What is HPV?
The Human papillomavirus, or HPV, is the most common sexually transmitted infection in the world today.
HPV is highly contagious and can spread by skin-to-skin contact in the genital area (penetration is not required) or during genital, anal or oral sex. Both men and women can be infected with HPV. Approximately 75% of sexually active Canadians will have at least one HPV infection in their lifetime, with the highest rates of HPV infection occurring in young people aged 15 to 24.
There are over 100 different types of HPV, with approximately 40 types that infect the genital tract. Many low-risk HPV types will simply clear up on their own. You may not even know that you are infected. However, low-risk HPV types 6 and 11 may cause warts in the genital area, and at least 15 high-risk HPV types may cause cancer.
In women, HPV has been linked to cancer of the cervix, vulva, and vagina and in men, to cancer of the penis. In both women and men, it has been linked to cancer of the anus, and mouth and throat.
Anyone who is sexually active is at risk for HPV. Since the infection often has no signs or symptoms, you may not be able to tell if you or your partner is infected.
Cancer and warts that can be caused by HPV
Genital warts are often the only visible sign that someone has an HPV infection. These are small growths that can appear on or inside the sex organs several weeks, months, or even years after sexual contact. Most often, the HPV virus clears completely, but sometimes the virus stays hidden and reactivates later in life to cause genital warts. The two HPV types responsible for 90% of the cases of genital warts are HPV 6 and 11.
Cervical cancer, or cancer of the cervix, is almost exclusively caused by HPV. In Canada, about 1,500 women are diagnosed each year and 400 die from this type of cancer. Around the world, the four HPV types most commonly associated with cervical cancer are HPV 16, 18, 31 and 45.
Anal cancer, or cancer of the anus, is rare but increasing. The HPV type most commonly associated with anal cancer is HPV 16.
Penile cancer, or cancer of the penis, is a more rare type of cancer representing less than one percent of cancers in men. Generally, penile cancer affects the head or foreskin of the penis rather than the shaft of the penis. The two HPV types most commonly associated with penile cancer are HPV 16 and 18.
Head and neck cancer, also known as mouth and throat cancer, includes cancer of the mouth as well as cancer of the nose, sinuses, salivary glands, throat, larynx and lymph nodes in the neck. HPV-related head and neck (mouth and throat) cancers are increasing. These are linked to the spread of HPV by having oral sex with a person who is infected with the virus. The HPV type most commonly associated with head and neck (mouth and throat) cancer is HPV 16.
Vulvar and vaginal cancers, are more rare types of cancers representing approximately 3% of all gynaecologic cancers, but the number of women affected is increasing. There are two types of vulvar cancer. One is associated with HPV infection and tends to occur in younger women. The other is associated with vulvar skin disease and is more frequently found in older women. The two HPV types most commonly associated with vulvar and vaginal cancers are HPV 16 and 18.