The recent Echo article ‘How reliable are PCR tests?’ (8 September) on PCR tests for COVID-19 that refutes the proliferating doubts on social media regarding their accuracy is to be praised in its intention of countering misinformation – so easily propagated in our virtually warming climate of swarming memes.
However, the authors used examples employing electrophoresis gels to detect PCR (polymerase chain reaction) amplification products (‘traditional PCR’) from samples containing the SARS-Cov2 virus. Yet, these are not used as a detection method in any Australian approved/certified nucleic acid-based commercial PCR test for COVID-19.
Such approved tests (called real-time reverse transcriptase PCR or RT-PCR) do indeed depend on PCR reactions, but amplified viral gene signals are detected as the amplification occurs, not after it, as in the bands of the article’s gel-based method, by using a fluorescent dye which binds to amplified DNA or is incorporated into such DNA during the reaction.
The Cosmos article reproduced may have used the gel-assessed PCR and images to simplify PCR results for public consumption, but does not convey appreciation of state-of-the-art technology actually used in PCR testing for SARS-Cov2.