Incorrect COVID-19 test and the role played by dead virus cells

In just a few months, research on coronavirus has become abundant as scientists continue to study viral infections and work on developing treatments and vaccines. Ah Review Evidence-based medical centers at Oxford University have shed some light on how effective the tests are in practice.

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standard PCR swab test It’s very sensitive, scientists say, can pick up old viral infections by picking up fragments of dead virus cells. In fact, a person infected with coronavirus is only infectious for about a week, but it can still become positive after a few weeks.

This can lead to inaccurate case numbers, and the current number of positive patients can be overestimated. Professor Karl Hennegan suggested that instead of a positive or negative test result, there should be a cutoff point that indicates the amount of viral load.

Active infection or dead fragment

It does not need to be positive for small amounts of virus, as it does not infect people. Some positive test results are evidence of an old virus and may be the reason for the lack of surge in hospitalization.

In some Covid-19 studies, virus samples were taken and tried to grow in Petri dishes. Virus culture Dead virus fragments are not reproduced in the laboratory environment or in humans, so a positive test can determine if active virus is detected.

A positive test result does not indicate whether the person has a lot of complete and active viral genetic material, or small dead fragments. Those with residual fragments are no longer infected but are still classified as positive.