In the era of COVID-19, there are few sounds more anxiety-inducing than a hacking cough or explosive sneeze from a nearby stranger.
The coronavirus, like other respiratory diseases, can easily spread through tiny droplets from an infected person’s cough or sneeze.
But just because a person sounds ill, it doesn’t mean they are, a new report from American researchers at the University of Michigan says.
During four studies, researchers tested a person’s ability to judge if someone was infected with a communicable disease based on the coughing and sneezing sounds they made.
Given about 15 per cent of human deaths around the world are caused by infectious and parasitic diseases, it makes sense that our ears would be trained to detect sounds that might signal a pathogen threat.
No such luck.
It turns out our ears are much better at tuning into the sound of a crying baby or wailing siren than identifying disease.
The researchers found no evidence the listeners could accurately identify infectious agents from coughing or sneezing sounds, even if the participants felt certain they could.
Instead, the more disgusting they believed a sound to be, the more likely they were to judge that it came from an infected person – even if it didn’t.
“Our research suggests that when people guess whether a cough or a sneeze comes from an infected person, they only get it right about half of the time – consistent with chance accuracy (like flipping a coin),” the scientists wrote.
“Despite poor accuracy, participants were often very certain that they guessed correctly.
“Our findings suggest that people are not very good at identifying infection from coughs and sneezes alone.”
The study’s authors concluded that the next time you hear someone cough or sneeze, “perhaps leave the diagnosis to the doctor”.