Just as friends and loved ones were gathering to celebrate Thanksgiving and kick off the holiday season, a very unwelcome visitor showed up on the scene: omicron, a new variant of the virus that causes COVID-19. Scientists in South Africa reported the coronavirus variant early last week, and the World Health Organization named it a “variant of concern” days later. Cases of the new lineage have now surfaced in more than a dozen other countries.

Though the public has grown accustomed to hearing about new coronavirus variants emerging from all corners of the world, omicron has researchers particularly on edge. Suresh V. Kuchipudi, a virologist and expert in emerging infectious diseases from Penn State, explains the biology behind the variant’s startling array of spike protein mutations and what that might mean for its ability to spread and dodge the vaccines based on that protein. Kuchipudi also writes about how the delta variant dominated the globe and what the research community has learned from its rapid circulation.

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Amanda Mascarelli

Senior Health and Medicine Editor

The omicron variant possesses numerous mutations in the spike protein, the knob-like protrusions (in red) that allow the virus to invade other cells. Juan Gaertner/Science Photo Library via Getty Images

Will omicron – the new coronavirus variant of concern – be more contagious than delta? A virus expert explains what researchers know and what they don’t

Suresh V. Kuchipudi, Penn State

It’s too early to say whether the newly identified omicron variant is going to overtake delta. But particular mutations in the new strain have researchers deeply concerned.

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