13 Things Scent-sational News About Smell

In early 2020, ear, nose, and throat doctors around the world saw an unusual number of patients who had unaccountably lost their sense of smell. Many of these specialists then developed the same condition, and some became very ill. Suddenly, the stepchild sense took center stage.

- By Emily Goodman

1 When Americans were asked in 2018 which sense they would miss most if they lost it, smell came in dead last—only 2 percent of respondents picked it. Then came COVID-19. In early 2020, ear, nose, and throat doctors around the world saw an unusual number of patients who had unaccountably lost their sense of smell. Many of these specialists then developed the same condition, and some became very ill. Suddenly, the stepchild sense took center stage.

2 Researchers soon realized that smell loss is a leading indicator of COVID-19. Those infected with the virus are 27 times more likely than noninfected people to exhibit smell dysfunction—but only two and a half times more likely to run a fever. Some public health experts started proposing using smell tests—not temperature checks—to screen people for the virus.

3 Scientists still don’t fully understand the link between smell and COVID-19. While they know that patients who don’t lose their sense of smell are more likely to be hospitalized and placed on a ventilator, they don’t know why. Perhaps most worrying, they don’t know whether this virus’s adeptness at invading noses indicates similar skill at invading brains. (The smell receptors at the top of our noses are connected to the base of our brains.)