HPV Infection (Human Papillomavirus)

Overview

Human papillomavirus (HPV) is a group of more than 100 related viruses, making it one of the most common infections worldwide. It spreads through close skin-to-skin contact, including sexual contact. Most people who are sexually active will be exposed to HPV at some point, and in the large majority the body's immune system clears the virus on its own without ever causing problems.

Different types of HPV behave differently. Some low-risk types cause common warts on the hands and feet or genital warts. Other high-risk types can cause changes in cells that, if they persist for years, may lead to cancers of the cervix, anus, throat, penis, and other areas. Vaccines and screening have made many of these cancers largely preventable.

Symptoms

Most HPV infections cause no symptoms and are never noticed. When symptoms occur, they depend on the type of virus.

• Common warts: Rough, raised bumps, usually on the hands or fingers
• Plantar warts: Hard, sometimes painful growths on the soles of the feet
• Genital warts: Soft, flesh-colored bumps in the genital or anal area

High-risk HPV usually causes no symptoms. The cell changes it can lead to are detected through screening, such as a cervical (Pap) test, long before any cancer would develop, which is why regular screening matters.

Causes

HPV infection is caused by the human papillomavirus entering the body through tiny breaks in the skin or the moist lining of the genitals, mouth, or throat. It spreads through:

• Direct skin-to-skin contact, including during vaginal, anal, and oral sex
• Touching a wart or a surface in contact with one (for common and plantar warts)
• Rarely, from a parent to a baby during birth

A person can carry and pass on the virus even without any visible warts or symptoms, which is part of why it is so widespread.

Risk Factors

• Having multiple sexual partners or a partner who has had many partners
• Beginning sexual activity at a young age
• A weakened immune system, including from HIV or immune-suppressing medicines
• Skin contact through cuts or abrasions (for warts)
• Smoking, which is linked to persistent infection and cancer risk

Diagnosis

How HPV is diagnosed depends on the situation:

• Visual examination: Warts are usually diagnosed by their appearance.
• Cervical screening: A Pap test looks for abnormal cervical cells, and an HPV test detects high-risk virus types, often from the same sample.
• Colposcopy and biopsy: If screening is abnormal, a magnified exam and tissue sample check for precancerous changes.
• Other tests: Anal or throat evaluation may be done in some people at higher risk.

There is no routine blood test that tells whether a person carries HPV overall.

Treatment

There is no medicine that cures the HPV virus itself; the body usually clears it over time. Treatment targets the problems HPV causes.

• Warts: Can be removed or treated with prescription creams, freezing (cryotherapy), or minor procedures, though they may recur.
• Precancerous cervical changes: Treated by removing or destroying the abnormal area to prevent progression to cancer.
• HPV-related cancers: Treated with surgery, radiation, chemotherapy, or a combination, depending on the type and stage.

Because HPV often clears on its own, mild abnormal screening results are sometimes simply monitored over time rather than treated right away.

Prevention

• HPV vaccination: The most effective step; it protects against the types that cause most genital warts and HPV-related cancers and works best when given before any exposure, typically in preteens.
• Cervical screening: Regular Pap and HPV tests find and allow treatment of precancerous changes early.
• Condoms and dental dams: Lower but do not eliminate the risk of transmission.
• Not smoking: Reduces the chance that an infection persists and causes harm.

When to See a Doctor

See a doctor if you notice genital warts, any new lump or growth in the genital or anal area, or unusual bleeding, especially after sex. Keep up with recommended cervical and other screenings even when you feel well, and ask about the HPV vaccine for yourself or your children, since prevention is far easier than treating the cancers HPV can cause.

Related Topics

Frequently Asked Questions

References

1. Centers for Disease Control and Prevention (CDC). Human Papillomavirus (HPV).
2. National Cancer Institute (NCI). HPV and Cancer.
3. Mayo Clinic. HPV infection.
4. MedlinePlus, U.S. National Library of Medicine. HPV.