Fears about a worsening coronavirus outbreak have led shoppers in the U.S. and other hard-hit countries to begin stocking up on supplies to fill "pandemic pantries," a new report from Nielsen suggests.

Among food goods with skyrocketing sales: oat milk. Sales of the product rose 305% in the week ending Feb. 22.

"Consumers around the world are actively stockpiling emergency supplies as concerns grow that the Novel Coronavirus (COVID-19) could become a worldwide pandemic," reads the report titled, "Nielsen Investigation: 'Pandemic Pantries' Pressure Supply Chain Amid COVID-19 Fears."

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Nielsen, which tracks more than 900,000 stores in 100 countries, found "significant spikes in the hoarding of emergency supplies" in the U.S., China and Italy.

The repercussions could be severe. The World Health Organization said Wednesday that panic buying and hoarding have contributed to a global shortage of face masks, which puts health care workers at risk.

Store shelves in Taiwan, China and Japan have been emptied of hand sanitizer, toilet paper, bleach and cleaning pads, and the U.S. is seeing similar patterns. At the same time, some sellers have begun to hike prices of desired products to gouge buyers. Amazon, eBay and Walmart have all said they are taking action to stop price gouging.

The demand is out there. Nielsen's report found sales of medical face masks in San Francisco drugstores are up 541% over a year ago and that sales so far this year have already surpassed those for all of 2019. Sales of medical face masks in Los Angeles drugstores rose 340%, Nielsen says.

Sales of household maintenance masks are skyrocketing nationwide, too, up 262% over the previous month.

"Stocks of hand sanitizers and medical face masks have already dried up in some markets, with no clear indication of when supplies will be replenished," Nielsen said.

The panic buying "ripple effect" is going beyond emergency items such as canned goods, flour, sugar and bottled water, to other non-food essentials such as vitamins, fruit snacks and first aid kits, says the report from Nielsen's consumer goods and retail research division.

Sales of dried beans rose 10.1%, while frozen fruit sales were up 7% in the week ending Feb. 22, the report says.

"Fresh food items are expected to face challenges as shoppers steer away from anything that may have travelled long distances, such as fruit and vegetables, or may have been exposed to the airborne virus," said Scott McKenzie, global intelligence leader at Nielsen.

Current shopping and stockpiling behavior is similar to that seen before snowstorms, he says. "That said, beyond the traditional focus on milk, bread and eggs, consumers now are even more focused on packaged products without extensive, direct contact, that perhaps were packaged during less severe stages of the outbreak," McKenzie said.

Nielsen research found that in Vietnam, 45% of consumers surveyed say they have increased what they’re stocking at home and 25% are buying more online.

"Beyond health preparedness, U.S. consumers aren’t waiting until it’s too late to stock up on shelf-stable essentials, which parallels what we’ve seen in other regions," the report says. "We do expect online shopping to rise as people become increasingly interested in reducing their exposure to others, as the virus appears to be spread via coughs and sneezes."

Other products beginning to see sales increases include air cleaners and air purifiers, sales of which rose 3% in the week ending Feb. 22.

The next possible product shortage? Hand and body lotion.

"Simply because an increased focus on hand washing and disinfecting will have a negative effect on skin," Nielsen says.

Follow USA TODAY reporter Mike Snider on Twitter: @MikeSnider.