Researchers stress need to mask noses, too
KANSAS CITY, Mo. — Wearing a mask without covering your nose is like applying your first round of sunscreen at the end of a day at the beach — pointless.
That’s because scientific research has found that the coronavirus infects your nose first, using it as an entry point to the rest of your body and as a mucousy hot spot for rapid replication.
So people who don’t cover their nose with their mask risk exposing their most infectious organ to others and increase their own chances of contracting COVID-19.
“If the nose is the dominant initial site from which lung infections are seeded, then the widespread use of masks to protect the nasal passages, as well as any therapeutic strategies that reduce the virus in the nose, such as nasal irrigation or antiviral nasal sprays, could be beneficial,” Dr. Richard Boucher, the co-senior author of a May study on the topic from the University of North Carolina at Chapel Hill, said in a news release.
The study’s researchers found that ACE2 — the protein the coronavirus uses to enter human cells — was more abundant in nasal passages than those down in the respiratory tract.
The results looked like a “striking” gradient from “high infectivity of SARSCoV-2” to “less infectivity” as researchers examined cells in the nose, throat and lungs.
When the virus becomes “firmly established” in the nose, the pathogen then makes its way to the lungs, where it can cause “more serious disease, including potentially fatal pneumonia,” the researchers said.
A separate study published in April in the journal Nature Medicine found the same results.
“This is the first time these particular cells in the nose have been associated with COVID-19. While there are many factors that contribute to virus transmissibility, our findings are consistent with the rapid infection rates of the virus seen so far,” Dr. Martijn Nawijn of University Medical Center Groningen in the Netherlands, who played a role in the study, said in a news release.
“The location of these cells on the surface of the inside of the nose makes them highly accessible to the virus, and also may assist with transmission to other people,” Nawijn said.
ACE2 was also found in the cells of the cornea and the lining of the intestine, according to the study, meaning another possible route of transmission is via the eye, with some potential for spread via fecal matter, the release said.
The Centers for Disease Control and Prevention says the correct way to wear a mask is to secure it over the nose and mouth and under the chin.
Some people have said wearing a mask and covering their nose makes it hard to breathe and could poison them with their own exhaled carbon dioxide. But experts, including many doctors who wear masks every day, have debunked that theory.
“Carbon dioxide molecules freely diffuse through the masks, allowing normal gas exchange while breathing.” Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital in New York, told Healthline.