Vaccine makers are racing to update their COVID-19 shots against omicron even before it’s clear a change is needed, just in case.
Experts doubt today’s vaccines will become useless, and the first hints this week suggested boosters likely do offer some protection against the newest variant threat. But further tests are underway to tell if it’s enough, or if protection has dropped enough to warrant a recipe change. It’s not clear how big a drop would trigger such a drastic move.
Pfizer and Moderna have practiced tweaking their shots against earlier mutants so they’d know how but brewing new doses still would take months.