“That’s also possible. Or it’s a problem with the test … but that’s less likely.”
AFL players, coaches and staff have been temperature tested daily as they visit their respective club headquarters, and tested with nasal swabs at least twice a week for the past month under strict AFL protocols.
McKenna returned negative results on multiple occasions earlier this month before receiving an irregular test result on Friday and then a positive test on Saturday, which led to the cancellation of Sunday’s AFL match against Melbourne.
Bombers coach John Worsfold said on Wednesday he had his doubts over whether McKenna actually had the virus.
“There’s some doubt in my mind. I don’t know if there is doubt in other people’s minds. We are waiting to find out exactly what it means,” he said.
“There are some pretty smart people out there that will assess what Conor’s testing results are saying, but he has had a positive test with negatives around that.”
Victorian Chief Health Officer Brett Sutton said McKenna’s case was not unusual.
“It’s a positive test. It’s being treated as a confirmed positive,” Professor Sutton said on Wednesday.
“There are lots of people who test positive one day, they’re at the very tail-end of their infection and then they test negative the following day.
“If you get two negative tests 24 hours apart, you as a case are clear. But your close contacts, [from] when you are potentially infectious, they have to go through their 14-day quarantine period. That will apply to Conor McKenna’s contacts.”
Professor Cheng said the AFL and public health officials were right to treat the case as a positive result.
“We have done 700,000 tests [in Victoria] and there has been probably less than a dozen of these sorts of cases. It’s unfortunate that it’s happened to him and it obviously has implications for the Essendon football team.”
Professor Cheng said the nasal swab tests, called PCR tests, were reliable and Victorians should place their full trust in the state’s COVID-19 testing processes.
“We only see these sorts of problems emerge when we have such low levels in the community and we are testing so many people. You are starting off from a very low base,” he said.
“In general, if a test is positive, we are pretty confident that it is positive.”
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Hanna Mills Turbet is Consumer Affairs reporter for The Age.