Loss of Smell, Taste, Might Signal Pandemic Virus Infection

A loss of smell or taste may be an early indication of pandemic virus transmission, claim medical experts who present studies from a variety of countries.

It might even serve as a useful screening tool, they say.

The notion of contamination with a virus diminishing the sense of smell is not new. Respiratory virus infection is a frequent cause of odor loss, because inflammation may interfere with airflow and odor detecting capabilities. When the infection recovers, the sense of smell typically returns, although in a limited number of situations, the lack of smell will continue until all signs have gone. In some cases, it is permanent.

Currently, there is "strong data" from South Korea, China, and Italy for odor deficiency or damage of affected people claim a joint declaration from the leaders of the British Rhinological Society and ENT UK, a British association comprising physicians in the head, nose, and neck. About 30 percent of citizens in South Korea who tested positive for the virus cited the lack of scent as their main concern in others

So that might be useful as a way to spot infected people without other symptoms — fever, coughing and shortness of breath — of the new coronavirus, they wrote.

The American Academy of Otolaryngology-Head and Neck Surgery published a related recommendation Sunday. This acknowledged "rapidly growing" empirical reports from across the world that the pandemic virus may not only cause flavor loss but also a decreased sense of taste. The presence of such signs in patients without further clarification would also warn doctors to COVID-19

Maria Van Kerkhove, an outbreak expert at the World Health Organization, told reporters Monday that the U.N. health agency is looking into the question of whether the loss of smell or taste are a defining feature of the disease.

Dr. Eric Holbrook, a nasal and sinus condition specialist at Boston's Massachusetts Eye and Ear Institute, said the findings have become a hot subject for academics and physicians. Yet, he said in an interview Monday, "we don't have clear data right now" on how much scent failure occurs in people diagnosed with the pandemic virus.

Holbrook said the reports he has seen suggest the sense of smell returns within a couple of weeks, but how long it lasts has yet to be firmly established.

He also explained that evaluating evidence of a lack of taste is challenging since individuals with an affected sense of smell also experience a lack of flavor, which is clinically distinct from a taste deficiency.

Holbrook said he was attempting to set up a scent trial at Boston-area clinics of patients being screened for the coronavirus.