In a new report released today, NACI – an independent body of volunteer vaccine experts – is also calling on Canadians aged 18 to 49 to get mRNA vaccines at least six months after receiving their second . With the virus still circulating widely, advisory committees in other countries – like the one working with the U.S. Centers for Disease Control (CDC) – have been recommending an expansion of the recall campaign to cover more people for weeks.
NACI’s recommendation gives provinces and territories the flexibility to significantly expand the currently limited recall campaign.
COVID-19 vaccines authorized by Health Canada have been shown to be very effective against infections, serious illnesses, hospitalizations and death. The NACI said it is recommending booster shots now, as emerging data suggests protection against infection wanes over time for those who have completed a two-dose vaccination schedule.
“Decreasing protection against infection could contribute to increased transmission, as infected people can be a source of infection for others,” the committee said in its report. “Therefore, a booster dose can provide longer lasting protection to reduce infection, transmission and, in some populations, severe illness. “
While the NACI says all adults 50 and over should receive a third injection, it doesn’t insist that younger ones receive a booster. It says a third dose is “strongly recommended” for people 50 and over, while a booster for people 18 to 49 is a “discretionary recommendation.”
The committee indicates that the 18-49 year old cohort should take into account local epidemiological conditions (number of cases in a given area), any underlying health problem and the time that has elapsed between the first and second. dose before rolling up his sleeves for a reminder.
Dr Matthew Tunis, executive secretary of NACI, said early evidence suggests that people who had a short interval between their first two doses may face a higher risk of declining protection and should consider receiving a treatment. reminder as soon as they are eligible.
While Pfizer and Moderna recommended that a second injection be given 21 or 28 days after the first, Tunis said that a longer time interval between those first two injections might actually offer more protection for a longer period. .
Revision of NACI terminology
While the NACI uses the term “booster dose” for this third injection, the committee said it is also reviewing emerging evidence that suggests that a third injection should be considered part of the “primary series” – which A person should not be considered fully vaccinated until they have had three doses of an mRNA product.
“NACI will adjust terminology as needed,” the committee said.
While recommending booster doses for all adults, NACI said the top priority for provinces and territories right now should be getting people immunized who have not yet received their first two doses.
The rates of new COVID-19 infections, hospitalizations, intensive care admissions and death continue to be highest among unvaccinated people, the committee said.
“The data we currently have suggests that vaccines are quite resistant to severe consequences,” said Dr. Theresa Tam, Chief Public Health Officer of Canada. “But there is definitely a directional downward journey in terms of the vaccine’s decrease in effectiveness over time against asymptomatic infection and any symptoms. “