February 01, 2021
Researchers are investigating the effects of COVID-19 on our senses, including how long any effect lasts, as well as treatment. Here are some frequently asked questions relating to the impact of COVID-19 on our sensory system:
Q. How many people lose their sense of smell?
A. The exact proportion varies, ranging from 18% to 41%.
Q. Why are people with COVID-19 losing their sense of smell?
A. Although the mechanisms are not fully understood, there is an emerging consensus that smell loss occurs when the coronavirus infects cells that sustain neurons in the nose. There may be other reasons, however, that COVID-19 causes loss of smell. For example, a research team in Italy found that odor and taste loss occur at the same time as blood levels increase due to an inflammation-signalling molecule called interleukin-6; and a post-mortem study published last December showed clear signs of inflammation, such as leaky blood vessels, in the olfactory bulbs of individuals who had had COVID-19.
Q. How soon will the damaged senses come back?
A. Most people will recover their odor and taste senses within weeks. For others, however, the effects are more intense. People whose senses do not return immediately may recover them slowly. This may be due to the olfactory sensory neurons being re-wired as they regenerate.
Q. How does the loss of a person's chemical senses permanently affect them?
A. One effect is that it makes people more vulnerable to dangers like fire and food poisoning.
Q. Are there treatments available for restoring these senses?
A. So-called scent therapy, in which people regularly sniff administered odors to relearn them, is one option currently being investigated.
More details:
Nature 589, 342-343 (2021)
DOI: https://doi.org/10.1038/d41586-021-00055-6
Luciana Aparecida Campos Baltatu, Ph.D.
College of Health Sciences
Abu Dhabi University
