Millions of people experience lingering COVID-19 symptoms long after their infection subsides, including loss of taste and smell. But it’s unclear if and when affected people will recover their senses.
Now, new research reveals just how widespread the burden may be.
Estimates from the Washington University School of Medicine in St. Louis suggest between 700,000 and 1.6 million people in the U.S. are experiencing chronic smell loss or distortion because of COVID-19, according to a study published Nov. 18 in the journal JAMA Otolaryngology–Head & Neck Surgery.
The approximations were based on the likelihood someone loses their sense of smell from COVID-19, projected recovery rates from “olfactory dysfunction,” and the number of daily COVID-19 cases reported between January 2020 and March 2021 by The COVID Tracking Project.
Researchers admit the true number of people experiencing chronic smell loss or distortion “may be far higher” than they report because many COVID-19 cases may have gone unnoticed, particularly those that don’t cause symptoms. The estimates were also based on healthier patients, not those who were hospitalized, which could mean loss of smell is more common than studies suggest.
The team calls coronavirus-related smell loss a “growing public health concern,” given it can decrease quality of life, negatively impact diet, increase anxiety about personal hygiene and trigger depression.
What’s more, loss of smell can put affected people and their loved ones in danger, stripping their ability to detect harmful gases and smoke in the air.
What is parosmia?
Included in the projections are those who suffer from parosmia — a change in the normal perception of odors that can distort pleasant smells into foul ones. Often, people first lose their sense of smell and taste then go on to develop the condition.
Experts don’t yet know why COVID-19 leads to parosmia and how long it lasts, but one study suggests it can persist for up to six months and linger for an average of three.
“Parosmia can be caused by a number of things such as respiratory infections, seizures, and even brain tumors,” Dr. Richard Orlandi, an ear, nose and throat physician and professor of surgery at University of Utah Health, said in a blog post. “We’ve noticed since the pandemic more COVID-recovered patients now report this symptom.”
“Right now, so little is known about the long-term effects of COVID-19,” Orlandi added. “All we really know is that the majority of patients do experience a return of their normal senses of taste and smell, but it’s unclear if and how many patients will get fully back to normal.”
People who developed parosmia after COVID-19 are sharing their experiences on the social media platform TikTok. Comment sections alone reveal how common the condition really is.
One TikTok user has shared over a dozen videos chronicling her diagnosis. She said her sense of smell and taste returned after disappearing sometime during her coronavirus infection back in September 2020, but then she developed parosmia in late November 2020.
A year later, she’s still suffering from the condition, admitting most food is “completely unbearable” without a nose clip and she can’t “get it down without feeling sick.”
“Imagine walking into a restaurant and it just smells like they’re burning trash. Imagine going out during a rainstorm and the rain smells like chemicals. Imagine Thanksgiving dinner and it smells like everyone’s burning gasoline on top of the food,” TikTok user @shleeeeeeeeee, whose profile says her name is Ashley Zibetti, said in one of her videos. “There’s no joy associated with any kind of smell at all anymore.”
Zibetti, who’s also pregnant, said she has to hold her breath just to hug or kiss her husband. She said she’s “had so many days where I’ve just broken down crying over this. I literally couldn’t tell you if my house was burning down or if my husband was cooking dinner.”
Orlandi of the University of Utah Health said parosmia can “range from an annoyance to a frustrating and anxiety-inducing symptom.”
“Your sense of smell is important. It’s what helps you enjoy food and sense danger, as in the case of smoke,” Orlandi said. “It’s connected to our memories, such as the way your mom or grandma’s perfume smells.”
Other TikTokkers have shared similar experiences.
Commenters reveal they’re in the same position. Some say “lemons taste like citronella candles and chocolate tastes like burnt coffee” and others say they smell cigarette smoke everywhere they go.
There’s no treatment for COVID-related parosmia yet. Some experts say “smell therapy” could help — the process of smelling strong scents every day to train the brain to remember them — however more research is needed to confirm if it works.Some clinical trials are underway to discover potential treatment options.