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Moderna chief predicts existing vaccines will struggle with Omicron
By Jamie Smyth
Who's in? Who's out? The ethics of COVID-19 travel rules
By Nancy S. Jecker & Caesar A. Atuire
Existing vaccines might not be as effective against omicron variant, Moderna CEO says
By Timothy Bella & Adela Suliman
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Mask mandates to tackle Omicron come into force in England
By Alistair Smout & Paul Sandle
African leaders condemn travel bans from rich nations to stem omicron variant : Goats and Soda
By Joe Hernandez
Wealthy nations starved the developing world of vaccines. Omicron shows the cost of this greed
By Deborah Gleeson
COVID-19: How the spread of Omicron went from patient zero to all around the globe
By Philip Whiteside
COVID: First signs that vaccines protect against Omicron
By Maayan Jaffe & Rossella Tercatin
What We Know About Omicron, BA.4 and BA.5
By Andrew Jacobs, Carl Zimmer & Emily Anthes
'The world is watching South Africa': health experts sift Omicron clues
By Joseph Cotterill, John Burn-Murdoch & Oliver Barnes
Markets fall on Omicron fears as officials offer vaccine reassurance
By Ludwig Burger & Emma Thomasson
Omicron variant was detected in the Netherlands before S. Africa flights
By Bart H Meijer, Louise Heavens & Anthony Deutsch