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02 march 2021
Doctor W. Adlassnig on virus mutations, lockdown, vaccines and herd immunity

Doctor Wolfram Adlassnig, senior biostatistician in commercial drug development, about COVID-19 and related problems


The COVID-19 has greatly shattered our concept about normality and even succeeded to mark a so-called „COVID-Era”. Unpreceded performance for just one year of activity, we must admit, oriented, unfortunately, in opposite directions with our well-being.

This topic dominates the global media and has reached a point of oversaturation. It’s quite difficult to keep up with the updates, and, for this very reason, I intended to gather the latest information and offer some answers to predominant questions on the subject of pandemics.

I am glad that Dr. W. Adlassnig, who is a senior biostatistician in commercial drug development and postdoctoral researcher at the University of Vienna (Core Facility of Cell Imaging and Ultrastructure Research), with professional experience in drug and vaccine development, has agreed to share his expertise and latest research with the Moldovan public. We continue living in the COVID-19 paradigm, so we’d better stay informed. Let’s get to the point!



Dear Dr. Adlassnig, I will spare your time and address the first question straight away: could you, please, explain, in an accesible way, what are virus mutations? Everyone is concerned with the new strains identified in the UK, South Africa and Brazil.

If a virus enters a cell, it forces the cell to produce copies of itself. These copies of the virus are far from being perfect, actually, they are rather prone to error, and these erroneous copies are called mutants. Most mutants are just damaged versions of the original version and not able to infect other cells, but an incredibly small percentage of these errors are actually improvements. These improved mutants may be able to infect cells more efficiently, to survive for a longer time period outside the human body or to escape the immune systems in a more efficient way. Thus, the constant emergence of new mutants is a natural process and was to be expected. The typical trend would be that the virus becomes easier to transmit but less damaging to the host, following the motto „treat your host nicely, you only got this single one“. Still, there may be exceptions to this trend, and some mutants may be more damaging than the original version. I would also expect new mutants which are able to overcome the protective effect of today’s vaccines. Thus, the vaccination programs can only be successful if we are able to develop new vaccines faster than the virus develops new mutants.

What about the new strains of COVID-19? I’ve read that they tend to be more contagious and I can also remember that B. Johnson claimed, back in January, that the UK strain “can be more deadly”. Is there any data to support this claim?

Evolution towards more contagious strands is exactly what was to be expected - obviously, a more contagious mutant will be more successful and can outcompete less contagious strands. Concerning death rates, I would be very careful. Death rates are generally low and depend on many parameters, so it is really difficult to find statistically significant correlations. However, hospitalization rates for the British mutant were indeed higher both in the UK and in Denmark. Furthermore, the British mutant is mutating at an unusual speed, rapidly producing more mutants, some of which may be more dangerous.

The UK strain pervaded the whole Europe and is already dominant in the big cities of Romania, so it would be rational to assume that it’s present in Moldova as well. More than that, because of a considerable increase in infection cases, a special regime will be imposed in the RM, starting with the 1st of March. Schools and other public and private institutions will be closed for the next 2 weeks. How effective are these measures in decreasing infection rates? What does the data say?

The epidemiologist John Ioannidis from Stanford compared of lockdown measures throughout the world, and his findings are pretty clear and consistent with other research: A „soft lockdown“, i.e., closing festivals and other mass events, has a significant impact on infections. A „hard lockdown“, as planned for Moldova, has more or less the same impact as a soft lockdown. Thus, hard lockdowns offer little benefit but cause tremendous collateral damage. For example, the US states North and South Dakota have very similar infection rates, though North Dakota is far more strict than South Dakota.

Would you suggest that opening schools, in such dangerous times, will not expose children to the risk of being infected, transmiting the virus to their grandparents...? The consequences could be irreversible...

Several studies have shown that transmission in schools is rare. If basic social distancing is maintained, infection rates among teachers are even lower than in the general population. Furthermore, preventing children from getting proper education will severely affect their future lives and has also an impact on society and economy. Yes, there may be some risk for grandparents who share the same household or are already sick. But individual families are surely able to implement appropriate safety measures for their specific situation, which are more efficient than a nation-wide closure of schools.

In the RM the following vaccines have already been authorized: Sputnik-V, Pfizer/ BioNTech and AstraZeneca.  Is there any comparative research about their efficiency in general and on new COVID-19 strains, in particular?

For all three vaccines, studies have been conducted which indicate that they are safe and effective, at least for preventing infection in general. Little is known about long-term safety, or if any of the vaccines can prevent death or hospitalisation. At present, it seems as if Sputnik-V and Pfizer/BioNTech were superior to AstraZeneca, both with regard to safety and efficacy. Concerning new mutants, I expect all three vaccines to become ineffective in the foreseeable future, so they have to be constantly modified in order to keep step with the mutations. In the Pfizer/BioNTech vaccine, such modifications should be rather easy, so this vaccine may have the greatest potential.

However, I noticed that people are very skeptical about the Sputnik vaccine, considering that it is still not approved by the European Medicines Agency…

All vaccines were authorised before a proper safety assessment had been completed, as it is standard for other vaccines. So far, the Gamaleya Institute (that developed Sputnik V) has not even applied for authorisation in the EU, so we do not know if EMA would authorise Sputnik-V. Possibly, the Gamaleya Institute wants to avoid inspections by the EMA, which are part of the authorisation process. Medical data do not support specific skepticism about Sputnik V. Concerning possible modifications, the Pfizer vaccine is based on molecule called RNA, which can be modified extremely easily. Sputnik V is based on a kind of artificial viruses, here, the whole system has to be changed.

I would also like to touch the subject of herd immunity. Considering that Moldova is such a small country with only 2, 6 mil of inhabitants, can we expect to achieve a herd immunity more easily? To this date (28.02.21), the official total number of cases has reached the number of 185 000.

Covid comes in waves. So far, each wave has stopped long before herd immunity was even close, only to be followed by another wave a few months later - the reasons are poorly understood. Herd immunity would require at least 60% of the population to be infected. If the virus spreads at a constant speed, herd immunity in Moldova would be achieved only in 2028, even without considering mutations. Furthermore, it is unlikely that people would stay immune for such a long time after infection. Thus, aiming at herd immunity is probably as ineffective as a hard lockdown.

Future perspectives do not seem too bright: herd immunity is not a viable option, the long-term effects of vaccines are unexplored and their current effectiveness might be affected by continuous mutations. As a researcher, what “middle way” do you see, so that we do not barricade ourselves in our cells, while also protecting collective health?

The virus will not disappear again, and we have to accept the fact that some lives will end prematurely. However, I am rather optimistic that we can mitigate the effects of the pandemic by combining all available strategies in an undogmatic fashion. In addition to the strategies we talked about, we should try to increase ICU capacities, make testing available for everybody and optimise treatment of the infection - there has been no decisive breakthrough, but multiple small improvements. Finally, everybody can improve his own immune system by living a healthy and active life.

Dr. Adlassnig, thank you very much for clarifying these aspects! I believe that your answers covered most important points and, hopefully, will help our public lead their lives, instead of being led by fear.




Mihaela Dima

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