WHO Director-General, Tedros Adhanom Ghebreyesus
Big Pharma pushes for the third dose of Coronavirus vaccine to be considered essential to seniors next year but the answer, at the moment, lies only in the behavior of people in Indonesia, in greater Jakarta (over 30 million people) and also in the populous area of the Nile Delta where over 40 million are concentrated, or in Brazil and South Africa.
In fact, it is in these areas that the virus, through inappropriate “modus vivendi” among people who are not even immunized, can raise the level of mutations that make the virus live.
In this case, a third dose would be needed to avoid other waves of contagions in the world.
Many health professionals agree that the third dose will only be needed in two cases. The first, the least likely, could happen if the vaccinated were reinfected because their defenses lost their immune memory.
The second, the most likely, would be the variant of a new mutated strain, and a lot, compared to the current variants that would render vaccines ineffective. In this case you would be in the same condition as annual flu with a new strain and a new vaccine.
Obviously the big producers are pushing for the third dose. Ugur Sahin, one of the founders of BioNTech, the pharmaceutical company that invented the vaccine marketed by Pfizer, argued that the third dose will be needed between nine months and a year after the first cycle.
The reason would be given by the decrease in antibodies. A thesis also supported by the CEO of Moderna, Stéphane Bancel.
The scientific community, however, is accepting these suggestions with caution and has asked companies to make public any studies that would support this thesis.
For its part, the same scientific community has stated that, currently, the third dose will not be necessary since the immune response obtained with current vaccines is sufficient against all known variants.
Experts recall that the immune system, one of the most complex in man, defends itself against pathogens on several levels. For example, the body runs out of antibodies to hepatitis B years after the vaccine, but cellular memory maintains the ability to produce them if necessary.
Many virologists confirm that if no new strains emerge, the third dose will not be necessary, the immune response will be sufficient. There are studies that reveal that people infected with the first SARS, in 2002, can produce effective antibodies and at all ages.
Another issue is to know whether the vaccine response will be sufficient even against the new mutations. The answer is almost mathematical and lies in the logic of probabilities. If the virus replicates trillions of times a day in hundreds of millions of infected people, it is foreseeable that in the end the vaccine will no longer defend.
Some experts note that the virus has a history of mutations somewhat, almost like the flu virus and its genome has 30,000 nucleotides and in each cycle of reproduction 1 in 10,000 changes. Each time it replicates, therefore, the virus undergoes three changes and this can significantly alter its infectious capabilities. It may be possible that, every year or two, vaccines need to be adapted to the variants or strains circulating at the time.
In short, the secret to win back the virus is always to rapidly distribute vaccines to immunize the entire world population. With far fewer people at risk of contracting the virus and most vaccinated, those who become infected will have low viral loads and mild problems.
This way the pandemic will control itself. Unfortunately, the strategy used up to now, namely the rush of rich countries to monopolize the doses in this first phase of the pandemic, has left large areas of the globe behind in the vaccination campaign. This has led to dangerous variants in less protected areas such as India, South Africa and Brazil.
The greatest risk would be an endless cycle in which poor vaccination in some parts of the globe would allow the emergence of new strains against which rich countries would rush to vaccinate first.
The only solution, politically impossible to implement, would be to place all responsibility for distribution in the hands of the WHO.