Why does COVID-19 Result in Loss of Smell?

Anosmia, or the loss of smell, can be signs of many conditions. For example, a cold, sinus infection, and even an early stage to Alzheimer’s and Parkinson’s ceases all can start with anosmia. In fact, the reduced ability to smell is quite common; around 12.4% of Americans over the age 40 have some hyposmia. 

However, during this time in life, anosmia is most likely associated with COVID-19. Anosmia may be a first or early symptom for some, or for others, it may be the only symptom of the virus. Although there is an urge to look at anosmia as diagnostic, because there are so many cases of COVID-19 in the world, one’s anosmia around this time is most likely to be linked to the virus, not anything else. 

Because of the loss of smell, scientists have been given more information on how COVID-19 works. In late February, chemosensory scientists, or those who study sensory nerve endings that mediate taste and smell, began discussing the connection between anosmia and COVID-19 reported on social media. They sent out a survey and collected over 30,000 responses which allowed the scientists to ask whether there is a significant decrease in smell, tase, or nasal sensation related to the virus. According to Scientific American, scientists conducted this survey to visualize “the sheer number of infected people [leading them] to notice the usual level of anosmia and to consider this (level of anosmia from COVID-19) as extraordinary.”

But from studies before, having anosmia from COVID-19 is seen in 30-98 percent of infected people in hospitals, which is much more than other respiratory infections. This study along with many others indicate that the virus is attacking the sense of smell in particular. Research on this matter is flowing out, and so how exactly does the virus attack the sense of smell? In short terms, the virus is attacking supporting cells which are the other cells surrounding the receptors and tissue in the nose, causing one to lose their sense of smell. 

Usually, anosmia is likely to be helped without doing anything. But one thing someone can do is smell training. Smell training is where a trainer gives you strong scents to smell, stimulating the nerves in an attempt to regain the sense of smell. 


Kay, Leslie. “Why COVID-19 Makes People Lose Their Sense of Smell.” Scientific American, Scientific American, 13 June 2020, 

HuffingtonPostUK. YouTube, YouTube, 18 May 2020,–k75lz7zgo. 

“Blog: Senseless Life, or A Year With No Sense of Smell or Taste.” Free Library of Philadelphia,

Categories: Clinical