graph showing how the perceived risk of getting or dying of covid has varied over time
Data as of mid-March 2020. Graphic by Sara Chodosh

This winter, a worrying trend emerged: although COVID-19 cases were at an all-time high, polling data indicated that many Americans were taking more risks and fewer precautions against the virus. Even as case counts rose, people seemed to care less.

The national third wave peaked at more than 300,000 cases in a single day on January 8. Yet data collected by researchers at the University of Southern California since the beginning of the pandemic shows that Americans’ perception of personal risk of contracting COVID-19 peaked in April of last year, quickly declined, and has steadily plateaued over the past 11 months.

Clearly, the amount of risk perceived by most Americans doesn’t correlate at all with fluctuations in case numbers. Personal risk perception was at its highest in April, during the smallest of the three waves so far. The percentage of Americans who reported self-quarantining peaked at 55 percent that month, just after the pandemic began, and the fraction who say they are self-quarantining and avoiding contact with others has dropped to the lowest level since last October, to just 13 percent. Cases are still high now, but a sizable portion of Americans have already begun looking forward to—and resuming—normal pre-COVID activity.

This relationship—or lack thereof—might seem perplexing. But the truth is, risk isn’t the only thing we consider when making choices in a pandemic. There are a multitude of factors that underlie how we perceive risk and then choose to act on those perceptions, many of which aren’t about hard data.

Wändi Bruine de Bruin, a professor of public policy, psychology, and behavioral science at USC and one of the researchers behind the USC survey, says that risk perception probably hit an all-time high in April of last year because we were sailing into uncharted waters.

“Perceived risk shot up in April when a lot of states were going into lockdown and hospitals were getting more full, and people were realizing, ‘oh, this is quite serious,’” Bruin explains. “Then over time, perceived risk has slowly gone down, I think partly because people are getting used to coronavirus being around and partly because people have observed that even though some people die from it, the majority does not.”

Even when cases began to climb over the summer and fall, perceived danger didn’t follow. That’s because we calculate risk with the input of two main factors: our own real-world experiences, and the information we receive from various sources.

We might consider ourselves at low risk if the people around us are not getting sick or dying from the coronavirus. On the other hand, if people with COVID are surrounding us, we will likely consider the level of risk to be a lot higher. That’s personal experience at play, says Bruine de Bruin.

With hard info, Bruine de Bruin says the way we apply information to our risk perception depends on how much we trust the people sharing it. If an expert says we should be worried about COVID-19 in our community, and we trust this expert, we are more inclined to perceive a high level of risk. If we don’t, our risk perception likely won’t change.

Our sense of threat is also shaped by where we get our information from and how much news we consume. If we are constantly bombarded by reports of high case counts and hospitalizations, we are more likely to perceive high risk than someone who avoids the news or consumes stories that downplays high case counts, for example.

Taken together, it is likely that American’s perceptions of risk are highly fragmented because our personal experiences and the information we’ve received over the past year have not converged on a common narrative.

The response to COVID-19 has varied from state to state, leading to vastly different experiences. Rampant misinformation, from former President Trump to social media and Fox News, has disrupted the exchange of accurate information between experts and the public. All of this has made it challenging for a shared understanding of risk perception—and the corresponding behavioral response—to emerge nationwide.

Ironically, it might actually be our capacity for cost-benefit analysis and adaptability—combined with the fatigue of a dragging pandemic—that’s led us to ease up on our most restrictive behaviors, even as case counts remain high.

Humans have a remarkable capacity for what researchers call cognitive control, explains David Badre, a neuroscientist at Brown University. That’s our ability to perform new tasks or behaviors quickly, without lots of training (or centuries of evolution).

[Related: How to distinguish COVID-19 symptoms from a cold]

Badre says it was this cognitive control which allowed us to implement new public health practices, like mask wearing and social distancing, and almost immediately. “The fact that we were able to do so in a matter of days or weeks at the outset of the pandemic is due to our unique capacity for cognitive control,” he explains.

Over time, however, changing conditions and shifting risk-reward tradeoffs may make it less advantageous for us to continue exerting mental effort to follow guidelines—basically, pandemic fatigue. “As time goes on, people become less and less adherent to pandemic mitigation behaviors like social distancing,” he says.

This fatigue actually stems from our cognitive control abilities. In weighing any decision or task, we compare the costs of carrying out an action with the benefits. “Cost-benefit tradeoff drives our motivation to engage in any task or behavior, including those related to COVID,” he says. “Many reasons, like the mental effort needed to constantly accommodate new rules or the opportunity costs, that might change this cost-benefit balance over time, resulting in a loss of motivation.”

Bruine de Bruin also notes that perceived benefit may be beginning to outweigh perceived risk as the pandemic drags on. “It feels like it’s becoming more and more difficult to stay at home, to have not seen your friends and family for so long,” she says. “It’s difficult to stay home that long and to miss out on new social interaction, and that’s especially difficult for younger people. People may be less willing to continue to engage in social distancing, because staying away is hard at this point.”

Even if personal risk perception is beginning to slip, all hope is not lost. While the USC survey only asks respondents about their perceived personal chances of contracting or dying from the coronavirus, Bruine de Bruin points out that it’s important to distinguish between personal risk and community risk. People do have the ability to keep our protective behaviors engaged in order to protect those we perceive as vulnerable, both in our inner circles and in our wider communities. Those who feel a low level of personal risk may still choose to be cautious out of concern for others.

“There might also be people with low risk perception who may wear masks and socially distance, if they’re concerned about others,” Bruine de Bruin says. “People don’t like having it on their conscience that they’ve spread it to others who might be vulnerable.”

With the possibility of vaccination on the horizon for most American adults, we are close to the final stretch of the pandemic. Even if we feel ready to throw caution to the wind for a night out with friends we haven’t seen in months, perhaps finding the motivation to protect our communities by protecting ourselves will allow us to cross the finish line strong.