So you take a PCR test and it comes back positive. That means you have the flu.
Is it Covid-19 or the good old fashion flu? Can’t tell without further genome testing.
OK, please do that and tell me if it’s covid, what variant it is?
Sorry Hal. I can’t do that. The CDC says you don’t need to know.
You mean, “Sorry Dave. I can’t do that?”
Hal was the computer.
SARS-CoV-2 (the virus that causes COVID-19) is as similar to Influenza virus as humans are to snails. They're both viruses, but that's where the similarity ends. They aren't even in the same phylum. The RT-PCR test for SARS-CoV-2 distinguishes it from all other known viruses, including SARS-CoV-1 and MERS-CoV.
"Is it Covid-19 or the good old fashion flu? Can’t tell without further genome testing."
No, you absolutely can. It is literally impossible for the Influenza virus to trigger an RT-PCR test for SARS-CoV-2. The sequences don't match at all. Not even close. Influenza's genome has about 14,000 base pairs. SARS-CoV-2 has about 29,000. They're completely and totally different.
"OK, please do that and tell me if it’s covid, what variant it is? Sorry Hal. I can’t do that. The CDC says you don’t need to know."
Complete genome sequencing is expensive and time consuming. Roughly $130 per sample. The US has had over 35 million positive cases so far. You want the Federal government handing CDC an additional $5 Billion to satisfy your personal curiosity? Also, it would take months because of the backlog because there aren't enough labs and personnel to keep up. If you want to know which variant you have, find a lab who will take a sample and pay for it out of your own pocket.