The fourth year of the corona pandemic has begun. Giessen infectiologist Susanne Herold talks about the virus in an interview.
Gießen – The fourth Corona year has begun. The number of infections is declining, experts see us on the way to endemics. Also Giessen infectiologist Susanne Herold assumes that the virus will continue to occupy us seasonally. In an interview, she explains how the situation at the university clinic Pour is what multiple infections mean for the immune system and how vaccination against Corona could be done in the future.
Professor Herold, we are entering the fourth Corona year. The Minister of Health of Baden-Württemberg, Manne Lucha, commented on this with the words “We are no longer driven.” How do you see it from the point of view of an infectiologist?
Susanne Herold: At the moment we are noticing that the winter wave is decreasing and the number of infections is falling significantly. Overall, you can see that we are gradually entering the endemic phase.
Why is that?
From a global perspective – with the possible exception of China – we now have a good level of immunity among the population. The virus can no longer affect us as it did from the first to the third wave. We would not have achieved this without vaccination. Almost everyone in this country has now had contact with the virus or its most important antigen, the spike protein – be it through several vaccinations, often in combination with a previous infection, or rarely just through infection. As a result, the virus has been pushed into a corner, so to speak, when you look at its co-evolution with humans.
Will mutations continue?
Yes, it will, mainly due to new immune escape mutations in the spike protein, which is the part of the virus surface that our antibodies recognize. For example, we are currently seeing that in different parts of the world Omicron and BA5 are being replaced by other variants that are even better able to evade our immune response. This reduces the ability of our antibodies to recognize such viruses. At the same time, however, we still have the second arm of the immune system, the T-cell immunity, and it is hardly affected. The more antigen contacts we had, be it through vaccination or through infection, the better the overall result will be, and the fewer immune escape variants that can lead to serious infections. Ultimately, this will lead to the virus becoming seasonal or endemic. We will have corona infections in winter, and occasionally see more severe infections, because the antibody titers will fall again over time. This is particularly true for risk groups and for those people whose immune system cannot build up good protection due to certain diseases.
This also means that the high mortality rate seen at the beginning of the pandemic is over.
Yes, we will no longer have to live with the high mortality and the enormously high disease burden of the first waves, but we will still have to live with a certain disease burden in winter – similar to, for example, the viral flu. But it is still important to protect the risk groups well. To do this, we now need good vaccination concepts for risk groups in this transitional phase to the endemic. Another important factor is: We know that as a risk patient you can protect yourself well with FFP2 masks in the winter season. This also applies to other pathogens of respiratory diseases such as the influenza or RS virus. We should now take this knowledge gain with us for the future.
You mention wearing a mask. The mask requirement is falling everywhere at the moment, even medical representatives are talking about abolishing them in the practices.
It certainly makes sense that the legally prescribed mask requirement is lifted in many areas. Because most people can no longer get so seriously ill. After all, a mask requirement must always be in a certain proportion. In the practices, every doctor can decide for himself. For example, anyone who treats many immunosuppressed patients would make sense to ask them to wear masks in the winter months. At the same time, anyone who is at known risk can now protect themselves.
Interview with Giessen infectiologist Susanne Herold: »The difficult time is over«
What will the Covid vaccination look like in the future – and who will receive it?
There will probably be a vaccination recommendation for risk patients. The question is: at what frequency should one vaccinate? And: Will specifically adapted vaccines be recommended – as with influenza? This is highly relevant for influenza, because we know that annual mutations clearly occur there. However, I doubt whether we will constantly need newly adapted mRNA vaccines against the corona virus. The aim of the current research would be a joint vaccination against Covid, influenza and possibly also against RSV infections, which would then ideally not have to be administered annually, but at longer intervals. Such combination vaccines have now become more feasible thanks to mRNA technology. At the same time, we know that the immune memory of the mucous membranes can be activated much better with local vaccinations, for example administered with nasal sprays. Current research strategies focus on heterologous combination vaccinations that target both the systemic immune memory through vaccination in the muscle and the local immune memory of the respiratory tract.
What is the corona situation in Gießen University Hospital?
The hard time is over. We still treat corona patients, the number is usually between 20 and 40 inpatients. But in principle, with a few exceptions, the severity of the disease is significantly lower, and many patients come to us with a positive corona test as a secondary diagnosis and not because of Covid.
Federal Health Minister Karl Lauterbach said in an interview that multiple infections with corona could result in an immune deficiency that could no longer be cured. He later rowed back. As an infectiologist, what can you say about this thesis?
I was amazed at the statement. There is certainly very good research data showing that this infection, as well as other infections, can affect various functions of the immune system over the longer term. These include so-called epigenetic changes that leave a signature similar to that of aging, or the “accidental” formation of autoantibodies. My working group also collected such data in an international project. However, we see that this also happens with other infectious diseases of the lungs.
So the topic needs to be defined more clearly?
Yes absolutely. It is a whole complex of topics related to the molecular mechanisms of the long-term effects of acute respiratory infections. The intensive international research activity in the context of the pandemic has brought to light many new aspects of infectious diseases, most of which are not limited to SARS-CoV-2 infections. We have also seen with influenza, for example, that infectious diseases have an impact on metabolic functions and aging processes or can promote strokes and heart attacks. Now we need to get closer to the molecular keys. This is currently being increasingly promoted in large collaborative research networks, also in infection and lung research in Giessen. It is an interesting, important field of research that is opening up here. But we’re just getting started, and there’s currently no evidence to support such a broad statement about immune aging.
What you describe clearly shows once again the importance of basic research at a university hospital, where research, teaching and treatment are carried out.
Exactly. It will be crucial that we take up exactly this in large research consortia such as the Cluster of Excellence “Cardio-Pulmonary System”, but also in our collaborative research centers and within the framework of the German Center for Lung Research and the German Center for Infection Research. We have to use the entire range that is available at the university hospitals: from molecular mechanisms to new therapies for patients, from basic research to application. Especially at the UKGM, where the focus of research and treatment is on infectious and lung diseases.
The interview was conducted by Kays Al-Khanak.