Before the pandemic, dr. Jennifer Spicer enjoys waking up early. In the quiet morning hours, she would spend precious alone time with her dog and make a cup of her favorite coffee with beans from a braai in Atlanta.
Now she can barely take a sip without spitting out the coffee. Once a source of palatable pleasure, her coffee now has a chemical smell and taste that Spicer can no longer tolerate.
“I can ‘t even go to a coffee shop. It smells so bad,” said Spicer, an assistant professor of infectious disease at Emory University School of Medicine. “It’s really awful.”
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The sudden change in Spicer’s senses has an all too common culprit: Covid-19. She had a relatively mild case of the virus last summer; Besides losing her sense of taste and smell, she also had fever, chills and fatigue for about a week. Her sense of smell and taste eventually returned – but not as before.
Now, Spicer said, certain foods and drinks smell and taste bad. Really bad.
“It ranges from an unpleasant chemical taste to a rotten meat taste,” Spicer said, adding that a recent bite of cheese tasted like chalk. Things are starting to improve, but it’s been almost six months since she was infected.
Spicer is far from alone. A study published Wednesday in the Journal of Internal Medicine found that 86 percent of patients with mild forms of Covid-19 have loss of sense of taste and smell, compared with 4 to 7 percent of those with moderate to severe incidents.
The research included more than 2,500 patients in France, Belgium and Italy. The majority made sense again within about two months.
Why odor and taste loss is more common in people with a milder form of Covid-19 remains unclear. The authors of the study believed that such patients have higher levels of antibodies that can limit the spread of the coronavirus to the nose.
Another attack
Covid-19 is not the first disease that leads to loss of taste or smell. A foul cold, flu, even bad allergies can cause nasal congestion which renders the senses useless. But in those cases, the use of a decongestant may help, even if only temporarily.
Not so with Covid-19, experts say. Instead, the coronavirus dulls the senses by another attack.
“It’s an inflammatory process of the nerve itself or of the cells,” said Dr. Nina Shapiro, a pediatric head and neck surgeon at the UCLA School of Medicine.
A person’s sense of smell works as follows: An odor molecule enters the nose and comes on a special tissue form called the olfactory epithelium. This tissue is filled with neurons that pick up the odor molecule and transport it through the olfactory bulb and into the brain, where it is interpreted as, for example, the scent of roses.
The neurons are guided on this journey from the nose to the brain by support cells that act as signposts and indicate the way. But the support cells are covered in a receptor called ACE-2 – the primary target of the coronavirus in human cells. This also makes the support cells a primary target.
Experts assume that the virus resides in those cells, disrupting the path for neurons to reach their destination in the brain. When this happens, people lose their sense of smell. And smell is directly related to how someone experiences taste.
There is no guarantee that those nerve connections will ever find their normal way again. But the fact that at least some reaction is taking place – even if it means that a once cherished smell now smells like chemicals – can be a good sign.
“We actually think the nerve endings are trying to grow and recover,” said Dr. Bradley Goldstein, an associate professor of head and neck surgery and communication sciences at Duke University School of Medicine in North Carolina, said. “They’re not sending the right signals yet, but things need to heal.”
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The smell and taste of food are not the only sensory problems for people who have had Covid-19. Patients also had to switch from scented soaps, detergents and deodorants.
Loss or change in sense of smell can be irritating, yes, but Shapiro points out that it can also be dangerous.
“If you have a gas leak, you can not necessarily smell it,” she said. And if people lose their appetite because food tastes like cardboard or even rotting meat, they can contract vitamin deficiencies. What’s more, people may not know when food is indeed spoiling or even burning.
The other risk, Shapiro said, is depression. People enjoy a lot of food and drink, as well as other basic principles of human happiness, such as smelling flowers.
“Your nose affects your emotional state. It helps us navigate our world and makes us feel we are in the right place,” said Dr. Sandeep Robert Datta, associate professor of neurobiology at Harvard Medical School, said.
“People who lose their sense of smell are at real risk for psychological disorders, including depression,” he said.
Spicer, who has been going after her sensory problems for six months now, advises those in similar situations to seek support groups. “Read about other people’s experiences because it makes you feel less crazy,” she said.
“Honestly, you start wondering, ‘Am I dramatic? Is it that bad?’
“Yes,” she said. “It really smells so bad.”
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