As anecdotes continue to crop up, the medical community is still putting all the pieces together. When asked last week about scattered reports around the loss of taste and smell, Greg Poland of the Mayo Clinic said the news accounts raised questions but didn’t necessarily qualify anosmia as an official symptom of infection with SARS-CoV-2.

“There have been no reports in the medical literature, that I’m aware of, in terms of widespread loss of smell and taste,” Poland said at the time. “Having said that, respiratory viruses…can cause sinusitis—which certainly can cause loss of smell.”

Sinusitis is when cavities around the nasal passages become inflamed. That inflammation can inhibit a person’s ability to smell—also known as anosmia. And because our senses of smell and taste are interconnected, sinusitis could also play a role in reported distortion of the sense of taste—so-called dysgeusia.

At a major hospital in Atlanta, Georgia, Antoinette Ward is a nurse practitioner leading the testing of Covid-19 for her institution. She said much of what we know about Covid-19 is evolving, and that includes the symptoms medical professionals look out for when new patients come to them.

“A lot of people are experiencing nausea and diarrhea, so we’re all learning about the disease process and how it affects people,” Ward said. “I’ve definitely heard [from patients] about the loss of smell, I have not specifically taken care of a patient who has complained of a loss of taste.”

Both of those accounts came before some mainstream medical associations began to communicate about the taste and smell loss to their member. On Sunday, the American Academy of Otolaryngology posted onto its website a recommendation that medical professionals treat loss of taste and smell as symptoms of Covid-19.

“Anecdotal evidence is rapidly accumulating from sites around the world that anosmia and dysgeusia are significant symptoms associated with the Covid-19 pandemic,” the group said in its statement.

Two medical groups in the United Kingdom, the British Rhinological Society and ENT UK, issued a joint statement about the loss of smell being a symptom.

A representative with the World Health Organization today (March 23) said the group has seen many reports of loss of the two senses, and has started looking into whether it’s connected to the virus.

The development shows how the medical community is being asked—in real time—not only to respond to the health crisis on the ground, but also to step back and notice global trends. It’s a reminder that the evolution of medical knowledge is a very human process, filled with trial-and-error, patience, and diligence.

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