Received: 28 November 2020
Accepted: 22 April 2021
First Online: 11 May 2021
: The study protocol was approved by the Ethics Committee of the National Medical Research Centre for Therapy and Prevention of the Ministry of health of Russian Federation (approval N 03–04/20, 24 April 2020).Written informed consent was obtained from participants via their online participation.All methods were carried out in accordance with relevant guidelines and regulations.
: Not applicable: this manuscript does not contain any personal data from participants.
: The authors declare that they have no competing interests.