Large Randomized Trial Shows Masks Offer Little Protection Against Virus

A groundbreaking randomized controlled trial of  4,862 participants found that surgical masks in public offer virtually no protection against the SARS-CoV-2 virus.

The study by Danish researchers published on November 18 in Annals of Internal Medicine randomly assigned 3,030 to wear masks outside the home for a two-month period in Denmark, April, and May. The researchers assigned 2,994 to a control group. All participants were adults who spent more than 3 hours outside in jobs that didn’t traditionally require masks. Mask wearers were given instruction on proper use and supplied with 50 masks.

Infection occurred in 42 participants in the mask group (1.8 percent)  and 53 (2.1 percent) in the group that did not wear masks.

“The recommendation to wear surgical masks to supplement other public health measures did not reduce the SARS-CoV-2 infection rate among wearers by more than 50 percent in a community with modest infection rates, some degree of social distancing, and uncommon general mask use,” stated the authors. “The data were compatible with lesser degrees of self-protection.”

The study made no assessment of whether masks can protect others.

Publication Catch-22

Governments around the world have been mandating masks since the seriousness of the novel coronavirus became clear earlier this year. The recent emergence of a second wave of the disease in Europe, and indications of a similar outbreak in the United States, are raising questions about how effective masks are in protecting people from infections.

Although pronouncements attesting to masks’ effectiveness have been commonplace, empirical evidence supporting the wearing of masks has been lacking. When the study was complete, the authors have had no success having it published in the Lancet, the New England Journal of Medicine, and the Journal of the American Medical Association.

Being turned down by the influential medical journals is not uncommon in the highly competitive world of medical science. But the authors, having broken new ground on a subject at the center of global public health concerns, believe their findings should see the light of day.

“They all said no,” Christian Torp-Pedersen, chief physician at North Zealand Hospital’s research department, who was involved in the study, told the Washington Examiner on October 22. “We cannot start discussing what they are dissatisfied with [parties outside the journals] because, in that case, we must also explain what the study showed, and we do not want to discuss that until it is published.”

“This is the world’s largest study of its kind and is expected to be included as an important factor in the basis for government decisions regarding the use of masks,” Bundgaard told the Examiner.

In a revealing exchange, Torp-Pedersen hinted the results may not support the wearing of masks. “Can one interpret a controversial research result in the sense that no significant effect of mask use is demonstrated in your study,” asked the Examiner, Torp-Pedersen replied, “I think that’s a very relevant question you are asking.”

Ineffective for Flu

Studies investigating the effectiveness of masks in curbing the transmission of infectious diseases have been published in recent years.

Those studies dealt with influenza, not coronavirus. As recently as July, the Centre for Evidence-Based Medicine at Oxford University published a paper showing “a recent crop of trials 9,112 participants to the randomized denominator of 13,259 and showed that masks alone have no significant effect in interrupting the spread of ILI (influenza-like illness) or influenza in the general population, nor in healthcare workers.”

A randomized control trial conducted in 2015 studying 1,607 Vietnamese health care workers cautioned against the use of cloth masks by such workers, stating “moisture retention, reuse of cloth masks, and poor filtration may result in [an]increased risk of infection.”

Although influenza and coronavirus are different diseases, they are transmitted in a similar fashion. Masks are not commonly worn, much less mandated, during the annual winter flu season in which tens of thousands of people in the United States die of the disease. This appears to be a reflection of the medical community’s view that they are of little utility in preventing the spread of flu.

UK Failure

British Prime Minister Boris Johnson’s October 31 announcement of a second nationwide COVID-19 lockdown was an acknowledgment the coronavirus had reemerged despite the mask mandates. Face masks have been as ubiquitous in the UK as in any other country, but the practice failed to stem the spread of the pandemic.

“COVID made the unfortunate leap from a public health issue to a political tool,” said Marilyn Singleton, M.D., J.D, a board-certified anesthesiologist in California and policy advisor to The Heartland Institute, which co-publishes Health Care News. “Political motivations have led to censorship of much-needed treatment options and have no place in scientific research.

“Initially, all of our experts discouraged community mask-wearing,” said Singleton. “Feeling desperate and powerless, many leaders’ quick answer to a complex problem is to ‘mask up’ and show you are a good person.”

‘False Sense of Security”

It is time to face reality and acknowledge masks are not the answer, says Singleton.

“The virus is airborne and infectious,” said Singleton. “Sixty-six percent of hospitalized COVID patients in New York had stayed at home. A recent CDC (U.S. Centers for Disease Control and Prevention) survey found that 71 percent of the people who tested positive for the SARS-CoV-2 virus ‘always’ wore masks, and another 14 percent often wore them.

“Masks give a false sense of security, and people may tend to ignore basic handwashing, coughing, and sneezing etiquette, and avoiding others if either party is sick,” said Singleton. “If there is evidence showing that community mask-wearing is the wrong path to help control the virus’ spread, health professionals can emphasize other measures.”

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

Internet info:

Henning Bundgaard, DMSc, Johan Skov Bundgaard, BSc, et al, “Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers,” Annals of Internal Medicine, November 18, 2020:  https://www.acpjournals.org/doi/10.7326/M20-6817