In "Sans Rendez-vous", Doctor Jimmy Mohamed responds to Mathilde, a listener who wonders why certain PCR tests are still positive several weeks after being ill.

The specialist explains that this happens when some patients keep non-contagious traces of the virus in their body.

Why are some PCR tests still positive long after contamination?

This is the question asked by Mathilde, a listener who seems to have an acquaintance who contracted the coronavirus.

In "No Appointment", doctor Jimmy Mohamed reassures her by explaining that a positive test does not necessarily mean that the person is contagious.

This is why health authorities recommend isolation for 7 to 10 days after infection with the coronavirus.

But the specialist also details the puzzle of the positivity of the tests generated by the arrival of the variants. 

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Coronavirus: follow the evolution of the situation Thursday March 4

A positive PCR does not necessarily mean that you are contagious

"It all depends on the patients: some will indeed keep a small excretion of the virus in their body. And detection techniques via the PCR test are so efficient that they detect them, even though these traces are no longer contagious. This is why it is now useless to do a control test after a first positive PCR with the historical strain On the one hand, we do not know what to do with this information, and above all it does not prove your contagion. 

But the appearance of Covid variants has completely changed the situation, to the point of becoming a real headache.

Because the recommendations change every four mornings.

If, for example, you do a PCR which turns out to be positive for the Brazilian or South African variant, you must do a control test between 7 and 10 days later to be sure that you are no longer contagious and that the isolation is lifted.

On the other hand, we do not do this control test with the British variant.

It is therefore a very complex situation, including for doctors.  

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The rant over long Covid

In addition, long Covid patients are no longer contagious after a month, even though they may have symptoms, such as severe fatigue for example.

There may be mechanisms in this phenomenon that we do not yet understand. 

But what must be understood with long Covid is that we are creating 10% to 15% of long Covid in healthy 30-year-olds who will have symptoms for a very long time. .

At the current rate of the epidemic, thousands of people are therefore becoming chronically ill with general indifference.

This is also why we must limit the epidemic as much as possible.

Covid is not a trivial disease, and having only two or three days of fever does not prevent you from having symptoms several weeks later. "