Coronavirus Variant Emergence and Epidemiology

The epidemiology of SARS-CoV-2 is highly complex and dynamic as new scientific studies, and the evolution of the virus itself leads to more variants emerging over time. This chapter provides a distillation of the fundamentals of virology for the layperson to understand. First, we explain how a virus is biologically defined through terms such as lineages, variants, and strains. Understanding the mechanism of infectivity of SARS-CoV-2, and how it has evolved to become more dangerous over time, is explored in deeper detail as well. Furthermore, we discuss how viruses are generally named and how the current naming system for SARS-CoV-2 has been established. Lastly, we discussed variant classifications of variants of interest (VOI), variants of concern (VOC), variants being monitored (VBM), and variants of high consequence (VOHC) at the time of writing.