Estimation and Interactive Visualization of the Time-Varying Reproduction Number R _t and the Time-Delay from Infection to Estimation

R _t plays a key role in the development of the COVID-19 pandemic. The methods used for building an interactive website for the visualization of the time-varying reproduction number R _t and a novel way to visualize the time delay from infection to estimation overlayed with the R _t estimate are described and analyzed with regards to the influence of parameters chosen and compared to published estimates for Austria. Visualizing the time delays enables the interactive exploration of suspected changes in transmission and their effect on the R _t estimate.