The Montreal Canadiens, Edmonton Oilers, Ottawa Senators and Columbus Blue Jackets are the latest teams to be shut down by COVID-19 as the NHL limps towards its holiday break.

The clubs were put on ice Monday until at least Dec. 26, joining the Toronto Maple Leafs, Boston Bruins, Colorado Avalanche, Detroit Red Wings, Florida Panthers and Nashville Predators.

The Calgary Flames, who have endured the largest outbreak across the league so far this season with 32 people impacted, said their facility has re-opened to members of the organization that have remained negative throughout daily testing.

It will, however, be a lonely place with 19 players and 13 staff members still in protocol.

The additions of Edmonton, Montreal, Ottawa and Columbus to the list of teams sitting at home means nearly one-third of the NHL is currently sidelined by the pandemic's latest wave fuelled by the fast-spreading Omicron variant.

The league issued a statement Monday with a line that's been repeated over the last week, indicating the decision to shutter the Canadiens and Blue Jackets was made "due to concern with the number of positive cases within the last several days as well concern for continued COVID spread."

The Oilers then announced defencemen Darnell Nurse and William Lagesson have been added to protocol, joining five teammates and head coach Dave Tippett. The team subsequently posted to Twitter its facility would also be closed through the Christmas break.

The Senators, who said assistant coach Davis Payne has been added to protocol, tweeted the team won't practice again until after the break for "precautionary reasons."

The league also announced Monday afternoon that Tuesday's game between the Pittsburgh Penguins and New Jersey had been scrapped.

With more than 140 players and team staff currently in COVID-19 protocol, the NHL has been forced to postpone 43 games so far this season, with 38 coming since last Monday alone.

All but one NHL player — Detroit winger Tyler Bertuzzi — is vaccinated against the coronavirus.

The Canadiens announced Sunday they were shutting down until Dec. 26 as a preventive measure before the NHL made the move official less than 24 hours later. Montreal, along with the six other Canadian-based clubs, had already seen its remaining games before Christmas postponed following the league's decision Sunday to temporarily pause cross-border travel.

The NHL also said it would be announcing a decision with the players' association on participation at the 2022 Beijing Olympics later this week, but the string of postponements related to COVID-19 has almost certainly paved the way for the league to pull out.

The Flames, meanwhile, tweeted that players and staff in protocol will be returning to the facility over the next week "as allowed after completing their required isolation period as per (Alberta Health Services) recommendations."

The Leafs announced Monday two members of their support staff have entered protocol. Toronto has seven players, including captain John Tavares and No. 1 goalie Jack Campbell, in isolation along with head coach Sheldon Keefe and assistant Spencer Carbery.

Canadiens winger Brendan Gallagher spoke with reporters Sunday — prior to the team being shut down — for the first time since he was sidelined by the coronavirus earlier this month.

The 29-year-old said he experienced some "pretty tough symptoms" the first couple of days.

"It got me hard … just laying there, fighting it," Gallagher told reporters in Brossard, Que. "But after two days I was good, and then it was eight days of me (quarantining) with my thoughts and a little bit of boredom in the house. I did some cleaning, played a lot of video games, watched a lot of movies, made a lot of phone calls and checked in on the guys quite a bit.

"It took a while for me to get (COVID-19), but now that you went through it, you understand what everyone's been going through."

Gallagher added there's definitely been talk among players about a league-wide pause to the schedule.

"We're having those conversations, for sure," he said. "I understand the NHL's standpoint. We've got to get an 82-game season in — we have to.

"We knew we were going to have to deal with this, and this was a potential and a possibility."