- Researchers say COVID-19 face masks are helping people with outdoor allergies because they filter out pollen.
- But they say people need to keep their masks clean and remove them properly.
- On the other hand, people with indoor allergies, such as to pet hair and dust mites, may have more serious cases this year due to stay-at-home orders.
All data and statistics are based on publicly available data at the time of publication. Some information may be out of date.
COVID-19 preventive measures, such as mask wearing, may have additional benefits for people with pollen allergies.
However, for people who have issues with indoor allergens, COVID-19 lockdowns may be making things worse.
“A lot of our pollen-allergic patients are actually doing very well because they tend to stay indoors, and when they’re going outdoors they’re wearing a mask. They’re doing avoidance measures, so they’re doing better,” Dr. Rita Kachru, an allergy specialist at UCLA Health in California, told Healthline.
“What we’re finding is patients who have indoor allergies, such as dust mite, cat, or dog allergies, are actually doing worse,” she added.
In the United States, as many as
Reactions occur when the immune system incorrectly identifies allergens like pollen as a threat and mounts an immune response. This can cause sneezing, nasal congestion, a runny nose, and itchy eyes.
Pollen is airborne and can be inhaled. But allergy experts have noted since mask wearing became commonplace across the United States, many people have reported changes to their allergy symptoms related to pollen.
“There has been a decrease in symptom severity with mask use,” Dr. Sayantani Sindher, a professor of allergy and immunology at Stanford University School of Medicine in California, told Healthline.
The authors of the study report that both standard surgical masks and N95 respirators can filter out airborne allergens.
A standard surgical mask can filter particles larger than 3 micrometers, while an N95 mask can filter particles as small as 0.04 micrometers.
Pollen is typically between 10 and 100 micrometers in size. Fungal spores are usually between 2 and 50 micrometers, and house dust mite feces are between 10 and 40 micrometers.
Wearing a mask could filter out all these allergens.
“Masks that have filtration levels that can catch the small particles like pollen can help prevent against the inhalation of pollen. You just have to make sure that your mask is clean,” Dr. Elisabeth Ference, an ear, nose, and throat doctor at Keck Medicine of USC, told Healthline.
Ference said proper care of masks is important not only for avoiding COVID-19 transmission but also for avoiding allergens, especially for people with allergies.
“When people are reusing their masks without washing them, pollen can actually build up on the mask, and if you’re putting that mask on your face, then you can actually be putting more pollen on your face,” she said.
“If the outside of the mask picks up pollen and you touch the outside of the mask and then touch your eye or your nose, you could have an allergic reaction from the pollen that collects on the mask. That’s why it’s important we wash our masks frequently,” Ference said.
Proper mask handling and removal is also important to avoid viruses and other irritants.
“When we advise people of how to remove the mask, it is to remove it from the side so you’re not really touching the front part of the mask, and to limit touching it,” Kachru said.
“When you reuse it, be aware whatever particles fell on top of the mask — whether it’s a virus, whether it’s an allergen, whatever it is — you want to decrease your exposure, so you’re not flipping the mask, because then, yes, you will be exposed to it,” she added.
The CDC advises people, particularly those with allergies, to wash masks after each use.
Allergens don’t just exist outside.
The experts who spoke with Healthline said their patients with indoor allergies have seen an increase in symptoms during COVID-19 that’s related to stay-at-home measures.
“My patients who have allergies that are found inside the home, their allergies are much worse just because we are confined to our homes so much more during the course of our days,” Ference said.
“I’ve seen many people who previously didn’t spend that much time in a house with carpet, but now that they’re home a lot, they’ve actually had worsening of their nasal symptoms due to indoor allergens. It’s interesting trading one set of allergens for another,” she added.
Common indoor allergens include cockroaches, mold, cats and dogs, and dust mites.
“Dust mites are little mites that live everywhere. They live on our skin, they live on mattresses, they live on carpet, on clothes. They love anything they can absorb into,” Kachru said.
Keeping the home environment as allergy-friendly as possible, experts say, is the best way to avoid allergy symptoms during extended periods spent inside.
“Dust mites especially love upholstery, so pillows, curtains, carpet. Try to remove as much as possible extra upholstery, especially from places where you’re spending a lot of time, such as bedrooms,” Ference said.
“During the pandemic, I see a lot of my patients who both sleep in their bedrooms and it’s their quiet workspace as well, and if the bedroom is carpeted or they have extra curtains, that can be an area for dust mites to collect,” she said.
An 2020 study published in the summer described the combination of dust mites and COVID-19 lockdowns as the “perfect storm” for people who have indoor allergies.
Sindher said a good cleaning routine to combat some allergens found in the home is important.
“Cleaning and reducing dust mites, pet dander in the home can absolutely help symptoms from allergies, if those allergens are a trigger,” she said.
“My main suggestion is that sweeping can actually cause the tiny allergens to become suspended in the air and then resettle, so not really improving the issue. I typically recommend vacuuming and mopping to really reduce the allergen load. Also bedding should be washed weekly (or more frequently as needed) in hot water,” Sindher said.