OTTAWA - The National Advisory Committee on Immunization says seniors in long-term care homes need a COVID-19 vaccine booster immediately to protect them from the virus.

The new guidance was released Tuesday after reviewing evidence about waning immunity from the vaccine, the latest safety data and the spread of COVID-19 across the country.

The committee recommends long-term care residents and people living in seniors' homes receive another shot of an mRNA COVID-19 vaccine, as long as it has been six months since their last shot.

NACI says there are signs that vaccine protection might not last as long for seniors in congregate setting like long-term care as it does for other populations in Canada.

Canadian studies have suggested that even though people in long-term care had a good antibody response to two doses of vaccine, the majority of residents did not have a detectable level of antibodies against the Delta variant six months later.

Several provinces have already approved booster COVID-19 shots for people in long-term care, including Ontario, Saskatchewan, Alberta, and most recently, Quebec.

This report by The Canadian Press was first published Sept. 28, 2021.