COVID-19 pandemic: The World Health Organization identifies the SARS-CoV-2 Omicron variant.

The global COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an outbreak in Wuhan, China, in December 2019. It spread to other parts of Asia and then worldwide in early 2020. The World Health Organization (WHO) declared the outbreak a public…