Omicron variant may have evolved in rats, one theory says

Mask mandates saved lives & prevented COVID-19 infections in Missouri’s biggest cities during the worst part of the delta variant wave, an analysis by the state Dept of Health & Senior Services shows.The analysis, conducted at the request of Gov. Parson’s office in early Nov, was never made public.

Covid-19 news: Omicron linked to sharp rise in cases in South Africa

Previous Covid Infection May Not Protect Against Omicron, Scientist Warns, As Data Suggests Variant Is Overtaking Delta In South Africa