OAKLAND (AP) — Public health officials say at least five people in Northern California have contracted the omicron variant of COVID-19, and the outbreak is linked to a wedding in Wisconsin last month.

The outbreak was announced Friday — just two days after the first U.S. case of the omicron variant was identified in California.

READ MORE: 'You Take Your Chances': Several Cars Stripped Of Catalytic Converters At Sacramento Airport Economy Lot

Much remains unknown about the new variant, including whether it is more contagious than previous strains, whether it makes people more seriously ill, and whether it can thwart the vaccine.

READ MORE: New Bill Allows For Hunting Of Destructive Wild Pigs In California Without A Permit

The five people are among a group of 12 who have tested positive for COVID-19 and are linked to a Nov. 27 wedding in Wisconsin.

MORE NEWS: 'Just Seeing Those Pictures Hurt': Sacramento Family Hasn't Heard From Tongan Relatives Since Eruption

(© Copyright 2021 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)