The CDC is now calling for everyone age 18 and up to get a booster shot, while potentially expanding eligibility to 16 and 17-year-olds.
But some say its success is questionable after Moderna's CEO, Stephane Bancel announced vaccines might not offer as much protection against the new Omicron variant from South Africa.
All three vaccine makers are now prepared to update their vaccine contingency plans if necessary, although that could take months.
The reports of a highly contagious new variant sent shockwaves through financial markets Tuesday, leading to another big market selloff after Friday's major plunge. With Omicron already spreading across continents, concerns are growing about more potential lockdowns. There are more than 200 confirmed cases of this version of COVID-19 in at least 20 countries.
Washington's COVID-19 Task Force said it would take about two weeks of studying Omicron's mutations to better understand the transmissibility and severity of the variant. Some scientists in South Africa have said Omicron is more contagious but its symptom may be less severe. It's too soon to know for sure.
News of Omicron overshadowed a federal judge's temporary injunction Monday on the Biden administration's vaccine mandate for health care workers across 10 states.
The future remains uncertain and Biden signaled that lockdowns were off the table, but only if Americans follow his rules. "If people are vaccinated and wear their mask, there's no need for lockdown," President Biden said.
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