Human papillomavirus (HPV) is a common sexually transmitted infection. At least 50 percent of people who are sexually active will have HPV at some time.

There are over 150 different types of HPV, each designated by its own number. Not every type of HPV causes warts. Many types don’t have any symptoms and will often clear up without treatment.

Some types, such as HPV-6 and HPV-11, can cause warts. Other types, such as HPV-16 and HPV-18, don’t cause warts but can cause certain cancers. The strength of your immune system can also determine whether a certain type of HPV causes warts.

Many people who develop HPV don’t experience any symptoms. This can lead you to spread the virus to others without realizing it.

Most people with HPV never have symptoms. Nine out of 10 cases clear up without treatment, often within two years. Other times, the virus persists in the body and symptoms result.

Warts are a common symptom. They can appear weeks, months, or even years after you’ve contracted the virus. The way the warts look, and where they appear on the body, are determined by the type of HPV you have. The types of warts include:

  • common warts: rough, red bumps that usually appear on elbows, fingers, and hands, and may be painful or bleed easily
  • genital warts: resemble irritated, cauliflowerlike clusters, tiny raised bumps, or flat, bruiselike lesions and may itch, buy rarely cause pain
  • flat warts: darkened areas of skin with slightly raised, flat tops that can crop up anywhere on the body
  • plantar warts: red and irritated, hard and grainy, and often appear on the bottoms of feet

The same types of HPV that cause genital warts may also cause warts in the mouth and throat. This is called oral HPV.

If you have oral HPV, symptoms may include:

  • earache
  • hoarseness
  • sore throat that won’t go away
  • pain upon swallowing
  • unexplained weight loss
  • swollen lymph nodes

HPV may also lead to certain types of cancer. HPV-related cancers affect about 18,000 women and 9,000 men each year. The types of cancers include:

  • cervical cancer
  • cancer of the vagina and vulva
  • cancer of the penis and scrotum
  • cancer of the anus
  • cancer at the back of the throat

HPV is usually caused by intimate, skin-to-skin contact. The virus is more likely to be transmitted if there is an opening in the skin, such as a cut, abrasion, or tear. These openings can be microscopic in size and can occur while someone is having sex.

You can get or transmit HPV even if you don’t have warts, but any type of wart can be contagious, if touched.

HPV can live outside of the body for very short periods of time. Although it’s possible for the virus to be contracted by touching objects that have been used during sexual activity, it’s rare.

Women may also transmit HPV to their baby during pregnancy. Although this is uncommon, it is important to discuss this with your doctor if you are planning to become pregnant.

Although HPV can affect anyone, certain people may be more at risk.

If you are, or have been, sexually active with several partners, you may be at greater risk. Being with a partner who has had sex with many people also increases your risk, even if they are your only sexual contact. Practicing safe sex can help reduce your chances of exposure.

Having a weakened immune system may also increase your risk. This can happen as a result of a number of medical conditions, including HIV and AIDS. Prescribed medications used to suppress the immune system, such as those needed after organ transplant surgery, can also increase risk.

If you have warts, your doctor may be able to make a diagnosis by examining them with a microscope. If no warts are visible, there are several tests for HPV available to women.

The tests include:

  • Pap smear, also called a Pap test, checks for precancerous or cancerous cells in the cervix and vagina
  • vinegar (acetic acid) solution test uses a vinegar solution, placed onto HPV-infected locations of the body, such as the genitals, and lightens the skin so it’s easier to see any warts.
  • DNA test identifies the DNA of the types of HPV that may cause genital cancers using cells taken from the cervix, and is usually for women over 30 years of age.

There aren’t any tests available for men at this time. There are currently no approved tests that diagnose or screen for penile, anal, or throat cancers.

Although there isn’t a cure for HPV, its symptoms are treatable.

Your doctor has several options for wart removal, including chemical cauterization, freezing, laser therapy, or medications. The treatment used will depend upon the location, amount, and size of the warts. Removing warts doesn’t remove the virus. This means that you can still spread the virus to others if you have unprotected sexual contact.

If diagnosed early, cancers caused by HPV usually respond well to treatment.

If you have HPV, regular medical check ups may be required to keep your symptoms under control. Women should receive regular Pap smear tests to check for any precancerous or cancerous cells in the cervix. Your doctor will work with you to determine the best checkup schedule for you.

If you find that your symptoms are diminishing over time, it’s still important to stay on top of your check ups. It’s also important to take precautions to avoid spreading the virus to others. Avoiding intimate contact when you have an outbreak of warts can help.

Vaccines are currently available to protect against certain types of HPV. This includes Cervarix, Gardasil, and Gardasil 9. Gardasil and Gardasil 9 both provide protection from genital warts.

It’s recommended that boys and girls get vaccinated at age 11 or 12. The vaccine is given in a series of three injections over a 6-month period. For best results, it’s important to receive all three shots.

If you didn’t get vaccinated at that age, you may still benefit from getting vaccinated up until around age 26. The vaccines are considered to be most effective if administered before you’ve been exposed to the virus or become sexually active.

Read More: What Does an HPV Diagnosis Mean for My Relationship? »