Is It Covid, Spring Allergies or a Cold?

As summer approaches, many people with spring allergies are still suffering. And as new Covid variants circulate, experts say we may also soon see an uptick in cases. (Though wastewater data suggests that Covid cases are currently fairly low.)

It can be tricky to distinguish between seasonal allergy symptoms, early signs of the coronavirus or just a run-of-the-mill cold.

The clearest way to get an answer is to take a Covid test. But at-home rapid tests have become more difficult to get a hold of since the public health emergency expired. Here are other tips to help you identify the source of your suffering.

Watch out for specific symptoms

Some people with Covid can experience the worst symptoms during, say, their third infection compared to their first two. But in most cases, the more immunity someone has built up — through repeat infections, vaccinations or a combination of the two — the milder Covid symptoms tend to be.

“In most people, it’s the sneezy, stuffy nose — it’s like my allergies, for sure,” said Dr. Davey Smith, an infectious disease specialist at the University of California, San Diego.

People with allergies rarely develop high fevers; if you are running a temperature above 100.4 degrees it’s more likely to be Covid or another viral infection, said Dr. Purvi Parikh, an allergist and immunologist at NYU Langone Health.

Covid can also cause an upset stomach, leaving people with nausea, vomiting and diarrhea, all of which are usually not present with allergies. And unlike people with seasonal allergies, those with Covid often experience body aches as well, said Dr. Lily Pien, an allergist at the Cleveland Clinic.

Allergies tend to make people itchy, so if you’re scratching at your eyes, ears and throat, it’s much less likely to be Covid. Another key difference is that allergies cause “dry” symptoms, Dr. Parikh said, meaning that allergy-related coughs typically won’t produce mucus.

Both allergies and viral infections can wipe you out, but with Covid, fatigue comes on more suddenly, Dr. Parikh said. “It’s not like ‘I’m a little tired, I need a nap’” she said. “It’s usually very debilitating.”

Time and context matter

Obviously, if you have spent time with someone who later tested positive and now you can’t stop sneezing, there’s a good chance you, too, have Covid. On the other hand, if you develop allergy symptoms every spring and started sniffling like clockwork when the trees began to bloom, you can be fairly confident that allergies are the cause of your discomfort.

However, it’s possible for allergy symptoms to suddenly “turn on” in people who didn’t have them before, Dr. Pien said. Moving to a new place can also expose you to new pollens and longer growing seasons, which could trigger an allergic reaction.

Doctors advised paying attention to how long you feel sick: If your sniffles stick around for weeks on end, it’s likely allergies, said Dr. Paul Sax, the clinical director of the division of infectious diseases at Brigham and Women’s Hospital. (That said, Covid can also make you feel sick for weeks on end, even outside of “long Covid.”)

And see whether allergy medications, like antihistamines and nasal steroid sprays, alleviate your symptoms. If so, allergies were probably the culprit.

Still, doctors stressed, the only surefire way to figure out the source of symptoms is with a test.

“Even I’ve been fooled,” Dr. Parikh said. “On some of my patients, it’s identical, until we get through the Covid test.”