The coronavirus not only spreads to the lungs but throughout the body. Prof. Tobias Huber already demonstrated this in a study in May. In the interview, he explains what other findings were made from autopsies of deceased corona patients and what could work better with a second wave.
That this Coronavirus can lead to loss of smell and taste, for example, is now known. When research autopsied the first corona patients who had died in the spring, however, it was not yet clear that it was SARS-CoV-2 can also spread to organs other than the lungs.
In the meantime, the team led by Prof. Tobias Huber at the University Medical Center Hamburg-Eppendorf (UKE) has published two autopsy studies of deceased corona patients. In an interview with t-online.de, the kidney specialist explains what further studies are planned and what conclusions the scientists draw from the results of the study so far. He also goes into the insights gained in the course of the pandemic have changed and what could go better with a second wave of infections than in spring.
t-online.de: Can you briefly summarize the approach and the results of your studies for our readers?
Prof. Dr. with. Tobias Huber: Essentially, our investigations are autopsy studies. That’s because our forensic specialists in Hamburg probably do the most autopsies in the world Covid-19Patients have performed. Basically every patient who – unfortunately – died in Hamburg from Covid-19 was autopsied, which was able to provide important insights in the fight against Corona. In these deceased patients we have the opportunity to look inside the organs and take organ samples. This is the only way to see which organs are infected by the virus, for example. This cannot be determined in patients who are still alive. What we found is that about 60 percent of those who died have the virus in the kidneys. But also in other organs such as the heart, liver, brain and also in the blood – and of course always in the lungs.
What was the aim of your second study?
In our second study we looked specifically at how the virus in the kidney correlates with possible organ sequelae. We could see that 70 percent of the patients in whom SARS-CoV-2 was detectable in the kidneys had acute kidney failure. In summary, one can say: The result of the first study was that SARS-CoV-2 is not a pure lung virus, but a multi-organ virus that affects many organs. The second study shows what consequences it has when the kidney is infected and that the virus actively reproduces in the tissue.
As you examined in your study, the coronavirus is not a pure respiratory virus. In which organs did you find the most severe damage?
We know first and foremost that the central organ is the lungs. This is the gateway – this is where the virus multiplies, there is the most severe damage, which is also decisive for mortality. In addition, we see that the virus spreads from the lungs to the other organs. What this means for the individual organs – especially in the long-term consequences – is being investigated in studies that are still ongoing. For the kidney, we can at least say that there is a connection with acute kidney failure. In the case of the heart, for example, we can see that there is an increase in myocarditis or sudden cardiac death. In addition, there are many neurological symptoms such as taste disorders, smell disorders, tiredness or difficulty concentrating that could be related to the virus detection in the brain. But here, too, further studies will have to follow.
Prof. Dr. with. Tobias B. Huber
Prof. Tobias Huber is head of the Center for Internal Medicine at the University Medical Center Hamburg-Eppendorf (UKE) and there also director of the III. Medical Clinic and Polyclinic – Nephrology, Rheumatology and Endocrinology. As a leading international kidney expert, he has already conducted two successful studies on autopsies of deceased Covid-19 patients.
Are there any other diseases or viruses in particular that can spread over the entire body in this way?
That’s a really good question. The tropism – i.e. the affinity of a virus for a specific location in the body – is known for many viruses. For example, polioviruses that attack neurons or papillomaviruses or the skin and mucous membranes HIVthat attacks the white immune cells. Many viruses have privileged, special abode in the body. Also about the Influenza you know that the viruses are mainly located in the airways and lungs.
It is also interesting that it was before the new corona virus SARS gave – the virus also had a wide distribution in the body. Why is that so? It essentially depends on how the virus enters the organs and cells. Usually there are receptors that take up the virus in cells. In SARS-CoV-2, this is the so-called ACE-2, a special protein molecule that mediates the uptake in the cells – and this molecule is very widely distributed in the body. It is found in the heart, liver, kidneys, and many other organs. That requires the broad distribution. And by the way, this is not only the case with humans, but across animal species. And that is often not the case with other viral diseases.
According to your study, what influence do previous illnesses have on the course of Covid-19?
Our first study and many other studies out China, Europe or the USA have shown: Previous illnesses have a very significant influence on the severity of the course. These are the main switches for the course. The deceased examined by us had an average of 3.3 serious comorbidities such as Diabetes, high blood pressure, Obesity, lung or kidney disease. This means that previous illnesses play a decisive role. Not whether you get the virus or not – the risk is likely the same for all people. But for the impact the virus has on the body. This is why young, healthy people often have hardly any symptoms.
There has been a lot of discussion about how much life Covid-19 has taken from the deceased patient – what is the current assessment of this question?
In the beginning it was like this: It was noticeable that most of the patients who had died of Covid-19 sometimes had serious previous illnesses. At first this led to the misjudgment that these people would have died quickly anyway if the prognosis was critical. Today we know this better – by looking at large numbers of cases across countries and continents – and statistical calculations now show that many deceased Covid-19 patients have lost a few years of life. You don’t die immediately from diabetes, high blood pressure or being overweight.
For example, one study speaks of an average of eight years of lost life. In fact, with regard to the exact time, one has to say that the comparability of the lifetime of constellations with different previous illnesses with and without corona always depends on some estimated variables. But yes: Covid-19 unfortunately has a significant mortality. And yes: in many patients, the virus unfortunately leads to a significant reduction in lifespan.
What long-term consequences do Covid 19 patients have to expect?
We know the virus can affect many organs – but we don’t yet know what that means in detail. That is why we are building registers and databases. We will only find out the actual consequences over time. The lungs are the most severely affected: Among other things, it remains to be seen to what extent permanent scarring will impair the later functionality and susceptibility of the lungs. For all other organs, no reliable prognoses can yet be drawn unless long-term studies are available. I believe, however, that the long-term effects will mainly apply to severe courses and not to easy courses.
How can damage to organs from SARS-CoV-2 be prevented?
First of all, we should all of course avoid spreading the virus and also get Covid-19 ourselves. Second, we need one to be deployed quickly vaccination and thus the production of a immunity. Third, there are no effective organ-specific ways to contain the spread of the virus in the body. For example, there are therapies under development that are intended to limit the spread of the virus or the severity of the body’s immune response to the virus. These are approaches that are still being explored. But at its core, preventing the virus from spreading and building immunity through vaccination are the best options.
What is the next step with your research – are there any further studies and what further findings are you hoping for?
Yes, there are numerous other studies. One thing that interests us now with regard to the kidney is that there are often changes in the urine as well. That is why we are specifically investigating whether early changes in urine in Covid-19 patients may be a good indicator of the severity of the later course and the likelihood of intensive care. This is a study that is currently ongoing and we are very curious about the results. The other studies that we are doing examine the direct organ damage caused by Covid-19 in more detail.
Apart from your studies: How well is the UKE prepared for a new wave of infections?
Very good. On the one hand, we were able to build very good structures in exchange with national and global expert networks during the first wave and we have all learned a lot in this pandemic. The teams have been trained, processes have been optimized – the interaction between the hospital and resident doctors and all other facilities that care for the sick and those in need of care have also been further developed. We have also set up registers, new communication channels have been created, and we have set up a cross-divisional task force.
There is sufficient capacity for intensive care patients, dialysis, quarantines and normal inpatients. We feel very well armed with all of this, but surprises like this always arise. It is then crucial that the team always creates new solutions and anticipates the challenges through careful observation. Of course, prevention is even better. We want to help prevent the virus from spreading again so quickly, that effective vaccinations are found and that the effects of the virus on the body are lessened.
Thank you for the interview, Prof. Huber.