Image courtesy of BC Cancer
October 1 to 6 is HPV Prevention Week! We spoke with Laurie Smith and Amy Booth of the Global HPV Control team to learn more about why prevention is so important, and how HPV screening and vaccination can reduce cancer risk.
What is HPV?
HPV, or Human Papillomavirus, is a very common virus. There are over 100 types of HPV; approximately 40 of them infect the genital region and are transmitted sexually, through intimate skin-to-skin contact. Without vaccination, most sexually active people will have an HPV infection at some point in their life. People under 30 have the highest rates of infection.
Why is prevention so important?
Most types of HPV are harmless and asymptomatic – you may not even know you are infected. Most of the time an HPV infection will resolve on its own with no lasting negative consequences.
The different types of HPV are broadly classified as “low risk” or “high risk”. Low-risk types can cause genital warts but are not associated with cancer. High-risk types can lead to various cancers, but only if someone has a long-term, persistent infection. When HPV is detected early, the effects of an infection can often be treated before they lead to cancer.
You’ve likely heard of the link between HPV and cervical cancer. It’s true that almost all cervical cancer cases are caused by high-risk HPV. Because of this, cervical cancer is considered almost entirely preventable. Yet in 2024, an estimated 1,600 Canadian women were diagnosed with cervical cancer, and an estimated 400 died from this preventable disease.
The virus is not only a concern for people with cervixes. It’s also linked to other types of cancers, including:
- 80-90% of anal cancers
- 40% of vulvar and vaginal cancers
- 40-50% of penile cancers
- 25-35% of mouth and throat cancers (oropharyngeal)
Mouth and throat cancers are unfortunately on the rise in Canada, and many of these cases are linked to HPV.
Primary prevention strategies (vaccination)
We know it’s important to try to prevent harmful HPV infections. But how do we do it?
Getting vaccinated for HPV before you are exposed to the virus is the best method of prevention. HPV vaccines have been available in Canada for nearly 20 years. We now have decades of data demonstrating the safety and effectiveness of these vaccines, even during pregnancy. In British Columbia, HPV vaccination is part of the school-based vaccination program. Offering the vaccine to children in grade 6 provides the best immune response and helps ensure more people are already immune by the time they are adults.
The vaccine currently available in BC is the nonavalent HPV vaccine (HPV9) which protects against 7 high-risk HPV types, as well as 2 low-risk types. The vaccine offers nearly 100% percent protection against persistent infections that cause cervical cell changes, which can lead to cervical cancer.
While vaccination before exposure offers the best protection, the vaccine can still be very beneficial if one has already been exposed. Although HPV vaccination will not treat or cure an HPV type that is already present, it is very unlikely that a person has been exposed to all the types of HPV that the vaccine protects against. Therefore, getting a vaccine is still helpful for reducing your risk of contracting a future persistent infection.
In 2024, the National Advisory Committee on Immunization (NACI) changed their recommendations for the number of doses someone needs for full protection. These changes were in response to new data and recommendations from the World Health Organization (WHO). The new recommendations, which were adopted by BC in July 2025, are:
- 1 dose for people between 9 and 20 (inclusive)
- 2 doses for people between 21 and 45 (inclusive)
- 3 doses for those with weaker immune systems (for example, people living with HIV, or people who have had organ transplants)
Secondary prevention (screening)
Although HPV vaccination is one of the best approaches to prevent HPV-related cancers, secondary prevention is equally important. Secondary prevention involves early detection of a disease through screening and then early treatment to prevent further progression. For decades in BC and Canada, cervical cancer screening with the Pap smear has been highly successful at preventing deaths from cervical cancer. However, the Pap smear has some limitations. Thanks to research conducted here in BC – led by Dr. Gina Ogilvie and team – we now have even better tools at hand to prevent cervical cancer.
In January 2024, BC began to implement HPV screening for cervical cancer. HPV screening has been shown to detect cervical pre-cancer earlier and more accurately than the Pap smear. Many regions around the world have already adopted HPV screening for cervical cancer.
With HPV screening, the swab can be done by a healthcare provider in a clinic setting (when a cervical swab is required), or you can collect the vaginal swab easily, safely and effectively on your own at home. In addition, HPV screening has a very low “false negative” rate, so healthcare providers can be more confident that a person who tested negatively is at low risk of cervical disease. This means the time between screens can be extended from 3 to 5 years.
Currently, there are no screening programs for other HPV related cancers, including anal, vaginal, or vulvar cancer. However, during a routine dental exam, your dentist will examine the oral cavity for any abnormalities that could be related to oral cancer. For individuals who are high-risk for anal cancer (for example HIV positive individuals, or men who have sex with men), a digital rectal exam by a health care provider is recommended. Most importantly, if you have any abnormal symptoms that you are concerned about, please seek advice from a health care professional.
What's next?
If you are interested in learning more about HPV vaccination or want to know how you can receive the vaccine, you can ask your health care provider, a BC pharmacist or visit the Health Link BC website for more information.