Why have the recommendations changed with the booster dose in Covid? Do we overstimulate the immune system?


There are already more than 10 million Spaniards who have been infected with COVID-19. The pandemic evolves and the health authorities are changing the recommendations against vaccination, so that in many cases we get involved with when and in what situations we should give ourselves the booster dose (the third), more so if we have recently been infected with omicron .

The latest decision adopted by the Public Health Commission, made up of representatives of the Ministry of Health and the autonomous communities, contemplates that the booster dose in the non-vulnerable population and over 18 years of age must be delayed for 5 months if the disease has recently been contracted. COVID-19 infection.

In the opinion of Alfredo Corell, professor of Immunology at the University of Valladolid, this is very good news and for several reasons, as he confesses in an interview with Infosalus. In the first place, he did not know where the recommendation to give an additional dose to the complete regimen 4 weeks after suffering from the infection came from. "It is not conceivable that after 4 weeks of infection you are vaccinated again against the same microorganism. There is no scientific, immunological, or knowledge reason, and we do not know where that initial recommendation came from. Therefore, expanding the booster dose to at least 5 months responds to a necessary and essential change", he adds.

On the other hand, this professor of Immunology values that delaying this booster dose for 5 months still gives time in case any other changes had to be made . "Maybe someone doesn't need more doses, maybe they need it after 8 months, and these 5 months give us enough time to anticipate it," he says.


In his opinion, the pandemic has reached a point and there are so many cases within the population that it is necessary to move on to personalized attention. "There is such a number of different cases that trying to put everyone under the same pattern is wrong . But 5 months, at least, is indicated because it has been seen that stimulation with vaccines, the capacity of antibodies, In addition, it is maintained at that time", he stresses.

Now, it highlights that it is the minimum essential period, but it does not have to be the only one, since there may be people at risk because they are immunocompromised, or because they are very old or with a certain treatment who need that additional dose first, and others, on the other hand, need it, for example, every year. " You have to move on to personalized medicine and at least study antibodies. This will be cheaper than applying vaccines like crazy," insists Corell.


Regarding the alert that some experts are beginning to raise that successive vaccine doses could be overstimulating the immune system, becoming counterproductive, the expert from the University of Valladolid also considers that this should not be done, except in rare cases and with people with a compromised immune system.

" Four doses of the vaccine in a year should not be done because it means overstimulating the immune system , which can cause the opposite effect and it does not respond when the infection arrives. They can be convenient in exceptional situations, in immunocompromised people, but it is that apart, not all vulnerable people are the same. So we return to the same thing, we should see the level of defenses of each one. Personalized medicine is the challenge, doing a personalized follow-up by the pediatrician and the doctor " , highlights Corell.


On the other hand, the professor of Immunology sees it necessary for the authorities to review the COVID passport , since, as he warns, "it is out of date with the current health reality", and many people have recently been infected with omicron, they have done a COVID self-diagnosis, and this is not recognized in the COVID passport; something that, for example, can cause difficulties when traveling abroad.

"I would remove it because measuring the level of protection by the number of doses of the vaccine given is worth nothing if natural infections are not considered. Europe only recognizes PCR, and in Spain these have not been done. So there are millions of people with outdated COVID passports," concludes Corell.