An Overview of HPV (Human Papillomavirus)

Understanding the Cause and Ways to Prevent It

Cervical cancer vaccine
BSIP / Getty Images

The human papillomavirus (HPV) is a viral infection spread through skin-to-skin sexual contact. HPV is a group of over 100 different viruses, with at least 30 strains known to cause different types of cancer. There is currently no cure for the virus. HPV is known to cause 96 percent of cervical cancers and up to 93 percent of anal cancers.


HPV is transmitted through vaginal, anal, or oral sex with a partner who already has the virus.

If infected, signs and symptoms may take weeks, months, or even years to appear. In some cases, symptoms may never develop.


Symptoms of HPV typically appear in the form a cauliflower-like growth called genital warts. These warts can also be flat. They can be found on the inside and the outside of the vagina or around the penis or anus. These growths may take weeks or even years to show after having sex with an infected partner.

It's important to know, however, that the lack of warts does not mean you are clear HPV. Warts may be internalized, and, in some case, there may be no physical manifestation of the disease.


One of the key tools for diagnosing HPV is the Pap smear. It is used to find abnormal cells in the cervix. which may be cancer, pre-cancer, or any number other conditions. Cells are lightly scraped off the surface and sent to a lab for evaluation.

Another test, simply called the HPV test, checks for the actual virus as opposed to changes in cells.

The test can be performed at the same time as the Pap smear, either with the same swab or different swab. the strategy, called co-testing, is the preferred method for HPV screening.


Abstaining from any type of sexual activity is the best way to prevent HPV but not very realistic for most adults.

While wearing a condom provides only limited protection against the virus, risk can be further lowered by reducing your number of sex partners.

Vaccines, meanwhile, are available to prevent HPV infection in girls and boys from as early as the age of 9 all the way up to the age of 26. Vaccine options include Gardasil, Gardasil 9, and Cervarix, each of which offers protection against different types of HPV.

Risk Factors for Cancer

While most HPV infections go away on their own without any long-lasting impact on your health, infection with high-risk forms increases the risk of cancer. Still, of the people who develop abnormal cell changes (dysplasia) as a result of high-risk HPV, only a small percentage will develop cancer even when these abnormalities are not removed.

Studies show that a person's risk of developing cervical or anal cancer depends on a variety of co-factors that add up to increase the likelihood of disease. The factors can include smoking, HIV, having many children, or a family history of cancer. Gay and bisexual men are at particularly high risk of anal cancer.

The types of HPV strain are also associated with increased risk. The strains linked to the development cervical and anal cancer are 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 69, and possibly a few others.

Types 16 and 18 are considered the most dangerous.

A Word From Verywell

While safer sex should be at the forefront of HPV prevention, serious consideration should be given to vaccinating kids and young adults to better provide a shield of protection against higher risk strains of HPV.

As with all cancers, early identification is key to treatment success. If you spot a suspicious-looking wart or lesion, see your doctor and have it looked at. Additionally, if you are at high risk for cervical or anal cancer, have your status checked with a simple Pap smear procedure.