Jan 7: The more infectious Omicron variant of COVID-19 appears to produce less severe disease than the globally dominant Delta strain, but should not be categorised as "mild", World Health Organization (WHO) officials said on Thursday.

ATLANTA, Dec 9: More than 40 people in the U.S. have been found to be infected with the omicron variant so far, and more than three-quarters of them had been vaccinated, the chief of the CDC said Wednesday. But she said nearly all of them were only mildly ill.