EXPLAINER: Boosters key to fight omicron, lot still to learn

By LAURAN NEERGAARD and CARLA K. JOHNSON
AP Medical Writers

The new omicron variant took only a few weeks to live up to dire predictions about how hugely contagious it is. But scientists don’t yet know if it causes more severe disease even as the world faces exploding cases just before Christmas. Vaccines in the U.S. and around the world do not offer as much protection against omicron as they have against previous versions of the coronavirus. However, vaccines still help _ a lot. Lab tests show while two doses may not be strong enough to prevent infection, a booster shot of either the Pfizer or Moderna vaccine produces virus-fighting antibodies capable of tackling omicron.