(CNN) The US shouldn't ease restrictions in place to prevent Covid-19 before the number of new coronavirus cases falls below 10,000 daily, "and maybe even considerably less than that," Dr. Anthony Fauci said Thursday.
The US should pull restrictions gradually, after a substantial portion of Americans are vaccinated, Fauci told CNN's Jake Tapper.
The last time the US saw fewer than 10,000 new daily cases was almost a year ago, on March 22, 2020. The number hasn't fallen below 50,000 daily cases since mid-October, and the seven-day average on Wednesday was more than 64,000.
"We will be pulling back," said Fauci, President Joe Biden's chief medical adviser. "We're now up to about 2 million vaccinations per day. That means every day that goes by, every week that goes by, you have more and more people protected."
Fauci's comments come as some states begin to pull back restrictions, including doing away with mask mandates, allowing businesses to fully open and increasing the number of people allowed at mass gatherings.
That is "inexplicable," Fauci said earlier.
Not only are tens of thousands of Americans infected each day, but research suggests variants threaten another surge.
"I understand the need to want to get back to normality, but you're only going to set yourself back if you just completely push aside the public health guidelines -- particularly when we're dealing with anywhere from 55 (thousand) to 70,000 infections per day in the United States," Fauci told CNN's Erin Burnett on Wednesday.
Alabama on Thursday became the latest state to make a major announcement about masks. The state will allow its face-covering mandate to expire on the evening of April 9, Gov. Kay Ivey said.
Earlier this week, the governors of Texas and Mississippi said they were lifting mask mandates and allowing businesses to operate at full capacity immediately or within days, announcements that came as health experts warn that the spread of more-transmissible coronavirus variants risks sending infection rates soaring once again.
Of particular concern to health experts is the B.1.1.7 variant which was first identified in the United Kingdom and has now been found in 46 US states, as well as in Puerto Rico and Washington, DC.
A person with that variant can infect 43% to 90% more people than the older versions of the virus, according to evidence published Wednesday by researchers the Centre for Mathematical Modelling of Infectious Diseases at the London School of Hygiene and Tropical Medicine.
In a statement, the Infectious Diseases Society of America said the US must continue to use masks, social distance, wash hands and avoid large gatherings.
"We can't forget the lessons this pandemic has taught us or its terrible toll, and we must not relinquish the ground we've gained," said Dr. Barbara Alexander, the president of ISDA.
Dr. Rochelle Walensky, the director of the US Centers for Disease Control and Prevention, said Thursday state officials must continue to emphasize the importance of wearing masks for the foreseeable future, and "encourage everyone to roll up their sleeve for the vaccine when it's available to them."
California Gov. Gavin Newsom went a step further, urging people in his state to "consider using an additional mask and double masking" while in public.
Even in states where leaders are no longer requiring those measures, individuals can decide to "do the right thing" regarding distancing and masks, Walensky has said.
At least 16 states are now without statewide mask mandates.
With less than 7% of residents in his state fully vaccinated, Texas Gov. Greg Abbott issued an executive order Tuesday lifting a statewide mask mandate and allowing businesses to operate at 100% capacity, effective March 10.
"It is clear from the recoveries, the vaccinations, the reduced hospitalizations and the safe practices that Texans are using, that state mandates are no longer needed. We must now do more to restore livelihoods and normalcy for Texans," Abbott representative Renae Eze told CNN.
The governor said county leaders may opt to use mitigation strategies if regional Covid-19 hospitalizations rise above 15% of bed capacity for seven days straight. But they cannot impose jail time for people who don't follow Covid-19 orders, nor can residents be penalized for not wearing masks, he said.
In Mississippi, Gov. Tate Reeves said starting Wednesday the state would lift its county mask mandates and allow businesses to operate at full capacity, citing lower hospitalization and case counts. Mayors of cities including Jackson and Greenville said they will keep enforcing citywide mask mandates.
Some public health experts have urged states to wait, at least for far more vaccinations and lower cases levels, before easing safety measures like mask mandates.
Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, said Thursday that the more-transmissible B.1.1.7 variant was showing up in between 20% and 30% of the viruses obtained in surveillance checks in states including Florida, California and Georgia. Those figures -- just 1%-2% four weeks ago -- likely will double within 10 days, he said.
When that variant turned up in 50% in surveillance checks in parts of Europe and the Middle East, "we (saw) a major surge in (overall) cases" -- and the same could happen in the US, he said.
"Everything that the governors are doing right now to relax all the public health recommendations that we've made are only going to be a major invitation of this virus to spread faster and farther," Osterholm told CNN's "New Day."
Ohio Gov. Mike DeWine also announced revisions to public health orders Tuesday, including dropping a 300-person limit for events at banquet centers. Michigan Gov. Gretchen Whitmer unveiled a series of eased restrictions taking effect Friday, including expanded capacity for restaurants, retail, gyms, stadiums and other facilities.
And in Louisiana, the majority of businesses -- including restaurants and salons -- will be allowed to operate at 75% capacity starting Wednesday, while religious services will no longer have capacity limits, the governor said.
A third vaccine entered the US market this week after the US Food and Drug Administration gave emergency use authorization to Johnson & Johnson's one-dose product. Before this week, the only Covid-19 vaccines authorized in the US -- from Pfizer/BioNTech and Moderna -- were two-dose vaccines.
Health experts are excited about the new option, which they say is easily distributed due to its single-dose model and ability to be stored at normal refrigeration temperatures.
But some with the option to receive it have expressed hesitancy.
Because the public has heard that the shot is only 72% protective in the US, and the Pfizer and Moderna Covid-19 vaccines are about 95% protective, some will think this is a "second class" vaccine, experts have said. Experts say those numbers are highly misleading -- and are urging people to take whatever shot is first available to them.
"My big concern here is that the Johnson & Johnson is being labeled as the inferior vaccine," said Dr. Leana Wen, a CNN medical analyst and former Baltimore public health commissioner, "when that's not a fair assessment to make."
With limitations on distribution and the race to vaccinate Americans before another surge, some people may get to choose their vaccine, while others may not, officials have said.
That is the right choice for the current emergency, a team of bioethicists wrote in a commentary in the New England Journal of Medicine.
"In most aspects of US health care, patient preferences are paramount, and currently Americans remain free to decline vaccination against SARS-CoV-2. But among the willing, a policy limiting choice among vaccines will bring efficiencies to the fair distribution of a critically scarce resource," they concluded.
As of Thursday morning, 16.3% of the US population has had at least one shot of a Covid-19 vaccine, and 8.4% have had two.
Johnson & Johnson has set its sights on exceeding its target of 100 million doses by the end of June, CEO Alex Gorsky said.
And experts have estimated that vaccines will be available to all US adults by May, but the question of when children can be vaccinated isn't clear.
"Right now, we project that the clinical trials will give us information that by the time we get to the fall, high school students will be able to be vaccinated," Fauci said Wednesday. "I'm not sure if it's going to be by the first day of school, but sometime in the fall."
Their younger siblings will have to hold out a little bit longer, he explained, during a livestreamed town hall event with members of the United Food and Commercial Workers International Union.
"The way the program is now scheduled, children who are elementary school, 6 to 12, that group of individuals...those individuals will not be able to be vaccinated until their trials are finished, which will likely be at the earliest, the end of this year," Fauci said. "More likely the first quarter of 2022."