Can Face Masks for COVID-19 Also Protect You from the Flu?
Here's how to keep yourself (and others) safe from influenza and COVID-19 this flu season.
For months, medical experts have warned that this fall will be a doozy health-wise. And now, it's here. COVID-19 is still widely circulating at the same time that cold and flu season is just beginning.
It's only natural to have a couple — OK, a lot — of questions about what you can do to protect yourself, including whether the same face mask that you wear to stop the spread of COVID-19 can also protect against the flu. Here's what you need to know.
Fact: The official recommendations for preventing the spread of the flu don't include wearing masks.
The Centers for Disease Control and Prevention doesn't currently recommend that people wear a face mask to prevent the spread of the flu. What the CDC does recommend is the following:
- Avoid close contact with people who are sick.
- Wash your hands with soap and water.
- When soap and water aren't available, clean your hands with an alcohol-based hand sanitizer.
- Try to avoid touching your eyes, nose, and mouth as much as possible.
The CDC also stresses the importance of your flu shot, noting that "getting a flu vaccine during 2020-2021 will be more important than ever." While the vaccine doesn't protect against or prevent the spread of COVID-19, it can reduce the burden of flu illnesses on the health care system and lower the risk you'll contract the flu and COVID-19 at the same time, says John Sellick, D.O., an infectious disease expert and professor of medicine at the University at Buffalo/SUNY. (More here: Can the Flu Shot Protect You from Coronavirus?)
Regardless, public health experts strongly recommend wearing a face mask during this year's flu season.
While the CDC doesn't recommend wearing a mask to prevent the spread of the flu, specifically, experts say it's really not a bad idea — especially since you should be wearing one to stop COVID-19 as well.
"The same methods for preventing the spread of COVID-19 work for the flu, too. That includes wearing a mask," says William Schaffner, M.D., an infectious disease specialist and professor at the Vanderbilt University School of Medicine. "The only difference is that you can get vaccinated against influenza." (Related: After Beating COVID-19, Rita Wilson Is Urging You to Get Your Flu Shot)
"Masks are an added protection, on top of being vaccinated, and we should all be wearing them now anyway," adds infectious disease expert Aline M. Holmes, D.N.P., R.N., a clinical associate professor at Rutgers University School of Nursing.
In fact, wearing a mask to prevent the spread of the flu has actually been studied in pre-COVID times. One systematic review of 17 studies published in the journal Influenza and Other Respiratory Viruses found that mask use alone wasn't enough to prevent the spread of the flu. However, the use of surgical masks was successful when paired with other flu prevention methods, such as good hand hygiene. "Mask use is best undertaken as part of a package of personal protection, especially including hand hygiene in both home and health care settings," the authors wrote, adding that, "early initiation and correct and consistent wearing of masks/respirators may improve their effectiveness."
Another study published in the medical journal PLOS Pathogens followed 89 people, including 33 who'd tested positive for the flu at the time of the research, and had them exhale breath samples with and without a surgical mask. The researchers discovered that 78 percent of volunteers exhaled particles that carried the flu when they were wearing a face mask, compared to 95 percent when they didn't wear a mask — not a huge difference, but it's something. The study authors concluded that face masks are "potentially" an effective way to limit the spread of the flu. But, again, masks seem to be most effective when combined with other hygiene and prevention practices. (Related: Can Mouthwash Kill the Coronavirus?)
A newer study, published in August in the journal Extreme Mechanics Letters, found that most fabrics (including new and used garments made of cloth, cotton, polyester, silk, etc.) block at least 70 percent of respiratory droplets. However, a mask made of two layers of T-shirt cloth blocked droplets more than 94 percent of the time, putting it on par with the effectiveness of surgical masks, the study found. "Overall, our study suggests that cloth face coverings, especially with multiple layers, may help reduce droplet transmission of respiratory infections," including the flu and COVID-19, the researchers wrote.
What kind of face mask is best for preventing the flu?
The same rules apply for a face mask to protect you from the flu as the ones that can stop the spread of COVID-19, says Dr. Sellick. Technically, an N95 respirator, which blocks at least 95 percent of fine particles, is ideal, but experts say those are hard to find and should be reserved for medical personnel.
A KN95, which is China's certified version of the N95, may also help, but it can be tricky to find a good one. "A lot of KN95s on the market are bogus or counterfeit," Dr. Sellick says. Some KN95 masks have been granted an emergency use authorization by the Food and Drug Administration, "but that doesn't guarantee that every single one is going to be good," he explains.
A cloth face mask should do the job, though, he adds. "It just has to do be done the right way," he notes. He recommends wearing a mask with at least three layers, per recommendations from the World Health Organization. "Nothing is going to be as good as medical masks, but a cloth face mask is definitely better than nothing," says Dr. Sellick.
The WHO specifically recommends avoiding materials that are super stretchy (since they can't filter out particles as effectively as other, more rigid fabrics), as well as masks made of gauze or silk. And don't forget: Your face mask should always fit tightly across your nose and mouth, adds Dr. Sellick. (Related: How to Find the Best Face Mask for Workouts)
Bottom line: To protect yourself against the flu, Dr. Sellick recommends that you keep doing what you've been doing to prevent the spread of COVID-19. "We used our flu message for the coronavirus and now we're using it for flu," he says.
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.