The four positive COVID-19 tests that interrupted the men’s world curling championship are considered “false positives” from potentially contaminated samples, according to the World Curling Federation.
The men’s championship concluded late Sunday night with Sweden’s Niklas Edin winning a record fifth world men’s title.
No games were played Saturday because four participants, including one from a playoff team, tested positive for the virus in “exit” tests before leaving Calgary’s curling bubble.
None had symptoms of the illness.
Dr. Robert McCormack, the event’s chief medical officer, said it is protocol to confirm positive tests.
“When the next tests came back negative, it accelerated our investigation. If an individual who tests positive is symptomatic and clinical diagnosis and testing fit with this, no retest is done. But a retest is done if there are any questions, and to get further information,” McCormack said in a statement to Global News.
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All have tested negative in multiple re-tests since then, the WCF said Monday in a statement. All tests were conducted via PCR throat swabs.
McCormack said the tests were done in a private facility that was fully approved and accredited by AHS.
“According to Alberta Health, PCR testing remains the gold standard for COVID-19 testing,” the WCF said. “Very rarely, there are occurrences through sampling or testing processes when samples may become contaminated and a false positive may result.
“Following an investigation over the weekend, it appears that this may have occurred in this case and follow-up testing was undertaken.”
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All athletes and personnel considered close contacts of the four underwent testing Saturday with all results negative.
Every playoff team member was tested before and after each game Sunday with those results also negative, the WCF said. Hotel staff were also tested Sunday and cleared.
“With the original four positive test results now deemed as false positives, the integrity of the Calgary bubble remains intact,” the WCF declared.
“The change also allows international athletes who were considered close contacts, and who would have had to remain in isolation in Calgary for 14 days, will now be able to depart Calgary.”
The fifth of seven events in Calgary’s curling hub, the Humpty’s Champions Cup, gets underway Thursday.
McCormack said the event is looking at some additional testing because of the high incidence of disease in the local community and the significant number of variants of concern.
“Alberta Health and Curling Canada are in constant contact throughout this process, leading up to and during the time in the bubble, to not only ensure that our protocols are working, as they did in this situation, but that any learnings from this can be used to strengthen the protocols. We are working with Alberta Health on this every time we speak with them,” McCormack said.
–With files from Julia Wong, Global News