omicron variant

Moderna said its current FDA-authorized 50-microgram booster shot increased antibody levels against omicron 37-fold compared to pre-booster levels.

Sporting events and live theater announced cancellations amid major increases in new coronavirus cases, in large part because of the omicron variant.

Collins is retiring after 12 years of leading the federal health agency. He parts with a warning about the dangers of yielding to pandemic fatigue. "The virus is not tired of us," he says.

Dr. Raul Pino, medical director of the county's Department of Health, says the majority of COVID cases, hospitalizations and deaths in the region continue to be from the delta variant.

Nine states have active mask mandates, even as the new variant is quickly moving in on the U.S. Despite their political unpopularity, research shows masks still work and could save lives.

A new study from the University of Hong Kong offers preliminary information that could explain why this new coronavirus variant may be more transmissible.

The Moderna vaccine's ability to shield against infection drops sharply when tested on the omicron variant. But getting a booster pumps the protection back up again, new research suggests.

The test that found the omicron variant in Orange County sewage is considered preliminary. The city of Altamonte Springs also found the highly contagious strain in its sewage.

The U.S. also surpassed 50 million COVID-19 cases, the most in the world. Two experts who raised early warnings discuss how the losses continue to deepen, despite the arrival of vaccines a year ago.

The percentage of people saying they are highly worried is slightly lower than it was in August as the delta variant was taking hold, and still below the level of concern expressed through much of 2020.