Along with a fever and cough, it is one of the defining and most surprising characteristics of Covid-19: the loss of your sense of smell. It’s usually accompanied by an inability to taste anything, as the two senses are intrinsically linked.
In many cases the problem resolves itself in a matter of weeks. However, half the people who catch Covid may suffer long-term changes to their senses, according to preliminary studies.
Researchers at the Karolinska Institute in Stockholm ran tests on 100 people who had lost their sense of smell after a bout of Covid in March 2020 and found that, 18 months on, almost one in 20 had regained nothing whatsoever.
Previous research suggested a similar number were still suffering this deceptively unpleasant symptom six months after recovering from their initial illness. But the newly published findings indicate that, in a significant minority, it may endure even longer.
Half the people who catch Covid may suffer long-term changes to their senses, according to preliminary studies.
Last week The Mail on Sunday’s GP columnist Dr Ellie Cannon asked readers if they had suffered long-term difficulties, and we were flooded with responses. Many readers were desperate for a solution, having received no answers from multiple specialists, while others had tried to fix the problem themselves with nasal sprays and sinus rinses. Many people fear their senses will never return to normal.
Claire Carter-Humphreys, 46, from Bromley in South-East London, caught Covid nearly 16 months ago and says her sense of taste and smell haven’t been the same since.
The administrator, who lives with her husband and 15-year-old son, came down with the virus in October 2020 and, at its worst, she struggled to breathe and suffered intense headaches.
She says: ‘A few days after I tested positive, my sense of smell and taste began flicking off and on like a light switch. At times I couldn’t taste or smell anything, then the very next moment I was getting these horrible smells like sewage and rotting meat.
‘To this day, my senses have never really recovered.’
Claire says her diet has also been affected. ‘I tend to stick to the same food that I know won’t smell awful and I’ve lost quite a bit of weight.’
Worst of all for Claire, while doctors have recommended numerous treatments – including smell training, which is actively sniffing strong odours regularly in a bid to reactivate the senses – nothing seems to make any difference. ‘I really long to have my sense of smell back,’ she says. ‘I’m holding out hope it will return eventually, but I’m worried there’s nothing doctors can do for me.’
Claire is not alone. Other readers shared their experiences of smell training, which is the first treatment that GPs will recommend to tackle the problem.
readers shared their experiences of smell training, which is the first treatment that GPs will recommend to tackle the problem
‘I caught Covid in December 2020, and now, 13 months on, I still can’t smell anything and can barely taste a thing,’ says Richard Tacon, 72, a farmer from Norfolk.
Richard read about smell training and tried sniffing lemons, roses, cloves and eucalyptus every day for several months, but says: ‘Unfortunately it was to no avail.’
Some say the condition has worsened over time.
‘Since I first had the virus, my smell and taste have gradually faded,’ says Keith Webster, an electrician from Chepstow in Wales who caught Covid in November 2020. ‘I’ve now reached the point where all foods pretty much taste the same, and at times I can smell a strong detergent-type odour.’
Others say their loss of smell and taste has lasted so long that it has changed the way they eat.
‘My idea of enjoying food now is going by its texture rather than its taste,’ says Mandy Copeland, who got Covid in April 2020.
Loss of smell or taste are not uncommon symptoms for people suffering with respiratory viruses such as colds and flu. This is partly because swelling in the throat and nose can disrupt smell and taste receptors. But sometimes the viruses can also damage small nerves in the nasal passage, drastically reducing sensation even after the virus has left the body.
Loss of smell or taste are not uncommon symptoms for people suffering with respiratory viruses such as colds and flu. This is partly because swelling in the throat and nose can disrupt smell and taste receptors
Studies looking at smell and taste loss caused by colds show that some patients can take years to fully recover their senses
As these nerves recover, some return to full strength at different speeds than others, which leads to a distortion in smell. Studies looking at smell and taste loss caused by colds show that some patients can take years to fully recover their senses.
Professor Carl Philpott, a smell and taste-loss expert at Norwich Medical School, says while there is some evidence that Covid causes more severe loss of sensation, the symptoms he sees in patients are nearly identical to those found in pre-pandemic patients.
He says: ‘Viruses have long been known to cause smell disturbances, but the sheer scale of Covid infections is so high that this problem has become much more noticeable. I am still getting several hundred new patients referred to me every month, all of whom are struggling with smell and taste issues.
‘Most of these patients caught Covid before the vaccines arrived, which suggests the jabs might be reducing the level of smell and taste loss, but it’s also a sign of just how many people were impacted.’
In the UK, smell training has long been the treatment for all virus-related smell and taste loss. A US study of 140 Covid patients with smell loss found that sniffing at least four distinct odours twice daily for two months could improve subjects’ sense of smell. However, experts say a significant number of their patients find smell therapy ineffective and that there is a desperate need for new treatments.
Prof Philpott says: ‘People don’t realise how debilitating losing your smell and taste can be. Not being able to enjoy a single mealtime drastically impacts sufferers’ relationships and social lives. Smell training doesn’t work for everyone, so we need something else to stop patients spiralling into depression, which is not too uncommon.’
Some doctors are also exploring whether Vitamin A nose drops could help reverse the damage, after a German study published last April found taking them regularly for eight weeks sped up recovery for 14 per cent of participants.
Experts believe the compound is capable of kick-starting the repair of damaged sense receptors in the nose. Numerous readers say they are already trying it at home. ‘I’ve been using the drops for about two months now,’ says Richard. ‘I haven’t seen any improvement yet but I’ve got my fingers crossed it’ll help.’
For many people, the recovery process is mainly a matter of time and patience
For many people, the recovery process is mainly a matter of time and patience.
‘It can sometimes take up to three years for smell and taste to return to normal levels – we see this with colds,’ says Prof Philpott. ‘Often recovery occurs out of nowhere, with no treatment.’
For a small number of people, however, the condition can be permanent. MoS reader Phil Brooks, 70, from Derbyshire, suffered a ‘bad head cold’ eight years ago and has been able to smell or taste virtually nothing since. ‘Occasionally I’ll pick up a smell, like lilies or bonfire smoke, but most of the time I can’t smell a thing,’ he says.
The number of Britons suffering loss of smell or taste has also decreased since the arrival of Omicron in December 2021.
According to researchers at King’s College London, less than a fifth of people infected with the variant now suffer the symptoms.
This is due largely, it is believed, to the UK’s high level of vaccination, but also because Omicron is a milder version of the virus.