Evaluation of a SARS-CoV-2 test strategy in a southwestern university hospital at the beginning of the COVID-19 pandemic

Background At the beginning of the COVID-19 pandemic, the German Robert Koch Institute (RKI) published several guidelines addressing the medical health services helping to detect SARS CoV-2. Needing an available and specific test strategy regarding SARS-CoV-2, our own test strategy strictly followed these testing criteria. Materials and methods Using a retrospective analysis, we verified if such a test strategy was an effective tool in the context of infection prevention control and as reliable SARS-CoV-2 detection. Therefore, we analysed our own test results of suspected SARS-CoV-2 cases between 26 February and 6 April 2020. Additionally, we used a geovisualisation tool to visualise test frequencies and positive test results within different districts of Mannheim based on people's addresses. Results There were on average 7% positive test results of SARS-CoV-2 within a population with typical symptoms of COVID-19 (n = 2808). There was no positive test result within an asymptomatic population (n = 448). However, one positive test result turned out to be a nosocomial infection. Finally, geovisualisation highlighted a shift of test frequencies and local positive rates for SARS-CoV-2 from one district of Mannheim to another. Discussion In conclusion, our test strategy strictly based on testing criteria suggested by the Robert Koch Institute resulted in a steady rate of positive tests and allowed us to increase test capacity without causing numbers of nosocomial infections of COVID-19. Geovisualisation tools can offer support in analysing an ongoing spread of transmissible diseases. In the future, they could be used as helpful tools for infection prevention control, for example in the context of vaccination programs.