Fully vaccinated: How many doses will be given, and how will Canada decide? – Nation

As provinces continue to increase doses of the booster COVID-19 vaccine, questions arise about whether booster vaccines can be considered part of a full vaccine series – and are necessary. for a Canadian to be considered “fully vaccinated”.

The consideration of adding a third dose to the “major series” of mRNA vaccines could cause widespread changes to public health measures – including the receipt of vaccines for restaurants and stores. other business establishments. It also comes amid the spread of a more infectious COVID-19 Omicron variant.

Speculation on whether the main series of vaccines could be expanded to three doses comes amid comments from the National Advisory Committee on Immunization (NACI) and the Public Health Agency of Canada. last Friday.

Asked if the booster would eventually be considered part of a major vaccine series, public health director Dr Theresa Tam said the booster dose would only be maintained at “recommended levels”. strong”, but does not reduce the likelihood of it being added again. Vaccine data comes to light.

“So it’s a bit complicated. But the bottom line is that if immunity wanes over time, a supplement or medicine that boosts your immune system will help, at least in the short term, boost your antibody levels and improve your quality of life. overall immune response as well as endurance. of feedback,” said Tam.

“But I think it’s partly because we’re doing clinical trials and observational studies as the pandemic progresses.”

Tam said that due to time constraints caused by the pandemic, researchers have not yet been able to observe the effects of the doses in the long-term for the general public, but added that the NACI is currently reviewing additional doses. supplement for people with underlying immune conditions. as part of the “main chain”.

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In a statement sent to Global News Friday, Health Canada said that the government will continue to monitor existing data on booster shots for the general population and to “make additional recommendations, if need”.

“The need for additional injections to the general population is eventually possible, but not at this time,” reads the statement.

Currently, the mRNA vaccines offered by Pfizer and Moderna will be given as a series of two injections so that a person receives full protection and immunization status.

Pfizer executives told CNBC on Wednesday that people may need a fourth dose of COVID-19 sooner than expected, citing preliminary research on the Omicron variant.

Laboratory research from Pfizer and BioNTech still shows that the third injection is effective against the variant, despite its two-dose series – while still providing protection against severe disease. important – was significantly reduced to protect against infection of the new strain.

On the other hand, experts like Dr Gerald Evans, chair of infectious diseases at Queen’s University, have voiced support for a third dose as part of a full series, although he is more skeptical of who can make the final decision on the elements constituting the full series.

“My general belief, my opinion at this point is that this vaccine is probably a three-dose vaccine,” Evans said.

“The decision to fully roll it into a three-dose regimen will ultimately depend on the province and territory, as healthcare administration remains within those jurisdictions,” he said.

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While Health Canada is the governing body responsible for approving vaccines, the NACI can only make recommendations “based on current scientific evidence and expert opinion” – no voice. provinces decided to deploy a series of three doses.

“In Canada, provincial and territorial jurisdictions may choose to provide an additional dose of vaccine to specific populations to enhance their protection against COVID-19,” reads Statement by Health Canada.

“This would be considered off-label use as Health Canada does not allow a three-dose regimen for any vaccine to be authorized in Canada.”

While no facility has officially added booster vaccines to the current vaccine series, some provinces have begun to actively implement booster vaccination campaigns. Most recently, Ontario announced Friday that fully immunized people 18 years of age and older will be eligible for a booster shot starting January 4.

According to Evans, giving three or even four doses of the vaccine can still be considered part of the “regular schedule” and is common to other shots.

Vaccination schedules such as those for human papillomavirus (HPV) and hepatitis B include three doses given at specific intervals.

Evans says that preliminary studies suggest that current mRNA vaccines must be administered in a three-dose regimen.

“Even our Canadian data is, to some extent, showing a bit of weakness right now – it takes about eight months or so for that to happen when you have an eight to 12 week gap between first and second dose,” he said.

And while the strong recommendation by Tam and Health Canada for people, especially immunocompromised groups, remains, the country’s health authorities say that any impairment is “widespread.” Any such protection against severe disease in the general population has yet to be observed.

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However, as to how many vaccines could be added to the vaccine series or boosters for people to use in the future, Evans said we could look at the biennial shots. like flu if it exceeds four doses.

“I think we’re looking at a three-dose series and then with the potential, you know, with the possibility of other variants, especially if they move out the Omicron variant vaccine, that would be the answer,” he said.

“You might need one more vaccine with the variant, but it would be just one shot at that point, and it would mask an extremely mutated variant like you see with Omicron.”

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