There are over 100 types of human papillomavirus (HPV), each one having a number to identify it, for example HPV-6, HPV-11, HPV-16 and HPV-18. Human papillomaviruses are viruses that can infect many parts of the body. Some types of HPV are sexually transmitted and can cause warts or other consequences such as cancer (e.g., cervical, penile and anal). The types of HPV that infect the anal and genital (anogenital) areas are not the same as the ones that infect other areas of the body such as the fingers, hands and face. The types which cause anogenital warts do not usually cause cancer.
The various types of HPV are often classified into low and high risk according to their association with cancer. The "low-risk" types are rarely associated with cancer. The "high-risk" types are more likely to lead to the development of cancer. Although certain types of HPV are associated with cancer, the development of HPV related cancer is considered a rare event.
Most men who have an anogenital HPV infection do not have any symptoms and most infections will go away without treatment within a couple of years. However, in some people HPV infections can persist for many years.
Some people with a HPV infection may develop anogenital warts (see below: "Does HPV cause anogenital warts?"). HPV infection is also associated with the development of cancers in men including penile and anal. The precancerous and cancerous changes that may result from HPV infection usually do not present with any noticeable symptoms, and therefore regular health check-ups are essential.
Some HPV infections, mostly HPV-6 and HPV-11, can cause anogenital warts. Anogenital warts are usually flesh-coloured, soft to the touch and may appear as tiny flat bumps, or bumps that look like cauliflowers. They are usually painless but may itch. They usually grow in more than one location and may cluster in large groups. Sometimes anogenital warts can be present but may not be visible if they are internal (i.e. inside the vagina or rectum) or if they are on the skin but are too small to be seen. Anogenital warts do not turn into cancer. If you are sexually active, you should have regular check-ups. If you think you have warts you should speak with a health care professional.
Persistent HPV infection, with high risk types, is the major cause of over 99% of cervical cancers. Infection with high-risk HPV types has also been found to be an important cause of anal cancer. HPV can also play a role in the development of cancers of the penis and oropharynx (in the throat, at the back of the mouth). Both anal and penile cancers are rare in Canada, but the rates of anal cancer are increasing. Anal cancers are found at high rates in HIV positive men and women and men who have sex with men.
HPV is estimated to be one of the most common sexually transmitted infections in Canada and around the world. Any person who is sexually active can get the virus. Studies show that approximately 75% of sexually active men and women will acquire an anogenital HPV infection at some point in their lives. Most HPV infections occur without any symptoms and go away without treatment within two years.
The types of HPV that cause anogenital warts (mostly HPV-6 and HPV-11) are spread by skin-to-skin contact, usually during vaginal, anal, or possibly oral sex with someone who has the infection. It is possible, however, to become infected with the virus without having penetrative sex if you come into contact with an infected area (skin-to-skin) in the anogenital region. HPV infection is more likely to be transmitted when warts are present, but the virus(es) can be transmitted even when there are no visible warts.
It is possible to be infected by more than one type of HPV at a time.
A recent diagnosis of anogenital warts or HPV related precancerous or cancerous lesion(s) does not necessarily mean that a partner has been unfaithful. Infection with HPV may have occurred years ago and the virus can remain in the body for weeks, years, or even a lifetime, without any sign of an infection. This makes it hard to know exactly when or from whom someone got the virus. There is no way to find out how long a particular infection has been there. Most people who have an anogenital HPV infection are not aware of it.
Currently, in Canada there is an HPV DNA test approved for women but not for men. However, it is possible to detect anogenital warts, which are the most common consequence of an HPV infection in men. Anogenital warts are diagnosed by a visual inspection during a physical exam by a health care professional. It is important to remember that just because you cannot see warts, does not mean that you do not have any. They may be small, or in a place where you cannot see them, such as inside the rectum. It is important to have regular check-ups by a health care professional.
There are currently no general screening recommendations in place for penile or anal cancer. The Pap (Papanicolaou) test can be used to screen for cell changes in the anus (precancerous and cancerous changes) in the same way it is used to detect cell changes in the cervix of woman. Researchers are still working to see if this is both an adequate and cost-effective way to screen for anal cancer. In the absence of screening recommendations or effective screening tests, it is very important to have regular check-ups and to tell your health care professional about any signs or symptoms you are having.
Although there is no cure for HPV infection, warts, lesions and precancerous and cancerous changes caused by the viruses can be managed and/or treated. No treatment guarantees that the HPV infection is no longer present in the body.
Some treatments for anogenital warts, such as cryotherapy (freezing the warts), are done in a clinic or doctor's office while other treatments, such as prescription creams, can be used at home. Repeat treatments are often necessary. Just because you can no longer see the wart does not mean the HPV infection is gone - the virus may still be present which means you could develop warts again without being re-exposed to the virus. For most people, warts will clear on their own over time.
The lesions and precancerous changes caused by high risk types of HPV can be treated if a health care provider feels that it is necessary. A large number of these infections will clear without any treatment. Only a small number of high risk persistent infections will progress to cancer. As with many other cancers, early detection is one of the key factors to successful treatment.
Discuss treatment options with a health care professional to determine which treatment choice may be best for you. People who are immunocompromised, especially those who are HIV-positive, may require special care.
If a woman has abnormalities detected on a Pap test or cervical cancer there is no need for her sex partner(s) to seek clinical assessment and treatment unless assessment is needed for HPV symptoms (i.e. anogenital warts) or other sexually transmitted infections. Similarly, if your sexual partner has a current or previous history of anogenital warts or HPV infection, there is no need to seek clinical assessment and treatment unless assessment is needed for HPV symptoms or other sexually transmitted infections.
While condoms do not eliminate the risk of HPV infection, using a condom, consistently and properly during vaginal, anal and oral sex decreases the chances of getting HPV or passing it on to your partner. You need to remember that a condom can only protect the area it covers, so it may be possible to become infected by any uncovered warts (e.g., on the scrotum). Using a condom will also help to protect you from other sexually transmitted infections and reduce the chances of unintended pregnancies.
Other ways to reduce your risk of infection include delaying sexual activity (waiting until you are older), limiting your number of sex partners and considering your partners' sexual history as this can create a risk to yourself (e.g., if they have had multiple previous partners).
There are now two HPV vaccines authorized for use in Canada: Gardasil® and Cervarix®.
Gardasil® provides protection against four HPV types: two that cause approximately 70 per cent of all cervical cancers (HPV-16, HPV-18) and two that cause approximately 90 per cent of all anogenital warts in males and females (HPV-6, HPV-11). It is approved for use in females and males aged 9 to 26.
Cervarix® provides protection against the two HPV types that cause approximately 70 per cent of all cervical cancers (HPV-16 and HPV-18). It has been approved for use in females aged 10 to 25.
For more detail on the HPV vaccine see the Human Papillomavirus (HPV) Prevention and HPV Vaccine fact sheet.
Remember, HPV infections are common. People should not be judged negatively because they have an infection that is transmitted sexually as it is not a reflection of personal character. It is important to realize that even with an HPV or another sexually transmitted infection it is still possible to lead a healthy balanced life, including a fulfilling sex life. Considering the link between HPV and cancer it is important to remember that if you have an HPV infection, it is unlikely that you will develop cancer.