But if you are asymptomatic and the viral load is too low to make you infectious then only a lunatic would say a positive test is appropriate.
A lack of symptoms does not automatically mean you are not contagious. In fact, the most contagious period for COVID-19 appears to be before symptoms actually begin (for those who develop symptoms). For the 40% of people who never develop outward facing symptoms, somewhere between 30-50% of them will develop internal damage, particularly in the lungs. This usually heals quickly and isn’t a big deal, but were those individuals ever contagious? That’s an unanswered question right now.
As for this question around viral load, the RT-PCR test is not designed to determine how many virions are present in your body. Thus far, no one has a test capable of doing so without massively expensive and time-consuming study. If you have a test that’s capable of doing so as quickly, cheaply, and accurately as the RT-PCR test is able to identify the presence of SARS-CoV-2 RNA at the site of collection, I urge you to market it immediately. Such a test would be wonderful to have and would make you a billionaire.
So far, nobody else on Earth has managed such a feat. Maybe you’ll be the first. Until then, the best available diagnostic tool we have to determine whether someone is infected with SARS-CoV-2 is the RT-PCR test. It has its limitations (mostly related to the number of infections it actually misses), but it’s the best anyone has managed to come up with so far.
re : But if you are asymptomatic and the viral load is too low to make you infectious then only a lunatic would say a positive test is appropriate.
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You are correct as regards respiratory viruses.
“there is scant, if any, evidence that asymptomatic or presymptomatic individuals play an important role in influenza transmission. “
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2646474/
The near mythical asymptomatic carrier is the result of faulty reporting in the NWJM
https://www.dw.com/en/germany-flawed-coronavirus-study-spread-misinformation/a-52265727
In June even WHO admitted that their ASSUMPTION of equal transmission from symptomatic individuals and asymptomatic individuals was not accurate.