Long Covid and Smell Disorders: what we know, and what you can do

A change or loss in smell and/or taste was one of the first symptoms reported for detecting Covid-19 during the coronavirus outbreak. It is still a key indicator of the virus (including new variants) for those who test positive. It can also have a lasting effect on people suffering with what the World Health Organisation now calls “post Covid-19 condition” or more commonly, Long Covid.
We found out more about the impact, the causes, and what can be done when we spoke to Executive Sarah Oakley from Abscent, the charity set up for those experiencing smell loss and distortion, and which aims to find a cure for these disorders. (You can watch the video and also listen to our podcast.)
The impact of this change on our daily lives is not to be undermined. We often use smells as cues for danger: to notice a gas leak or something burning but also subconsciously to recognise our loved ones or process our surroundings. Without cues like these, people can be left feeling disorientated or isolated.
WHAT ARE SMELL DISORDERS?
Our ability to smell and taste are interlinked. This is because what we know as taste is actually flavour, which comes from what we smell. So, if you lose your sense of smell, you will consequentially lose your ability to taste. It’s this loss of taste that people with Covid-19 tend to notice first.
But smelling disorders caused by viral infections are not new. In fact, there are different types of smelling disorders to know about:
Anosmia: the partial or complete loss of smell
Hyposmia: a reduced sense of smell
Parosmia: a distorted sense of smell whereby pleasant smells trigger repulsion or nausea
Phantosmia: the smelling of things that are not there e.g. burnt toast
Many people who test positive for Covid-19 report feeling like their ability to smell and taste is suddenly switched off, or that it has become changeable. Others start to notice unusual smells like burnt rubber and cigarette smoke. It is currently not known what causes these smells and research is ongoing to understand it. But it is extremely common among those with a Covid infection or Long Covid symptoms. Some figures suggest that over 260,000 people in the UK will experience smell loss or distortion as a result of the coronavirus.
WHAT CAUSES SMELL DISORDERS?
More research on smell disorders is needed to fully understand them. Studies into the biology of smell disorders will take time and analysing their effects on Covid-19 patients will take multiple years. What we do know is that some people are more susceptible to losing their sense of smell and taste from a virus than others. But we don’t know why.
Public awareness of smell disorders today is higher than ever and people are recording their experiences more frequently due to the disorder’s prevalence throughout the pandemic. This recognition should help to speed up the learning process and address smell disorders as an issue.
Above: covid:aid spoke to Abscent's Sarah Oakley for a Community-hosted Live Q&A
HOW DO YOU TREAT THEM?
There are no medical treatments or medicines for smell disorders at present. Instead, our bodies just need time to heal.
However, research shows that smell training can help. Smell training involves taking a sample of a familiar fragrance, like lavender, holding it to your nose for two sniffs and repeating the process twice a day for three or four months. It is a simple but slow process. Nevertheless, it can speed up recovery time by one third if practised regularly.
Sarah Oakley, the executive director of AbScent, a UK charity that supports people with smelling disorders, explains that the chosen scent doesn’t have to be expensive. She suggests using a strong smelling shampoo because when we think about the action of washing our hair while we sniff, we are “strengthening the pathway between the nose and the brain, meaning you will recover your sense of smell more quickly.”
Peer support is another thing that can help to deal with the alienation caused by smell disorders. “It’s quite life changing really,” Sarah explained to us. “When you can’t taste anything and when you can’t smell anything, you don’t interact with people in the same way because you’re not picking up on the same signals as them.” It’s important for this reason to connect with other people who are experiencing the same thing. AbScent provides various support networks and Facebook groups you can join on their website.
HOW LONG WILL IT LAST?
Over 70% of people that lose their sense of smell and taste from Covid will get it back within a month. But for the remaining 30% it could become a long term issue or get worse. This is because the virus attacks the sustentacular cells which support the olfactory neurons (smell receptors) in our noses – thus affecting our ability to smell. The good news is that these cells are designed to grow back, but the healing process takes time. For some, this could mean their smell returning after six to twelve months; for others it may take two or three years.
What happens next for those who have had Covid-19 is that when their sustentacular cells start to regrow, the parosmia (distorted sense of smell which causes nausea) begins. This is because the new, younger cells are learning and adapting to different smells which results in previously enjoyed smells like coffee – now unfamiliar to the cells – triggering an intense disgust response in the body. Fortunately, this severe kind of parosmia won’t last forever but it can be difficult to deal with for a time.
It’s important to remember that your sense of smell could vary, and this is very common after a Covid infection. As Sarah says, ‘Recovery doesn’t happen in a straight line […] you’re going to have some good days and some bad days. But fluctuations are a normal part of the experience.”
WHAT TO DO IF A SMELL OR TASTE DISORDER AFFECTS YOUR APPETITE?
It’s possible that a loss in taste or smell can affect our appetites. The advice if this happens is to try to focus on other aspects of the food we might enjoy. Paying attention to the temperature, texture, or colours on the plate helps to stimulate our senses during a meal and will encourage us to take in enough calories each day. If you find that certain smells are making you nauseous, try to understand what the triggers are: start with bland foods like bread or pasta and eat smaller portions sizes to gently build up an appetite.
As time goes on and our smells and tastes return, we can begin to reintroduce more foods into our diets. The main thing is to be aware of your own body and your own responses.
MORE INFORMATION
For more information on this topic, please listen to our live Q&A with Sarah Oakley from AbScent or find the resources listed below. If you have more questions or would like support in relation to Covid-19 or Long Covid, please join the covid:aid Support Community where we share advice, information and support on a range of subjects.
Resources
covid:aid podcast Q&A with AbScent: shows.acast.com/covid-matters/episodes/long-covid-smell-loss-disorders-abscent
AbScent: abscent.org/
covid:aid Support Community: community.covidaidcharity.org/feed
NHS website: nhs.uk/conditions/lost-or-changed-sense-smell/
Fifth Sense: www.fifthsense.org.uk/smell-training/
Photo by Elly Johnson on Unsplash
Published 14 November 2021
Sheryl Henderson
Head of Content at covid:aid