Why is this lost sense of smell occurring as a result of COVID-19?
No one knows for sure at this point. The question is: Is it direct damage to the olfactory nerve, which transmits information relating to smell to the brain, or is it due to damage to the part of the brain that controls the sense of smell? Either way, it is nerve damage.
Does this symptom occur with other coronaviruses?
No. That’s the strange part about this. This is a unique feature of COVID-19. To my knowledge, losing one’s sense of smell is not associated with any other infectious diseases.
How is the loss of smell linked to a loss of taste?
We tend to think of the sense of taste as residing in the mouth, chiefly the tongue. But in fact, the sense of taste also depends a great deal upon the sense of smell. If you lose your sense of smell, you also lose the sense of taste. When you lose your sense of taste and smell, it can have a huge impact on a person’s quality of life. It’s very hard if you can’t enjoy your food, and it could lead to people losing weight and energy as a result.
How severe is this loss of smell and taste?
It varies greatly. Some people say it’s very mild and it’s better in a week or so. Other people lose it completely — they just have no sense of smell, and it can take months until it gets better. Unfortunately, there’s no predicting who’s going to get it, what the course will be, or how long the recovery will be.
Will people regain their sense of smell?
As the study indicated, it can go on for months, but the good news is that it seems that most people recover all or almost all of it. This disease is new, so nobody knows what it’s like five years down the line or even two years down the line. But I can tell you that most people eventually seem to get most of it back.
Why does it take so long?
The most important thing to know about nerve damage is that the recovery is typically slow. Once the nerve has been damaged, the healing process takes a long time. For instance, if somebody has Bell’s palsy, a nerve condition in which half of the face becomes paralyzed, the recovery can take months. So this is fairly typical of what we see with nerve damage or any kind of neurologic damage. It’s a slow, somewhat unpredictable recovery.