A sudden loss or reduced sense of smell or taste could indicate COVID-19 before other symptoms appear, according to the American Academy of Otolaryngology.
The Academy recently proposed adding these symptoms to the list of screening tools for possible COVID-19 infection. It recommends that people with these symptoms—even without other respiratory diseases like allergies or a cold—should alert their doctor and seriously consider self-quarantine and testing.
“Since these people do not show other symptoms, they won’t know to self-quarantine, which could spread the virus,” says Rachel Kaye, an assistant professor of otolaryngology at Rutgers New Jersey Medical School, who is beginning to track these occurrences in the United States.
Here, Kaye explains the connection between these senses and COVID-19:
Why might loss of smell or taste be an early symptom of coronavirus?
Viruses are a common cause of changes to the sense of smell or taste that can occur with an upper respiratory infection. A viral infection can result in both inflammation and swelling of the nasal cavity lining, leading to nasal congestion, which in turn causes a change in smell. Secondly, there is some evidence that viral infection can lead to neurologic damage of smell receptors and neurons.
Can something other than coronavirus cause the loss of these senses?
Yes, certainly. If you have an upper respiratory infection with nasal congestion, the decreased nasal airflow can change smell sensation significantly. Also, many bacterial and viral infections, notably upper respiratory infections, can cause changes to one’s sense of smell.
There are other causes for change of smell, including sinus disease, side effects of medication, smoking, neurologic disorders, trauma, and normal aging, to name a few.
What should people do if they experience this symptom?
We advise patients to speak with their primary care doctor or their otorhinolaryngologist about their specific symptoms and potential COVID-19 exposure. If there is a known COVID-19 exposure, then the person may want to self-isolate until a definitive diagnosis is obtained.
That being said, although the anecdotal evidence is increasing, there have not yet been any scientific studies published regarding this and so strict protocols for people experiencing these symptoms are lacking.
Source: Rutgers University