News: Nasal nerve damage linked to COVID loss of smell, new study says

The effects of COVID-19 can include a prolonged and damaging inflammatory assault on nerve cells in the nose, a new study published by Science Translational Medicine shows. These cells are responsible for the sense of smell and examining them has revealed why some people recover their loss of smell after recovering from COVID-19, while others do not. For some, the body’s immune response becomes dysregulated and stays this way even when the virus can no longer be detected by laboratory tests, Medscape Medical News reported.

Using samples from 24 individuals made up three groups—people with post-COVID prolonged sense of smell, people with a normal sense of smell after recovery, and people who have never had COVID—the small study found that past the cells appeared to reflect a response to ongoing inflammatory signaling and these altered immune cell populations in olfactory epithelia contribute to long-term smell loss after COVID-19.

“The findings are striking,” said Bradley Goldstein, MD, PhD, an associate professor at Duke University School of Medicine in North Carolina, one of the study’s researchers, in a news release. “It's almost resembling a sort of autoimmune-like process in the nose.”

In good news, the study found that even patients most affected by the virus appeared to maintain the cell types that would be necessary for repairing their sense of smell. Its findings point scientists towards treatments that could at least partially help in this restoration, Goldstein said.

Editor’s note: To read Medscape Medical News’ coverage of this topic, click here. To read the full study, click here.