“CovApp can be used whenever someone thinks they may have become infected with the novel coronavirus,” explains Dr. Alexander Thieme, who programmed the first iteration of the app and was project manager in the development of the updated version. “It includes questions about such things as symptoms, high-risk contacts, chronic diseases, and test results. We have gradually gained more and more knowledge about the coronavirus, and we wanted to provide users with personalized recommendations for action based on the latest research.” Thieme is a physician in the Department of Radiation Oncology and Radiotherapy at Charité – Universitätsmedizin Berlin, a fellow and spokesperson of the Biomedical Innovation Academy’s Digital Clinician Scientist Program of the Berlin Institute of Health (BIH) at Charité, and currently a visiting scholar at Stanford University in California. “Based on the answers it receives, CovApp determines the user’s clinical situation and suggests possible next steps,” explains Thieme.
CovApp is thereby capable of assessing a variety of different situations – such as a vaccinated person who has still become infected, or a potentially incorrect rapid antigen test result. The app is also able to gauge the likelihood of the symptoms becoming severe or of the virus spreading to others in the user’s social circle. Furthermore, CovApp 2.0 can be used to identify patients who may be suitable for trials or special therapies, for example, with monoclonal antibodies. Monoclonal antibodies can improve survival rates in a subset of patients who are immunocompromised, but they must be administered very soon after the onset of symptoms in order to be effective.
Weekly updates
For CovApp to come to the right conclusions, the scientists had to build the requisite knowledge into the app. To do so, they developed a decision logic that enables them to concisely formulate rules and easily check their validity. “Thanks to this new method, we can make adjustments to the app very quickly,” explains Thieme. “We plan to release a CovApp update every week, so that it always reflects the current pandemic situation.”
“The various vaccines entering the market gave rise to new questions,” says Thieme, explaining the necessary update to the app. “We know that even vaccinated or recovered people can still get infected under certain circumstances – for example, if they are taking immunosuppressants or have not yet reached full immunity.” At present, the app can recognize a total of more than 20 different clinical scenarios and provide appropriate advice for action. It is important to emphasize that CovApp only gives recommendations; decisions regarding treatment are always made by doctors. CovApp was developed by a team of Charité physicians from the Institute of Hygiene and Environmental Medicine, the Institute of Tropical Medicine and International Health, and the Department of Infectious Diseases and Respiratory Medicine, as well as epidemiologists from the Robert Koch Institute. The goal was to create an app that could serve as a comprehensive guide through the pandemic.
Donating data for research
The app also offers a useful feature to promote further research into COVID-19, as anyone who answers the questionnaire can voluntarily donate their data for scientific purposes. “We want to be able to identify local coronavirus outbreaks via the spatio-temporal clustering of such things as symptoms or positive rapid tests,” Thieme reports. The physician also believes that early detection of a fourth wave may be possible if the app is once again well received and downloaded by enough users.
In 2020, several million Germans downloaded CovApp and filled out the questionnaire; an international version was also rolled out for the United States and Italy.
Link to the CovApp
The CovApp is also available as a WebApp at https://covapp.de or https://covapp.charite.de.