Can a pcr test diagnose both COVID-19 and Influenza? Yes!
Recently an announcement by the CDC, withdrawing a SARS-CoV-2 pcr test for EUA FDA approval, has been spreading on the internet like wildfire with a very significant misinterpretation! People are saying that the withdrawal was because it could not differentiate between COVID-19 and the Flu… this is not the case at all! So what did happen?
• Most COVID-19 PCR tests ONLY detects SARS-CoV-2.
• Recently PCR tests that detect BOTH SARS-CoV-2 AND Influenza are becoming more widespread and available.
• The CDC wants to focus on using this combination test! This is why they are no longer interested in moving forward with the single test.
Why is this exciting?? It is a better diagnostic tool! If you feel symptoms of the flu or COVID-19 and go in for a pcr test, your will results will give you a “positive” or “negative” readout for BOTH of these viral infections. Quick, easy, and much more efficient.
So let’s not confuse this message. PCR is very sequence specific, meaning it can be designed to ensure that only one particular viral genome is detected. The COVID-19 PCR tests could absolutely differentiate between SARS-CoV-2 and Influenza. The new update is making it so the PCR can tell you about BOTH!
Let’s get more technical:
PCR includes oligonucleotide primers that are designed to bind to a very specific sequence in the target DNA. In the presence of an enzyme (Polymerase), these primers are able to identify and bind to their target DNA and amplify it exponentially. If there is no signal, their was nothing in the sample that matched your target. If you include primer sets for multiple targets – a set of primers for SARS-CoV-2 and a set of primers for Influenza – this is called multiplexing! Each amplfied target can be read separately.