Experts first recognized anosmia, or the loss of smell, as a common symptom of COVID-19 in late March. But for an increasing number of survivors, that reaction is simply the precursor to another more excruciating phenomenon — one in which the region of brain responsible for identifying smell fails to properly rebound — resulting in either distorted smells (parosmia) or phantom smells (phantosmia).
In a more than 800-person phantosmia support group on Facebook, COVID-19 survivors have begun sharing what they describe as a “depressing” battle with smells. “It has been three months since I recovered from COVID-19. Had multiple symptoms including loss of smell and taste. But a few days ago, I kept smelling burnt toast,” writes Cheryl Marais. “The past two days there is a permanent smell of gasoline.”
A separate, private Facebook group titled “COVID parosmia/anosmia support group” boasts almost 5,000 members. In interviews with Yahoo Life, more than 20 COVID-19 patients from a support group called Survivor Corps described distorted smells — such as peanut butter smelling like mold — as well as phantom smells — such as dog poop in the house of a survivor who doesn’t have a canine.
The Mayo Clinic defines phantosmia as “an olfactory hallucination [that] makes you detect smells that aren't really present in your environment,” and parosmia as when a “smell that's present in your environment is distorted.” Both seem to be linked to damage to the olfactory system, and can happen in the wake of things like sinus infections and other respiratory illnesses. Scientists still aren’t sure exactly why.
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Dr. Masha Niv, associate professor of chemical senses and molecular recognition at the Hebrew University of Jerusalem, has been studying the effect of COVID-19 on smell since March. In a study of more than 4,000 patients with smell changes, she says seven percent reported distorted smells and six percent reported phantom smells. Her results, published by the Oxford University Press this summer, suggested that both were caused by COVID-19 — and may be linked to patients’ previous loss of smell.
“Phantosmia does seem to happen following [loss of smell] that is due to other viral infections. So it isn’t surprising,” Niv tells Yahoo Life. “But the numbers are large — because COVID is so prevalent, and because anosmia is much more common in COVID compared to other respiratory illnesses.”
Claire Hopkins, a professor of rhinology at King’s College London who authored the first study on smell loss, says she has seen an increase in the number of patients with these issues. “We have just had a paper accepted for rhinology which shows 45 percent of a cohort who reported COVID loss of smell report parosmia or phantosmia within six months,” Hopkins tells Yahoo Life.
Hopkins says the change typically occurs two to three months after infection, which aligns with stories that were shared with Yahoo Life. In some cases, phantosmia seems to be fairly benign, with one survivor telling Yahoo Life that her phantom smells are “floral” in nature. Another, Jessica Bullock, says the phantom smells she experiences seem to revolve around a condiment. “Every day, multiple times a day I smell ketchup and there’s NO ketchup around,” says Bullock, a 47-year-old in Minneapolis who was diagnosed with COVID-19 in May.
But, for reasons unclear to the rhinology world, many phantom smells and distorted smells are extremely foul in nature. “For months after getting sick with COVID, I kept smelling a rotting meat or dead body smell that would come and go,” says Valarie Kenworthy, a Survivor Corps member who contracted COVID-19 in March. “I seemingly was subconsciously smelling it even in my sleep; because I had the most horrific, graphic, grotesque nightmares I've ever had.”
Parosmia can be similarly unpleasant. “I frequently smell distorted smells. The most recent was shortly after my husband mowed the yard. It should’ve smelled like freshly cut grass; I smelled a sewer leak,” says Tammy Claeson, a 49-year-old teacher in Garland, Texas, who was diagnosed with COVID-19 in July. “I get the phantom gas and sulfur smells, as well.”
Denise Tamir, a lieutenant with the NYPD, says she lost her sense of smell and taste “completely for about three to four weeks,” then experienced distorted smells when it returned. “I started smelling smoke all the time. I didn’t know where it was coming from,” Tamir tells Yahoo Life. “Another two months after that, I started smelling chemicals and my food also started tasting like chemicals. Certain smells that used to smell so nice now smell like something rotten. My laundry detergent, shampoo, conditioner, perfume — all now smell so disgusting to me.”
Hopkins says that symptoms like this are likely a sign that the brain has not fully recovered, leading to error messages in the olfactory region. But while it’s extremely uncomfortable for those experiencing it, Hopkins says the changes could ultimately be a good thing. “It appears to be related to a stage in recovery after smell loss, and so is a positive sign in long term recovery,” Hopkins says. “On non-COVID studies, phantosmia has an average duration of 12 months from time of infection but we are seeing encouraging reports of it resolving in patients around 8-9 months after COVID infection.”
For the latest coronavirus news and updates, follow along at https://news.yahoo.com/coronavirus. According to experts, people over 60 and those who are immunocompromised continue to be the most at risk. If you have questions, please reference the CDC’s and WHO’s resource guides.
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