The National Advisory Committee on Immunization (NACI) have given its approval of extending the time period between when people receive their first and second dose of the COVID-19 vaccine in Canada.
In a statement on Wednesday, NACI – an external advisory body that provides input to the Public Health Agency of Canada (PHAC) – said it has considered evidence from recent scientific studies on efficacy and effectiveness of COVID-19 vaccines in preventing various health outcomes such as infection, symptomatic disease, hospitalizations and death from COVID-19.
“While studies have not yet collected four months of data on vaccine effectiveness after the first dose, the first two months of real-world effectiveness are showing sustained high levels of protection,” NACI states.
As such, NACI said extending the interval between doses “was shown to be a good strategy through modelling, even in scenarios considering a six month interval and in theoretical scenarios where waning protection was considered.”
And in the context of limited vaccine supply, NACI said jurisdictions should maximize the number of individuals benefitting from the first dose of vaccine “by extending the interval for the second dose of vaccine to four months.”
NACI also noted that extending the dose interval to four months allows for the opportunity to protect the entire adult population within a short time frame.
This, the board added, “will not only achieve protection of the adult population, but will also contribute to health equity.”