Quebec could reevaluate baby vaccines as post-pandemic viruses change needs

Quebec is evaluating whether part of its vaccination schedule for babies and toddlers needs modification in the wake of the COVID-19 pandemic, which saw different diseases and viruses thrive.

For example, Quebec currently offers babies two doses of the vaccine Synflorix, which fights against 10 strains of pneumococcal disease.

These doses are given at the two- and four-month appointments.

Additionally, babies get one dose of Prevnar-13 at their 12-month appointment.

"Other provinces use three doses of Prevnar-13 at two, four and 12 months of age," said Dr. Nicholas Brousseau with the Comité sur l'immunisation du Québec (CIQ). "These two schedules offer good protection and show similar effectiveness."

However, according to CIQ Chair Dr. Caroline Quach Thanh, the number of children catching invasive pneumococcal diseases (IPD) jumped after the COVID-19 pandemic.

"An increase in respiratory syncytial virus (RSV) infection was a risk factor for IDP," she explained. "The addition of Prevnar-13 at 12 months of age seemed to control the transmission of disease."

WHO'S IN CHARGE?

For its part, Quebec's Health Ministry says it takes its directives from the CIQ.

"The CIQ considers such a schedule to be safe in terms of reducing the burden of disease," the ministry tells CTV News. "The CIQ's advice may be revised according to the epidemiology of the disease and the availability of new vaccines."

The health care system is not federally dictated in Canada, so there are variations from province to province.

"There are several vaccines against meningitis (meningococcal vaccines) that are authorized in Canada, and they don't cover the same strains," explains Brousseau. "The main serogroup responsible for meningitis varies according to the province, so the specific vaccination strategy varies slightly by province."

It could be said that Quebec often marches to the beat of its own drummer -- though they usually "get it right," says Dr. Christos Karatzios, an assistant professor of pediatrics at the McGill University Health Centre (MUHC) division of infectious diseases.

"Whereas across many places in the world, pneumococcal vaccination was given at two, four, six and 12 months of age, Quebec, from the get-go omitted the six-month dose and got better antibody responses at the 12-month mark when they allowed more time to elapse between vaccine doses," he tells CTV News.

Karatzios notes other provinces have often taken note and followed suit.

"See what happened with the original Prevnar-13 being dropped at six months, the Gardasil vaccine series, and, of course, the COVID-19 vaccination schedules," he said.

Nevertheless, Karatzios says he chose -- and paid -- to have his children immunized with Prevnar-13 rather than Synflorix.

"We had good evidence for it working and was uncomfortable with Synflorix as it lacked three pneumococcal types that Prevnar-13 had," he said. "I am glad I did because, as you can see, the government brought back Prevnar-13 for the 12-month dose, didn't they?"

AN IMPERFECT SCIENCE

Now, two new pneumococcal vaccines have just been authorized in the country -- Vaxneuvance and Prevnar-20.

"The question of interest is whether or not they should replace Synflorix and Prevnar-13," Brousseau explains.

The Comité sur l'immunisation du Québec says it plans to publish recommendations regarding any potential changes to the province's pneumococcal vaccine schedule in the upcoming months.

"Whether or not children who already received their vaccination (Synflorix or Prevnar-13) will need an additional dose is one of the questions being evaluated," Brousseau explains.

For his part, Karatzios admits vaccine schedules aren't a perfect science.

"In Quebec, we used to give Prevnar-13, and then they stepped it back to Synflorix a few years back and then re-added Prevnar-13 at the one-year mark when it was realized that the strains not covered showed up again," he said. "So, here we are now. The rest of the world is on 13 and maybe 20 in the future, and I am uncertain what the next steps will be here."

Quebec has already implemented a Prevnar-20 program for children who are considered immunocompromised.

Brousseau emphasizes that the most important thing parents can do is ensure their children get all their vaccines.

"There is a very small proportion of children who did not receive their pediatric vaccines -- about one per cent of children -- and it would be very beneficial for them to receive their primary vaccinations," he said