Acknowledgement
We thank Sven Schröder for technical support.
Funding: The work of Kristin Tolksdorf was funded as a research project by the German Ministry of Health.

Editorial note
This article was published as an e-Alert on 16 March 2020.

Conflict of interest: None declared.
Authors’ contributions: KT, SB, WH and ES established the hospital sentinel system. ES, KT and SB participated in the collection of the data, KT analysed the data. KT, SB, WH, ES and LHW were in involved in data interpretation. KT drafted the manuscript. All authors have contributed to the manuscript and approved the final manuscript.