Funding for this research was provided by:
Bundesministerium für Gesundheit (ZMVI1-2516-AUK-701 / BMG: 321-4471-02/157)
China Scholarship Council
Deutscher Akademischer Austauschdienst
Received: 8 November 2018
Accepted: 22 February 2019
First Online: 4 March 2019
Ethics approval and consent to participate
: Not applicable. According to IfSG §13 (2017), the RKI is authorized to receive anonymous blood residuals from diagnostics laboratories for surveillance purposes. The KOKPIT study has been approved by the data protection officer of the RKI.
: Not applicable.
: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.