A panel advising the Public Health Agency of Canada (PHAC) on vaccines has recommended another COVID booster shot for certain vulnerable groups starting this month.
“Evidence suggests that a fourth dose of an original monovalent COVID-19 vaccine provides an increase in vaccine effectiveness (VE) against infection,” wrote the National Advisory Committee on Immunization (NACI) in a guidance report, released by PHAC, on March 3.
“However, waning of protection is observed over time, consistent with the waning of protection after two or three doses.”
As first reported by Blacklock’s Reporter, the NACI recommended “an additional COVID-19 booster dose in the spring of 2023” for individuals at risk of severe illness due to the virus….