Studies Have Yet to Show Face Masks Protect Public from COVID-19

Responding to omicron, the latest COVID-19 variant, some public officials and private employers have imposed or reimposed mandated masking to help stem the disease’s transmission.

“Yet evidence of facemask efficacy is based primarily on observational studies that are subject to confounding and on mechanistic studies that rely on surrogate endpoints (such as droplet dispersion) as proxies for disease transmission,” write Ian T. Liu, Vinay Prasad, and Jonathan J. Darrow in “Evidence for Community Cloth Face Masking to Limit the Spread of SARS‐​CoV‑2: A Critical Review,” a working paper published by the Cato Institute on November 8, 2021.

“The available clinical evidence of facemask efficacy is of low quality and the best available clinical evidence has mostly failed to show efficacy, with 14 of 16 identified randomized controlled trials comparing face masks to no mask controls failing to find statistically significant benefit in the intent-to-treat populations,” write the authors.

Doubts Raised Before Pandemic

Prior to the pandemic, there was scant evidence that masking—“at least as commonly practiced in the United States, using cloth masks—is effective at suppressing various types of respiratory infection,” the authors write.

They note that in the surgical operating room context, a review by the Cochrane Collaboration—a nonprofit that provides comprehensive summaries of evidence on various medical topics—found “no statistically significant difference in infection rates between the masked and unmasked group in any of the trials.”

A Cochrane review of masking and influenza-like illness found “that wearing a mask may make little or no difference to the outcome of influenza-like illness … compared to not wearing a mask,” write the Cato authors.

WHO Was Skeptical?

The World Health Organization (WHO) was initially skeptical about the usefulness of having the public wear cloth masks to stem the spread of the coronavirus. The WHO’s initial COVID-19 guidelines stated that “cloth (e.g., cotton or gauze) are not recommended under any circumstance.” In a subsequent update, the WHO noted “the widespread use of masks by healthy people is not yet supported by high quality or direct scientific evidence.”

Nevertheless, by September 2020, the U.S. government had distributed 600 million facemasks to the public, and 32 states and numerous municipalities implemented local mask mandates at some point.

New York City slapped a $1,000 fine on those refusing to wear a mask in public, and presidential candidate Joe Biden declared in a speech, “Wearing a mask is not a political statement, it is a scientific imperative.”

Little Evidence Masks Effective

There is a widespread misconception infectious particles are primarily emitted during forceful expiration such as sneezing, but little evidence frequent public sneezing has led to the spread of the virus, write the authors.

Larger “droplets” (greater than 10 micrometers) and smaller “aerosols” containing the virus are more infectious.

“The greater the role of aerosols in spreading SARS-CoV-2, the less important is the filtering capability of masks, because exhaled air easily flows around a mask’s edges,” the authors of the Cato paper write in a summary of their findings in the journal Regulation (Winter 2021-2022). “The extent to which droplets penetrate a mask has not been established as a reliable surrogate for the prevention of disease transmission.”

Randomized Controlled Trials?

The best evidence of masks’ effectiveness would be from cluster-random-controlled trials (RCTs) showing individuals wearing cloth masks have lower viral spread than those not wearing cloth masks, with high participation and adherence to protocols, write the Cato authors.

“The only two sizeable studies evaluating masks in the context of COVID-19 failed to demonstrate statistically significant reductions in confirmed viral transmission either for surgical masks (one study) or for cloth masks (the other study),” they write.

Others have expressed doubts about the wisdom of mandatory masking. “Many schools force children to wear masks, contrary to very clear science and simple logic,” writes Scott Atlas, M.D., a radiologist, and former Trump administration health care adviser, in A Plague Upon Our House: My Fight at the Trump White House to Stop COVID from Destroying America. “Must we prove that the earth is round again?” Atlas writes.

‘Preconceived Notions’

“More than a century after the 1918 influenza pandemic, examination of the efficacy of cloth masks has produced a large volume of mostly low-quality evidence that has generally failed to demonstrate their value in most settings,” write the Cato authors in Regulation.

 “When repeated attempts are undertaken to demonstrate an expected or desired outcome, there is the risk of declaring the effort resolved once results consistent with preconceived notions are generated, regardless of the number and extent of previous failures,” write the Cato authors.

Masking is an instrument of political control and does nothing to protect public health, Joel S. Hirschhorn, author of Pandemic Blunder: Fauci and Public Health Blocked Early Home COVID Treatment, told Health Care News.

“I have been firmly convinced during the pandemic that there is no reliable scientific basis for believing that masking is an effective contagion-control measure,” said Hirschhorn. “Masking is used by incompetent public health officials to control lives, not to protect lives. From the earliest days of the pandemic, there were reliable test data showing the ineffectiveness of masking.  It continues as political action, not as a needed or sensible public health strategy.”

Chad Savage, M.D., founder of YourChoice Direct Care and policy advisor to The Heartland Institute, which publishes Health Care News concurs.  

“Despite the lack of substantial, quality evidence of mask efficacy, many continue to push for broad masking,” said Savage. “This is likely due to the need to do ‘something’ against a scary contagion. For to admit the lack of mask-efficacy is to deprive oneself of the perception of a nidus of control and the concept that we may have no agency is beyond many to accept no matter the evidence.”

Bonner R. Cohen, Ph.D. (bcohen@nationalcenter.org) is a senior fellow at the National Center for Public Policy Research.