ICYMI: False negatives in diagnostic testing of COVID-19

A new study highlights the inherent risks in the over-reliance on current COVID-19 testing to make clinical or public health decisions.

Currently, reverse transcriptase-polymerase chain reaction test (RT-PCR) is one of the most widely used tests to detect SARS-CoV-2, which has now been found to have a high chance of providing false negative results.

In the four days before the typical time of symptom onset, the probability of a false negative result in an infected person is 100% on day 1 and 67% on day 4. This clearly shows the need for caution when interpreting RT-PCR tests for SARS-CoV-2, particularly early in infection course.

As research into COVID-19 is still evolving we need a greater understanding of testing efficacy, but this poses some interesting questions. 

Could this mean the death rate recorded is even lower than currently thought? How does COVID-19 then compare to the flu?

What do you think?

Since this research was released, COVID-19 has albeit disappeared [from our media at least?]. Perhaps this also means that we no longer need a vaccine?

Even though COVID-19 almost feels like a thing of the past, keep supporting your immune system with recipes like our Zesty Garlic Dressing here.


Kucirka LM et al., 2020. Variation in False-Negative Rate of Reverse Transcriptase Polymerase Chain Reaction–Based SARS-CoV-2 Tests by Time Since Exposure. Annals of Internal Medicine.

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