Yes, HPV (human papillomavirus) is a sexually transmitted infection. It is the most common STI in the world, spreading primarily through vaginal, anal, and oral sex, as well as skin-to-skin genital contact. Nearly all sexually active people will be infected at some point in their lives, usually without ever knowing it.
That said, HPV doesn’t fit the image many people have of a “typical” STD. Most infections cause no symptoms, the immune system clears the virus on its own, and transmission doesn’t always require intercourse. Understanding how HPV actually works helps explain why it’s so widespread and what you can do about it.
How HPV Spreads
HPV passes from one person to another through vaginal, anal, or oral sex. But unlike many STIs, it doesn’t require the exchange of bodily fluids. The virus lives in skin cells, so close skin-to-skin touching during sex is enough for transmission. This means areas not covered by a condom can still pass or pick up the virus.
Condoms do reduce risk significantly. Consistent condom use lowers the chance of getting cancer-causing HPV strains by roughly 60% to 77% in men, based on research published in The Journal of Infectious Diseases. That’s meaningful protection, but not complete, because the virus can infect skin around the genitals that a condom doesn’t cover.
HPV can also pass from mother to baby during childbirth, though this is uncommon. A study tracking newborns found vertical transmission occurred in about 7% of births to HPV-positive mothers, and the vast majority of those infant infections cleared on their own within about four months. Persistent infection in newborns was extremely rare.
Why Most People Never Know They Have It
HPV is unusual among STIs because it rarely announces itself. Most strains produce no visible symptoms at all. Your immune system typically fights off the virus before it causes any problems. About 90% of HPV infections clear on their own within two years, according to Johns Hopkins Medicine.
This silent nature is exactly what makes HPV so prevalent. People pass it along without realizing they’re infected, and their partners may never develop symptoms either. You can carry the virus for weeks, months, or even years before it’s detected, if it ever is.
Low-Risk vs. High-Risk Strains
There are over 100 types of HPV, but they fall into two broad categories that matter for your health.
Low-risk strains (mainly types 6 and 11) cause genital warts. These are the visible, flesh-colored bumps that most people picture when they think of HPV. Over 90% of genital wart cases trace back to these two types. Warts are uncomfortable and sometimes embarrassing, but they don’t lead to cancer.
High-risk strains (mainly types 16 and 18) can trigger changes in cells that eventually become cancer. Type 16 alone causes about half of all cervical cancers worldwide. Types 16 and 18 together account for roughly two-thirds. These same high-risk strains are also linked to cancers of the vulva, vagina, penis, anus, and throat. Globally, HPV caused an estimated 620,000 new cancers in women and 70,000 in men in 2019.
The critical thing to understand: high-risk HPV doesn’t jump straight to cancer. It causes slow, progressive cell changes over years or decades. That’s why screening catches problems early, and why most people with high-risk HPV never develop cancer at all.
Screening Options and Limitations
Screening for HPV-related problems is well established for people with a cervix but limited for everyone else. Cervical screening should start at age 21 and continue through age 65. The schedule depends on your age:
- Ages 21 to 29: a Pap test every three years
- Ages 30 to 65: a Pap test every three years, an HPV test alone every five years, or both tests together every five years
Annual screening is not recommended for people at average risk. More frequent testing leads to unnecessary procedures without improving outcomes.
For men, the picture is less straightforward. There is no approved HPV test for oral or anal samples, and routine anal cancer screening isn’t currently recommended for the general population. The virus is so common in high-risk groups that a positive test result doesn’t provide useful clinical guidance. Men typically learn they have HPV only if genital warts appear or if an HPV-related cancer is diagnosed.
How Vaccination Works
The HPV vaccine is the single most effective tool for preventing infection. It protects against the strains responsible for most HPV-related cancers and genital warts. The recommended schedule is straightforward:
- Ages 9 to 14: two doses, spaced 6 to 12 months apart
- Ages 15 to 26: three doses, given over six months
- Ages 27 to 45: vaccination can be considered on a case-by-case basis for those who weren’t vaccinated earlier
The vaccine works best when given before any exposure to HPV, which is why the CDC recommends routine vaccination at age 11 or 12. Starting as early as age 9 is an option. People who are immunocompromised, including those living with HIV, need three doses regardless of the age they start.
If you’re already past the ideal age range and were never vaccinated, getting the vaccine through age 26 still provides strong protection against strains you haven’t yet encountered. After 26, the benefit decreases because most people have already been exposed to the common types.
Why HPV Gets Treated Differently Than Other STIs
HPV is technically classified as a sexually transmitted infection, but it occupies a unique space. There’s no treatment for the virus itself. Doctors can treat the problems it causes, like warts or precancerous cell changes, but the infection clears only when your immune system eliminates it. There’s also no routine test that covers all genders equally, and no partner notification protocol. The CDC specifically notes that sex partners do not need to be tested for HPV.
This can feel confusing if you’re used to thinking of STIs as conditions you test for, treat with medication, and prevent entirely with condoms. HPV doesn’t follow that pattern. It’s incredibly common, usually harmless, and best managed through vaccination before exposure and regular screening to catch the rare cases where it causes lasting damage.