HPV: the vaccine and the test answer different questions

Two different things get spoken about as “the HPV one,” and they are not interchangeable. One is a vaccine that prevents an infection. The other is a screening test that looks for an infection already present. Being up to date on the first does not take you out of the second — and in Québec the second is in the middle of changing.

What the vaccine does

The nonavalent vaccine protects against seven high-risk HPV types, which together account for about 90% of all cervical cancers, plus two low-risk types responsible for about 90% of anogenital warts. It works before exposure to the virus. It is prevention, not treatment: it does not clear an infection that is already there.

In Québec it is given at school. Since the 2024–2025 school year the schedule is a single dose of the nonavalent vaccine in grade 4, and the second dose in secondary 3 is no longer required for young people with normal immunity. The vaccine is free for young people aged 9 to 20, and for people aged 21 to 45 who are immunosuppressed or living with HIV.

The adult programme keeps moving

Beyond those groups, Québec has run temporary measures for adults — including a time-limited offer of the bivalent vaccine to healthy adults aged 21 to 45, set to run until the available doses were used up rather than until a fixed date. Eligibility decided by supply is eligibility that changes, so confirm what is current when you book rather than relying on an article.

What the screening test does

Screening asks a different question: is there a high-risk HPV infection now? The HPV test detects the presence of the virus itself. The Pap test it is replacing detected abnormalities in cervical cells associated with persistent HPV infection — the consequence rather than the cause.

In Québec, screening is offered from age 25 to age 65. With the HPV test the recommended interval is every five years, where the Pap test was every three.

Why it starts at 25

Below 25, transient HPV infections that resolve on their own are common, and cervical cancers are rare. Testing earlier mostly finds infections that were going to disappear on their own, and every one of those findings sets off follow-up that carries its own cost.

Québec is changing the first-line test right now

Since 2022 the province has been moving to the HPV test as the primary screening test in place of the Pap. The transition is progressive rather than province-wide on a single date: it advances laboratory cluster by laboratory cluster, and which test you are offered can depend on which laboratory network serves the place you are tested. It is a reasonable thing to ask about at the appointment.

The longer interval is not a loosening of standards. The reasoning behind it is that the risk of a precancerous lesion or a cancer appearing in the five years following a negative HPV test is lower than the comparable risk after a Pap.

Why vaccination does not end screening

About 90% is not 100%. The types covered by the nonavalent vaccine are the ones behind most cervical cancers, not all of them, so an infection with a type outside that group stays possible. The vaccine also acts before exposure, which means anyone vaccinated as an adult may already have encountered the virus. Québec's own framing is the useful one: HPV vaccination and cervical cancer screening are the two most effective ways to prevent this cancer. Two, not one.

Where to start

If you have never been vaccinated, that is one conversation. If you are between 25 and 65 and cannot remember your last screening, that is a different one, and the answer to it does not depend on your vaccination status. HPV vaccination and the HPV screening test are both done here, and which one you need is not something you should have to work out on your own.