Human Papilloma Virus (Genital Warts)

What is human papilloma virus (HPV)?

HPV is a family of over 100 viruses that affect different parts of the body. Some strains of HPV cause warts on the feet, hands, and other parts of the body, while other strains are sexually transmitted and cause warts that affect skin in the genital area -- the vulva, vagina, cervix, rectum, anus, penis, or scrotum -- and in the mouth and throat. There are more than 30 strains of HPV that affect the genital area as well as the mouth and throat, and depending on the type of HPV involved, symptoms can be in the form of wart-like growths or abnormal cell changes that can be precancerous. The strains that affect the genital area or which can be transmitted to the mouth and throat during oral sex are the strains of HPV that will be discussed on this page.

When can HPV lead to cancer?

HPV is an infection which many people will contract, but only a small minority will have a lasting infection leading to cancer. This is because, in most cases, HPV (both low and high risk types) is cleared by the immune system. In a study of female college students, more than 90% of women infected with high risk HPV had cleared the infection 24 months later. The average time of infection is 4 to 20 months. Progression to pre-cancer occurs when infection with a high risk type persists over time and when normal cells in infected skin turn abnormal.

Infection with high-risk HPV types is a necessary but generally not a single or sufficient cause of HPV related cancers. Other factors which may contribute to developing cancer include smoking, nutrtional status, health of the immune system (e.g., HIV infection), and oral contraceptive use. Oral contraceptive users have a slightly increased risk of cervical cancer. This may be associated with lack of condom use when on the pill and lifetime number of partners, rather than any direct effect. There is insufficient evidence of a link to recommend discontinuation of oral contraceptive use in women with high-risk HPV infection.

Is HPV common?

In the US, HPV is considered to be the most common STI. According to the CDC, there are 14 million new HPV infections in the United States each year. About 79 milliion Americans are currently infected with HPV. HPV is so common that most sexually-active people will get at least one type of HPV at some point in the ir lives.

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How common are HPV related warts or cancers?

While HPV is very common, in most cases, the body fights off HPV and the infected cells return to normal. In cases where the body does not fight off HPV, the infection can cause warts to appear (within weeks or months of infection) or can lead to cancer (this can take years to develop).

According to the Centers for Disease Control, about 1% of sexually active adults in the US have genital warts at any given time.

Among HPV-related cancers, cervical cancer is the most common, with more than 10,000 women getting cervical cancer each year in the US. Other cancers caused by HPV are less common, but oropharyngeal cancers (cancers of the throat, base of tongue and tonsils) are on the rise. According to the Centers for Disease Control, 8,400 people get oropharyngeal cancer each year. Some of these cases are related to tobacco or alcohol use, but it is thought that 72% of these cases are now HPV-related.

Other cancers the are linked to HPV include vulvar cancer (2300 women develop this type of cancer each year), vaginal cancer (600 women each year), penile cancer (800 men each year), and anal cancer (1600 women and 900 men each year).

Each year, about 21,000 of HPV-related cancers could be prevented by getting the HPV vaccine.

How is it transmitted?

HPV is transmitted through direct skin-to-skin contact. HPV can be passed during vaginal, anal, and oral sex and through skin-to-skin genital contact or rubbing. It is also though that it may be possible to pass HPV through deep open mouth kissing. The virus does not survive long on inanimate objects, but it can be spread in the short-term if sex toys are shared between partners.

Condoms do not completely prevent infection, as they might not cover all areas infected with HPV. However, according to one study, women whose partners used condoms consistently were 70% less likely to acquire HPV than women whose partners did not use condoms.

HPV can spread whether or not warts are visible. Because genital HPV infections are often unseen, they can be transmitted by sex partners who do not know they're infected. A pregnant mother who is infected with HPV can also transmit the virus to her infant during vaginal childbirth.

What are the symptoms?

A majority of HPV infections have no signs or symptoms and so most people that are infected are completely unaware but can continue to transmit the virus to sex partner(s).

HPV can be detected when there is abnormal cell growth (dysplasia) on the female cervix, found during a Pap smear. Other types of HPV cause visible genital warts. In females, these growths may develop inside the vagina, where they are hard to detect. They can also develop on the lips of the vagina or around the anus. In males, they usually appear on the penis, but they are also found on the scrotum or around the anus. Very rarely, growths can be found in the mouth or the throat.

The growths are typically soft, moist, pink or red swellings and are usually painless but may itch. If allowed to grow, they can block the openings of the vagina, urethra, or anus and become very uncomfortable. They can be single or multiple growths or bumps, raised or flat, small or large and sometimes form a cauliflower-like shape. Depending on their location, genital warts can cause sores and bleeding.

Some symptoms and signs of oral HPV include sore throat, earaches, hoarseness, enlarged lymph nodes, pain while swallowing, and unexplained weight loss.

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How soon after exposure to HPV will symptoms appear?

Warts typically appear within 3 weeks to 6 months after sexual contact with an infected person, but they can also take years to appear. This time period makes it difficult to track the infection as it's passed from one partner to the next.

How is it diagnosed?

Genital warts are diagnosed by a visual inspection from your medical provider. They might also perform a vinegar wash to make the warts easier to see. For women, the Pap smear will also be performed to detect any changes in the cervical cells caused by HPV infection. If the Pap smear results indicate abnormal cell changes, a woman will typically will require a colposcopy (a procedure used to magnify cervical and vaginal tissue) and a biopsy (a procedure that removes tissue samples to be examined under a microscope).

Most men with HPV don't have any symptoms and so diagnosing HPV in men is difficult. Since there is no treatment for asymptomatic HPV, most men are not treated. It is possible for men to think they have no symptoms when they actually do. Sometimes a medical provider can see small warts that have gone unnoticed, particularly if they are right inside the opening of the penis.

Men and women should stop having sexual contact as soon as they know or think they have genital warts and they should seek treatment immediately.

For men or women who have had receptive anal sex, anal pap smears are a screening tool that is available from some medical providers. For oropharyngeal cancer, tests that examine the mouth and throat are used for screening. These tests can include a physical exam including a complete exam of the mouth and neck, various types of scans and xrays, and biopsies of cells or tissues.

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How is it treated?

The goal of treatments is to control the virus, but it is important to understand that the underlying HPV infection can't be cured. Like any type of viral infection, HPV stays in your body and can cause warts to appear in the future, particularly when your immune system is suppressed.

There are many ways to remove visible genital warts, depending on their size and location. A medical provider can get rid of smaller warts by freezing them off through cryotherapy, burning them off with an acidic chemical, or removing them through laser surgery. Cyrotherapy and acid treatments can be performed by medical providers at Health Services, and referrals will be given to women who need to be treated through laser surgery. All three procedures may require multiple follow-up visits or treatments. Some patients with HPV are also able to use a cream at home to help treat the warts.

In the case of cervical dysplasia, the treatment depends on the severity of the diagnosis and the risk of sexual transmission. For less serious cell changes, a repeat Pap Smear test and/or to treatment of the cervix with an antibiotic cream may be recommended. A medical provider might also recommend the removal of the affected cells with cryotherapy, laser surgery, or electrocautery.

How does the HPV Vaccine work?

There is a vaccine for HPV which protects against 4 types of HPV (types 6, 11, 16, 18) that are linked to 70% of cervical cancers and 90% of genital warts. It is not used to treat HPV. It is ideal to be vaccinated before you begin having sex, but it is not too late to get the vaccine if you have already been sexually active. The HPV vaccine is strongly recommended for people of all genders up to age 26.

To learn more about this vaccine, visit the HPV Vaccine page on our site.

How do I cope with an HPV infection?

Once you have been treated for HPV, the most important thing you can do for your health is to continue to have regular check-ups. If you have been recently diagnosed and treated, you will need more frequent exams to be sure that the warts have been removed. After a successful treatment men and women should continue to examine their genitals regularly to check for warts and to have annual physical exams to check for any new warts or growths that you can't see. Women should also receive annual Pap smear tests to identify any cervical cell changes.

As with other viral infections, you're less likely to experience genital wart recurrences if you take care of your health. This means that you want to maintain a strong immune system by eating right, getting exercise, getting enough sleep, managing your stress, and avoiding alcohol, tobacco, or other illegal drugs. Maintaining a healthy lifestyle will decrease the chances of recurrences, and in time, most people stop having any recurrences.

You can reduce your risk of transmitting HPV to a sexual partner by abstaining from sex, by finding other ways to express intimacy, by avoiding contact with any wart, and/or by using condoms and/or dental dams correctly and consistently every time you have sex. Like all safer sex methods (with the exception of abstinence) using condoms is not 100% safe -- contact with skin not covered by a condom can still transmit the virus, but condoms are still a crucial step to minimize risk for people who continue to be sexually active.

It is important to communicate with your sex partner(s) and give them information about HPV to make informed decisions about sexual activity. Telling a partner that you have HPV, or any other type of STI, can be a difficult and challenging experience. Some partners may react by needing some time to think about how this affects your relationship. Some partners may have a lot of questions, might want to get tested themselves, and might make the decision not to have sex for a while. It's completely normal to feel frustrated, depressed, angry, or guilty about having HPV -- most people diagnosed with an STI have the same concerns. But by taking care of your health, practicing safer sex, and informing yourself and your partners, you are taking all the necessary steps to minimize the risk of recurrences and transmitting the virus to others.

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Can HPV infections be dangerous?

A small number of genital HPV strains are linked to cancers of the cervix, vulva, vagina, anus, penis, and mouth and throat. The strains of HPV that cause genital warts do not seem to be directly associated with the strains that cause cancer. However, since a person can acquire multiple strains of HPV, medical providers consider any case of genital warts to be a warning of potentially cancerous conditions.

Most people recover from HPV infections with no health problems at all. It's not known why some people develop long-term recurrent HPV infections, pre-cancerous abnormal cell changes, or cervical cancer. The symptoms of most genital HPV infections go away by themselves within 6 months. Many people develop immunity - a natural protection - against different types of HPV.

If a pregnant woman has ever had HPV in the past, she might experience a rapid growth of genital warts during her pregnancy because of the change in her hormone levels. This condition must be monitored closely especially during delivery because she can transmit the virus to her infant. If necessary, the medical provider can remove the warts before the birth to avoid excessive bleeding or a cesarean section may be necessary if the warts are likely to bleed heavily.

When a person's immune system is weakened by diabetes, an organ transplant, Hodgkin's disease, HIV/AIDS, or other serious health conditions, they might experience an increase in the size and number of genital warts, and they might experience more frequent recurrences.

Links you can use

For more information about HPV, you can visit:

Planned Parenthood 

CDC’s National Center for HIV, STD and TB Prevention 

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