How COVID-19 can make kissing a curse

Professor Barry Smith's team at The University of London's Centre for the Study of Senses have contributed their findings on COVID-19 and smell loss to the British Academy's 'The COVID Decade' study. 

Woman smelling flower through COVID mask
"Before COVID, post-viral infection loss or the disruption of our olfactory sense was a rare medical curiosity."

Most of us know one of the main symptoms of COVID-19 is the temporary loss of the sense of taste and smell (anosmia) with two-thirds of sufferers reporting experiencing it.

But two in five report that six months after the infection they still suffer from anosmia, or reduced sense of smell (hyposmia). Worse, one in five of these long-term cases describe familiar and usually pleasant smells such as coffee or frying onions smelling like vomit or sewage (parosmia). And for some these awful smells can linger for most of the day.

The findings are published in The British Academy’s The COVID Decade, a study by more than 200 leading academics into the effects of COVID on society over the next ten years.

The University of London’s Director of the Centre for the Study of Senses, Professor Barry Smith who contributed to the report, said: “Before COVID, post-viral infection loss or the disruption of our olfactory sense was a rare medical curiosity.

“COVID has seen a massive spike in long-term anosmia, hyposmia and, most regrettably, parosmia.

“At the moment there is no effective treatment or even a full understanding of the mechanisms causing these conditions.

“Make no mistake, these conditions are life-changing with patients unable to be intimate with their partners and repelled by their breath. The effects on daily life are profound.

“Altered eating, appetite loss, weight change, loss of pleasure in food, altered intimacy in close personal relationships and an altered relationship to self and others are just some of the consequences of these conditions.

“There are also potential risks arising from sufferers not being able to smell food that has ‘gone off’, or smell gas or burning in their homes.

“Then there is the toll on mental health and well-being. Pre-COVID research into those with olfactory disorders report high levels of depression and isolation.

“As one patient put it: ‘The world is very blank … I feel alien from myself. It’s also kind of a loneliness in the world. Like part of me is missing as I can no longer smell and experience the emotions of everyday basic living … It’s so hard to explain.’”

What matters is that researchers, clinicians and patients work together to support patients and help them manage their condition while building on their insights to guide the science.

Current thinking is that COVID-19 results in damage to the receptors that carry ‘smell signals’ to the brain and when they regenerate , receptors are missing and some are wrongly wired making, pleasant smells horrid and normally unpleasant appealing. “Fair is foul and foul is fair in parosmia, it seems”.