TORONTO -- Face masks, originally seen as unnecessary outside hospitals and now facing global shortages, could be re-emerging as a new normal for daily life during the coronavirus pandemic.

As the crisis evolves daily, so does expert guidance, but there has been much mixed messaging around face masks in particular.

The White House recently signalled that the U.S. Centers for Disease Control and Prevention would be issuing new guidance in the coming days and recommending the widespread use of face masks.

But in a tweet Saturday, the CDC denied such claims. Currently, the group recommends only health care professionals and people who have COVID-19 and are showing symptoms wear a face mask. You do not need to wear a face mask in your own home.

“CDC does not recommend that people who are well wear a facemask (sic) to protect themselves from respiratory illnesses, including COVID-19,” reads the center’s FAQ page for the virus.

The Public Health Agency of Canada currently provides the same messaging for Canadians: If you're healthy, you don't need a mask to prevent the spread. "Wearing a mask when you are not ill may give a false sense of security," the agency says online, adding that there are risks associated with masks: they need to be changed frequently and improper disposal could increase infection risk.

It's a message that Chief Public Health Officer Dr. Theresa Tam reiterated in a press conference on Monday.

"What we worry about is actually the potential negative aspects of wearing a mask, where people are not protecting their eyes or other aspects of where the virus could enter your body, and that gives you a false sense of confidence," Tam said.

"But also, it increases the touching of your face. If you think about it, if you've got a mask around your face sometimes you can't help it."

Last week, Health Canada released a warning about homemade masks, advising Canadians that they should be used with caution and have several limitations that surgical masks and respirators do not. Homemade masks have not been tested “to recognized standards.” They may not provide “complete protection” against viruses. They may be difficult to breathe through and made with ineffective fabric. They may also be loose-fitting and require frequent adjustments that would increase hand-to-face contact.

“Homemade masks are not medical devices and consequently are not regulated, like medical masks and respirators,” the agency wrote. “These types of masks may not be effective in blocking virus particles that may be transmitted by coughing, sneezing or certain medical procedures. They do not provide complete protection from the coronavirus because of a potential loose fit and the materials used.”

Meanwhile, other experts have started to suggest more widespread use of the protective gear. On Sunday, infectious disease specialist Dr. Abdu Sharkawy told CTV National News that he wears a mask whenever he’s out in public and could come in contact with other people.

WHEN TO WEAR A MASK

“The simple answer is if you are going to be anywhere near contact with someone else—especially not within your nuclear household—it’s a good idea to wear a mask,” he said, emphasizing that Canadians should not be interacting in-person with anyone who doesn’t live in their home.

If you decide to go for a walk, it’s “not a bad idea” to wear a mask, but you shouldn’t have to: “You shouldn’t be going for walks with anyone except the people within your own nuclear household,” he said.

The grocery store is a different story. While many have instituted precautions—from new capacity rules to plexiglass barriers at registers—it’s difficult to control other people’s adherence to physical distancing.

“It’s going to be nearly impossible to maintain a distance of six feet at all times,” said Sharkawy. “If you’re going to the grocery store to pick up your groceries for the week, you should be wearing a mask.”

At home, masks are not necessary, he added.

“You’re in the same environment as everybody else (at home). You’re breathing the same air. If you go outside your front door, you don’t need a mask,” he said. “But if you’re out in public and anywhere near exposure with other people not within your nuclear household, you should ideally wear a mask.”

GLOBAL SHORTAGES

Despite the suggestion that more people wear facial protection, there are escalating shortages of medical supplies, including face masks, around the world.

There have been reports of hospitals even rationing masks, limiting staff to one or two per day. To help leave more masks for the front-line workers and patients, there have been an increasing number of charitable efforts around the world, with groups donating thousands of masks to hospitals, including the stockpiles of the Bank of China and prop masks from the set of Grey’s Anatomy.

Last week, a Toronto hospital appealed for volunteers to help sew 1,000 new surgical masks every week for visitors and discharged patients, citing the “worldwide shortage of personal protective equipment.” Even this effort came with a call for more people to wear masks in public.

“We want to see all east enders (in Toronto) wearing a fabric mask when they need to be within six feet of other people, especially vulnerable populations and the elderly,” wrote Dr. Jeff Powis, of the Michael Garron Hospital, in a news release.

WHAT TYPE OF MASK?

While there is evidence to suggest that only N95 respirator masks, which have built-in filters, are effective at protecting the wearer from harmful particles, Dr. Sharkawy told CTV National News that there is enough evidence to suggest even makeshift masks will suffice, though they won’t necessarily prevent the wearer from getting sick.

“Anything that covers your nose and your mouth with a reasonable seal. You can fashion out of cloth, you can fashion even out of a vacuum bag,” he said. “As long as it can stand a little bit of humidity, that’s very useful. If it’s something that’s reusable that’s cloth that can be washed, that’s also very reasonable.”

Still, face masks should not be used as a substitute for the more vital precautions like frequent hand washing and staying at home. Sharkawy himself wears a mask outside when he may be in contact with others, but the safety measures don’t stop there.

“I’m taking exceedingly strict precautions in terms of hand washing regularly,” he said, “and physically distancing absolutely at all times.”

With files from CTV News' Rachel Gilmore.