a virus is present in your body, but it doesn’t become a disease until symptoms or abnormalities occur.

Many infections can exist in your body and stay dormant, never causing any symptoms or diseases. An STI is always the cause of an STD, but not every STI develops into a disease. In the case of HPV, the disease that occurs as a result of the infection is often cervical cancer, anal cancer or genital warts. Other rare cancers of the genitalia may also occur.

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MYTH: If you use condoms, you can’t get it.

If only it were the case that condoms protect against all STIs and STDs. HPV can be transmitted through skin-to-skin contact with infected genitals. That means you can get it through oral or manual sex as well as anal or vaginal sex.

The ease of transmission is perhaps why about 80 percent of all sexually active adults will contract HPV in their lifetimes, an estimate by the Centers for Disease Control and Prevention (CDC). But it’s hard to know the true prevalence of HPV because there is no approved way to test for the STI in men. Additionally, HPV can lie dormant for many years before causing health problems, so detecting the infection can be challenging.

MYTH: There is treatment for HPV.

There is no treatment for HPV, but according to the CDC, about 90 percent of HPV infections go away on their own— that is, if you’ve been told you have HPV, your immune system will likely fight it off in a couple of years. And because most cases are asymptomatic, it’s possible to contract and fight off the virus without ever knowing it. If you’ve been monogamous with a partner for a long time, it is likely that you share the same strain of HPV.

The STDs caused by HPV, on the other hand, can be treated. Genital warts can be treated with medicine, surgery or by being frozen off. To get medicine or surgery for genital warts you’ll have to see a doctor, but freezing kits are found at many pharmacies for over-the-counter home use. Cervical, vulva and anal cancers can be treated like many other cancers with surgery, radiation therapy or chemotherapy.

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MYTH: HPV vaccines protect you for life.

Getting a vaccine for HPV may be protective for up to a decade, but doctors hope it will work for longer in most people. The two types of HPV vaccines on the market are Gardasil and Cervarix, and data suggest they both work for at least 10 years. However, some vaccines need boosters from time to time, and because HPV vaccines are new, it’s too soon to know if this is the case. Only time— and further research— will tell.

Gardasil is approved for both sexes aged 9 to 26, and Cervarix is approved for females aged 10 to 25; both protect against certain strains of HPV. They are each approved for use for protection against the strains of HPV that most commonly lead to cervical cancer, genital warts and other diseases. Girls younger than 9, boys younger than 11 and pregnant women should not get either HPV vaccine.

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MYTH: HPV vaccines can cause brain damage.

Contrary to swirling rumors, there haven’t been documented cases of either HPV vaccine causing brain damage. The gossip may have started in 2012 after scientists at the University of British Columbia published two case studies of girls who died after receiving Gardasil. Autopsies, however, failed to confirm their causes of death.

It should be noted that case studies offer weak evidence as far as research goes. In randomized clinical trials, thousands of people were given both vaccines and experienced no side effects. In fact, HPV vaccines are among some of the safest in terms of side effects, according to the CDC. Certain risks, like allergic reactions or fainting, are associated with all vaccines.