The Covid‐19 world—Are we there yet?

Hamamoto, Yoshiyuki

The emergence of variants of respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and their rapid spread over the world casts a shadow over the potential victory for this human tragedy enabled by the novel and highly effective vaccines. Coronavirus disease 2019 (COVID‐19) cases surpassed 100 million on January 27, 2021 according to the Center for Systems Science and Engineering at Johns Hopkins University, which indicates that more than one of 80 humans on earth has already been infected. Some of the variants, especially the U.K. coronavirus variant (B.1.1.7), the South Africa variant (B.1.351), and the recently identified India variant (B.1.617) are more infectious and deadlier compared to SARS‐CoV‐2 before their appearance. The currently known major variants are characterized by mutations in the receptor‐binding domain of their spike‐protein (e.g., N501Y, E484K, and K417T/N); the India variant has two characteristic mutations of E484Q and L452R that may impact vaccine efficacy. COVID‐19 is distinguished from other infectious diseases by its two‐faced clinical presentation: it is sometimes almost asymptomatic despite its transmission potential or it may present with pneumonia that can lead to rapid disease progression and fatal outcome.