A top scientist has warned that cloth sheet masks are not going to protect people from the fast-spreading covid-19 Delta variant.

During an interview with CNN on August 2, Michael Osterholm, Ph.D., epidemiologist, and director of the University of Minnesota Center for Infectious Disease Research and Policy, made the case that many of the face masks that are widely used aren’t up to snuff when it comes to preventing spreading or inhaling the microscopic aerosols that spread COVID-19.

Specifically, he said it was time for people to upgrade from the cloth masks, bandanas, and gators that do very little to protect against virus transmission.

“You know I wish we could get rid of the term masking because, in fact, it implies that anything you put in front of your face works, and if I could just add a nuance to that which hopefully doesn’t add more confusion is we know today that many of the face cloth coverings that people wear are not very effective in reducing any of the virus movement in or out,” he said.

To point out their ineffectiveness, Osterholm went on to cite an example of the smoke conditions created by wildfires in the Northwest that are currently blanketing parts of the U.S. “Either you’re breathing out or you’re breathing in and in fact if you’re in the upper Midwest right now anybody who’s wearing their face cloth covering can tell you they can smell all the smoke that we’re still getting.”

Instead, Osterholm argued that it was time for people to begin using the right type of mask that could properly slow the spread of the virus.

“We need to talk about better masking,” he argued.

“We need to talk about N95 respirators, which would do a lot for both people who are not yet vaccinated or are not previously infected. Protecting them as well as keeping others who might become infected having been vaccinated from breathing out the virus.”

Osterholm isn’t the first expert to advocate for upgrading PPE. During an appearance on CBS’ Face the Nation on July 25, Scott Gottlieb, MD, former Food&Drug Administration (FDA) commissioner, argued that the right quality mask was necessary to protect against a strain as contagious as the Delta variant.

“It’s not more airborne, and it’s not more likely to be permeable to a mask. So a mask can still be helpful,” Gottlieb told host John Dickerson.

“I think, though, if you’re going to consider wearing a mask, the quality of the mask does matter. So if you can get your hands on a KN95 mask or an N95 mask, that’s going to afford you a lot more protection.”

But while the right type of mask will go far to help stop the spread of COVID, Osterholm also bemoaned the current state of communication from officials, arguing that continuing to roll out shots to the public would be the best way to finally put an end to the pandemic.

“We’re in a very unfortunate situation, [and] we’ve really brought this country to a point of confusion which really misses the main point that we should be focusing on vaccine, vaccine, vaccine,” he argued.