The use of face masks is “absolutely fundamental” to controlling the spread of the coronavirus, according to Dr. William Schaffner, M.D., a professor of medicine at the Division of Infectious Diseases at Vanderbilt University and the medical director of the National Foundation for Infectious Diseases.

“The face mask is absolutely fundamental to controlling this infection,” Schaffner told SiriusXM host Rebecca Mansour on Tuesday’s edition of Breitbart News Tonight.

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Schaffner explained that the Centers for Disease Control and Prevention (CDC) changed its original guidance against face masks after learning that the coronavirus is easily transmitted by asymptomatic spreaders.

“Why did they change their recommendations about wearing masks? They changed it because they discovered that there could be many people who are infected with this virus who don’t get sick, but can nonetheless transmit the virus. They can be stealth spreaders,” Schaffner said.

“If we’re trying to interrupt the spread of this virus, there are only a couple of things we can do,” he explained. “Number one, put a mask on everybody, because here I am, feeling perfectly well speaking with you, but I could be infected. So, if we were within three feet of each other having this conversation, the only way you can be protected then, even though I’m healthy, is for me to wear a mask. Of course, I don’t know if you’re infected either. So you better wear a mask so I’m protected. So that’s the reason everybody should be wearing a mask.”

“The next thing is the six-foot rule, as it were, the eleventh commandment, thou shalt not get closer than six feet with anybody,” Schaffner quipped. “The reason for that is, most of the transmission of this virus occurs within that six feet.”

When it comes to reopening the country, “the trick is to do this carefully and slowly,” said Schaffner. “What do I mean, ‘carefully’? Let’s open up, but all wear masks. Let’s open up and keep distance from each other. Let’s not go out to crowded events at the present time. We can’t go back to the way it was. Time marches on. We’re going to a new normal.”

A 2012 epidemiological study provided evidence that wearing face masks significantly reduce the transmission of influenza-like illnesses, Schaffner noted.

“There’s actually one study like that done by Dr. Arnold Monto at the University of Michigan School of Public Health among students, and obviously he couldn’t enforce the wearing of the face mask day in and day out, but he did have one group of students wear face masks generally during the flu season and another group not. And influenza-like illness was substantially less in the face mask group than in the non-face mask group,” Schaffner said.

Schaffner noted that the subjects of the study used “a simple surgical face mask, not the cumbersome tight N95 respirators.”

All manner of face masks are effective in reducing the transmission of influenza-like illnesses, he explained. “Masks, no matter what they are — bandanas, homemade masks, even the rather fragile-looking surgical masks — are really rather effective in preventing any infection you may have from going to someone else,” he said.

Schaffner again reminded listeners that the main reason for wearing a mask is to prevent the spread of the virus by asymptomatic carriers. “I wear a mask to protect you. You wear a mask to protect me,” he said.

Mansour inquired about the issue of “excess deaths” and how COVID-19 is determined to be a cause of death among persons with comorbidities.

“The ‘excess death’ concept was established with the influenza,” explained Schaffner. “We know approximately by season how many people die of which illnesses, and then during influenza season you get a big spike in deaths that go up due to pneumonia and influenza, and then the curve comes down again as influenza goes away, but there’s no dip below the curve. You see, if influenza had killed people in advance — they were so chronically ill — of when they normally would have died, then after the epidemic there would have been people who had been carried away earlier, so the death rate would have gone down.”

Schaffner continued, “This is a little complicated. So those deaths are called ‘excess deaths,’ and like with COVID, there’s been an increase in unexpected deaths if you look at them statistically, and they’re called the excess. Those are the excess unexpected deaths likely caused by COVID or certainly influenced by COVID.”

Schaffner added, “There are a lot of people in the country who have chronic underlying illnesses of the liver, or the kidney, [or] had diabetes. Along comes COVID, and it pushes them over the edge as they’re in the hospital. The doctors can see that their liver function, their kidney function, [or] their diabetes went way out of whack because of the COVID infection. The doctor might just write down ‘death due to liver disease’ because the patient was already predisposed to die, because he had such impaired organ function already.”

“If you look at it from a public health perspective, it’s clear that many people with these illnesses in other seasons of the year would have continued to survive,” Schaffner explained. “Then either you put in influenza — or now you put in COVID — and all of a sudden a lot of these people are dying of these illnesses, clearly pushed over the edge, so to speak, by COVID or by influenza. And so that’s why these deaths are called ‘excess.'”

Schaffer went on, “These infectious agents come into our communities and — oh, terrible word — ‘harvest’ the people who are most fail who are already impaired, are chronically ill, and they are carried away by COVID or influenza. These are people that we always term as the most vulnerable. They’re the people we’re most concerned about when these infections come into our communities.”

Mansour asked about the accuracy of death count estimates attributed to COVID-19.

“The [death] numbers come from the diagnoses that the attending physicians make on death certificates,” Schaffner said. “And those death certificate diagnoses vary in specificity. If the doctor knew that the person had a positive COVID test, they likely would have written down ‘COVID,’ but not necessarily, because the end of life might have been due to pneumonia and the doctor might have just chosen to write down ‘pneumonia,’ or ‘sepsis,’ or some other diagnosis.”

A person’s cause of death cannot always be precisely determined, explained Schaffner. He concurred with Dr. Anthony Fauci’s appraisal that the number of deaths attributable to COVID-19 is likely higher than John Hopkins University’s estimate of 80,000.

“Death certificate diagnoses are not as precise as the public would be led to believe,” Schaffner noted, “and just as Dr. Fauci said, particularly early in the epidemic when there wasn’t a lot of testing, people died of pneumonia or influenza-like illnesses that couldn’t be diagnosed as COVID.”

Schaffner concluded, “I agree with Dr. Fauci. I don’t know how many more deaths were caused by COVID, but surely more were, and I think every infectious disease doctor in the country would agree with that.”

Breitbart News Tonight broadcasts live on SiriusXM Patriot channel 125 weeknights from 9:00 p.m. to midnight Eastern or 6:00 p.m. to 9:00 p.m. Pacific.

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