Your Health

HPV & You

How to reduce your risk of developing cervical cancer

BY LINDA COOTE
Winnipeg Health Region
Wave Magazine, Fall 2009

What is Human Papillomavirus (HPV)?

Human Papillomavirus (HPV) is a virus that can infect many parts of the body in both men and women. There are over 100 different types of HPV. Some are low-risk and some are high-risk based on their potential risk of cancer. There are 15 known high-risk types of HPV that can cause pre-cancerous lesions and cervical cancer; they can also cause oral cancer and anal cancer.

Most of these infections are cleared by the body's immune system without the individual knowing that they had an infection. Persistent infection of a high-risk virus can lead to early changes in the cervical cells (dysplasia). If these changes are not detected by screening and treated, they may progress to cancer of the cervix (lower part of the woman's uterus that leads into the vagina). Some low-risk types can cause genital warts and even some dysplasia. These dysplasias usually do not progress to cancer.

How does someone get HPV?

Some types of HPV can be spread during sexual contact with a person who is already infected. Sexual contact includes skin-to-skin contact with the vagina, vulva (the outside parts of a woman's genitals), penis, scrotum, anus and/or the mouth. HPV is estimated to be one of the most common sexually transmitted infections (STI) in Canada and around the world. Any person who has sexual contact can get the virus.

What are the signs and symptoms of an HPV infection?

Most HPV infections occur without any symptoms. It is easy for people who are infected to pass it on to others without knowing it. It is possible to have more than one type of HPV infection at a time. While most HPV infections go away with no treatment, some do not and can go on to cause skin and genital warts, or more importantly, cancers of the cervix, or, more rarely, cancers of the vagina, vulva, rectum, penis and mouth.

How can someone prevent or reduce the risk of getting HPV?

The only way to prevent HPV infection is to not have sexual contact (skin-toskin contact) with the vagina, vulva, penis, scrotum or anus. You can reduce your risk by:

• Delaying sexual activity.
• Limiting your number of sexual partners.
• Using condoms can offer protection from HPV and other sexually transmitted infections, but skin that is not covered by the condom can still be exposed and infected.
• Considering your partners' sexual history, as they may not know they are infected with HPV.
• Practising good health habits, which include: not smoking, eating a healthy diet, getting plenty of exercise and rest.
• Getting immunized with the HPV vaccine to reduce the risk of infection, pre-cancerous lesions and cervical cancer. Current HPV vaccines only protect against some HPV types.

Once your body matures and if you choose to become sexually active, it is recommended that you see your doctor for regular checks including Pap tests of the cervix. For more information on sexuality education, visit the Sexual Education Resource Centre Manitoba.

What is the link between HPV infection and cervical cancer?

HPV can cause changes in the cells on the cervix, called cervical dysplasia (abnormal cells). Over time, these changes can progress, stay the same or get worse. If these changes are severe and are not treated, cancer of the cervix can develop. HPV is considered to be a causal factor in virtually all cases of cervical cancer, and about 70 per cent of cancers are associated with HPV types 16 and 18, two of the HPV types targeted by the HPV vaccine.

How many women get cervical cancer?

Approximately 1,350 Canadian women are diagnosed with cervical cancer each year; about 400 women annually die from the disease. In Manitoba, approximately 45 women are diagnosed with cervical cancer each year and approximately 15 deaths are reported each year.

What is the HPV vaccine?

HPV vaccines have been in development for many years. At this time, there is only one HPV vaccine that has been approved for use by Health Canada. When this vaccine is given before being exposed to HPV, it is highly effective in preventing infection from two of the HPV high-risk types. These high-risk types (Type 16 and Type 18) account for about 70 per cent of cervical cancers. The vaccine also protects against two low-risk types (Type 6 and Type 11) of HPV, which cause about 90 per cent of all genital warts.

The vaccine is given in three separate doses (needles/shots) in the upper arm over a six-month period. Clinical trials have shown that the vaccine is effective for at least five years. It is not known at this time whether a booster dose will be needed.

Why is the HPV vaccine recommended for women?

By preventing HPV infections that can cause pre-cancerous changes in the cervix, it is expected that the vaccine will reduce the rate of abnormal pap smears and the rate of cancer of the cervix. Currently, the vaccine is only approved for use in women by Health Canada. Therefore, unlike most other vaccines, the goal of the program is to reduce the risk for women who are vaccinated, rather than to reduce the spread of HPV in the whole population. Women who receive the vaccine should continue to be screened regularly with a Pap test. This is because the vaccine does not protect against all types of HPV that can cause cancer and because the vaccine has not been studied long enough to show how many cancers will be prevented.

For more information on screening, women should talk to their health-care provider or contact the Manitoba Cervical Cancer Screening Program.

Who should receive the vaccine?

The National Advisory Committee on Immunization (NACI) recommends the vaccine for females between the age of nine and 26 years. The vaccine is thought to be most effective before the onset of sexual activity; however, females between the ages of nine and 26 years can still receive the vaccine even if they have already been sexually active. Women who are already sexually active may be infected with an HPV type contained in the vaccine, but they can still benefit from protection against the other HPV types the vaccine protects against. Females who have had previous Pap test abnormalities, including cervical cancer, or have had genital warts or known HPV infection, could still benefit from the vaccine. These women may not have had infection with the HPV types included in the vaccine and are very unlikely to have been infected with all four HPV types contained therein. It is therefore recommended by NACI that these women receive the vaccine. However, they should be advised that there is no data to suggest that the vaccine will have any therapeutic effect on existing cervical lesions. The vaccine does not treat existing HPV infections, genital warts or cervical abnormalities.

Who will be offered the vaccine in Manitoba?

Manitoba Health and Healthy Living has introduced a voluntary, publicly funded vaccine program for Grade 6 girls only. The program will be delivered by public health nurses. Before any female receives the immunization, information about HPV infections, the vaccine, and a consent form will be provided to parents and/or legal guardians.

Who should not receive the vaccine?

Females under the age of nine or over the age of 26. The safety and effectiveness of the vaccine has not been evaluated in children younger than nine years. In addition, the vaccine should not be given to:

• Pregnant women.
• Anyone who is allergic to any of the ingredients listed in the vaccine package information.
• Individuals who develop symptoms of hypersensitivity after receiving a dose of the vaccine.

Is the HPV vaccine safe?

Yes, the vaccine is considered safe, but as with all vaccines, adverse events may occur, including rare, life-threatening reactions. Health Canada has done a scientific review of the quality, safety and efficacy of the vaccine and has approved it for use.

What are the possible side-effects?

The most commonly reported side-effects of this vaccine are: pain, swelling, itching and redness at the injection site, fever, nausea, dizziness, headache and vomiting. Fainting has been reported. Fainting can occur after vaccination, most commonly among adolescents and young adults. As with any vaccine or drug, severe, allergic, life-threatening (anaphylactic) reactions may occur, with symptoms such as: difficulty breathing, wheezing (bronchospasm) and hives or rash. It is a routine public health practice to observe individuals who have received a vaccine for at least 15 minutes following immunization. As with other vaccines, side-effects that have been observed after vaccination include: swollen glands (neck, armpit or groin). Guillain-Barré syndrome, a rare form of paralysis that is usually temporary, has been reported, but a confirmed link to the vaccine has not been established. For additional information on other rarely reported side-effects, please consult your public health nurse or doctor.

Linda Coote is a registered nurse and a manager with the Winnipeg Health Region's Health Links - Info Santé help line.

	About Wave Wave is published six times a year by the Winnipeg Health Region in cooperation with the Winnipeg Free Press. It is available at newsstands, hospitals and clinics throughout Winnipeg, as well as McNally Robinson Books. Read the Fall 2009 issue of Wave