The United States reached a grim new milestone last week: More than 900,000 people across the country have now died from Covid-19. The daily death toll is at its highest level in about a year, rising 39% over the last two weeks, according to data compiled by Johns Hopkins University.

So why does it seem like so many people are back to living like it's February 2020? Packed bars. Unmasked travelers in airports. Most recently, four states — Oregon, Delaware, New Jersey and Connecticut — announced that they would soon end school mask mandates.

Experts say there are plenty of reasons for the phenomenon, many of them psychological – ranging from pandemic fatigue to an assumption that the worst must already be over. And that's a problem: A false sense of security could make it easier for another virus surge to emerge in the coming months, prolonging the pandemic and leading to even more widespread disruptions of schools, businesses and health systems.

"In the United States, we've normalized a very high death toll," says Anne Sosin, a fellow at Dartmouth College's Nelson A. Rockefeller Center for public policy. "Ironically, it's prevented us from being able to return to any sort of 'normal.'"

Why pandemic fatigue exists: 'It's so overwhelming'

Unlike past waves, omicron's massive death toll seems to have barely made a ripple in people's consciousnesses. This is a mix of pandemic and compassion fatigue, says Marney White, a psychologist and epidemiologist at the Yale School of Public Health.

"Many people view the omicron variant as a low threat to them, either because they're already vaccinated, or they've already had the Covid-19 virus," White explains. "They've deemed their personal risk to be minimal, and feel that they've sacrificed enough."

Pleas to think of the elderly, or the immunocompromised, or those too young to get vaccinated, can often fall on deaf ears. So too can the argument that cutting off omicron's spread would help prevent the virus from mutating into an even more dangerous variant.

"We've stopped interpreting this as a collective battle that we all need to fight," White says.

That sheds light on why people seem to have "normalized" the death toll, says Gale Sinatra, a professor of psychology at the University of Southern California.

"Research shows that we have a human tendency to turn away from mass suffering, as a form of self-preservation," Sinatra says. "The fact that the United States now has over 900,000 deaths from Covid-19 seems almost impossible to wrap our heads around. Our brains resist processing that information because it's so overwhelming."

More recently, people might be expanding their pandemic risk tolerance because they've seen a recent nationwide decline in overall Covid cases: As of Feb. 2, cases were down 53.1% from their peak on Jan. 15, according to the CDC.

That makes it easy to assume the worst is already over, says Dr. John Swartzberg, an infectious disease specialist at the University of California, Berkeley.

"We know that hospitalizations and deaths counts tend to go down two to four weeks after cases," he explains.

Covid numbness is prolonging the pandemic

The truth is, experts say, we're not going back to "normal" any time soon: The Centers for Disease Control and Prevention currently projects as many as 60,000 new Covid deaths by the end of February.

But the perception that normal is just around the corner can be damaging, Swartzberg says.

"One of the biggest mistakes that we've done throughout this pandemic is relaxed restrictions such as masks and social distancing too soon after each surge," he says. "As a result, we end up with a new baseline of cases higher than from where we started in the previous surge."

The result, he stresses, is even more outbreaks and the inevitable flight cancellations, delivery delays and school closures.

"It's frustrating for Americans, but it's even more frustrating for us infectious disease experts, because we know that if we'd just waited a few more weeks, much of this could have been avoided," he says.

Even once the current wave subsides, our definition of "normal" may need to change, too: Living with Covid won't be as simple as pretending it doesn't exist anymore. Sinatra suggests, for example, that masks could be required on flights or in large venues during the fall and winter, going forward.

Those sorts of measures may be necessary to prevent future disruptions to businesses, schools, and other walks of life. "Wearing masks isn't what's sidelining workers from their jobs and taking kids out of schools — it's Covid," Sosin says. "If we don't control this virus, it will end up controlling us — permanently."

One way to help bury the current surge is to make sure you and your loved ones are vaccinated and boosted, if eligible. If you haven't gotten your booster dose, you're at increased risk of a breakthrough omicron infection, Swartzberg says – raising your chances of enabling the virus' continued spread, developing long Covid, being hospitalized or even dying.

As of Wednesday morning, less than 50% of Americans who are booster-eligible have gotten that shot, according to the CDC.

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