Evolution of vaccines against COVID-19: From the initial strain to the Omicron variant.

Abstract

Vaccines represent one of the most impactful public health advances in human history, playing a fundamental role in reducing the transmission and, in some cases, eliminating infectious diseases. Since the sudden appearance of the SARS-CoV-2 virus and the onset of the global health emergency, several vaccines have been designed and licensed to address the COVID-19 pandemic in 185 countries around the world. It is therefore important to be aware of the different types of vaccines available and the facts regarding their efficacy and safety. The World Health Organization (WHO) reported as of November 8, 2022, 12,885,748,541 doses of COVID-19 vaccines administered worldwide, while, in Mexico, the secretary of health reported as of December 23, 2022, 227,341,091 doses of COVID-19 vaccines. As more vaccines are approved, it is important to track data on vaccination efforts in Mexico and discuss the need to incorporate effective preparedness and response mechanisms that include innovative vaccine production platforms in our country. The objective of this manuscript is to present to the reader the current vaccines approved against COVID-19, the variants of interest and concern identified by WHO, and to discuss the implications regarding the emergence of the new variants on the efficacy and safety of licensed vaccines.