Updated: Sep 5, 2021
Covid-19 typically produces flu-like symptoms such as cough and fatigue. But it can also cause loss of taste and smell.
How does the virus attack the sense of smell: The virus can cause loss of smell in two ways. One is that the virus causes an inflammatory reaction inside the nose that can lead to loss of olfaction or smell. This inflammation can also occur due to sinusitis, polyps in the nose and even allergies. It can act as a barrier for smell molecules to enter your nose, meaning you can’t physically pick up the smell. The other possibility is that the SARS-Cov-2, that causes Covid-19 binds to a protein called ACE-2, which is found abundantly in your nose and mouth. ACE-2 is not found on olfactory neurons, but it is found on cells that surround and support these nerve cells. Most covid patients lose their sense of smell by third or fourth day and regain it within two to three weeks. Losing your smell could affect your taste buds and also your appetite.
How do I know if my smell loss is related to Covid-19: With most viral infections, smell loss will occur after the other viral symptoms- the nasal congestion and runny nose. With Covid-19, smell loss is one of the first signs of infection. Smell loss is actually an early sign of Covid-19 and usually occurs for those who have a mild form of the virus. Patients with smell loss normally recover at home and are not admitted into the hospital or on a ventilator. Another major difference is the length of smell recovery. With other viruses, recovery could take months and sometimes even years. Smell recovery for Covid-19 patient usually takes about four weeks. This may be because Covid-19 affects supporting cells, which regenerate faster than olfactory sensory neurons.