  With the Corona Virus Disease 2019 (COVID-19) pandemic spreading across the
world, protective measures for containing the virus are essential, especially
as long as no vaccine or effective treatment is available. One important
measure is the so-called physical distancing or social distancing. In this
paper, we propose an agent-based numerical simulation of pedestrian dynamics in
order to assess behaviour of pedestrians in public places in the context of
contact-transmission of infectious diseases like COVID-19, and to gather
insights about exposure times and the overall effectiveness of distancing
measures. To abide the minimum distance of $1.5m$ stipulated by the German
government at an infection rate of 2%, our simulation results suggest that a
density of one person per $16m^2$ or below is sufficient. The results of this
study give insight about how physical distancing as a protective measure can be
carried out more efficiently to help reduce the spread of COVID-19.
