Study confirms loss of smell and taste as a symptom of COVID-19

Posted at 12:49 PM, Apr 28, 2020

Back when COVID-19 testing was in its early stages, Kai Halsey-Mendez had to wait a week before he was officially diagnosed. He was diagnosed on April 1, but started experiencing symptoms of the disease on March 23.

“It was really just dizziness and severe fatigue. Just feeling really tired and kind of out of it,” Halsey-Mendez said.

Then a couple days later, he started experiencing more symptoms.

“One of my roommates actually brought up the smell of something that was cooking. I was like ‘man I can’t really smell anything’ and that was right when everybody was talking about that being a symptom,” Halsey-Mendez said.

Halsey-Mendez had heard on the news that some people with COVID-19 were losing their sense of smell and taste. So, he put his olfactory system to the test.

“I went and sprayed some Lysol on my hands and tried to smell that – couldn’t smell that. Went and started sniffing some bottles of alcohol we have – ya know obviously there are certain alcohols that are pretty potent that will make you take back – I had nothing.”

Candles, foods, exhaust from cars – he couldn’t smell anything. Then one day later, he lost his sense of taste.

“Whiskey, water, salsa, anything just went down – you got the texture, but not the taste.”

For many weeks, loss of smell and taste was a suspected symptom, but there was only anecdotal evidence. It inspired researchers to question it more. That led Rhinologist Carol Yan to conduct a study at UC San Diego.

“In our study we found that if you have smell and taste loss, you’re 10 times more likely to have COVID-19 than other illnesses and viruses going on right now,” Dr. Yan said.

According to Dr. Yan, the study proves smell and taste loss is a confirmed symptom of COVID-19. She says other reliable studies have shown the similar results and now the CDC is listing it as an official symptom.

“Anyone who calls with concerns of symptoms of COVID-19, they’re now being screened with the question: do you have any sudden loss of smell and taste?"

Dr. Yan says loss of smell and taste isn’t unique to the SARS-coV-2 virus.

“We know that over 200 viruses – the common cold viruses, the flu – can cause smell and taste loss,” Dr. Yan said.

However, there’s something peculiar about sensory loss with this virus. Halsey-Mendez says he didn’t have any congestion or respiratory symptoms at all. And the loss of smell and taste came after his fever had subsided.

"A lot of times people with allergies can have some decreased sense of smell and taste as well, and it’s usually associated with what we’d consider inflammation and stuffy nose or congestion," Dr. Yan said. "And what we found is that in COVID-19, very few people report associated nasal congestion or stuffy nose along with it. So, it kinds of hints that maybe the way the virus is attacking our sense of smell and our smell fibers in the nose might be completely different than other viruses.”

Dr. Yan says researchers are still questioning how the virus is causing sensory loss. She says it could be targeting nerves, the olfactory bulb, the cells around the nerves or it’s localized inflammation. Nonetheless, a new study is showing people who do experience this symptom are much more likely to have a mild case.

“People who are positive for COVID-19 who have smell and taste loss are less likely to require hospitalization than those that don’t.”

That was certainly the case for Halsey-Mendez. He says he only had a bad fever and fatigue for two days. He was already feeling better by the time he lost his sense of smell and taste – which then came back again after a few days.

“It’s weird how the symptoms for everybody seem so different. Some people are having these severe life-threatening symptoms, and others don’t even know it,” Halsey-Mendez said.

Dr. Yan says these findings about sensory loss will help us to understand how severe of a case a person may have, and more people will know they could potentially have COVID-19 hopefully encouraging them to quarantine themselves to stop the spread.

“Honestly if there wasn’t a big awareness and all of this wasn’t going on, I probably would have thought I had a head cold or sinus infection or something weird like that,” Halsey-Mendez said.