In an official Tuesday announcement, the NHL and the NHL Players’ Association (NHLPA) agreed to pause all games until next week, meaning five regular season games that were scheduled for Thursday will be postponed until after the Christmas break. The NHL has postponed a total of 49 games this season, which began on Oct. 12, all owing to COVID-related concerns.

The league will resume its regular season matches on Dec. 27; and team practices will recommence on Dec. 26.

On Tuesday, the NHL also announced stricter COVID protocols for all players and club personnel—including daily COVID testing—which will expire on Jan. 1, 2022, at the earliest.

Scores of NHL ice hockey clubs have been affected by COVID outbreaks in recent weeks. Last Friday, the Alberta-based Calgary Flames said that 32 team members (including 19 players and 13 staff) had been infected with COVID-19—the largest outbreak in the league. The hockey club confirmed that roughly half its roster tested positive after a Dec. 11 match against the Boston Bruins; as a result, the Flames scrapped or delayed six of their scheduled games.

“I’ve never seen transmission on this level…It [the Omicron variant] doesn’t require a huge window to move from person to person,” said Ian Auld, the Flames’ medical director and head physician, during a media call last Friday. Three of the Calgary Flames’ COVID-19 cases are confirmed to be of the Omicron strain; but Auld said he expected that the majority of the 32 infections will be confirmed as Omicron cases. All of the Calgary Flames players had at least two doses of a COVID-19 vaccine. Auld added that the club is currently investigating whether the outbreak occurred as a result of in-game transmission.

Across the NHL, over 70 players have been placed on the league’s “COVID-19 protocol” list, which means that the player has either tested positive and must self-isolate, or the player is a close contact of someone who received a confirmed positive test. To be released from the protocol, the athlete must exhibit no symptoms and test negative twice over 48 hours.

The league’s current COVID outbreak, coupled with a surge of recent infections in China, may affect a coming decision on whether NHL players will take part in the upcoming Beijing Olympics. Earlier this year, NHL players reached an agreement with the league and global ice hockey governing bodies that would allow NHL athletes to compete at the Beijing 2022 Winter Olympic Games for the first time in eight years.

The league and the NHLPA say they will announce a final decision on the matter in the next few days. The last time NHL athletes competed at the Olympics was during the 2014 Sochi Winter Games in Russia. The NHL didn’t allow its players to compete at the 2018 Pyeongchang Winter Games in South Korea owing to travel costs and scheduling conflicts with regular season games.

Other professional sports leagues in North America are also scrambling to tighten their COVID protocols and reschedule games as a result of recent Omicron outbreaks.

Over 70 National Basketball Association (NBA) athletes are currently in the association’s “COVID protocol,” meaning that they have tested either positive or inconclusive for COVID. Any NBA player who tests positive must spend at least 10 days away from his team, unless he tests negative twice in a 24-hour time frame; while unvaccinated players need to quarantine for one week and can resume playing once they test negative after the seven-day quarantine. The NBA has postponed seven games this season.

The National Football League (NFL) meanwhile was forced to delay three of last weekend’s games—the first such postponements the league has made this season. More than 130 NFL players have been placed on the league’s “COVID-19 reserve list.”