Doctors are now recommending a third dose of Covid-19 vaccine for certain categories of the population who are immunocompromised or on dialysis.

Doctor Jimmy Mohamed, health consultant from Europe 1, explains why. 


The recommendation is recent: to be properly protected, some patients, who are more fragile, must receive three doses of the Covid-19 vaccine.

But who exactly is affected?

This is the question asked by Gabriel in

Sans Rendez-vous

, Wednesday on Europe 1. To answer him, Doctor Jimmy Mohamed specifies the contours of this new provision, and the reasons which justify it. 

>> Find all of 

Sans rendez-vous

 every day from 3 p.m. to 4 p.m. on Europe 1 as well as in replay and podcast here

Why a third dose? 

Behind this decision, there are several recent studies.

One of them was carried out in kidney transplant patients who received a dose of Moderna RNA vaccine.

A month later, only 11% of patients had a positive serology, against almost 90% of the average population, suggesting a poorer immune response. 

The same is true with studies of immunocompromised patients, in which only half of people had antibodies after two injections.

This deficit can be linked to the disease as such, which lowers the immune system, but also to immunosuppressive treatments.

Hence the idea of ​​a third dose to "boost" the vaccine in these patients. 

How to benefit from it? 

The list of people who can benefit from this dose can be found on the website of the Ministry of Health.

For the moment, it concerns a limited number of diseases: organ transplant patients, even those who have received a bone marrow transplant, those who are on dialysis, etc. It is then recommended four weeks after the second dose. 


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But beware, this list could evolve and soon concern, in particular, patients with cancer or other forms of immunosuppression.