SARS-CoV-2 Omicron variant - Wikipedia
https://en.wikipedia.org/wiki/SARS-CoV-2_Omicron_variantThe omicron subvariant dominating U.S. COVID-19 cases is more vaccine-resistant : NPR
https://www.npr.org/2022/07/15/1111648759/covid-19-coronavirus-omicron-variant-ba5-cdc-vaccines-masks-mayo-clinic