What Is HPV? The Complete Guide to Human Papillomavirus

Human papillomavirus (HPV) is the most common sexually transmitted infection worldwide. Over 200 types exist, approximately 40 infect the genital area, and about 14 are classified as high-risk for causing cancer. The CDC estimates that nearly every sexually active person will contract at least one HPV type during their lifetime. Most infections cause no symptoms and clear within 1 to 2 years, but persistent high-risk infections can lead to cervical, anal, oropharyngeal, penile, vaginal, and vulvar cancers.

HPV is one of those topics where the gap between medical reality and public understanding is enormous. Patients routinely tell me they have "never heard of HPV" or confuse it with herpes, HIV, or other infections. Yet this virus touches nearly every adult at some point, and the cancers it causes are among the most preventable in all of medicine — if people understand the basics.

What Is HPV, Exactly?

HPV is a group of more than 200 related viruses, each identified by a number. They infect epithelial cells — the cells that line the skin and mucous membranes. Some types infect cutaneous skin (causing common warts on hands and feet), while approximately 40 types infect the mucosal epithelium of the genital tract, anus, mouth, and throat. According to the CDC, approximately 13 million new genital HPV infections occur annually in the United States alone.

High-Risk vs Low-Risk Types

The distinction between high-risk and low-risk HPV types is the most clinically important concept to understand. Low-risk types (primarily HPV 6 and 11) cause genital warts but do not cause cancer. About 90% of genital warts are caused by these two types. High-risk types (primarily HPV 16 and 18, plus types 31, 33, 45, 52, 58, and others) cause no visible symptoms but can trigger cellular changes that lead to cancer over time. HPV 16 alone is responsible for approximately 50% of cervical cancers and the majority of HPV-related oropharyngeal cancers. If you are confused about the difference between HPV and herpes, our herpes vs HPV comparison clears up this common mix-up.

How HPV Spreads

HPV transmits through skin-to-skin contact, primarily during vaginal, anal, or oral sex. Condoms reduce transmission but do not eliminate it because HPV can infect skin areas not covered by condoms. The virus can also spread through non-penetrative genital contact. Transmission can occur even when the infected person has no visible warts or symptoms. Vertical transmission from mother to newborn is possible but uncommon. For details specific to HPV during pregnancy, see our dedicated guide.

HPV and Cancer: The Connection

Persistent infection with high-risk HPV types is the necessary cause of cervical cancer and a major cause of five other cancers. In the United States, HPV causes approximately 36,000 cancers annually: 12,000 cervical, 7,000 oropharyngeal in women, 16,000 oropharyngeal in men, plus anal, penile, vaginal, and vulvar cancers. The progression from HPV infection to cancer is slow — typically 10 to 20 years — providing ample opportunity for detection through cervical screening. For the full cancer picture, see our guide on HPV and cancer.

HPV Testing

For women, HPV testing is integrated into cervical screening through Pap smears and HPV co-testing. This is the most effective tool for detecting high-risk HPV before it causes cancer. For men, unfortunately, no FDA-approved HPV screening test exists — making prevention through vaccination even more important for males.

Prevention: The HPV Vaccine

Gardasil 9 is the only HPV vaccine available in the United States. It protects against nine HPV types (6, 11, 16, 18, 31, 33, 45, 52, 58) and is recommended for all individuals starting at age 9. Detailed guides are available for men, women, adult catch-up scheduling, and side effects.

HPV Clearance and Treatment

Approximately 90% of HPV infections clear within 2 years. Learn more about whether HPV goes away and the important distinction between clearance and cure. There is no antiviral treatment that eliminates HPV directly. Genital warts can be removed, and precancerous cervical changes can be treated, but the virus itself is addressed by the immune system.

When to Seek Medical Advice

See a healthcare provider if you notice any new bumps or growths in the genital area, if you receive abnormal Pap results, if a partner has been diagnosed with HPV, or if you have persistent sore throat, difficulty swallowing, or a neck lump (possible oral HPV signs). Confidential STD testing is available in all 50 states.

Frequently Asked Questions

How common is HPV really?

Extremely common. The CDC estimates that nearly every sexually active person will get HPV at some point. About 42 million Americans currently have HPV, and approximately 13 million new infections occur each year.

Can HPV be transmitted through kissing?

Oral HPV can potentially be transmitted through open-mouth kissing, though the primary transmission route for oral HPV is oral sex. Our guide on STI transmission through kissing covers this broader topic.

If HPV is so common, why should I worry?

Because a small percentage of infections persist and cause cancer — and those cancers are preventable through vaccination and screening. The fact that most infections are harmless does not eliminate the risk for the minority that aren't.

Can men get HPV-related cancer?

Yes. Men develop HPV-related oropharyngeal, anal, and penile cancers. Oropharyngeal cancer in men now outnumbers cervical cancer in the U.S. See our HPV vaccine for men guide.