Research raises questions over delayed second vaccine doses for seniors
2021-03-25 from ctvnews.ca
More questions are being raised about how long second shots of the COVID-19 vaccine can be delayed for seniors and other immunocompromised people.
The federal body that advises how vaccines be deployed said Thursday it's reviewing a Vancouver study that found long-term care residents had a weaker immune response to their first dose of the Pfizer-BioNTech vaccine than younger healthy adults.
After supplies slowed to a trickle earlier this year, the National Advisory Committee on Immunization said provinces and territories can delay second doses by as long as four months.
That's instead of the recommended schedule that spaces out the two-dose Pfizer-BioNTech and Moderna vaccines by three to four weeks, and the AstraZeneca product by four to 12 weeks.
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