There's growing concern among health officials about so-called "silent spreaders" - people who are infected with the coronavirus but aren't sick. Now, some UK doctors say there may be a clue to who's carrying it, and they want it added to the list of symptoms.
No one knows the symptoms of the coronavirus better than those who are living with it, like 39-year-old Tara Langston who is in intensive care in London.
"Please, none of you take any chances, I mean it," she says.
But while people have been asked to watch for a fever, cough, and body aches, doctors in the UK say there's something else to look out for.
"Many of us working across the globe in areas with rising rates of COVID-19 are seeing a big spike in patients who are otherwise completely fit and well, often under 40, presenting with relatively sudden onset and complete loss of smell and taste," says Dr. Claire Hopkins, a professor and ear, nose, and throat surgeon.
Dr. Hopkins says ear, nose, and throat doctors worldwide have reported more patients with the condition over the last few weeks. Doctors caution these symptoms can be common with other viruses too, and say in the majority of cases, both senses should come back on their own.
Utah Jazz star Rudy Gobert was the first NBA player confirmed to have COVID-19. He tweeted that he hadn't been able to smell anything for four days. And a British health minister who also tested positive says she lost 100% of her taste and smell.
Doctors hope these possible clues to help diagnose COVID-19 will encourage more people to self-isolate.
"I do believe it has the potential to make a difference," Dr. Hopkins says. A new marker health experts hope may help slow the spread.
The doctors also hope this can act as a warning to healthcare workers to make sure they use full protective equipment when treating patients who've lost their sense of smell and taste.