MORAGA, Calif. (KGO) -- By now, you've likely seen one of the most visible reaction to the coronavirus -- empty shelves at the grocery store.
There's no denying this is happening. What's a bit more puzzling is why this is happening.
Michal Strahilevitz admits she doesn't visit the grocery store much. But this online shopper and marketing professor from St. Mary's College went to Safeway to see the empty shelves for herself.
"This idea we're going to be in a situation where there's no food, and we have to have a year's supply of food and a year's supply of toilet paper. It's a bit surprising," said Strahilevitz.
Long lines only add to the anxiety of shoppers.
So does seeing the number of people testing positive for COVID-19 grow daily.
"I can't control how quickly it spread," Strahilevitz said. "What can I control? If I have enough toilet paper. If I have enough rice. And there's a comfort. To some extent that's what's causing the hoarding."
Glenn Friedman of Orinda had hoped to buy paper towels and toiletries, but left with none of those things.
He described shopping as crazed, yet calm.
"There's a lot more people getting along," he said. "You didn't see any of the type of atmosphere of people at each other's throats to be grabbing for things."
A study by the research firm Nielsen drew parallels between major news stories and a spike in buying of certain products.
The sale of medical supplies and rubbing alcohol surged nearly 20 percent after the first reported case of the virus in the United States on January 30.
Sales jumped 65 to 85 percent after the first reported person to person transmission of the disease on February 29.
Powdered milk sales also jumped 85 percent and rice and bean sales increased 25 to 37 percent.
"So I think when something becomes scarce, everybody wants more of it because they're afraid next time. There won't be any toilet paper at all," Strahilevitz said.
Major grocery stores have assured the White House that there's enough for everyone and are urging consumers not to hoard anything at this time.
Take a look at more stories and videos by Michael Finney and 7 On Your Side.