COVID-19 vaccine boosters recommended for long-term care residents, national advisory committee says

Canadian seniors living in long-term care homesand other congregate-care settings should get COVID-19 vaccine booster shots, Canada's vaccine advisory body recommends.

Residents of such sites, includingretirement homes and assisted-living facilities, "are at increased risk for COVID-19 infection because of their daily interactions with other residents and staff," said theNational Advisory Committee on Immunization (NACI) in updated guidance released onlineTuesday.

"They are also at increased risk for severe disease because of their age and underlying medical conditions."

The rise of the more transmissible delta variant is onereason to offer maximum protection to vulnerable people in congregate-living environments, the recommendation said.

The amount of time that has passed since residents received their initial vaccinations is afactor in the recommendationgiven that older adults may "have a less durable response to vaccines and/or past infection compared to younger adults."

"Older Canadians residing in congregate-living settings were prioritized for the COVID-19 vaccine when the vaccines were first authorized; therefore, many completed their COVID-19 vaccination series early in the vaccine rollout, leaving more time for waning should it occur," NACI said.

Manylong-term care residents had their initial COVID-19 shots spaced out overshorter intervals based on the manufacturers' guidance 21 days between doses for Pfizer-BioNTech (Comirnaty) and 28 days for Moderna (Spikevax).

Current evidence now suggests that longer intervals between doses result in higher immune responses, NACI said, and therefore the original schedule may have contributed to "more rapid waning of protection, including against variants of concern."

Potential signs of waning immunity in LTC homes

Dr. Allison McGeer, a medical microbiologist and infectious disease specialist at Mount Sinai Hospital in Toronto, said she welcomes NACI's recommendation because there isdata that suggests immunity may be waningamonglong-term care residents.

McGeeris the lead author of a recent preprint study (meaning it has not yet been peer-reviewed)that found much lower levels of neutralizing antibody response against coronavirus among long-term care residents compared to the staff whocared for them.

It's "probable" that booster shots will help, McGeer told CBC News after NACI's announcement.

Ontario long-term care homes have already started administering boosters, she said, and her group will be studying what happens with that demographic.

"This isour opportunity to make sure that we're doing everything we can [to protect long-term care residents]," McGeer said.

In addition to preventing serious illness and death, the goal of bolsteringprotection as much as possible is to prevent outbreaks in long-term care homes, which forceresidents back into isolation and drastically affects their quality of life, she said.

Boosters not yet needed for all seniors,expert says

Dr. Samir Sinha, director of geriatrics at Mount Sinai and University Health Network hospitals in Toronto, also applauded the move to provide booster shots to long-term care residents.

Although he would have liked to see the recommendation come out sooner, NACI was right to make itspecific to people living in long-term care or other congregate-living environments, Sinha said, noting it should not yet be extrapolated to apply to all seniors.

At this point, he said, he doesn't see a need for the recentU.S. recommendation that everyoneaged 65and older should be eligible for a booster shot to be applied in Canada.

"It's about degrees of risk," Sinhasaid.

Evidence of waning immunity, together with the risks of congregate living including contact with health-care workers who may not be vaccinated and the fact that people who live in long-term care homes are usually there because they have serious health conditions, are all reasons that booster shots are a good idea for seniors living in those settings, he said.

WATCH | COVID-19 vaccine boosters recommended for long-term care residents:

NACI recommends COVID-19 booster shots for seniors in long-term care

3 years ago

Duration 1:58

Amid a global debate over COVID-19 vaccine boosters, the National Advisory Committee on Immunization is recommending third doses for Canadas most vulnerable, especially seniors in long-term care homes.

The next group of people who should be approved for booster shots, Sinha said, should be seniors who rely onhome care because they share many of the same risk factors as those living in long-term care, including serious health issues and multiple caregivers coming in and out.

"A lot of community-dwellingolder adults are actuallyrelatively healthy. They do not have the [same] degree of risk," Sinha said.

It's important to be "very measured" with decisions about who gets booster shots, he said.

"A third of the world's population hasn't even received a first dose of the vaccine," Sinhasaid. "The longer that we have other populations that aren't even getting a single dose, it puts the entire global population at risk of new mutations or new variants."

Thatposes a bigger risk to most people than not getting a booster shot, Sinha said.

In its guidance, NACI noted that itsbooster shot recommendation for residents of long-term care homes is not the same as recommending a third dose as part of the initialvaccination schedule.

"The intent of a booster dose is to restore protection that may have waned over time in individuals who responded adequately to a primary vaccine series," the advisory committee said.

That's different than the recommendation NACI issued just over two weeks ago for moderately to severely immunocompromised Canadians.People who are immunocompromised should receive three doses of COVID-19 vaccine as part of the standard immunization schedule,NACI said, because they may not mount an adequate immune response to two doses in the first place.