Harvard researchers discover why COVD-19 causes loss of smell


One of the many mysteries of COVID-19 can finally be solved.

Researchers from Harvard Medical School say they discovered why some people infected with the coronavirus lose their sense of smell.

The symptom, called “anosmia” by doctors, is one of the first and most frequent indicators of the virus.

Some studies suggest that it might actually be a better way to predict if you have the disease than other symptoms known as fever and cough.

But, until now, scientists have been baffled exactly how some patients were being robbed of their senses.

The researchers set out to better understand how odor is altered in coronavirus patients by identifying the cell types most vulnerable to SARS-CoV-2, the virus that causes COVID-19.

Through their analysis of various data sets, they discovered that it attacks cells that support olfactory sensory neurons, which detect and transmit smell to the brain.

“Our findings indicate that the new coronavirus changes the sense of smell in patients not by directly infecting neurons but by affecting the function of supporting cells,” said Sandeep Robert Datta, professor of neurobiology at Harvard Medical School and co-author of the article. .

That means the virus is unlikely to permanently damage olfactory neural circuits, meaning patients can regain their sense of smell, the scientists said.

“I think that is good news, because once the infection clears up, olfactory neurons don’t seem to need to be replaced or rebuilt from scratch,” Datta said in a statement.

But, he added, “we need more data and a better understanding of the underlying mechanisms to confirm this conclusion.”

Their study was published Friday in the peer-reviewed journal “Science Advances.”

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