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Omicron: What can we learn from South Africa's experience so far?
By Rachel Schraer & Peter Mwai
COVID-19 vaccines may be less effective against Omicron - WHO
By Hugh Lawson, Josephine Mason & Michael Shields
Lung tissue study sheds light on fast Omicron spread
By Lisa Schnirring
Omicron variant: What we know — and don't know
By Denise Chow
'No evidence' Omicron less severe than Delta, say UK researchers
By John Burn-Murdoch, Sebastian Payne & Oliver Barnes
What makes omicron spread so quickly? A new study offers a tantalizing clue : Goats and Soda
By Michaeleen Doucleff
Omicron and Its Symptoms: What to Know as Americans Are Catching the New Variant
By Denise Roland, Joanna Sugden & Daniela Hernandez
S.Africa reports record daily COVID-19 cases as Omicron spreads
By Alexander Winning & Mark Heinrich
Omicron more likely to reinfect than Delta, no milder -study
By Clara-Læïla Laudette