Received: 31 March 2020
Accepted: 15 September 2020
First Online: 6 October 2020
Ethics approval and consent to participate
: Some human sera were obtained as part of the German health interview and examination survey of adults (DEGS1). DEGS1 was approved by the ethical review board of the Charité Medical School, Berlin, Germany (No. EA2/047/08).
: Not applicable.
: The authors declare that they have no competing interests.