Dear Dr. Gerstenbluth,

People recently drew my attention to your interview with Dr. Duits. I can understand that immunology and vaccinology is all but your field of expertise. However, if you choose to pick an immunologist to judge my analysis of the current pandemic, you should turn to somebody who really understands what's going on rather than to a doctor who makes a lot of noise but is basically not fit at all when it comes to interpreting the current evolution of the pandemic, especially not when it comes to understanding the immunology involved. Besides the fact that I am left with the impression that the doctor must have Pfizer shares or stock options, I am stunned about his ignorance about the role of natural immunity as a major contributor to herd immunity. One cannot explain otherwise why – despite all current observations – he is still adhering unconditionally to the mantra of mass vaccination during a pandemic! If you take the time to read my scientific analysis of his chitchat, you will appreciate that Duits has a lot to learn. I am offering him a free ride on my website: www.geertvandenbossche.org.

First, how can one be so naïve and ignore that mass vaccination is enhancing fitness of selected immune escape variants? Is it because he doesn't understand virology or vaccines? The simplistic reasoning that vaccinations limit viral replication and hence the emergence of viral mutants doesn't fly at all. It doesn't help to limit viral replication when you cannot completely prevent it as this will enable viral variants to gain a competitive advantage. I was probably the first one to emphasize that variants already circulated before mass vaccination campaigns got rolled out. According to my opinion this has been due to the worldwide implementation of stringent infection prevention measures. Large cohorts of asymptomatically infected people developing suboptimal post-infection titers provide a window of opportunity for (spontaneously emerging) S-mutated viral variants to overcome this immune pressure and adapt to it. By doing so, these variants overcome the pressure placed on their infectivity by infection prevention measures. Putting these variants out in a population in which the vast majority of relevant viral shedders has suboptimal anti-S antibodies (largely due to mass vaccination!) is a recipe for training more infectious variants to adapt and ultimately evolve to become fully resistant to the vaccines.

More scientific arguments countering the non-sense uttered by Dr. Duits follow below. For those who are laymen, it suffices to say that this doctor compares a vaccine with natural infection (except for the nasty side-effects of... the infection!). But he forgets to talk about the lack of parallel between the effect of natural infection and that of vaccines during a pandemic! A natural pandemic is certainly all but comparable to a manipulated pandemic (i.e., a pandemic featured by mass vaccination campaigns combined with stringent infection prevention measures). Mass human interventions have now shaped the course of the pandemic in a way that is completely different from that of a natural pandemic and is already catastrophic in many countries where mass vaccination has been brought up to speed. Duits refers to the figures of Brasil but he's obviously not aware of the figures in Chile, which - in terms of full vaccinations completed - does even better than the UK! I hope he will at least be up for a humble apology when he will soon have to witness what is going to happen in Israel and in the UK (for the latter, several cases of severe disease in fully vaccinated people are increasingly being reported). Hopefully this will be the time or his pride and arrogance to languish as he's considering the case of Israel a proof of 'tremendous' success. If he's so excited about Israel, why isn't he even aware of the vaccination rate in Israel? He states Israel vaccinated over 70% of its population whereas less than 60% and barely 61% are fully or partially vaccinated, respectively.

Dr. Duits pretends that – already naturally – there is a lot of immune pressure placed on the virus since a substantial percentage of the population is naturally protected against the virus. However, he forgets to mention that this protection is not provided by the kind of adaptive immunity he is so excited about but solely by natural immunity. As natural immunity is non-specific, it cannot put selective immune pressure on the virus! What I am, indeed, talking about is vaccine-mediated SELECTIVE immune pressure on the virus' spike (S) protein. In this regard, his reasoning about cross-reactive T cells is another complete nonsense. First, for T cells to be significant in eliminating the virus (i.e., virus-infected cells), they ought to be cytolytic. Such cytotoxic T cells are not elicited at the early stages of infection! They are elicited at a later stage of infection when people who got the disease use such T cells (amongst other immune effector cells) to clear the virus in an attempt to recover from Covid-19. But none of the current Covid-19 vaccines is eliciting CTL responses! On top, CTL vaccines only work in subjects who are naturally predisposed to controlling viral propagation by virtue of their protective MHC cl I alleles. So, you may want to educate Dr Duits a bit in telling him that cytotoxic T cells do NOT have any impact on infection wit Sars-CoV-2 and shedding by asymptomatically infected people (those are the major spreaders when people get massively vaccinated with vaccines that only protect against disease!). On the other hand, CD4 T helper cells elicited by vaccines only assist generation and maturation of S-specific (!) antibodies.

Then, all of a sudden (minute 14:56) , he refers to T cells as being part of innate immunity! He then mentions that S in the vaccine is eliciting many different types of antibodies (Abs) against S protein (polyclonal response) but he doesn't seem to realize that anti-S Abs may bind to the spike protein without having the capacity to neutralize the virus! So, in other words, you may want o educate Dr Duits a bit more and tell him that it is not because Abs bind to S that they will prevent the virus from entering into the receptive target cell! He then confuses Ab waning with the phenomenon I am warning for. Waning is not the problem, but sitting on suboptimal Abs (part of which could be waning Abs) whilst being re-exposed is! (because of potential suppression of natural Abs [Nabs] as explained once again further below)

Dr. Duits's theory about convergent evolution suffers from the same kind of nonsense. Of course, variations of S are converging to the same mutations as all of these countries are now heavily confronted with the same type of huge immune selection pressure on S, as brought about by both INFECTION prevention measures as well as mass vaccination with S-targeting vaccines. The reason I am concentrating on S is because viral variants are OBVIOUSLY selecting mutations that are converging to domains in S that enhance their binding to ACE2 receptor (hence, why they're more infectious!) and because the mechanism of protection of the current vaccines is primarily directed at the receptor-binding domain (RBD) of the virus that is situated - yes! - within the spike (S) protein. Consequently, it suffices for the virus to train S-variants to become more infectious. Because of the resulting increase in viral infectiousness and hence, increase in infectivity rates, the likelihood for a previously asymptomatic person to become re-exposed will now dramatically increases. Many of these previously asymptomatically infected people are sitting on suboptimal Abs that outcompete their NAbs. Consequently, they are now becoming increasingly susceptible to (severe) disease - primarily younger age groups (who are 'naturally' benefiting from a high level of protection due to their elevated levels of Nabs). Dr. Duits should look at the curves in Chile and more recently in India, where vaccination is now up to speed. But clearly, Duits has no clue about natural Abs. As became very clear from his answers to you, he is not even aware of the existence of Nabs. According to Duits, vaccines combine the best of the two worlds, i.e., innate and adaptive immunity. How can one talk such nonsense knowing that vaccine-induced responses are antigen-specific and hence, not properly recognizing mutated S protein, especially not when originating from highly infectious variants?

Furthermore, Duits seems to think that China's CanSino vaccine is a live attenuated vaccine (min 29:00) whereas it's of course an inactivated vaccine. He also believes that the virus will not continue to select mutations for the sake of its own perpetuation but has still not understood that I am not referring to a direct killing effect of those mutations but rather to the increased infectiousness they cause. Because of their higher infectiousness, they increasingly suppress the innate immune system of people who were previously protected (i.e., asymptomatically infected subjects). This doctor also believes that 'as the virus mutates, our immune system will develop more capabilities'! So he seems to believe that the virus exerts evolutionary pressure on its host rather than the other way around. I understand he has no understanding of virology so you may want to educate him on the duration of a Coronavirus replication cycle (which is no longer than 10-12 hours). That is slightly (!) higher than the time needed by humans to replicate. More importantly, it is not clear to me at all what selection pressure the virus would be putting on the human immune system in order for the latter to adapt and develop 'more capabilities'. His statement that the long term effects of the vaccines used in these mass vaccination campaigns are the same as of the infection itself is insane. My concern is that the recall of vaccinal Abs will sustain the mismatch between vaccinal Abs and the altered S protein of highly infectious variants while blocking natural immunity. Duits doesn't seem to realize that this issue does not occur at all upon re-infection after a natural pandemic as a natural pandemic of an acute viral infection does not generate variants (example: Flu pandemic of 1918). Even in the case of antigenic drift or antigenic shift, there is much less of a problem as the vast majority of subjects continue to be protected by their natural immunity (as their Nabs are not blocked in contrast to a situation where these people would have been vaccinated). But how could one have a discussion with someone who doesn't even seem to understand the difference between a pandemic and a seasonal flu outbreak?

Geert Vanden Bossche, PhD, DVM
www.geertvandenbossche.org