Human Papillomavirus Viruses (HPV)
Very often, HPVs are spread during sexual activity—with or without penetration—involving direct contact (skin-to-skin) with the penis, scrotum, vagina, vulva, or anus of an infected person.
Anyone who has sexual relations is at risk of HPV infection. From 70% to 80% of men and women will become infected with HPV at least once in their lives. HPV infection is the most common sexually transmitted infection (STI).
Usually, a person infected with HPV has no symptoms or lesions, and can therefore unknowingly spread the virus to others.
Certain types of HPV can infect cervical cells, leading to persistent lesions. When these lesions are not detected early enough, they can become precancerous or cancerous after several years. Every year in Québec, about 325 women learn that they have cervical cancer and 80 die from it.
Other types of HPV cause anogenital warts (condylomata). While these warts do not cause cancer and generally disappear on their own, they are often unpleasant and embarrassing. Furthermore, treatment, when necessary, may need to be repeated a number of times.
HPV vaccination before the onset of sexual activity and screening for cervical cancer are excellent means for protecting against this form of cancer. Using condoms can reduce the risk of HPV transmission and must be used for any sexual activity (vaginal, oral, and anal). Nevertheless, since condoms do not completely cover all the skin in the genital area, HPV infection remains a possibility. On the other hand, condoms play a key role in preventing other STIs. Using condoms, therefore, is complementary to vaccination.
The role of vaccination is to produce defenses (antibodies) against the HPVs contained in the vaccines. The vaccines cannot cause HPV infection because they do not contain active viruses. They offer no protection, however, against other STIs.
No, because the vaccine does not provide protection against all cervical cancers, only those caused by HPV types 16 and 18, which account for about 70% of cervical cancers. Screening (Pap test) is the only means for detecting abnormal cervical cells that could later become cancerous. The procedure consists in examining the internal genitalia. This examination is not necessary before the individual becomes sexually active. While the Pap smear may be useful in early screening for abnormalities caused by HPV infection, it cannot—unlike the vaccine—prevent such infections. Consequently, they are complementary methods.
Since the program started on September 1, 2008, HPV vaccination has been offered in schools at no charge school to girls in grade 4 elementary school and in Secondary 3. From 2008 to 2010, it was also offered to girls born after August 31, 1990 who weren't reached by school vaccination clinics.
This criterion was changed on October 1, 2010. Vaccination is offered at no charge to girls who are younger than age 18 when they receive their first dose. Girls who received their first dose before age 18 and those who started vaccination before October 1, 2010 (regardless of age) can complete the course of vaccination at no charge. The vaccine is free for younger girls if they are at high risk of HPV infection and for women between the ages of 18 and 26 who are immunosuppressed or HIV positive.
Women age 18 years or older who have not initiated vaccination must pay the cost of the vaccine if they wish to receive it.
In February 2010, Health Canada authorized the use of Gardasil™ for boys and men ages 9 to 26 years. Nevertheless, boys are not offered free vaccination under Québec's HPV vaccination program.
Recent data have demonstrated that this vaccine could protect boys against genital warts (condylomata) and, in all probability, against a form of anal cancer associated with HPV. There is still no evidence that it can prevent cervical cancer in their female partners. Studies into this continue. Expert committees should give an opinion on the population benefits of vaccinating boys against HPVs.
The main objective of the vaccination program is to prevent cervical cancer, which is the second most common cancer among women age 20 to 44 years. Each year in Québec, about 325 women find out that they have cervical cancer and 80 die from it. In reality, however, many more women are affected by it.
For every case of cervical cancer, an estimated 50 to 100 women have precancerous lesions that require management and treatment. This amounts to 15,000 to 30,000 women. Moreover, about 68,000 women annually must consult a specialist for complementary tests as the result of screening revealing HPV-related anomalies. These clinical examinations can be repeated, unpleasant, and stressful. In some cases, they can be painful (biopsy, colposcopy, partial removal of the uterus, etc.).
The vaccine used in the vaccination program (Gardasil™) will also prevent most genital warts (condylomata), 90% of which are caused by HPV types 6 and 11 contained in the vaccine. In Québec, about 20,000 people are afflicted each year. Other than being embarrassing and unpleasant, anogenital warts can require treatment spread over a number of medical appointments. The infection generally disappears on its own in most people.
Because the human body responds best to the vaccine between the ages of 9 and 11 years. Moreover, the vaccine is more effective when administered before the onset of sexual activity. Since there is already a grade-4 elementary school hepatitis B vaccination program, the HPV vaccine is offered at the same time.
The hepatitis B vaccination program has been in effect since 1994 and, since fall 2008, uses a combined vaccine, which adds protection against hepatitis A and reduces the number of doses required. As a result, only two vaccination sessions are needed in grade 4 elementary school.
Very reliable data indicate that the vaccine is effective for an extended time in preventing precancerous lesions, which are the precursors of cervical cancer.
Questions, such as about the length of protection and the effectiveness of a new vaccination course, are not uncommon when a new vaccine has been approved for use. Assessment and adjustments, if necessary, provide responses to such questions. That is what happened with measles vaccination, when a second dose was added to the schedule.
Yes, as is the case with all vaccination programs, the HPV program is being systematically assessed. Assessment deals mainly with the program's effectiveness in achieving the objectives of reducing the spread of the disease, monitoring vaccine side effects, and determining the effectiveness of the extended schedule.
This program is not an isolated activity. It stands alongside other measures already in place to prevent sexually transmitted infections (STIs) and to encourage safe, responsible sex practices. Indeed, various prevention and promotion actions, particularly in schools, very specifically target youth issues and situations related to sexuality they may encounter.
Moreover, efforts continue to go into screening for cervical cancer, since women who have had HPV vaccination still need to have a Pap test.
Vaccination has proven itself by reducing, even eradicating, certain serious diseases. The case of the HPV vaccine is no exception. To the contrary, it prevents, in particular, precancerous cervical lesions as well as genital warts (condylomata). Beyond the studies conducted on the vaccines, this protection has been confirmed in countries where vaccination has been implemented for several years, such as in Australia. Concerned with the health of the general public, Québec public-health authorities are encouraging young girls to receive the HPV vaccine—a recognized effective, safe means of protection—and encouraging their parents to support them.