Clinical factors associated with viral shedding time of SARS-CoV-2 Omicron variant in Japan.

The Omicron variant of severe acute respiratory syndrome coronavirus 2 exhibits increased infectivity compared with all prior variants, and the timing of quarantine release should be carefully considered. However, to date, only two Chinese studies have analyzed the association between the viral shedding time (VST) and risk factors among patients infected with the Omicron variant. These studies included only limited numbers of severe cases and no analysis of underlying diseases and immunosuppressive drug use.