The opening practice session at the LGT World Women's Curling Championship was cancelled on Tuesday, one day after the World Curling Federation announced that two positive COVID-19 cases had been identified in pre-competition screening.

All 14 teams were originally scheduled to practise on Wednesday at the Markin MacPhail Centre to prepare for the start of round-robin play on Friday in the curling bubble.

"Tomorrow's practice has been cancelled to allow Alberta Health to continue their testing and investigation," WCF media head Christopher Hamilton told The Canadian Press in an email on Tuesday afternoon.

The initial positive result was discovered in day-zero testing during a pre-competition quarantine period last Friday, the WCF said. The second positive case was identified within the same team after enhanced testing protocols on Sunday.

There was no immediate word on which team was affected.

The WCF said all other tests since teams arrived in Calgary have returned negative results. The WCF, Curling Canada and Alberta Health are now following a COVID-19 response plan.

Kerri Einarson's Manitoba-based team will represent Canada at the world championship. The foursome was already in the bubble -- along with several top international teams -- to compete in this month's Grand Slam events.

Recent arrivals to Calgary, meanwhile, were isolated in a quarantine hotel at a different location, where they'll remain while protocols outlined in the response plan are followed.

Medical officials, in consultation with provincial health authorities, will make the final decision on the affected team's participation.

During a pre-competition video call with media on Tuesday, Einarson was asked for her reaction to the news of positive tests.

"When I woke up the other morning I was like, 'Oh no,'" she said. "But I knew that it wasn't in our bubble here so I knew that it would still be a go. You never want to hear about positive cases.

"You just want to make sure everyone is healthy and safe."

The practice schedule on Thursday remained in place. Hamilton said organizers are exploring options for rescheduling Wednesday's cancelled sessions, but there was "no additional information at the moment."

The April 30-May 9 world championship serves as the main Olympic qualifier for the 2022 Beijing Games. Canada is scheduled to open against reigning Olympic champion Anna Hasselborg of Sweden on Friday.

Other teams in the field include China, the Czech Republic, Denmark, Estonia, Germany, Italy, Japan, South Korea, Russia, Scotland, Switzerland and the United States.

Alberta Health and the Public Health Agency of Canada approved Curling Canada's plan to host events in a controlled environment without spectators. The Canadian women's championship kicked off a run of seven bonspiels last February.

The first three domestic competitions went off without a hitch, but there was a COVID-19 scare at the world men's championship earlier this month. Four positive tests were later deemed to be "false positives" and the playoffs resumed after a one-day delay.

There were no COVID-19 issues during the two Grand Slams, which are owned and operated by Sportsnet. The world women's championship is a WCF event hosted by Curling Canada.

For its bubble plan, the domestic federation adopted many elements from Hockey Canada's operation of the world junior men's hockey championship in Edmonton from Dec. 25 to Jan. 5.

International teams didn't arrive in Canada by charter flights as the hockey players did, but instead flew commercially. A negative test taken less than 72 hours before travelling to Calgary was required.

Upon arrival, athletes and team personnel began a week-long "managed quarantine protocol'" with four separate tests taken during that span before curlers can be cleared to compete.

Teams are confined to the arena and their hotel across the Trans-Canada Highway, and drive themselves back and forth. Masks are mandatory outside hotel rooms and off the field of play.

This report by The Canadian Press was first published April 27, 2021.

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