This is a good remark. Covid19 is detected using so called q(quantitative)PCR or Real-Time PCR. This indeed requires real time fluorescence detection as the the

This is a good remark. Covid19 is detected using so called q(quantitative)PCR or Real-Time PCR. This indeed requires real time fluorescence detection as the thermal cycle at which your signal starts to ramp up is a measure for the amount of DNA or RNA molecules present in the original sample.