You've likely seen surgical masks flying off the shelves — here's why.
new masking recommendations
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It can feel downright dizzying trying to keep up with public health guidelines related to the ongoing COVID-19 pandemic, particularly as cases continue to surge nationwide.

At this point, wearing masks in public is a non-negotiable to help protect yourself and those around you from catching the virus (not to mention other germs, such as the flu), but you might want to reconsider donning that cute cloth mask that matches your outfit.

As newer strains of the virus spread more quickly, Rochelle P. Walensky, M.D., M.P.H., director of the U.S. Centers for Disease Control and Prevention, tweeted that the agency is preparing to update their mask recommendations this week. The goal? To help the public be better aware of the options available to them and to, hopefully, help reduce community spread as much as possible. (Read more: Why Are the New COVID-19 Strains Spreading More Quickly?)

And while Dr. Walensky emphasized the fact that any mask is better than no mask, the highly transmissible (read: more contagious) COVID-19 variants currently circulating (Delta and Omicron) means that the type of mask you choose really does matter. The current CDC mask guidance — which was last updated in October 2021, but has remained roughly the same since the beginning of the pandemic — recommends wearing a well-fitting mask made of at least two layers that snugly covers your nose and mouth and reserving N95 respirators for health care workers. However, the new guidance is expected to feature some important changes.

How do masks protect against COVID-19?

Even though they're a ubiquitous part of everyday life these days, it's worth a quick refresher about how masks work and why certain ones are more effective than others. Viruses such as COVID-19 spread via airborne particles and droplets, which means infected patients can release those little bits of respiratory fluids that contain SARS CoV-2 (the virus that causes COVID-19) into the air by breathing, as well as when they're speaking, singing, exercising, coughing, and sneezing, according to the U.S. Environmental Protection Agency. (In case you forgot, here's how COVID-19 transmission happens.)

These virus-carrying droplets or aerosol particles range in size from visible to microscopic. And while cloth masks can help stop larger molecules, certain masks are more effective at filtering smaller aerosols or particles, such as the ones found to contain SARS CoV-2.

Which masks are best for protecting against COVID?

The reason the CDC is rethinking its guidelines is because new data is emerging on the effectiveness of different types of masks. For example, a large, real-world study done in villages around Bangladesh published in December 2021 found that surgical masks (the flat, rectangular ones that are typically light blue in color) offer more protection than cloth masks. More specifically, in communities where people wore surgical masks, there were 11 percent fewer cases of COVID than in those where people weren't wearing masks at all. In villages where people wore cloth masks, COVID infections were reduced by only 5 percent. (As a result, the Mayo Clinic has changed their mask requirements so all patients and visitors must be wearing a medical mask — i.e. surgical, N95, or KN95 — and some international airlines, for example, have started banning cloth masks onboard.)

So, of course, not wearing a mask offers the least amount of protection against COVID; cloth masks come next, offering at least a little protection, especially if they're well-fitting and have at least two layers; surgical/medical masks offer significantly more than that. Even more protective than surgical masks are respirators, which are the gold standard when it comes to fighting off virus-carrying droplets or aerosols. In the U.S., the most commonly available respirators are called N95s and KN95s; in Europe, they're called FFP2s. These are the most well-fitting, keep the tightest seal around your nose and mouth, and are designed to keep out the vast majority of droplets and aerosols, no matter their size. (ICYDK, the "95" in the name means that the respirator has been approved to filter out at least 95 percent of potential illness-causing particles.)

The biggest difference between KN95s and N95s is that N95s are made in the U.S. and KN95s are manufactured in China. The latter are subject to a fit test on actual humans to ensure there's little to no leakage, while N95s are not — though they are required to meet standards set by the National Institute for Occupational Safety and Health (NIOSH), such as filter efficiency. (Read more: Can an N95 Mask Actually Protect You from the Coronavirus?)

Unfortunately, just as there are plenty of fake COVID test kits on the block these days, you'll also find many counterfeit masks or ones subject to price gouging from greedy sellers. In fact, about 60 percent of KN95 respirators in the U.S. are fake and do not meet NIOSH requirements, according to the CDC. (To help avoid buying a counterfeit, the CDC offers resources via a webpage and webinar to help you purchase a legit respirator.) For NIOSH-approved masks and respirators, check out ProjectN95, a national nonprofit organization working to provide low-cost and effective personal protective equipment (PPE) to anyone who needs it.

If you're panicking because these prized N95 and KN95 masks are hard to find, rest assured: Even though cloth masks aren't the most protective option, it doesn't mean the ones you have are now useless. You can absolutely still wear your cloth mask over a medical mask — in fact, wearing both (i.e. layering two masks) can reduce the chances of virus particles evading by more than 90 percent, according to the CDC.

The information in this story is accurate as of press time. As updates about coronavirus COVID-19 continue to evolve, it's possible that some information and recommendations in this story have changed since initial publication. We encourage you to check in regularly with resources such as the CDC, the WHO, and your local public health department for the most up-to-date data and recommendations.