Pharmacies and health supply stores across the world are experiencing high demand for surgical face masks. | Patipat Janthong/Getty Images

The Centers for Disease Control and Prevention does not recommend wearing them in the US.

When Vivi Widyaningsih stopped by her local Target and CVS stores in Tallahassee, Florida, she was surprised to find that all surgical masks were out of stock. After all, there hadn’t been any cases of coronavirus in Florida.

Widyaningsih, who considers herself an overly cautious person, turned to Amazon and selected three masks to purchase the next morning, but two of them sold out overnight before she could buy.

“I got a cough after arriving home [from a conference in Boston], which was a result of the drastic weather change, but just to be safe, I wanted to get some masks,” Widyaningsih told Vox in a Twitter message. “My roommates were taking turns getting the flu, and I didn’t want to get infected.”

Although there have been only 11 confirmed cases of coronavirus in the US so far, people across the country have descended on local pharmacies or health supply stores to hoard boxes of surgical masks, even in states where there isn’t a serious coronavirus threat. Some say it’s a precaution, while others are looking to send masks to friends and relatives overseas, where supplies are low or expensive due to increased demand.

Smoke’em if you got em. Anecdotal evidence of an abrupt surge in mask buying. This is from a CVS in rural Virginia pic.twitter.com/gPhy0OVxuW — Shelt Garner (@sheltgarner) February 1, 2020

In Wuhan, China, the center of the outbreak, face masks were made mandatory in late January. As of February 4, the number of coronavirus infections has surpassed 24,000 (with a vast majority of cases in mainland China), and 494 people have died. Yet the risk of contracting the disease domestically in the US is still “quite low,” according to the Department of Health and Human Services.

HHS Secretary Alex Azar told the New York Times that it’s “unnecessary” for Americans to buy masks. The Centers for Disease Control and Prevention (CDC) doesn’t recommend it either. Most health experts Vox has spoken to have said there’s no good evidence to support the use of face masks for preventing this disease in the general population.

“If someone has a respiratory infection, masks are helpful at stopping spread,” Isaac Bogoch, an infectious disease specialist and professor at the University of Toronto, told Vox’s Julia Belluz. “But if people are uninfected wearing a little flimsy mask, it is not going to significantly reduce their risk of acquiring this infection.”

Wearing a mask can also appear “overly alarmist,” Bogoch added.

“But if people are uninfected wearing a little flimsy mask, it is not going to significantly reduce their risk of acquiring this infection”

In other words, though masks can help prevent the spread of disease by sick people in public places, most people in the US aren’t even infected with the coronavirus at this point. But that hasn’t stopped shoppers in the US and other countries from panic purchasing them en masse. Popular mask sellers on Amazon are completely sold out, and some are even warning customers of counterfeit masks.

People typically gravitate to standard surgical masks, which basically look like blue-hued paper rectangles. But some have sought out N95 respirators, a circular cup-like mask generally used by health care workers.

Walgreens and Duane Reade pharmacies have seen increased demand in products like face masks and hand sanitizer, a spokesperson confirmed to Vox in an email. On Twitter, users are posting photos of empty store shelves and marked-up prices of face masks online, reminding others not to hoard supplies.

Please do not hoard n95 masks or even surgical masks. Doctors and other health professionals who are at the frontlines of various epidemics and diseases need them more. If you have more than you really need, please donate them to hospitals that need them most — Marvic Leonen (@marvicleonen) January 31, 2020

The demand for masks has skyrocketed, especially in Asian countries closer to the epidemic, prompting friends and family overseas to buy and ship masks to the US. Religious organizations, including the Church of Jesus Christ of Latter-day Saints and the Vatican, have donated thousands of respirator masks and health supplies to Chinese provinces impacted by the disease.

People in East Asian countries, including some immigrants in the US, have a predilection for wearing face masks in public to shield against smog (or, more generally, germs), even when they aren’t necessarily sick.

ALSO. IF YOU SEE ASIANS WEARING FACE MASKS, IT MAY NOT MEAN THEY’RE SICK. IT IS A CONSCIENTIOUS CULTURE. WE WEAR IT AS A PREVENTATIVE FOR OURSELVES TO LIMIT GETTING OR SPREADING ILLNESS. WE DON’T START WEARING NOT AFTER THE FACT. SO DON’T BE AN ASSHOLE WHEN YOU SEE US WEAR IT. — Ren Fernández-Kim (@CorpusRen) February 1, 2020

Aiko Paltrowitz, a program manager in San Francisco, told Vox on Twitter that she initially planned to ship boxes of surgical masks to her Japanese friends, given how quickly masks were selling out in Japan. Drug stores in Tokyo have stocked up on masks, only to sell out within hours of opening.

“It’s causing a huge problem for locals in Japan that they can’t find a mask anywhere, and even if they do, masks are being sold via auction sites or online stores at an unreasonable price, like $100 for one,” Paltrowitz said.

When she visited her local Walgreens to buy some, a clerk told her that every store in the San Francisco area was out of masks. Paltrowitz thinks that other people, at least in San Francisco, have the same intentions when it comes to buying masks: to send them overseas.

Some experts worry that this sudden spike in demand might create a shortage for workers in the health care industry who are at the front lines of treating patients. The CDC is currently communicating with manufacturers to prevent the possibility of shortages, the New York Times reported.

If the coronavirus outbreak continues, however, mask manufacturing overseas could be disrupted. Most surgical masks and respirators are produced outside of the US, which means supply chains could be vulnerable if a global pandemic breaks out, Wired reported.

This all depends on how much longer the outbreak poses a threat, both in China and beyond. For now, the spread of the Wuhan coronavirus in the US isn’t a major risk, so a face mask is unlikely to protect you from anything at all.

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