중남미

In early 2020, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a public health emergency of international concern. A month later, this disease was declared a pandemic. Reference Jee1 Throughout the three years of the pandemic, new variants, lineages, and sublineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged, provoking several waves of infections around the world. 2,3 In November 2021, Omicron appeared in the world and has been the variant that has caused the most COVID-19 cases worldwide, partly because of all the highly contagious lineages and sublineages that have arisen from this.