. 2022 Nov 23;10(4):112. doi: 10.3390/diseases10040112
© 2022 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 (https://creativecommons.org/licenses/by/4.0/).
Figure 1.
A timeline of the major COVID vaccines [25].