Until March, when everything started to taste like cardboard, Katherine Hansen had such a sharp sense of smell that she could recreate almost any restaurant dish at home without the recipe, just by recalling the flavors and aromas.
© Jovelle Tamayo for The New York Times
Katherine Hansen used to be able to recreate a restaurant recipe just from tasting a dish. “I’m like someone who loses their sight as an adult,” she said.
Then came the coronavirus. One of Mrs. Hansen’s first symptoms were a loss of smell, and then of taste. Me. Hansen still can not taste food, and says she can not even chew it. Now she lives mostly on soup and shakes.
“I’m like someone who loses their sight as an adult,” she said. Hansen, a realtor living outside of Seattle, said. “They know what something should look like. I know what it’s supposed to taste like, but I can not get out of there. ”
A decreased sense of smell, called anosmia, has emerged as one of the symptoms of Covid-19, the disease caused by the coronavirus. This is the first symptom for some patients, and sometimes the only one. Anosmia is often accompanied by the inability to taste, and occurs suddenly and dramatically in these patients, almost as if a switch had been turned over.
Most regain their sense of smell and taste after recovering, usually within a few weeks. But in a minority of patients like me. Hansen, the loss continues, and doctors can not say when or the senses will return.
Scientists know little about how the virus causes persistent anosmia or how it can be cured. However, cases pile up as the coronavirus spreads across the world, and some experts fear that the pandemic could cause a large number of people with a permanent loss of smell and taste. The prospect has made an urgent rush among researchers to learn more about why patients lose these essential senses, and how to help them.
© Joshua Bright for The New York Times
Michele Miller developed anosmia after a fight with Covid-19 in March. She does not smell the gas from the oven that fills her kitchen.
“Many people have been doing odor tests for decades and get little attention,” said Dr. Dolores Malaspina, professor of psychiatry, neuroscience, genetics and genomics at the Icahn School of Medicine at Mount Sinai in New York, said. “Covid just turns the field upside down.”
Smell is intimately linked to taste and appetite, and anosmia often robs people of the pleasure of eating. But the sudden absence can also have a big impact on the mood and quality of life.
Studies have linked anosmia to social isolation and anhedonia, an inability to feel pleasure, as well as a strange feeling of detachment and isolation. Memories and emotions are intricately linked to smell, and the olfactory system plays an important but largely unrecognizable role in emotional well-being, said dr. Sandeep Robert Datta, associate professor of neurobiology at Harvard Medical School, said.
“You see it as an aesthetic bonus feeling,” said dr. Datta said. ‘But when someone is denied his sense of smell, it changes the way they perceive the environment and their place in the environment. People’s sense of well-being is declining. It can be really shocking and upsetting. ”
Many sufferers describe the loss as extremely disturbing, even debilitating, all the more so because it is invisible to others.
“Smell is not something we pay much attention to before it disappears,” said Pamela Dalton, who studies odor association with cognition and emotion at the Monell Chemical Senses Center in Philadelphia. “Then people see it, and it’s quite disturbing. Nothing is quite the same. ”
British scientists have studied the experiences of 9,000 Covid-19 patients who joined a Facebook support group set up by the charity group AbScent between March 24 and September 30. Many members said that they not only lost pleasure in eating but also in socializing. The loss weakened their bonds with other people, affected intimate relationships and made them feel isolated, even detached from reality.
“I feel strange about myself,” one participant wrote. “It’s also a kind of loneliness in the world. Like that part of me is missing because I can no longer smell and experience the emotions of everyday basic life. ‘
Another one said, ‘I feel upset, as if I do not exist. I can not smell my house and feel at home. I do not smell fresh air or grass when I go out. I can not smell the rain. ”
Odor loss is a risk factor for anxiety and depression, and the implications of widespread anosmia are very difficult for mental health experts. Dr. Malaspina and other researchers have found that olfactory dysfunction often precedes social deficits in schizophrenia, and social withdrawal even in healthy individuals.
“From a public health perspective, it is very important,” said Dr. Datta said. “If you think about the number of people worldwide with Covid, even if only 10 percent have a longer prolonged odor loss, then we’re talking about potentially millions of people.”
The most immediate effects may be nutritional value. People with anosmia can continue to see basic tastes – salty, sour, sweet, bitter and umami. But taste buds are relatively crude prescribers. Smell adds complexity to the perception of taste by hundreds of odor receptors that indicate the brain.
Many people who cannot smell will lose their appetite, and this poses the danger of nutritional deficiencies and unintended weight loss. Kara VanGuilder, who lives in Brookline, Massachusetts, said she had lost 20 pounds since March when her sense of smell disappeared.
“I call it the Covid diet,” she said. VanGuilder, 26, who works in medical administration, said. “It makes no sense to indulge in brownies if I can not taste the brownie.”
But as she joked about it, she added, the loss was worrying: “For a few months, almost every day, I would cry at the end of the day.”
Smells also serve as an alarm system that warns people about dangers in our environment, such as fires or gas leaks. A reduced sense of smell in old age is one of the reasons why older people are more prone to accidents, such as fires caused by leaving burning food on the stove.
Michele Miller, from Bayside, NY, was infected with the coronavirus in March and has not smelled anything since. Recently, her husband and daughter rushed her out of their house and said the kitchen was filling up with gas.
She had no idea. “It’s one thing not to smell and taste, but it’s survival,” she said. Miller said.
People are constantly searching their environments for odors that indicate changes and potential damage, although the process is not always conscious, Dr. Dalton, of the Monell Chemical Senses Center, said.
Smell warns the brain of the everyday, such as dirty clothes, and the risky, such as spoiled food. Without this form of detection, people become anxious about things, said dr. Dalton said.
Even worse, some Covid-19 survivors are bothered by ghostly odors that are unpleasant and often harmful, such as the smells of burning plastic, ammonia or feces, a distortion called parosmia.
Eric Reynolds, a 51-year-old probation officer in Santa Maria, California, lost his sense of smell when he contracted Covid-19 in April. Now, he said, he often sees bad odors that he knows do not exist. Diet drinks taste like dirt; soap and detergent smell like stagnant water or ammonia.
“I can not wash dishes, it makes me gag,” said Mr. Reynolds said. He is also plagued by ghostly scents of corn chips and a scent he calls ‘old lady perfume scent’.
It is not uncommon for patients like him to develop food disorders related to their distorted perceptions, says Dr. Evan R. Reiter, medical director of the Smell and Taste Center at Virginia Commonwealth University, who oversaw the recovery of about 2,000 Covid-19s. patients who have lost their sense of smell.
One of his patients is recovering, but ‘now that it’s coming back, she says that all or virtually everything she eats will give off a petrol odor or odor,’ said Dr. Reiter said.
The confusion of the smell can be part of the recovery process, as receptors in the nose struggle to wake up again, sending signals to the brain that are flaming incorrectly or misread, dr. Reiter said.
After the odor loss, different populations or subtypes of receptors can be affected to varying degrees, so the signals your brain becomes accustomed to when you eat steak can be distorted and can mislead your brain into thinking you are eating dog poop or something else. not nice. ”
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Patients desperate for answers and treatment have tried therapies such as olfactory training: sniffing several oils or sachets with a variety of scents – such as lavender, eucalyptus, cinnamon and chocolate – several times a day in an effort to attract the sense of smell. A recent study among 153 patients in Germany found that the training may be moderately useful for those with lower olfactory function and for those with parosmia.
Alfred Iloreta, an otolaryngologist at Mount Sinai Hospital in New York, has begun a clinical trial to see if the use of fish oil can restore the sense of smell. The omega-3 fatty acids found in fish oil can protect nerve cells from further damage or regenerate nerve growth, he suggested.
“If you have no smell or taste, you can eat nothing, and that’s a great quality of life,” said Dr. Iloreta said. “My patients, and the people I know, have lost their scent, are completely devastated.”
Mr. Reynolds feels the biggest loss when he goes to the beach near his house to walk. He no longer smells the ocean or salt air.
“My mind knows what it smells like,” he said. “And when I get there, it’s not there.”
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