With total humility I am forwarding you what others say…..this is totally beyond my understanding!

However, PCR still has its caveats. These types of Covid-19 test need to be sent away to a laboratory for analysis, meaning it can take days for people to find out their results.

False negatives can occur up to 30% of the time with different PCR tests, meaning they’re more useful for confirming the presence of an infection than giving a patient the all-clear. They can also provide false positive results, as they’re so sensitive they can potentially signal a positive result upon detecting dead, deactivated virus still present in the body of someone who has recovered from Covid-19.

Warwick Medical School honorary clinical lecturer Dr James Gill said: “During the course of the outbreak, the PCR testing has been refined from the initial testing procedures and with the addition of greater automation to reduce errors. As we are looking at swabs taken from people, who have lots of other organisms floating around, we are essentially dealing with the question of how ‘right’ the result we are looking at is.”

The only thing I learn from this,is that a positive test means that there has been a covid-19 infection [detecting dead, deactivated virus still present] or that there is indeed an active infection.

This…….until it may be discovered that there are cross-reactions between this covid test and totally other diseases, but this will be then likely in rare cases.

This is not fantasy but has been shown in medicine already not a single time.

https://gh.bmj.com/content/4/4/e001582

https://www.bmj.com/content/373/bmj.n1411/rr

False-positive IgM results for measles may be due to the presence of rheumatoid factor in serum specimens. Serum specimens from patients with other rash illness, such as parvovirus B19, rubella, and roseola, have been observed to yield false-positive reactions in some IgM tests for measles.