All coverage
WHO labels new Covid strain, named omicron, a 'variant of concern,' citing possible increased reinfection risk
By Robert Towey & Sam Meredith
U.S. President Biden calls for intellectual property protection waivers after Omicron discovery
By Nandita Bose, Heather Timmons & Lucia Mutikani
What to know about the omicron variant and subvariant BA.2
By Lindsey Bever, Joel Achenbach & Meryl Kornfield
What's known and unknown about Omicron, the coronavirus variant identified in South Africa
By Andrew Joseph
What to know about omicron, the new COVID variant
By Michaeleen Doucleff
Omicron: What we know about Covid strain prompting fresh global restrictions
By Clive Cookson & Oliver Barnes
U.S. imposes travel ban from eight African countries over Omicron variant
By Nandita Bose & David Shepardson
U.S. to restrict travel from South Africa, 7 other countries as new Covid variant emerges
By Leslie Josephs & Christina Wilkie