Should vaccinated Floridians be masking up again, and when? Health experts explain.

It’s been more than a year since the Centers for Disease Control and Prevention first advised Americans wear a mask to help prevent the spread of COVID-19.

And last week, the CDC asked everyone to mask up again. The new public health recommendations for mask protocol, which walk back some of the previous guidance, are: mask up indoors, regardless of vaccination status, in all areas where infection rates are high. Florida reported 21,683 new cases of COVID-19 on Saturday, the state’s highest one-day total since the start of the pandemic, according to federal health data.

But what kind of masks should we be wearing? Are they easier to find these days? And with more than a year of the pandemic behind us, have we learned anything new about mask-wearing?

For starters, we’ve learned that masks are not just for people with symptoms, said Dr. Cindy Prins, associate professor of epidemiology at the University of Florida. With the current COVID-19 surge in the state, she recommends all people mask up indoors, even if they’re vaccinated. In crowded outdoor settings, throwing a mask on would also be a smart decision, Dr. Prins said, though data specific to how the delta variant spreads outdoors is not available.

Dr. John Glenn Morris Jr., professor and director of UF’s Emerging Pathogens Institute, said there is a lot to be learned about the delta variant, but mask-wearing when done properly still helps prevent transmitting the virus.

“It makes sense for people who have been vaccinated to put on masks again,” Dr. Morris said. “Not so much to protect themselves, but to protect the people around them.” This includes children under 12, who cannot be vaccinated, and immunocompromised people. Data from the CDC following their recent announcement suggests vaccinated people who become infected with the delta variant may have higher viral loads of the virus than with other variants, making it more likely for them to transmit the virus to other people.

Dr. Morris recommends wearing a mask in a high-risk setting — times when you are in a closed space, have a lack of social distancing or find yourself somewhere with poor ventilation — and to use a mask that follows the CDC guide for a proper mask and face covering fit. Those guidelines include making sure your mask has two or more layers of washable, breathable fabric, and a nose wire to prevent air from leaking out of the top of the mask.

Dr. Prins also emphasized the importance of wearing a mask that fits properly, and suggests double-masking when necessary — essentially, wearing a surgical mask and then a cloth face covering over that.

N95 masks continue to be the most effective mask you can wear, and they offer protection when it comes to an individual person transmitting COVID-19 and also getting it from someone else. But, experts said, wearing one is not worth it if it compromises the fit. That goes for all kinds of masks.

“You need to wear a mask that you’re going to be able to tolerate wearing,” Dr. Prins said. “It doesn’t do any good if you’re wearing a mask but you find it uncomfortable and you’re pulling it below your nose.”

N95 masks filter the air you are inhaling better than any other face covering. They are 99 percent effective at blocking particles above 10 microns and below one micron, and roughly 95 percent effective for every particle size in between, said Dr. Thomas Unnasch, the lead for global and planetary health at the college of public health at the University of South Florida.

The COVID-19 virus particle is less than 0.5 microns, but that is not the actual size of them in the air. The viral particles travel in carriers, like beads of spit or aerosol, creating a phenomenon that Dr. Unnasch compared to a bus with passengers inside trying to fit under a highway bridge that is lower than the height of the vehicle. If the bus (carrier) can’t fit, the passengers (virus) won’t go through.

“As long as the mask can catch the bus, it catches the virus part,” Dr. Unnasch said.

Surgical masks and double-layered cloth masks are the next most protective, Dr. Unnasch said, followed by single cloth masks, which could be almost half as effective as an N95 at blocking the virus. His advice is to opt for a mask that’s “readily available.” He suggested getting three “fairly heavy weaved double-layered cloth” masks and to regularly wear them in indoor settings with other people around.

Dr. Morris warned of people flocking to buy N95 masks, because medical workers and high-risk people still need those most, and backsliding into an N95 supply shortage would be a problem. But in general, all kinds of masks are easier to find now than they were a year ago.

In stark contrast to the early days of the pandemic, it’s almost difficult to find a store that doesn’t sell masks in some capacity. Big box retailers offer a number of options, and online stores like Etsy and Amazon sell cloth masks in a variety of designs. Surgical masks are available in bulk at many places that sell cloth masks, and as of this week, N95 and KN95 (a Chinese version that is made to a similar standard) mask packs were readily available on Amazon.

“Not only have they become more available but I would say that they’ve really become part of our wardrobe. You see people make lots of fashion statements with their masks,” Dr. Prins said. She likes the festive masks, as long as style isn’t compromising fit and the mask has multiple layers.

The three experts we talked to agreed that masks of any kind offer some protection, whether to the wearer or to the community.

“For most people, we still see a substantial degree of protection with a regular mask,” Dr. Morris said.

And beyond mask-wearing, the experts encouraged vaccinations as the ultimate tool in stopping the spread of the virus.

“Get vaccinated now. Capital N-O-W. Now,” Dr. Prins said.

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