Earlier in this thread the thought was expressed players being investigated as viral shedding case was somehow unusual, or even that it was only being done to allow players to play. Rather than it what just was done when it the analysis of the PCR test suggested that it may be a viral shedding case.
So I thought that it might be helpful to share a little more information on this sub-topic.
Note that with blood tests (Serology tests look for antibodies to see if a person has recovered from Covid 19. Because antibody tests do not detect
active viral shedding, they cannot detect if an individual is infectious. The IgG and/or IgM antibodies can provide a clue if the infection was more recent or not. Other lab test can be performed to gain a better idea of whether a person is infectious) that these are not taken initially, but only once there is doubt on the positive result.
Why do some COVID-19 tests come back with a ‘weak positive’, and why does it matter?
In most cases, the genetic material of a virus is only detectable when we’re infected and the virus is still replicating and shedding into our respiratory passages.
But sometimes, even when the virus is no longer alive and replicating, it can hang around and be detectable by PCR. In these cases, it’s unclear whether the virus is infectious.
A man in the Northern Territory recently received a "weak positive" test result for COVID-19. Understanding how coronavirus tests work shows us why this can happen from time to time.
theconversation.com
So if a weak positive is obtained one path that has regularly been gone done in Victoria is to investigate it as a viral shedding case. Not this will have been from the swabs taken for the PCR test and that any blood test will be taken once the decision has been made to proceed further.
and
What’s the difference between viral shedding and reinfection with COVID-19?
It's not only shedding and reinfection which are different — there are actually two types of viral shedding.
theconversation.com
Now with the AO flights, or other people on other international flights, one reason why you would want to know if it was an old or more cent infection is try and gauge if an infectious person had been on the flight or not.