Do masks prevent omicron? Here’s what we know about COVID infection


In my work covering COVID-19, I’ve interviewed hundreds of doctors, infectious disease experts and epidemiologists from institutions like the CDC, Harvard, Stanford, Yale, Johns Hopkins and the FDA’s Center for Biologics Evaluation and Research.

The subject of masks has arisen time and again, and while multiple doctors have acknowledged the missteps and bungled messaging regarding face masks, particularly during the early stages of the pandemic, those I’ve interviewed agree that masks remain a vital layer of protection in the fight against COVID-19. 

Of course, some guidance regarding preventative measures has changed over time as studies have given added insight into what works and what doesn’t. But some preventive measures have remained surprisingly consistent. Washing hands, steering clear of sick people, and eating healthy and exercising are all effective ways to stave off some illnesses and represent preventive health measures that predate the pandemic.  Similarly, surgical face masks have been used in hospitals for decades and by the public at large, long before COVID-19. It’s only in the age of social media misinformation and political polarization that masks have become so controversial. But setting politics aside, data on masks remains compelling with the preponderance of evidence supporting their efficacy in reducing transmission of airborne viruses like COVID-19.

Based on extensive interviews and research, below are answers to common questions about when and why masks make sense and the mechanics of how they protect against COVID-19.

How effective are masks, really? 

While face masks aren’t airtight (thank heavens!) and therefore cannot keep out every respiratory droplet that may contain disease and bacteria, they are effective at containing a high number of them. 

Various studies report different degrees of protection depending on how they were conducted and how data was collected, but a recent meta-analysis of multiple global studies found that masks are linked to a commanding 53% decrease in COVID-19 transmission when worn properly. An Arizona epidemiologist recently told me how N95 masks or surgical masks have proven to be especially effective. “Several studies have found that surgical masks are between 66% and 70% effective,” she said. 

Anyone doubting whether masks work need only look at how airborne diseases decrease in areas with high mask compliance. For instance, Primary Children’s Hospital in Utah ”typically deals with 80 to 120 RSV hospitalizations and dozens of intensive care unit stays per week on top of hundreds of yearly influenza hospitalizations,” as one article noted; however, in the winter of 2020/2021, when most Utahns were still wearing masks while shopping and at work, church, and school, the Salt Lake City hospital reported virtually zero flu or RSV hospitalizations. In fact, airborne illnesses were at an all-time low across hospitals throughout the state at the time.

More recently, one study found that communities with mask mandates had lower hospitalization rates than areas where masks weren’t required.

And even though masks are nowhere near 100% effective, experts consider some protection better than none. One pediatrician shared the following analogy last year: “You can’t tell me that every anti-masker we know wouldn’t change their tune about masks not providing ‘perfect protection’ if we showed the fallacy of that logic when applied to other things.”

He then suggested one considers the act of running across a field with people on both sides trying to pummel them with paintballs as they ran. “In that situation wouldn’t you rather have a shield in your hand that covered only part of your body, or would you honestly prefer no protection at all?” He then discussed how additional layers of protection such as a helmet or body armor could cause one to become even better protected to demonstrate how upgrading one’s mask can similarly provide increased levels of protection. 

Are some masks better than others? 

If increasing one’s level of protection against airborne viruses is the goal, then by now we all know that some masks are superior to others. Cloth masks are certainly better than no mask, but upgrading makes sense when better options are readily available. Surgical masks, for instance, are made up of more layers of protection than cloth masks. Researchers at Stanford and Yale contributed to a study last year that found that surgical masks are 95% effective at filtering out COVID-19 virus particles, compared to just 37% for cloth masks.

Unlike cloth masks, surgical masks are made from a non-woven plastic material called polypropylene that holds an electrostatic charge intended to contain air droplets that prevent the wearer from inhaling them. N95 and KN95 masks have the same electrostatic advantage, but they’re made up of even more layers of protection and have the advantage of also fitting more snugly to one’s face. 

Cloth and surgical masks tend to fit loosely, leaving gaps around the cheeks and nose which has been shown to make a big difference. A CDC study showed how a surgical mask could reduce risk of exposure to the wearer by nearly 65% by double-knotting the loops and tucking in the sides of the mask to close gaps. The CDC has excellent guidelines to help you make sure your mask fits properly. 

Upgrading one’s mask is especially important in the face of omicron. Early research suggests that omicron multiplies 70 times faster in the bronchial tract than previous iterations of the virus, and multiple early studies suggest that omicron may be able to render certain masks less effective by being able to infect individuals with a smaller viral load, a suggestion echoed by immunologist Wilfredo Garcia-Beltran. 

How do face masks work? 

Put simply, masks help prevent the transmission of airborne viruses by providing a barrier that traps or contains diseases and bacteria that commonly spread through small respiratory droplets. Airborne viruses include influenza (flu), whooping cough, tuberculosis, measles and respiratory syncytial virus.

Such droplets are expelled when someone with an airborne illness coughs, sneezes, shouts, laughs, talks or exhales in some other way. Each droplet (or floating air particle) becomes an infectious vehicle that can linger in the air, travel along air currents and adhere to surfaces, where they eventually may be inhaled by someone else.

COVID-19 is also known to be spread through airborne transmission, “so anything that gets in the way of the virus distributing through the air in high-enough concentrations to get nearby people sick is going to be key in preventing spread,” a Colorado-based epidemiologist recently told me. 

Why does it make sense to wear masks sometimes and not others?

Early in the pandemic, a Harvard epidemiologist had some helpful advice on this front: he told me to “think of where we are now like a budget,” and suggested that if people want to avoid closures of schools and churches (or more recently, canceled flights) it “means allowing a certain amount of transmission and deciding where you’re going to allow that transmission to take place and where you cannot.” 

Judiciously budgeting one’s face mask use in crowded indoor settings may help prevent the spread of viruses in those places while allowing children or individuals with special needs to remain mask free in other settings. In other words, just because masks work doesn’t mean we have to wear them every minute of every day. We can “budget” our face mask use in settings where masks make more sense. Going back to the aforementioned paintball analogy, there’s no sense in donning a shield, helmet and body armor if no one is firing any paint balls.

OK, so when and where does it make sense to mask up? 

The one piece of information that changed in 2021 regarding face masks was relaxed guidance about masking up outdoors. “Masks may not be necessary when you and the person you are caring for are outside and away from others,” the CDC now recommends. Crowded sporting events and concerts are still the exception where higher risk individuals (and those nearby) should still consider wearing them. 

But experts remain unified in recommending mask use when using public transit and in indoor settings where social distancing isn’t practical and airflow may be stagnant. Most experts also recommend masking up in small groups indoors unless everyone present is known to be vaccinated and boosted. 

One should also exercise more caution if you live in an area that’s experiencing a surge of new cases. NPR has a handy tool to check transmission levels near you.

What if I’m the only one wearing a mask? 

Masks work best when the majority of people in a room are wearing one because when an infected person wears a mask, a large percentage of their exhaled infectious particles are captured in the material immediately in front of their mouth and nose, which stops viral spread at the source. 

But evidence suggests that masks protect the wearer even when others remain mask free. The degree of protection depends on the quality of one’s mask, how well a space is ventilated, and the length of time someone is exposed to an infected person. One study showed an individual wearer to be protected by 17% to 27% in a cloth mask, 47% to 50% in a surgical mask, and 79% to 90% in a well fitted N95 mask regardless of whether others were wearing a face covering. 

Another study showed how when an infected person occupied the same space as an uninfected person where neither party wore a face covering, the uninfected person became infected within just 15 minutes. But the amount of time to become infected increased to 20 minutes when the uninfected person wore a cloth mask, to 30 minutes when wearing a surgical mask, and to 2.5 hours when wearing an N95 mask — even if the uninfected person was the only one wearing a mask. (It’s worth noting that the 2.5-hour time to become infected increases to a whopping 25 hours when both the uninfected person and the infected person wore an N95 mask.)

Should my child wear a face covering (in the classroom and beyond)? 

While it’s logical to conclude that masks benefit every able-bodied wearer regardless of age, the aforementioned “budgeting” analogy demonstrates why it may make more sense for adults to bear the burden of masking more than young children. After all, children often have lower levels of tolerance and depend especially on facial expressions and other nonverbal forms of communication as part of their development and while learning in various settings. Some experts have also expressed concern that young children in particular may begin mouth breathing if they wear a face covering too often, the detriments thereof having been well-documented.

What’s more, the CDC published a study last May that casted doubt on whether requiring children to wear a face covering in the classroom has a statistically significant benefit. As David Zweig wrote in The Atlantic last month, “the precise extent of (mask) protection, particularly in schools, remains unknown—and it might be very small.” As such, masking young children in the classroom is a more complicated question. Indeed, the World Health Organization specifically advises against masking children 5 and under.

That said, WHO does recommend children 12 and up to wear face coverings under the same circumstances as adults, and the CDC and the American Academy of Pediatric guidelines still encourage that “anyone over the age of 2, regardless of vaccination status, wear a well-fitting face mask when in public” — at least through the 2021-22 school year.

If masks are so effective, why did Dr. Fauci say they didn’t work early in the pandemic? 

Nearly two years into the pandemic, the most common argument against masks is that Dr. Anthony Fauci once said they weren’t effective. While it’s true that he appeared on “60 Minutes” early in the pandemic and said that masks don’t provide “the perfect protection that people think (they do),” and that the U.S. Surgeon General at the time tweeted something similar, Fauci has since explained that he and other public health officials were actually just “concerned that it was at a time when personal protective equipment, including the N95 masks and the surgical masks, were in very short supply.” Indeed, by early April 2020, the Strategic National Stockpile had been depleted, a potentially devastating situation for front-line medical workers. 

While one could certainly fault Fauci and other officials for not leveling with the American people, it’s worth noting that their actions at the time still demonstrated how important they considered masks to be. A physician last year told me, ”nothing convinced me more that I needed to get my hands on some masks for my family then when I saw how panicked Dr. Fauci was when he thought there weren’t enough masks to go around for doctors and nurses early in the pandemic.” 

I thought masks were supposed to be temporary? 

While “pandemic fatigue” is understandable and masks are absolutely both inconvenient and uncomfortable, COVID-19 is far from over. Indeed, America reported 4 million new cases last week alone — a caseload it took the country a full 6 months to amass in 2020. States across the country are shattering previous records — Utah reported more than 10,000 new cases on Wednesday.  

Omicron may be less deadly than earlier strains, but it is also more contagious. Former CDC director Dr. Tom Frieden recently posted to Twitter that in his 30 years of studying infectious disease outbreaks, “I’ve NEVER seen anything like the speed of Omicron.” The variant is tearing through some communities with such ferocity that the National Guard has been deployed to assist in several overcrowded hospitals. 

In other words, though most of us want to be done with this virus, it isn’t done with us, and Americans still need to do what we can to prevent its spread. 

Thankfully, most experts believe there’s light at the end of the tunnel as more and more of the country becomes vaccinated (or infected) and new treatment options become available. It’s as CDC director Rochelle Walensky told ABC News last month, ”masks are for now, not forever.”

Daryl Austin is a journalist based in Utah. His work has appeared in National Geographic, The Atlantic, The Wall Street Journal, Psychology Today and The New York Times.





Source link

We will be happy to hear your thoughts

Leave a reply

Ozinize
Logo
Shopping cart