How fast does it spread?: Scientists ask whether Omicron can outrun Delta

Several disease experts said there are strong grounds already for believing that Omicron will render vaccines less effective

As scientists race to understand the consequences of the Omicron COVID-19 variant, one of the most important questions is whether this new version of the coronavirus can outrun the globally dominant Delta variant.

The World Health Organization on Friday designated Omicron a "variant of concern" just days after the variant was first reported in southern Africa. The WHO said it is coordinating with many researchers worldwide to better understand how the variant will impact the COVID-19 pandemic, with new findings expected within "days and weeks."

Many questions remain, including whether Omicron will evade vaccine protection and whether it will cause more serious