A Lost Sense of Smell: All About the Strangest New Coronavirus Symptom

Loss of smell appears to be yet another symptom to watch for in people who otherwise are not extremely ill

Photo: Werayuth Tessrimuang/EyeEm/Getty Images

Some people diagnosed with Covid-19 have lost their sense of smell and even the ability to taste food according to a statement this week from ENT UK, a British group representing ear, nose, and throat surgeons. The possibility has not been formally studied, but anecdotal evidence from doctors in multiple countries suggests health care providers should look for the symptom as a possible indicator of the coronavirus infection.

Total loss of smell, called anosmia, can be caused by many viruses, including various strains of both coronaviruses and rhinoviruses, both of which can cause the common cold. Partial loss of smell is called hyposmia. Either can be accompanied by a loss of taste, called dysgeusia.

“There is already good evidence from South Korea, China, and Italy that significant numbers of patients with proven Covid-19 infection have developed anosmia/hyposmia,” wrote Dr. Claire Hopkins, an ENT surgeon and professor at King’s College London, and Dr. B. Nirmal Kumar, president of ENT UK. “In Germany, it is reported that more than two in three confirmed cases have anosmia. In South Korea, where testing has been more widespread, 30% of patients testing positive have had anosmia as their major presenting symptom in otherwise mild cases.”

Some of the people in Germany who had anosmia were not congested, Dr. Clemens Wendtner, a professor of medicine at the Academic Teaching Hospital of Ludwig-Maximilians University of Munich, told the New York Times.

Anosmia can be triggered by other diseases, too — anything that blocks, disrupts, or kills the olfactory nerve cells high up in the nasal cavity. It’s usually not serious by itself and typically subsides in weeks or months. However, the sense of smell gradually declines with age, too, like eyesight and other bodily functions.

Anosmia can also be caused by high blood pressure, poor nutrition, seasonal allergies, Alzheimer’s and other diseases, and some medications according to Johns Hopkins Medicine.