COVID and loss of sense of smell (anosmia): who’s likely to get it and how long does it last?
Written by:As the coronavirus COVID-19 pandemic continues, symptoms such as a loss of smell (anosmia) and loss of taste are coming to the forefront. Originally, the main focus concerning symptoms was on coughing and fever, but a loss of senses has proven to hold a significant part in detecting who has the virus.
Learn from Professor Carl Philpott, a leading UK ENT surgeon, about COVID-related anosmia, who’s most likely to be affected and how long it lasts.
What’s the evidence that COVID-19 can lead to anosmia?
The WHO (World Health Organization), along with several countries, has added a loss of sense of smell (anosmia), to their official COVID-19 symptoms list. Global data is showing that around 60 per cent of infected patients experience it. In some data I’ve seen, a loss of sense of smell is even more common than the most well-known symptoms of fever and cough.
Can people lose their sense of taste too?
Yes, it is possible. Information based on COVID patients is suggesting that the virus could be affecting our senses by affecting the brain, potentially the central structures. If this is the case, it’s possible that both taste and smell are affected.
The Global Consortium for Chemosensory Research (GCCR), which I’m a part of, has gathered over 40,000 responses internationally concerning COVID’s impact on smell and taste. This data is suggesting that taste is being affected just as much as smell.
Does it happen gradually?
Anosmia from COVID-19 can appear suddenly. Someone may be fine in the morning but notice later on the same day that their sense of smell has gone. This is different from typical viral smell loss, which is usually much more gradual.
Is this symptom an early warning sign?
According to the GCCR data, about 20 per cent of people with COVID are experiencing a loss of smell before any other symptoms. Research is showing that about 20 per cent of patients with anosmia won’t have any other symptoms at all! Despite this, a larger amount of people with anosmia from COVID will experience its other symptoms.
The worrying aspect of anosmia being the only COVID symptom in some people is that this creates a higher risk that the virus will spread to others. Without the more noticeable symptoms e.g. cough and fever, many people, including health workers, won’t realise they have the virus and will risk passing it on to others.
Will the senses return?
So far, we’ve seen that 85 to 90 per cent of people with a loss of sense of smell get it back within two weeks.
Who is more likely to experience anosmia from COVID?
As much as 80 to 90 per cent of people with smell loss from COVID are women. It appears to be affecting younger people more often – the average age (compared to usual viral smell loss) is lower by a decade or so.
|
Usual viral smell loss |
COVID-19 smell loss |
|
Twice as many women report it than men |
Over 70 per cent of those reporting it are women |
|
Average age is 40 to 70 years old |
Average age is 30 to 40 years old |
|
Usually noticeable as other symptoms have become less intense |
Can be the only symptom and can appear suddenly |
|
Gradually returns; in those reporting persistence beyond a month 1 in 3 may recover over 3 years |
Usually returns to normal (suddenly) within 2 to 3 weeks in 85 to 90 per cent of cases; recovery in the remainder as yet unknown |
|
True taste not usually affected |
Bitter and sweet taste may also be reduced |
Should we self-isolate if we lose our sense of smell and taste?
I believe that those with a sudden loss of taste and smell should be encouraged to self-isolate, even if there are no other symptoms at all.
This is because other symptoms of COVID could develop later, or a person may be infected and only have a loss of smell – they can still pass the virus on to others.
You can still receive Professor Philpott’s leading ENT services throughout the pandemic – learn more and arrange your video or face-to-face consultation.
