Pro and anti-mask advocates battled on Twitter after New York Times columnist Bret Stephens covered a recent study that concluded masking made "no difference" on the spread of COVID.

The op-ed, headlined, "The Mask Mandates Did Nothing. Will Any Lessons Be Learned?" examined whether masks made a real difference in preventing transmission of the virus.

Oxford epidemiologist Tom Jefferson concluded the science was clear. 

FACE MASKS MADE ‘LITTLE TO NO DIFFERENCE’ IN PREVENTING SPREAD OF COVID, SCIENTIFIC REVIEW FINDS

"There is just no evidence that [masks]," Jefferson reportedly said, "make any difference." 

"Full stop," Jefferson emphasized. 

The op-ed ignited a flame war on Twitter, with some conservative political commentators declaring vindication on claims that some of them have been making since early 2020. One pro-mask advocate cursed out the New York Times columnist, with another scientist calling some of the discussion around mask mandates "misinformation." 

"While it’s nice to see the NY Times finally admit masks are worthless, it’s false to say the mandates ‘did nothing,’" Babylon Bee CEO Seth Dillon wrote. 

"They harmed kids, eroded public trust, and psychologically damaged millions of people to the point where they’re still afraid to breathe in public."

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"Natural immunity is as good as vaccinated immunity. Now, masks are ‘worthless.’ I'm old enough to remember when I was smeared as spreading 'misinformation' for saying the same things years ago," podcast host Kyle Becker tweeted in response to Stephens’ op-ed. 

Author David Zweig pointed out that the study on masking, published in collaboration with prestigious nonprofit Cochrane, was only allowed oxygen in the op-ed section of The Times.

"The remarkable thing here is that the only way the most prestigious data review on community masks - which found no clear evidence of benefit - made it into the paper of record was in an opinion piece The NYT Science desk did not deem it newsworthy." 

Poker commentator Joe Stapleton targeted Stephens directly, calling him a "conservative a--hat." 

"An opinion piece in the New York Times by noted conservative a--hat Bret Stephens saying masks don't work isn't the same as the New York Times saying masks don't work."

Mask advocate and Columbia University Irving Medical Center scientist Dr. Lucky Tran claimed that "misinformation" was growing online in a series of tweets published the same day as Stephens' column. 

"There's a lot of disinformation claiming ‘mask mandates don't work on the population level.’ These lies ignore the nuance: even when broad mask mandates were in effect, COVID was being spread in social spaces and at home when masks came off."

Dr. Tran argued that masking did "help flatten the curve during surges." 

PARENTS NOW QUESTION WHETHER COVID MASK MANDATES DID MORE HARM THAN GOOD

Jefferson, on the other hand, said that the evidence was conclusive. Even N-95 masks made "no difference" on the spread of COVID. His study, the scientist explained, were based on randomized trials, the gold standard in scientific exploration. 

The studies that convinced government leaders to adopt mask mandates were "non-randomized studies, flawed observational studies," Jefferson reportedly said.