If you're vaccinated, "we've done the right thing, and we will get through this," White House COVID coordinator Jeff Zients said.
"For the unvaccinated, you're looking at a winter of severe illness and death for yourselves, your families and the hospitals you may soon overwhelm."
In a briefing with reporters on Friday, Zients and the White House COVID-19 task force, which includes Centers for Disease Control and Prevention Director Rochelle Walensky and chief medical advisor Anthony Fauci, highlighted the importance of initial vaccines, which offer strong protection against severe illness, but strongly emphasized the need for fully vaccinated Americans to go out and get their booster shots, which offer the best protection against the new omicron variant.
"The optimum protection is fully vaccinated plus a boost," Fauci said.
"So the bottom line of what we've been telling you all along: It is critical to get vaccinated. If you are vaccinated, it is critical for optimal protection to get boosted," he said.
Asked if the task force is considering recommending people get boosters earlier than six months after their final shot, the current standard, Fauci said it's "on the table."
"You still get protection that's reasonably good against hospitalization [with two shots]. We want to make that better with the booster," he said.
"Whether or not we're going to change what the time interval between your last vaccination and your boost, we always have these on the table for discussion, but right now there has not been a decision on that," Fauci said.
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Only 30% of fully vaccinated Americans have been boosted so far, and about half of fully vaccinated seniors over the age of 65 have been boosted.
But Zients said those numbers are slightly higher among eligible Americans -- people who are six months past their final shot.
"The right way to think about the percent boosted is those eligible. And we've now boosted about 60 million Americans. That's about 40% of the eligible Americans. Importantly, of those over 65 we are now more than 60%. And that's important because they are the most vulnerable," Zients said.
Still, that means the percentage of boosted Americans with optimal protection against omicron is quite low, at about four in every 10 vaccinated people. And around 40% of the country still remains completely unvaccinated.
The warnings from the White House come in the lead up to Christmas and New Year's -- the first since vaccines became widespread in the US. The holiday season has coincided with the presence of omicron, the most transmissible variant to date.
Yet the holiday guidance from the White House COVID task force continues to be that Americans can and should gather, given the existence of vaccines -- a powerful mitigation tool against the virus.
But vaccines alone are not sufficient to ensure full protection, the CDC director warned, and Americans should return to the basics to steer clear of a holiday outbreak among family members.
That includes indoor masking in all public places, ruling out indoor dining or bars, social distancing, hand-washing and spending time in well-ventilated areas. But historically, the country has had a hard time sticking to these measures and is particularly fatigued two years in -- circumstances that do not bode well for avoiding a surge this holiday season.
"I think we're in a very different place this year than we were last year, and we really do want people to be able to gather and gather safely," Walensky said.
"We have the tools now to do it and what we're really saying is please rely on those tools. Get vaccinated. If you're eligible for a boost, get boosted. And importantly, a week before the holidays, indoor mask in these areas that have -- 90% of our counties have substantial or high transmission," Walensky said.
"Use the next week to make sure you're practicing those safe prevention mitigation strategies, so that when you come together for the holidays, that people have been not exposed to the virus because in fact they've been vaccinated, boosted and masked. And for that extra reassurance as we have more disease in this country right now, do a test and make sure that you're negative before you mix and gather in different households," she said.