As the number of coronavirus cases tops 100,000, more and more people are panic-buying items like hand sanitizer, toilet paper, and face masks.

Kelly Goldsmith, a former Survivor contestant turned academic expert on scarcity, tells Business Insider this hoarding is the result of fears over health, economic stability, and a desire to protect one's self.

But given we live in a shared society, just protecting yourself isn't enough to save you from the possibility of getting a communicable disease.

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To her students at Vanderbilt University, Kelly Goldsmith is an expert on consumer behavior in the face of scarcity. To Survivor fans, she's a trooper who lasted 24 days in the searing Kenyan heat on the third season of the reality TV show.

But to people anxious about the new coronavirus, she's one of a few people in the world that understand exactly what is motivating the Purell-hoarding and panic-buying that's going on in countries around the world.

Goldsmith was a behavioral research analyst before she became the youngest contestant on her season of Survivor. "The show was like a crash course in bizarre human behavior," she said. "Essentially, it's like an experiment about safety and deprivation that unfolds on national television in front of millions of viewers."

After the show, she headed to Yale to get a PhD in digital marketing, examining what drives the decisions people make. After graduating in 2008, during the economic recession, Goldsmith examined scarcity and uncertainty in a different environment, worrying about her hireability in a time when 2.6 million people were unemployed.

Now an associate professor at Vanderbilt, Goldsmith is an expert on how consumers respond to uncertainty, which the coronavirus has stoked globally.

We live in a society where we have no motivation to take care of one another

In Goldsmith's time on Survivor she found that, contrary to all the existing research on scarcity, the 15 other castaways she competed with weren't hostile or aggressive when trapped in an environment of scarcity. They all banded together to cope with the dangerous wildlife and sweltering weather, showing each other empathy.

But unlike Survivor, many people are responding to the global coronavirus outbreak by hoarding toilet paper and Purell, and fighting in chain stores for the last face mask.

"One thing that distinguishes my experience on Survivor from what's happening in Walgreens or CVS right now is that on Survivor, you succeeded by having people like you and by building positive social relationships," said Goldsmith. "So our scarcity made us strategic. As a part of that strategy, we were kind."

But in the real world, "we are not in a context where we see ourselves as benefiting by helping others," said Goldsmith. "If I buy six containers of Purell, and hand them to my neighbors, it doesn't necessarily benefit me in terms of my likelihood of withstanding the coronavirus."

Shelves that held hand sanitizer and hand soap are mostly empty at a Target in Jersey City, N.J. AP Photo/Seth Wenig

Goldsmith's research showed her that, when people are experiencing personal scarcity, they want to protect themselves first. "They don't want to hurt others, but they want to preserve their own security, health, and safety," she said. "The problem is, we've set up a situation where there's no benefit being portrayed to consumers associated with helping others, other than just being a good person."

In times of plenty, individuals value altruistic behavior because it makes them feel moral and helpful. "That desire for that warm glow drives a lot of consumer behaviors that can't be explained by anything else," said Goldsmith. But research shows being a good person tends to take a backseat when you're experiencing a personal threat.

"This coronavirus is very much a threat towards our economic stability and our health," said Goldsmith, "and when we go into that self protective mode, we're going to be grabbing all the Purell, we're going to be pushing people out of the way to the toilet paper, not out of malicious intent, but out of the desire to protect ourselves."

This disease will not affect everyone the same way

"We can't pretend that this disease is indiscriminate," said Goldsmith. "Those who have less are more exposed and vulnerable and and with the product hoarding we've seen, it does create a situation where the poor get sick and the rich get well."

The US is characterized as a society that prides itself on its independence, compared to other societies in the world, like China, Pakistan, and Greece, that value interdependence — i.e.: the extent to which they rely on others.

"You can imagine, if we were a more interdependent society, you might not see as much of this self-serving behavior," said Goldsmith, "because a threat like coronavirus might be interpreted more as a threat to the broader social collective we want to maintain and preserve."

But in the US, Goldsmith says, the virus is being interpreted as an individual threat, so people are responding by protecting themselves.

"That enables some people who can to pay $80 for Purell on Amazon to feel safe and secure, where people who don't have the financial resources are left out in the cold," she said. "In a time of uncertainty, money can buy you stability, and those who have more money can buy more stability."

A man exits a supermarket outside the small Italian town of Casalpusterlengo. Guglielmo Mangiapane/Reuters

Product-hoarding will not protect you from the coronavirus

If one person goes to the store and buys up all the hand sanitizer, they aren't protecting themselves as much as they think they are.

"Even if you have all the Purell in the world, other people have dirty hands and we're all using the same door handles," said Goldsmith, pointing out that she thinks New York State is doing a good job in making hand sanitizer available to the public. Everyone lives in a shared society, and just taking care of oneself, by panic-buying all the hand sanitizer, isn't enough to protect against a communicable disease.

"The language around the virus has been about social isolation, social distancing, telling people as a consumer they're in this alone fighting for themselves," Goldsmith said. "It's possible if we had more of an interdependent mindset, we might be able to help ourselves more."

Goldsmith says the times we live in definitely feel like a reality show. Maybe an early episode of Survivor, or maybe a dark, gritty sci-fi movie. In early March, half of Goldsmith's Nashville, Tennessee town was decimated by a tornado. This week, her classes are cancelled because of coronavirus.

"You layer on top of political divisiveness and economic instability and it really feels like we don't know what's going to happen," she said. "But I always like to believe there's promise in uncertainty. There's room for potential."

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