American Federation of Teachers (AFT) President Randi Weingarten pushed for universal masking in schools during an interview with CNN on Monday, arguing it's the safest way to keep schools open this fall.

"We see the Delta variant be very transmissible," Weingarten said. "Masks stop transmission, so universal masking is going to be very helpful to keep kids safe, to keep the unvaccinated safe, and to keep schools open."  

The AFT leader said that she personally "hates" masks because she's asthmatic, but suggested it's a necessary burden.

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Critics questioned Weingarten's claim that masks stop the transmission of the virus, while hitting anchor Jim Sciutto for not pushing back on her assessment. 

Studies, such as those from The Lancet Digital Health, have shown that widespread use of face masks can help to prevent large outbreaks of COVID-19. But the authors noted study limitations, notably that they didn't account for contact tracing and testing and participants were asked to self-report their mask-wearing habits. 

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New York Post columnist Karol Markowicz ripped leaders for pushing for masking for children in a new op-ed, arguing that the U.S. needs to "stop listening to unhinged bureaucrats and journalists who frame children as little disease vectors." 

"There’s a reason much of Europe didn’t mask kids under age 12 at all," she wrote. "It isn’t that they care about their kids less than we do, here in a country that starts masking at the insane age of 2. In fact, it shows Europeans care about their kids’ development so much they won’t force them to play bit parts in a grand psychodrama."

Fox News contributor Dr. Marc Siegel agreed with most health professionals that masks have benefits, but he worried that forcing schoolchildren to wear cloth coverings all day could lead to socialization problems, rashes, anxiety, and other negative outcomes.

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"I think the schools should be focused more on vaccinating all teachers and staff and vaccinating kids that are over the age of 12, and under the age of 12, test them frequently and recommend masks, not mandate them," Siegel told Fox News Digital last month.

Weingarten also told MSNBC last week "we’re going to try" to get schools reopened in the fall, in what appeared to be a backtrack from comments she made in May that "we can and we must reopen schools in the fall." 

Her comments came after the Centers for Disease Control and Prevention reversed guidance on masks following the spread of the new Delta variant of the virus, declaring that vaccinated people should return to wearing masks indoors and suggesting universal masking in schools. Weingarten called it a "curveball." She has also previously claimed that her union has always tried to get schools reopened, but she and other teachers union leaders dragged their feet on getting kids back to the classroom, despite consistent data showing limited COVID spread among children in schools.

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Emails obtained by the New York Post revealed that the AFT influenced the CDC to alter its guidance on reopening. The agency had been prepared to allow in-classroom learning regardless of transmission rates, but at the suggestion of the union, the guidelines were adjusted to include a provision that said, "In the event of high community-transmission results from a new variant of SARS-CoV-2, a new update of these guidelines may be necessary."

The unions, critics say, were the biggest obstacle to in-person learning.

Compounded with her latest comments on masks, Weingarten's critics are running out of patience. 

"I try not to hate anybody but this woman has done more damage to America's children than any other single figure and it's infuriating," wrote American Spectator's Melissa MacKenzie. "She would create a nation of idiots in search of perfect safety to save teachers from having to do their jobs."

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