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Ask a Family Doctor: Why are pre-teens offered the HPV vaccine?

teen boy getting needle

Q: My son is in Grade 7 (in Ontario) and I learned the HPV vaccine program starts in this year and boys can get it now too. Why do pre-teens get this vaccine? (Isn’t it something to do with sex?)

To answer this question, I’ll need to give you a bit of quick background.

Human Papillomavirus (HPV) is one of the most common sexually transmitted viruses in North America. There are about 100 strains of the virus, and several high-risk strains are known to cause cervical cancer and other gynaecological cancers in women as well as other types of cancers that affect men and women (like oral and anal cancer). Most people can clear the virus from their system, and actually don’t even have any symptoms. Some strains cause warts on the genital, vaginal or anal areas (or very rarely in the mouth) a few weeks or months after infection. The warts aren’t cancer.

But, some types of HPV can cause cell changes that could lead to cervical cancer in women, penis cancer in men (rare), or anal / mouth cancer in both men and women. Each year in Ontario, there are 1,090 new cases of cancer and 14,666 new cases of genital warts attributable to HPV.

Yes, HPV is a sexually transmitted disease – but we don’t give pre-teens the vaccination because we think they are sexually active. In fact, the vaccine is most effective if you haven’t already been exposed to the virus and that’s why Ontario’s program works with students in Grade 7. Evidence actually shows that most pre-teens aren’t yet sexually active. Canada’s National Advisory Committee on Immunization recommends vaccination in Grade 7 or 8 because receiving the vaccine at this age (12 going on 13, typically) maximizes the benefits of the vaccine. Studies also show the HPV vaccine produces a higher immune response in pre-teens than it does in older teens and young women.

Since 2007, girls in Grade 8 in Ontario have been offered the HPV vaccine for free. The HPV consists of two doses, given six months apart, through schools now to Grade 7 students. Three doses are required if first dose is on or after 14th birthday.

You are correct in that the vaccine is now offered to boys as well. This change occurred in April 2016. The vaccine helps prevent boys from getting HPV, which can lead to cancer of the penis, throat and mouth, and also helps prevent them from spreading the virus to their sexual partners. Again – this is not because we think your seventh grader is having sex. This helps prevent him from getting the virus and spreading the virus when he does become sexually active, whatever age he may be at that time.

The HPV vaccine covers many, but not all, strains of HPV.  The vaccine currently provided by Public Health covers four major strains (responsible for about 70% of cervical cancer).  A newer vaccine, not currently provided by Public Health, covers nine strains (responsible for about 90% of cervical cancer). Both vaccines prevent about 90% of genital warts.  Speak to your physician to find out more information about the newer vaccine, which can be obtained through your physician’s office; however, you will need a prescription, and the cost is approximately $175 per dose.

Even after getting the vaccine, it’s important to take measures to practice safe sex. Speak to your pre-teen or teen about this. Male condoms worn properly during sex can help prevent spread of HPV and other sexually transmitted infections. Vaccinated women should get screened for cervical cancer through regular PAP tests after age 21.

If you need more information on HPV or the vaccine, here are some great resources: Toronto Public Health  and Health Canada

Or make an appointment with your son’s family doctor to discuss the vaccine. While the vaccine is offered through the school-based system through Public Health Units in Ontario – this varies by province – you can also speak to your doctor or a Public Health nurse at a clinic near you wherever you live.

About the author

Dr. Sharon Domb

Dr. Sharon Domb is a family physician and member of Sunnybrook’s Academic Family Health Team.
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