According to Sweden’s top infectious disease expert, masks may not be effective at stemming the spread of COVID-19, and can even be more harmful than helpful as users tend to use masks as a crutch and avoid other measures that may be more effective because they feel secure in the masks.
The U.S. Centers for Disease Control and Prevention (CDC) has thrown its entire weight behind mask wearing to stop the spread of COVID-19, recommending that people wear masks any time they are with people outside of their home and when social-distancing measures are difficult to maintain. They even suggest wearing masks when it is possible to maintain a six-foot distance from others.
But Anders Tegnell, chief epidemiologist at Sweden’s Public Health Agency, notes there is little evidence that masks are effective, citing Sweden’s success in slowing the spread of the virus without the use of masks.
“With numbers diminishing very quickly in Sweden, we see no point in wearing a face mask in Sweden, not even on public transport,” said Tegnell, as reported by Fortune. “That Sweden has come down to these levels is very promising,” Tegnell told reporters in Stockholm last month. “The curves are going down and the curves for the seriously ill are beginning to approach zero.”
Tegnell contends it is possible mask wearing can even be harmful in that they may encourage other more harmful behaviors. “It is very dangerous to believe face masks would change the game when it comes to COVID-19,” Tengell said, according to the Financial Times. “Face masks can be a complement to other things when other things are safely in place,” he said. “But to start with having face masks and then think you can crowd your buses or your shopping malls — that’s definitely a mistake.”
Tegnell is not alone in this assessment. According to one of Holland’s top scientists, masks provide the wearers with a false sense of security, thereby deterring them from engaging in other, more proven methods for stemming the spread of COVID-19.
“The evidence for [masks] is contradictory,” said Christian Hoebe, a professor of infectious diseases in Maastricht. “In general, we think you must be careful with face masks because they can give a false sense of security. People think they’re immune from disease or stop social distancing. That is very negative.”
This sentiment was echoed by Coen Berends, a spokesman for the National Institute for Public Health and the Environment in the Netherlands. “Face masks in public places are not necessary, based on all the current evidence,” said Berends. “There is no benefit and there may even be negative impact.”
The efficacy of masks is not settled science, but the few rigorous studies that have been done have shown masks to be ineffective at stopping viruses. According to the first randomized clinical trial studying the effectiveness of cloth masks, published in April in the journal BMJ Open, individuals who wore cloth masks had significantly higher rates of respiratory infection than those who wore medical masks. The authors of the study suggested it was likely the cloth masks were problematic because they retained moisture retention and had poor filtration.
The California Globe also observed that extensive randomized control trial (RCT) studies and meta analysis reviews of those studies have shown that masks and respirators are ineffective against the spread of influenza-like illnesses and respiratory illnesses believed to be spread by droplet and aerosol particles. The Globe cited 10 separate studies showed wearing masks do not reduce the rate of influenza infections. A pool analysis of 10 “randomized controlled tests” (RCTs) by the Center for Disease Control found “no significant reduction in influenza transmission with the use of face masks.”
“There is limited evidence for their [masks] effectiveness in preventing influenza virus transmission,” they found. This applied to masks “worn by the infected person for source control OR when worn by uninfected persons.” They unambiguously concluded that there was “no significant effect of face masks on transmission of laboratory-confirmed influenza.”
Denis G. Rancourt, Ph.D., explains the science behind this:
It would be a paradox if masks and respirators worked, given what we know about viral respiratory diseases: The main transmission path is long-residence-time aerosol particles (< 2.5 μm), which are too fine to be blocked, and the minimum-infective dose is smaller than one aerosol particle.
The Daily Mail reports the World Health Organization even initially voiced skepticism over the widespread use of masks by healthy people, admitting it has not yet been supported by “high quality or direct scientific evidence,” before changing its tune in June.
Meanwhile, Tegnell told the U.K. Times he was astonished at the lack of studies examining the effectiveness of masks, but that it was telling that countries with overwhelming mask compliance continue to see increases in transmission.
According to Fortune, “Tegnell has consistently argued that Sweden’s approach is more sustainable than the sudden lockdowns imposed elsewhere. With the risk that Covid-19 might be around for years, he says completely shutting down society isn’t a long-term option.”
Tegnell notes the second waves being seen in countries with mask compliance are “worrying” and underscore his stance.
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