. 2021 Mar 13;10(3):336. doi: 10.3390/pathogens10030336
© 2021 by the authors.
Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Figure 1.
Geographical origin of the study participants.