Some symptoms of COVID-19, the disease caused by the new coronavirus, overlap with those of the common cold, allergies, and the flu. That can make it tricky to diagnose without a test.
Even President Donald Trump asked pharmaceutical executives earlier this month if the flu vaccine could be used to stop the coronavirus. (The answer is no, but it's still good to get a flu shot to lower the chance that you get the flu and take up crucial healthcare resources.)
The coronavirus primarily affects the lungs and commonly causes fever, a dry cough, and shortness of breath.
Here are the symptoms associated with COVID-19 and how they compare with symptoms of the common cold, the flu, and allergies:
If Your Nose Is Running, You Probably Don't Have COVID-19
COVID-19 can be most easily distinguished from colds, allergies, and the flu based on a trifecta of symptoms: fever, dry cough, and shortness of breath. That last symptom is not associated with colds or the flu, though it is common for allergies.
If you're sneezing and have a runny nose, it's unlikely that you have COVID-19. The flu is also more likely than COVID-19 to come with aches and pains.
Diarrhea is a rare symptom of COVID-19, but gastrointestinal symptoms like nausea and diarrhea could be early clues of infection, a growing body of preliminary research has found. It's also a symptom mostly unique to people with COVID-19 and some children with the flu.
Still, the overlap between symptoms of COVID-19 and those of other common conditions is in part why widespread testing is necessary.
Some countries, like China and South Korea, have tested hundreds of thousands of people. But according to the COVID Tracking Project, a test-tracking resource from two journalists at The Atlantic and the founder of a medical-data startup, only about 8,000 tests have been run in the US. They noted, however, that those figures may be incomplete because of different states' policies on reporting negative tests.