A doctor conducts a Covid-19 test on a teacher. Researchers are still finding new symptoms of the disease. | Sebastian Gollnow/Picture Alliance via Getty Images

Scientists say they still have more to learn about the symptoms of Covid-19 infections, long Covid, and the new variants.

It’s been more than a year since Covid-19 landed in the United States. And the once-perplexing array of symptoms like coughing, fever, shortness of breath, and loss of taste and smell are now very familiar to doctors around the country.

The range of possibilities when someone shows up to a doctor’s office with new respiratory symptoms “is very, very narrow these days,” said Anish Mehta, medical director for clinical quality and virtual health at Eden Health, and an assistant clinical professor of medicine at the Icahn School of Medicine at Mount Sinai. “It’s probably Covid if