"We know that the virus can be transmitted by what we call air assaults, its the tiniest of particles. If anything comes in along the side of the mask or escapes that way, then it really minimizes both to protection for the individual who used the mask or the protection for others so that if I'm infected, I don't transmit to them. That's when you get into the surgical masks and to the cloth masks. And quite honestly, the data for both is lacking that they are major impediments, and he's getting infected or infecting others."
Osterholm does say that the popular N95 masks used by frontline healthcare workers are very important in helping the fight against coronavirus.
"The N95 respirator. The thing that fits very tight on your face, the air actually passes through the material. The matrix materials are actually a cord material and that hardens and the virus is trapped when it goes through there, and it doesn't leak in along the side of the face. Those are the kinds of masks that we need for health care workers, first responders that are taking care of ill patients how to protect them. These are very important."
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For most consumers, and even some frontline healthcare workers, N95 masks aren't available and they are only left with surgical masks. Dr. Osterholm says that those are better than nothing.
"People want to wear a mask. That's great. But I think we're going to show in the end that many more health care workers were infected by working with only surgical masks and not N95 [masks]. I realize and understand the shortage of N95. I get that [surgical masks] are better than nothing, but I don't think that it offers anywhere near the protection that we need for this virus.
"The next time you see the sunlight, peer through your room in your home and you see all that dust floating there, that's an air assault. When you and I just talk, we create those."
"Cloth masks, I think are at the very bottom of the list. They have little impact if any. But they've become basically something that people feel like they have to do or want to do it. If they want to do it, go ahead."
In many areas, though, it's no longer a matter of whether you want to do it or not. In Michigan, masks are mandatory in any public place, including grocery stores. The mayor of Stillwater, Okla., rescinded a mask order after it was discovered that employees trying to enforce it were threatened with physical violence.
Dr. Osterholm ended his discussion about masks on The Morning News with Dave Lee by saying they just aren't that helpful in normal public places.
"I can tell you right now I don't believe that they play any major role in either preventing me from getting infected if I use it or if I am infected and don't know it. I don't have any symptoms. They don't protect those around me from using it."