The clinical course and outcome of COVID-19 are highly variable, ranging from
asymptomatic infections to severe disease and death. Understanding the risk factors of …

Objectives To compare severity and clinical outcomes from Omicron as compared with the
Delta variant and to compare outcomes between Omicron sublineages. Methods We …

After the global spread of the SARS-CoV-2 Omicron BA. 2, some BA. 2 subvariants,
including BA. 2.9. 1, BA. 2.11, BA. 2.12. 1, BA. 4, and BA. 5, emerged in multiple countries …

The BA. 2 sublineage of the SARS-CoV-2 Omicron variant has become dominant in most
countries around the world; however, the prevalence of BA. 4 and BA. 5 is increasing rapidly …

Summary Background Among the Omicron sublineages that have emerged, BA. 1, BA. 2,
BA. 5, and their related sublineages have resulted in the largest number of infections. While …

Abstract Background Although the SARS-CoV-2 Omicron variant is considered to induce
less severe disease, there have been no consistent results on the extent of the decrease in …

The COVID-19 pandemic has been met with an unprecedented response from the scientific
community, leading to the development, investigation, and authorization of vaccines and …

Abstract The SARS-CoV-2 Omicron subvariants BA. 1 and BA. 2 exhibit reduced lung cell
infection relative to previously circulating SARS-CoV-2 variants, which may account for their …

Expansion of the SARS-CoV-2 BA. 4 and BA. 5 Omicron subvariants in populations with
prevalent immunity from prior infection and vaccination, and associated burden of severe …

Background In this study, we compared admission incidence risk and the risk of mortality in
the Omicron BA. 4/BA. 5 wave to previous waves. Methods Data from South Africa's SARS …