Human papillomavirus (HPV) is a viral infection that is passed between people through skin-to-skin contact. There are more than 100 varieties of HPV, 40 of which are passed through sexual contact and can affect your genitals, mouth, or throat.

According to the Centers for Disease Control and Prevention (CDC), HPV is the most common sexually transmitted infection that affects both men and women. It’s so common that most sexually active people will get some variety of it at some point, even if they have few sexual partners.

Most people get HPV through direct sexual contact, such as oral sex. Because HPV is a skin-to-skin infection, intercourse isn’t required to contract the infection. In rare cases, a mother who has HPV can transmit the virus to her baby during delivery.

According to the CDC, the warts associated with most HPV infections go away on their own without any signs or symptoms. But the virus is still in an infected person’s body. As a result, that person may unknowingly pass HPV to sexual partners.

When the virus doesn’t go away on its own, it can cause serious health problems. These include genital warts and warts in the throat (known as recurrent respiratory papillomatosis). HPV can also cause cervical cancer and other cancers of the genitals, head, neck, and throat.

The types of HPV that cause warts are different from the types that cause cancer. Thus, having genital warts caused by HPV doesn’t mean that you’ll develop cancer.

Cancers caused by HPV often don’t show symptoms until the cancer is in later stages of growth. Regular screenings can help diagnose HPV-related health problems earlier. This can improve outlook and increase chances of survival.

The U.S. Food and Drug Administration (FDA) approved the first DNA test for HPV in 2014. Updated guidelines recommend that women have their first Pap test, or Pap smear, at age 21, regardless of onset of sexual activity.

After that, women 21 to 29 should have just a Pap test every three years. Regular Pap tests help to identify abnormal cells in women. These can signal cervical cancer or other HPV-related problems.

Women ages 30 to 65 should then be screened every five years with Pap and HPV tests at the same time. If you’re younger than the age of 30, your doctor or gynecologist may also request an HPV test if your Pap smear results are abnormal.

There are at least 13 strains of HPV that can lead to cancer. If you have one of these strains, your doctor may want to monitor you for cervical changes. You may need to get a Pap test more frequently.

Cervical changes that lead to cancer often take 10 or more years to develop, and HPV infections often go away on their own in one or two years without causing cancer. You may want to follow a course of watchful waiting instead of undergoing treatment for the abnormal or precancerous cells resulting from an infection.

Your doctor may also want to do follow-up testing with colposcopy. This procedure uses an instrument (a colposcope) to examine your vagina and cervix more closely to look for abnormal areas.

It’s important to note that the HPV test is only available for diagnosing HPV in women. There is currently no FDA-approved test available for diagnosing HPV in men.

If you have new warts or notice other changes after sexual activity, contact your doctor for an assessment.

Most cases of HPV go away on their own, so there is no treatment for the infection itself. Instead, your doctor will likely want to have you come in for repeat testing in six months or a year to see if the HPV infection persists and if any cell changes have developed that need further follow-up.

For HPV-related health issues like warts or cancer, treatment will be targeted to the specific issue.

To treat genital warts, contact your doctor. Note that getting rid of the physical warts doesn’t treat the virus itself, and the warts are likely to return.

Anyone who’s had sexual skin-to-skin contact is at risk for HPV infection. It’s impossible to know who will develop health problems from HPV, but people with weakened immune systems may be more at risk.

The easiest ways to prevent HPV are to use condoms and to limit the number of sexual partners you have.

In addition, the CDC recommends the HPV vaccine for boys and girls ages 11 or 12. Women and men can get vaccinated with Gardasil until age 26. People between the ages of 27 and 45 who have not been previously vaccinated for HPV are now eligible for Gardasil 9.

The vaccine is said to protect against the types of HPV known to be associated with cancer and also to prevent some types that cause warts.

To prevent health problems associated with HPV, be sure to get regular health checkups, screenings, and Pap smears.

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