Omicron vs Covid-19 vaccines: What more do we need to know?

Data is still needed on how protective Covid-19 vaccines remain in real-world use against the highly mutated Omicron variant.

Laboratory studies released this week suggest that the Omicron variant of the coronavirus will blunt the power of Pfizer and BioNTech's vaccine to prevent Covid-19 infection after two doses, although a third dose may restore that protection.