The director of the National Institute of Allergy and Infectious Diseases (NIAID) and President Joe Biden’s chief COVID adviser told MSNBC’s Andrea Mitchell that there is no “mathematical equation” to definitely say when we’ll be back to life as we knew it. “There are so many things in play that could influence and then it also depends on what you mean by ’normal,’” Fauci explained. “What does some form of normality mean?” If you’re talking about “getting back to a situation where you can have theaters that might be able to have below capacity, that restaurants, indoor dining can be happening, but with moderately diminished capacity,” Fauci said, “that’s going to be somewhere between the fall and the end of the year.” And for more on how you can dine safely now, check out Dr. Fauci Just Said This Is the Only Safe Way to Eat at a Restaurant. “If you say, ‘No, no, no, wait a minute. I really want to know when it’s going to get to as close to normal that you almost don’t know the difference between what it was before’ … that likely will be, as the president said, by the end of the year, by Christmas.” However, he warned Americans to be braced for the possibility that “maybe you’re going to still have to wear masks.“ae0fcc31ae342fd3a1346ebb1f342fcb “But … these are all estimates,” Fauci clarified. “And that’s the reason why when you ask people like myself and others, we say ’likely,’ because if it were a mathematical formula, I could give you a real number, but there are so many things that can happen.” And for more COVID news delivered right to your inbox, sign up for our daily newsletter. As Fauci insinuated, President Biden gave a similar timeline during a CNN town hall on Tuesday, Feb 16, setting Christmas as the administration’s goal for a possible return to normal life post-COVID. “As my mother would say, with the grace of God and the goodwill of the neighbors, that by next Christmas I think we’ll be in a very different circumstance, God willing, than we are today,” Biden said. “A year from now, I think that there’ll be significantly fewer people having to be socially distanced, having to wear a mask.” However, he also added: “I don’t want to overpromise anything here.” And for more on the latest mask guidance, check out This Is When You Shouldn’t Double Mask, CDC Says. But Fauci was open about the different factors that will weigh on the government’s decisions about when to reopen different parts of society and to end certain mandates. “So many things can happen to modify that [timeline],” he told Mitchell. “Namely the variants can come in and we may be able to see a situation, unfortunately, where you have an increase or a little blip, which would interfere with that timeline.” As of now, the Centers for Disease Control and Prevention (CDC) warns that the U.K. variant in particular is a threat. The new strain, which has since been proven to be more transmissible and deadlier, is poised to become the dominant form of COVID in the U.S. by March. Still, Fauci is optimistic. “I still hold that somewhere between the fall and the winter we’re going to wind up seeing [a return to normalcy],” he said. And for the latest on your COVID risk, check out If You Have This in Your Blood, You May Be Safe From Severe COVID.