Targeted testing for COVID-19 infection is one of the most effective means of responding meaningfully to the current pandemic. However, at very high incidence rates, existing testing capacities reach their limits. This is precisely where the “Where2Test” platform come in. Where2Test is being developed by researchers at the Center for Advanced Systems Understanding (CASUS) of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and is funded by the Free State of Saxony to the tune of one million euros. The project has just reached an imporant milestone: the prototype went online on February 1, 2021.

With the platform, the Görlitz scientists want to identify ways to efficiently and specifically use the existing COVID-19 testing capacity, to create the most comprehensive overall picture of the situation as possible. In the future, it should provide answers to important questions: Which groups need to be tested? What types of tests should be used? Where, at what time, and how frequently must testing be done? “The published platform is a very first prototype that will initially only provide well tested basic functions, such as the spatial representation of the collected data,” says project leader Prof. Justin Calabrese, describing the current status. “In a continuous development process, we now want to integrate further functions that can offer valuable contributions to overcoming the pandemic.”

Originally planned for Saxony only, the long-term goal of the platform is to manage the use of existing testing capacity in such a way that infection events can be precisely tracked. To achieve this, the CASUS scientists want to collect current data on testing capacities and infection figures with Where2Test, in order to subsequently be able to develop optimal testing strategies on a daily basis at the county level. This will require the use of data science methods and extensive, detailed simulations of epidemiological dynamics with high spatial and temporal resolution. To facilitate this, the CASUS researchers will use high-performance computing resources such as the HEMERA cluster at the HZDR. Overall, the project could make an important contribution to limiting the spread of this and future pandemics, as Saxony’s Minister of Science, Sebastian Gemkow, emphasizes.

“The Free State is supporting Corona research at universities and non-university institutions in Saxony with a total of around 16 million euros. I am pleased that the prototype of Where2Test is now going online and wish this CASUS project every success. Where2Test is intended to enable a rapid assessment of the current situation, and concrete recommendations for action can be made promptly in each case for policymakers and the healthcare system. This digital solution to best use testing can become an important part of a strategy to contain not only COVID-19. The Corona pandemic and potentially future pandemics, as this project also makes clear, can only be managed together, across disciplines and across country and state borders.”

The Scientific Director of the HZDR, Prof. Sebastian M. Schmidt, also emphasizes international cooperation as a contribution to overcoming the pandemic: “CASUS is a prime example of interdisciplinary research. Here, the strengths of the TU Dresden, the Leipzig Helmholtz Centre for Environmental Research, the Max Planck Institute for Molecular Cell Biology and Genetics, the University of Wroclaw and the HZDR are bundled. Researchers from around the world are working together in Görlitz on novel digital methods to better understand complex, interconnected systems. The Corona pandemic – as well as all other pressing questions of our time – shows us that we can only find suitable answers through this interplay of different research areas. We are pleased that we can now also contribute to the fight against the Corona virus with the Where2Test platform.”

The international team led by project leader Calabrese and project coordinator Dr. Weronika Schlechte-Wełnicz plans to take into account influences such as the current lockdown, seasonal effects or, in the future, vaccination rates as they continue to develop the platform. However, the platform could also integrate data from other German states as well as beyond, as Schlechte-Wełnicz explains, “We were already able to include data on infection figures and testing capacities from the Czech Republic during the set-up phase. This enables us to check the predictions of the epidemiological models against a larger data set and thus continuously improve them.”

For example, in an international collaboration between the University of Maryland in the United States and CASUS, the scientists plan to investigate how testing of patients with and without symptoms needs to be optimized depending on the number of infections when only a certain number of tests are available.

Where2Test can be accessed online at www.where2test.de.


CASUS was founded 2019 in Görlitz/Germany and pursues data-intensive interdisciplinary systems research in such diverse disciplines as earth system research, systems biology or materials research. The goal of CASUS is to create digital images of complex systems of unprecedented fidelity to reality with innovative methods from mathematics, theoretical systems research, simulations as well as data and computer science to give answers to urgent societal questions. Partners are the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), the Helmholtz Centre for Environmental Research in Leipzig (UFZ), the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden (MPI-CBG), the Technical University of Dresden (TUD) and the University of Wrocław. CASUS is funded by the Federal Ministry of Education and Research (BMBF) and the Saxon State Ministry for Science, Culture and Tourism.