Sen. Rand Paul’s false claim that masks don’t work against the coronavirus gets Four Pinocchios from The Washington Post

Washington Post graphic
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By Salvador Rizzo
The Washington Post

“When you talk about the peer-reviewed studies of masks, there was one done in Denmark, showed that it didn’t work. When you look at all of Sweden — 1.8 million children have not been wearing masks for the last two years, they’ve had zero covid deaths. And you say, ‘Well, have the teachers been infected?’ Well, it turns out the teachers are infected at the same rate as the rest of the public. So, they’ve had no masks for a year, year and a half. And it has worked. And that’s a whole country.” — Sen. Rand Paul (R-Ky.), in an interview on Fox News, Nov. 29, 2021

When Paul talks about “the peer-reviewed studies of masks,” he is referring to only one study, from Denmark, and he’s twisting what it says. In reality, multiple peer-reviewed studies show that wearing face coverings mitigates the spread of the coronavirus.

That’s especially true for recently infected people who don masks when they go outside the home. They may not be showing symptoms, but they are carrying a high viral load. The face covering works as a stopper, capturing many infectious airborne particles before they can reach another person.

Although Sweden has seen a very low rate of child mortality from Covid-19, Paul’s statement that no Swedish children have died of the disease also is inaccurate.

The Facts

From April to June 2020, researchers tracked 6,024 participants for a study in Denmark, which did not recommend mask-wearing in public at the time. Cafes and restaurants were closed during most of this period; public health authorities were recommending quarantine for those with the coronavirus, as well as social distancing and limiting face-to-face encounters.

The study, published in the Annals of Internal Medicine last year, found that the group wearing surgical masks was less likely to catch the virus than the unmasked group, but there was not enough evidence to reach a statistically significant conclusion.

“Our results suggest that the recommendation to wear a surgical mask when outside the home among others did not reduce, at conventional levels of statistical significance, the incidence of SARS-CoV-2 infection in mask wearers in a setting where social distancing and other public health measures were in effect, mask recommendations were not among those measures, and community use of masks was uncommon,” the researchers wrote. “Yet, the findings were inconclusive and cannot definitively exclude a 46% reduction to a 23% increase in infection of mask wearers in such a setting. It is important to emphasize that this trial did not address the effects of masks as source control or as protection in settings where social distancing and other public health measures are not in effect.”

Paul claimed on Fox News that this study showed that masks don’t work, but in fact the study says masks could reduce coronavirus cases by up to 46 percent in circumstances like Denmark’s — or increase infections by up to 23 percent. A spokeswoman for the senator referred us to the Danish study but did not respond to our questions.

“Measures to impede transmission in health care and community settings are essential,” the same study adds. “The virus is transmitted person-to-person, primarily through the mouth, nose, or eyes via respiratory droplets, aerosols, or fomites. … Face masks are a plausible means to reduce transmission of respiratory viruses by minimizing the risk that respiratory droplets will reach wearers’ nasal or oral mucosa.” (Somehow this passage did not make it into Paul’s summary of the study.)

Other studies have found that mask-wearing in the community reduces the incidence of covid-19. Paul didn’t mention them on Fox News.

“During the pandemic, the scientific evidence has increased,” according to a study this year in the Journal of the American Medical Association (JAMA). “Compelling data now demonstrate that community mask-wearing is an effective nonpharmacologic intervention to reduce the spread of this infection, especially as source control to prevent spread from infected persons, but also as protection to reduce wearers’ exposure to infection.”

In the British Medical Journal last month, a review of six scientific studies found a 53 percent reduction in covid-19 incidence from mask-wearing. It added that the “results of additional studies that assessed mask-wearing (not included in the meta-analysis because of substantial differences in the assessed outcomes) indicate a reduction in Covid-19 incidence, SARS-CoV-2 transmission, and covid-19 mortality. Specifically, a natural experiment across 200 countries showed 45.7% fewer Covid-19 related mortality in countries where mask-wearing was mandatory.”

Research published in the Proceedings of the National Academy of Sciences (PNAS) in January found “evidence in favor of widespread mask use as source control to reduce community transmission.”

“Nonmedical masks use materials that obstruct particles of the necessary size; people are most infectious in the initial period post-infection, where it is common to have few or no symptoms; nonmedical masks have been effective in reducing transmission of respiratory viruses; and places and time periods where mask usage is required or widespread have shown substantially lower community transmission,” the survey says.

The lead author, Jeremy Howard, said the Danish research Paul was referring to “showed that low-quality masks such as cloth masks do not have a very large protective effect to the wearer.”

“This was expected — respiratory particles quickly evaporate and become too small for a cloth mask to stop,” Howard said. “However, cloth masks are protective for those around an infected wearer.” Some research, he added, shows “it is far better to use higher-quality masks, or alternatively add a mask fitter.”

The first large, randomized trial to test mask efficacy in a real-world setting recently was completed in Bangladesh, where nearly 350,000 people in rural parts of the country were tracked. The study has not completed the peer-review process, but the authors report that “when surgical masks were employed, 1 in 3 symptomatic infections were avoided for individuals 60+ years old, the age group that faces the highest risk of death following infection.”

The results for cloth masks were less conclusive. A separate study sent to us by Paul spokeswoman Kelsey Cooper — from 2015, before the coronavirus pandemic — found that cloth masks should not be recommended for health-care workers, particularly in high-risk situations, because “moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection.” The findings do not apply to surgical masks or high-quality masks.

The same researchers posted an update after the coronavirus pandemic began: “Health workers are asking us if they should wear no mask at all if cloth masks are the only option. Our research does not condone health workers working unprotected. We recommend that health workers should not work during the Covid-19 pandemic without respiratory protection as a matter of work health and safety. … If health workers choose to work using cloth masks, we suggest that they have at least two and cycle them, so that each one can be washed and dried after daily use.”

How does a mask stop coronavirus particles?

Imagine an infected person who is breathing, talking, singing, exercising, coughing or sneezing in a crowded room. Several studies have found that face masks are able to capture the airborne infectious particles that can spread the coronavirus. That’s what scientists refer to as “source control,” and that’s why public health authorities recommend masks in some indoor settings along with vaccinations, social distancing and other measures.

“There is laboratory-based evidence that household masks have filtration capacity in the relevant particle size range, as well as efficacy in blocking aerosols and droplets from the wearer,” the PNAS study says. “That is, these masks help people keep their emissions to themselves. A consideration is that face masks with valves do not capture respiratory particles as efficiently, bypassing the filtration mechanism, and therefore offer less source control.”

As the JAMA study says: “Exposure is greater the closer a person is to the source of exhalations. Larger droplets fall out of the air rapidly, but small droplets and the dried particles formed from them (i.e., droplet nuclei) can remain suspended in the air. In circumstances with poor ventilation, typically indoor enclosed spaces where an infected person is present for an extended period, the concentrations of these small droplets and particles can build sufficiently to transmit infection.”

This study found that community masking reduces coronavirus transmission rates in two ways — first, by blocking the virus-laden droplets being exhaled (source control) and second, by protecting uninfected wearers, although masks were found to be less effective for this group.

“Masks form a barrier to large respiratory droplets that could land on exposed mucous membranes of the eye, nose, and mouth,” the study says. “Masks can also partially filter out small droplets and particles from inhaled air. Multiple layers of fabric and fabrics with higher thread counts improve filtration. However, the observed effectiveness of cloth masks to protect the wearer is lower than their effectiveness for source control, and the filtration capacity of cloth masks can be highly dependent on design, fit, and materials used.”

‘1.8 million children … zero covid deaths’

Paul also brought up Sweden in this interview, arguing that the country, which had no mask requirement for schools, did not see worse coronavirus transmission or mortality rates. He said zero children had died of covid-19, but the official Swedish figures show that 14 people ages 0-19 had died of the disease as of the most recent update.

A study published in August in the Scandinavian Journal of Public Health found that Norway, a neighbor to Sweden that imposed stricter coronavirus lockdown measures, had lower mortality rates. “The Covid-19-associated mortality rates per 100,000 person-weeks during the first wave of the pandemic were 0.3 in Norway and 2.9 in Sweden,” it says.

“All-cause mortality in Norway was lower during the pandemic, whereas the all-cause mortality among elderly people in Sweden increased substantially,” the researchers found. “In previous years, both countries have seen a decreasing trend in all-cause mortality. It remains to be seen whether the observed excess deaths in Sweden during the pandemic may, in part, be explained by mortality displacement and whether the Covid-19 pandemic and mitigation measures are associated with other harms or benefits.”

Paul’s spokeswoman said he was referring to a letter published by a Swedish researcher in February in the New England Journal of Medicine. “Despite Sweden’s having kept schools and preschools open, we found a low incidence of severe Covid-19 among schoolchildren and children of preschool age during the SARS-CoV-2 pandemic,” it says, adding that from March to June 2020, “no child with Covid-19 died.”

That’s a few months, not the year or year and a half Paul mentioned. The letter, now outdated, was peer-reviewed by some academics and criticized by others, who said it ignored school outbreaks of Covid-19, among other issues.