Sucharit Bhakdi, Professor Emeritus of Medical Microbiology at the Johannes Gutenberg University Mainz and a prolific and much-cited expert in his field, has published an open letter to German Chancellor Angela Merkel along with a video addressing some of its contents.
In the letter, dated March 26, Bhakdi poses five questions about the COVID-19 pandemic and the government’s response to it which, he says, “have not been answered sufficiently so far, but which are indispensable for a balanced analysis.”
“As emeritus of the Johannes Gutenberg University in Mainz, and for many years head of the institute for medical microbiology and hygiene there, I feel obliged to critically question the far-reaching restrictions on public life that we are currently undertaking to reduce the spread of the COVID-19 virus,” he begins the letter (which is written in German and unofficially translated below). “It is expressly not my concern to downplay the dangers of the viral disease or to spread a political message. However, I feel it is my duty to make a scientific contribution to correctly classifying the current data situation, putting the facts that we know so far in perspective — and also asking questions that are in danger of being lost in the heated discussion.”
As emeritus of the Johannes Gutenberg University in Mainz and for many years head of the institute for medical microbiology and hygiene there, I feel obliged to critically question the far-reaching restrictions on public life that we are currently undertaking to reduce the spread of the COVID-19 virus.
It is expressly not my concern to downplay the dangers of the viral disease or to spread a political message. However, I feel it is my duty to make a scientific contribution to correctly classifying the current data situation, putting the facts that we know so far in perspective — and also asking questions that are in danger of being lost in the heated discussion.
The main reason for my concern is the truly unforeseeable socio-economic consequences of the drastic containment measures that are currently being used in large parts of Europe, and are already being practiced to a great extent in Germany.
It is my wish to critically — and with the necessary foresight — discuss the advantages and disadvantages of restricting public life and the resulting long-term effects.
There are five questions that have so far been answered inadequately, but are essential for a balanced analysis.
I would like to ask you for a swift opinion and, as it were, appeal to the Federal Government to develop strategies that effectively protect high-risk groups without cutting back on public life across the board and sowing the seeds for an even more intense polarization of society than is already happening.
Prof. em. Dr. med. Sucharit Bhakdi
In the field of infectious diseases — founded by Robert Koch himself — a distinction is traditionally made between infection and illness. A disease requires clinical manifestation.  Therefore, only patients with symptoms such as fever or cough should be included in the statistics as new cases.
In other words, a new infection — as measured by the COVID-19 test – does not necessarily mean that we are dealing with a newly ill patient who needs a hospital bed. However, it is currently assumed that five percent of all infected people become seriously ill and require ventilation. Based on this, projections indicate that the health system could be overburdened.
My question: Did the projections distinguish between symptom-free infected and actual, sick patients — people who develop symptoms?
A number of coronaviruses have been in circulation for a long time – largely unnoticed in the media.  Should it turn out that the COVID-19 virus should not be assigned a significantly higher hazard potential than the already circulating coronaviruses, all countermeasures would obviously be superfluous.
In the internationally recognized journal “International Journal of Antimicrobial Agents,” a work will appear shortly that addresses exactly this question. Preliminary results of the study can already be seen today and lead to the conclusion that the new virus does NOT differ in its dangerousness from traditional coronaviruses. The authors express this in the title of their work, “SARS-CoV-2: Fear versus Data.” 
My question: What is the current occupancy rate in intensive care units with patients with diagnosed COVID-19 compared to other coronavirus infections, and to what extent is this data taken into account in the further decision-making by the federal government? In addition: Has the above study been noted in the previous plans? Of course, the following must also apply here: Diagnosed means that the virus also plays a significant role in the patient’s disease state, and that previous illnesses do not play a major role.
According to a report in the Süddeutsche Zeitung, not even the much-cited Robert Koch Institute knows exactly how much is tested for COVID-19. It is a fact, however, that a rapid increase in the number of cases has recently been observed in Germany as the volume of tests increases.  It is therefore suspected that the virus has already spread unnoticed in the healthy population. This would have two consequences: first, it would mean that the official death rate — on March 26, 2020 there were 206 deaths from around 37,300 infections, or 0.55 percent  — was set too high; and secondly, that it’s hardly possible anymore to prevent spreading in the healthy population.
My question: Has there already been a random sample of the healthy general population to validate the real spread of the virus, or is this planned in a timely manner?
The fear of an increase in the death rate in Germany (currently 0.55 percent) is currently being discussed particularly intensively in the media. Many people worry that they can shoot up, like in Italy (10 percent) and Spain (7 percent), if there is no action in time.
At the same time, the mistake is made worldwide of reporting virus-related deaths as soon as it is determined that the virus was present at death – regardless of other factors. This violates a basic requirement of infectiology: the diagnosis can only be made if it is ensured that an agent has a significant share in the disease or death. The working group of the scientific medical societies expressly writes in its guidelines: “In addition to the cause of death, a causal chain must be specified, with the corresponding basic illness in third place on the death certificate. Occasionally, four-part causal chains must also be given.” 
There is currently no official information as to whether, at least in retrospect, more critical medical file analyses have been undertaken to determine how many deaths are really due to the virus.
My question: Has Germany simply followed the trend towards general suspicions of COVID-19? And: does it intend to continue this categorization uncritically, as in other countries? How should one differentiate between real corona-related deaths and accidental virus presence at the time of death?
The terrifying situation in Italy is repeatedly used as a reference scenario. However, the true role of the virus in this country is completely unclear for many reasons — not only because points 3 and 4 apply here, but also because there are exceptional external factors that make these regions particularly vulnerable.
This includes the increased air pollution in northern Italy. According to WHO estimates, this situation resulted in more than 8,000 additional deaths per year in the 13 largest cities in Italy alone, even without a virus.  The situation has not changed significantly since then. Finally, it has also been shown that air pollution in very young and older people increases the risk of viral lung diseases very strongly. 
In addition, 27.4 percent of the most vulnerable population in this country live with young people, in Spain even 33.5 percent. In Germany it is only seven percent for comparison . In addition, according to Prof. Dr. Reinhard Busse, Head of the Department of Healthcare Management at the TU Berlin, Germany is significantly better equipped than Italy in terms of intensive care units — by a factor of around 2.5 .
My question: What efforts are being made to inform the population about these elementary differences and to make people understand that scenarios such as those in Italy or Spain are not realistic here?
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 Roussel et al. SARS-CoV-2: Fear Versus Data. Int. J. Antimicrob. Agents 2020, 105947
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