Are we sure these tests have no role to play in the diagnosis of...

Are we sure these tests have no role to play in the diagnosis of people with covid-19, in addition to their other roles? Currently in Australia we are mainly only testing people who have symptoms plus a connection to a source of the virus. Most people who only have symptoms are not tested.

Presumably people with symptoms would be the next cohort that we would want to test if it were possible to do so. If a person has had symptoms for, say, three days, we could presumably make some educated guesses about how long they had been infected for. I believe the Cellmid tests become more accurate at diagnosing the presence of covid the longer the person has been infected for.

Would it therefore be possible to make the finger-prick tests available for people who had been experiencing symptoms for a certain period of time. Although a negative test might not be 100 per cent reliable (no test is) a positive test could identify a person with the virus and they could be quarantined. Under the current testing regime, such a person would not be tested and would not be quarantined. So perhaps these Cellmid tests could play a role in identifying infected people and removing them from circulation.

Does that make sense? I'm not pushing a barrow here, just trying to understand.