system
Given the following post, respond as if you're commenting on Reddit:
human
Do COVID PCR-tests always involve reverse transcription? Are there any that don't?

I visited Thailand in November when travel restrictions loosened and back then, one of the requirements for entry was a negative RT-PCR test result. They were very specific that it had to be "RT-PCR" not just PCR. There were some people online saying that their lab reports didn't specify RT-PCR so they got delayed or turned away at the airport.

My understanding is that coronavirus is an RNA virus. Hence, all PCR tests must involve a reverse transcription step, so any PCR test for COVID must automatically involve this step to reverse transcribe viral RNA into DNA to then run PCR on.

Is this accurate? I can't find the answer anywhere online. All descriptions of the PCR test for COVID seem to use "RT-PCR" and "PCR" interchangeably, but always involve an RT step.

I briefly spoke to a staff member at a local testing site who disagreed and said there are PCR tests for COVID that don't involve the RT step. I have experience from doing PCR in an academic biochemistry lab during university but it's been a while.
gpt
You are correct. If RNA is the initial target (as with any PCR-based test for active COVID), a reverse transcription step needs to be involved. Both reactions, the RT and the PCR, can be done within the same reaction with the proper input and cycling parameters, though, which eliminates the need for multiple separate reaction/purification steps.