Third dose of vaccine for the immunosuppressed. What do we know about the Italian decision

Here we are. On the third dose of vaccine the decision must only be formalized. It’s especially about people immunodepresse, «Who have a weaker response» and for which it is considered appropriate «a booster 6-7 months after the completion of the vaccination cycle». Word of Silvio Brusaferro, president of the Higher Institute of Health, who in an interview with Press has outlined a path that would seem to essentially align with the German government’s plans: Germany will offer the elderly and people at risk a third dose of the anti-Covid vaccine starting in September.

It will be a further recall with Pfizer or Moderna also for those who have already received two doses of Astrazeneca or the single from Johnson & Johnson. Not only that: the ministers of health of the 16 Laender have finally decided to offer the doses to children aged 12 to 17 years. The same path that the British executive is about to take: third administration from next month for the elderly, the chronically ill, subject to risk of respiratory infection.

On the need for the third dose of vaccine for the rest of the population, “for now we know that the immune response goes beyond six months, new studies say more than eight. But they are being updated. For this reason today we cannot yet say if and when it will be necessary »added Brusaferro. Which therefore, on the third dose, traced a scenario similar to that of anti-influenza vaccinations, presumably manageable by the general practitioner network, dismantling all or most of the maxi vaccine structures currently in operation.

“To avoid a fourth wave we have two tools at our disposal and both of them must be used: those of the vaccination and gods right behaviors that depends only on us to adopt. In terms of vaccinations, I am pleased to see that young people are responding well, as evidenced by the strong growth of immunized people between 20 and 29 years old, ”explained the president of the ISS and spokesman for the CTS. Which also recalls the pitfalls of the so-called long Covid, the persistence of symptoms of various kinds and the reduction of the functionality of some organs even for many weeks after the negativization in those who have had the infection at each stage, with percentages ranging from 2 to 13% of the infected.

In Israel, Pfizer’s laboratory country, the administration of the third dose of the vaccine has started to those over 60 who have received the second dose for at least five months (the threshold should be that, more or less five or six months from the end of the first cycle. vaccinal). According to the data released in preprint by the same US giant, the third dose would induce “titers of neutralizing antibodies against the Delta variant more than five times higher in younger people and over 11 times greater in elderly people than two doses ». In the coming weeks, these data will be shared with the regulatory agencies, on all Fda (which in September will provide the final approval of the vaccine) and EMA. For Pfizer, the vaccine would lose some of its effectiveness within six months, dropping from 96 to 84%, losing about 6% every two months after completing the cycle. Moderna would remain 90% effective against symptomatic Covid-19 and 95% effective against severe disease after six months, the group explained last April, while Johnson & Johnson did not show efficacy at six months.

For this reason, the European Commission – on which centralized purchases of vaccines depend – explained that it was “aware of the fact that a third dose may be required” and that it has “entered into a third contract with Pfizer-BioNTech, which books 1.8 billion doses“. Stocks that could also be used for “the fight against variants or if we had to vaccinate other groups, such as young people and children”. Even with Moderna they have been optioned another 150 million doses for the second contract. «In the meantime we continue to follow the situation with the EMA. As always, the decisions we make will be based on science ». The road therefore seems to be that of relying definitively, at least in Europe, on mRna vaccines. Even if, for example, just in June a study by the University of Oxford is about to be published on Lancet explained that a third dose of the AstraZeneca vaccine “given at least six months after the second, he.” increased antibody levels sixfold and maintained T-cell response. A third dose also determined a greater neutralizing activity against the Alpha, Beta and Delta variants ». According to the results in the preprint, among other things, “both the second and third doses caused fewer adverse reactions than the first”. We should also reflect for a long time on the desirability of giving up a safe, cheap and apparently effective vaccine altogether.

At the beginning of July Pfizer and Moderna finally announced that they had one in the pipeline updated version of the vaccine against the coronavirus able to block the Delta variant even more efficiently (and any others that may cause concern, such as the lambda variant widespread in thirty countries, particularly in South America, on which alarming studies are beginning to emerge). It is difficult to understand if the first phase of the third doses of next autumn will be based on vaccines such as those used so far or already, if the further clinical trials will be concluded, on the updated product.