If you—as a researcher—could do whatever you wanted, what would it be?
Until a few years ago, my answer would have been clearly in favor of biomedicine. It would be fantastic to be able to look inside a body in real time to understand exactly what is happening and what the causes and effects of certain diseases are. In the best-case scenario, we would then also be able to launch targeted interventions that prevent diseases from developing in the first place – a truly fantastic vision. But the question remains: Who would use this technology, and who might potentially misuse it? During my time at the Robert Koch Institute, I dealt with the extensive challenges in the field of public health and realized that the major causes of disease often occur at the population level. To investigate these, it would be necessary and groundbreaking to implement health interventions across entire regions and observe them over the course of years. This would make it possible to conduct long-term research into which factors make people healthy or sick. So: What is the impact of introducing a basic income? Or what happens if we actively take actions against educational inequalities? What truly helps vulnerable groups? Our current healthcare system operates 90% as a reactive system and funds the treatment of diseases rather than their prevention. A preventive system that minimizes the causes of disease would be a revolutionary change. And although the majority of experts know this, it remains a dream.
What is standing in the way of that?
It is ethically and morally unacceptable to observe people as random test subjects and to study social groups over the long periods of time that would be necessary. Under real-world conditions, environments and factors are also not sufficiently separable, and biases cannot be eliminated. Furthermore, in democratic systems, there is high variability due to elections, which would further complicate such long-term studies, as healthcare systems are especially subject to political election cycles.
What research question have you been unable to address so far? And why?
The greatest challenge was certainly during the COVID-19 pandemic, when I was serving in a scientific advisory capacity. My aim was to provide policymakers at the federal level with precise facts, rather than merely statistical possibilities or probable outcomes. It would have been helpful to have even more detailed knowledge in order to give policymakers very clear and well-founded recommendations for the right intervention at the right time. Unfortunately, this will never be completely feasible. Yet even with precise knowledge, political decisions are often influenced by other factors, so that despite sound scientific advice, decisions are made for other reasons.
What once seemed out of reach to you but has since been unraveled?
There have been many advances that once seemed unthinkable. One example from the field of public health is our understanding of the health consequences of smoking: it took decades to conclusively prove that smoking poses health risks – something that is now common knowledge. Similarly, when it comes to environmental pollution, it took several decades to determine which substances in the air, water, and soil pose a health risk. Even with a topic as complex as climate change, which few people fundamentally question today, the causes and consequences are increasingly understood. Of course, many questions remain unanswered here, but progress like this is encouraging.
What are you currently working on as a researcher?
My current project, which is very important to me, aims to combat health inequalities in low- and middle-income countries. These inequalities also exist in Germany, but they are not due to a lack of resources; rather, they are caused by inadequate policy frameworks and misguided incentives within the healthcare system. For example, through a project on child mortality in nine different countries in Africa and Asia, we aim to shed light on the causes and help reduce mortality rates by providing targeted information and developing digital tools. Another exciting project focuses on digital storytelling in health education. We aim to use generative AI to convey information to specific target groups in a way that accommodates their linguistic and educational backgrounds. Generative AI enables us, to an extent previously unimaginable, to meet all people where they are and to expand and consolidate their knowledge. A fundamental vision of our department is to reduce inequalities caused by digitalization.
Prof. Dr. Lothar Wieler has been a Professor of Digital Global Public Health at the Digital Engineering Faculty – a joint initiative of the Hasso Plattner Institute and the University of Potsdam – since 2023.
More information: https://hpi.de/en/wieler/
This article appeared in the university magazine Portal - Eins 2026 „Inklusion“.