What is human papilloma virus (HPV)?
Human papilloma virus (HPV) is a contagious virus that is spread by skin-to-skin contact. It is the most common sexually transmitted infection in Canada.
HPV can infect the outer layer of skin and the smooth, moist linings of the mouth, the rectum, the anus and genital areas of people of all sexes and genders.
There are over 100 different types of HPV. Many of these types cause the common warts that appear on hands and feet. Other low-risk types, usually HPV 6 and 11, cause genital warts. High-risk types such as HPV 16 and 18 have been linked to cancer, particularly cancer of the cervix.
For some people, HPV may go away without treatment. For many people, though, once you have an HPV infection, the virus stays in your body for a period of time. This means it is possible to have and pass on HPV, even if you do not have any symptoms.
What are genital warts?
Genital warts can appear in different forms, sometimes weeks, months or years after being infected with HPV. There can be one or many in the genital areas or around the anus. They can be flat or raised. When the warts are raised, they may look like cauliflower. The warts can be pink, brown or the same colour as your skin.
Genital warts can disappear or reappear over time.
What can increase the risk of a person getting an HPV infection?
- Being very young at the time when they first have sexual intercourse
- Having a high number of sexual partners
- If their sexual partner has had many sexual partners
- Having a history of sexual abuse
- If they use tobacco and/or marijuana
- If their immune system is suppressed either by another condition or medications
- If they have an HIV infection
HPV is passed on by contact with the virus
HPV is passed on by skin-to-skin contact. Genital HPV infections are usually passed on by having sex with an infected person involving the mouth, throat, genital and/or anal area. HPV is the most common sexually transmitted infection. It affects up to three-quarters (75%) of sexually active people over a lifetime. Using a condom during sexual intercourse can protect some areas of the skin from HPV infection.
Once HPV is spread from partner to partner there are three ways in which the infection can present in the human body:
- Asymptomatic: a person may be infected and have no symptoms and not know they even have the infection. However, this does not stop the infected person from spreading the infection to their sexual partners.
- Genital warts: these are painless cauliflower-like growths or flesh-coloured bumps of different sizes that can grow around the genital area (e.g., the vulva, the vaginal wall, the penile or scrotal area or around the anal region). Direct skin-to-skin contact with these warts can lead to their spread from one sexual partner to another.
- Cancerous changes: after an infection with a high-risk type of HPV, the infection can change your body’s cells in the infected area from normal to abnormal. If these changes are not detected and left untreated for a long time, they can lead to the development of cancer.
Testing for HPV
Most HPV infections come and go without any symptoms. There is no routine test for HPV. It is possible to test for HPV directly, but this is not usually recommended because HPV is so common. Testing to find out the type of HPV does not give any extra information about when or how the person was infected.
The presence of genital and/or anal warts may indicate an infection, and there is treatment that is available for the management of warts.
Looking for cervical changes
In people who have a cervix, a health-care provider may use a test called a Pap smear to look for signs of problems that, if left unmonitored, could lead to cervical cancer. A Pap smear is not recommended until at least age 21 and often not until age 25 in most regions of Canada. To do a Pap smear, a health-care provider uses a small tool to collect cells from the cervix. The cells are then inspected under a microscope.
Treatment for genital warts
Once genital warts are diagnosed, the health-care provider and patient decide together which approach is best. There are a number of options for treating genital warts. Some treatments work better than others. Some treatments have risks or side effects, including causing some pain. These treatments will usually be avoided unless necessary. Which treatment is chosen will usually be based on the number, site and size of the warts. It will also be based on what the patient prefers, the cost and the side effects. Some people may choose not to have any treatment.
Genital warts can be treated with medications that are used either by the infected person or are applied by a health-care provider.
Treatments you can use yourself include the following:
- Imiquimod (Aldara), a cream that is put on the warts.
- Podofilox, a liquid put on the warts using a cotton swab.
Treatments done by a heath-care provider include the following:
- Cryotherapy: this is when liquid nitrogen is applied to the wart, usually as a spray.
- Tricholoracetic acid (TCA), which your doctor puts on the warts using a cotton swab.
- In rare cases, surgery may be needed to remove the warts.
Genital warts may go away and come back
Without treatment, genital warts may go away by themselves, or they may last for years. Even if they have been treated, genital warts may come back in time.
There are vaccines that protects against HPV
There are three vaccines on the market in Canada: Gardasil, Gardasil 9 and Cervarix.
The Gardasil vaccine provides immunity to two strains of HPV that are linked to cervical cancer (HPV 16 and 18) and two strains that are linked to genital warts (HPV 6 and 11). Gardasil 9 covers the same strains of HPV as regular Gardasil, as well as five additional strains. This is the vaccine recommended by the Canadian Pediatric Society and covered by most public vaccination programs. Both Gardasil and Gardasil 9 can be given to a person of any sex.
The Cervarix vaccine provides immunity to two strains, HPV 16 and HPV 18, and can be given to people who have a cervix.
All three vaccines are made up of small, non-infective particles of a virus that is like HPV.
It is ideal to have the vaccine before beginning sexual activity, but the vaccines are still important even if you are already sexually active. For more information, see the article on Human papillomavirus (HPV) vaccine.
Genital warts and cancer
There are many types of HPV; the type of HPV that causes genital warts is considered low-risk for cancer. However, a person can be infected by more than one type of HPV. Other types of HPV are high-risk (types 16 and 18). These can lead to cancer of the cervix; less often, they can lead to cancer of the vagina, penis or scrotum. Currently, it is impossible to test warts for all described types of HPV.
Salvadori MI; Canadian Paediatric Society, Infectious Diseases and Immunization Committee. Human papillomavirus vaccine for children and adolescents. Paediatr Child Health 2018, 23(4):262–265. Retrieved from https://cps.ca/documents/position/HPV.
