Could it be coronavirus, or is it just allergies? Here's how to tell

Spring is upon us, bringing warm weather, sunny skies, flowers — and, for those with seasonal allergies, coughing, itchy eyes, and stuffy noses. This year, though, allergy season coincides with the novel coronavirus outbreak, which has infected more than 113,000 people worldwide as of March 10, CNN reports. The tricky thing is, the disease caused by novel coronavirus, COVID-19, can cause symptoms that resemble those of seasonal allergies. So how can you tell whether you have allergies or coronavirus?

Let’s start with seasonal allergies, which tend to strike in the spring and fall, according to Reynold A. Panettieri, Jr., a professor of medicine at Rutgers Robert Wood Johnson Medical School. He says the most common symptoms are itchy eyes, a runny nose, swollen sinuses, sneezing, and coughing. If you have asthma, you might experience a worsening of asthma symptoms, with wheezing, for instance. The acute onset of these symptoms lasts around three to four days, although milder symptoms, like sniffles, can last for a month or two. “They typically wax and wane,” Panettieri tells Mic. They might subside after it rains, since raindrops can jostle pollen out of the air, or at the beach, where there’s less pollen.

Although allergies and COVID-19 share symptoms, they work through different biological mechanisms

Viruses are often worse in the winter, Panettieri explains, although whether the same applies to the novel coronavirus remains unclear. Symptoms of COVID-19 include coughing, shortness of breath, and fever. “You don’t get a fever from allergies,” Panettieri says. COVID-19 can also lead to pneumonia, which may cause wheezing and a cough that brings up green or yellow phlegm. COVID-19 symptoms last longer than allergy symptoms — around two to three weeks. “It crescendos,” Panettieri says. “It gets mild, then worse and worse.”

Although allergies and COVID-19 share symptoms, they work through different biological mechanisms. (Here’s where it gets a little nerdy.) You get allergies when your body becomes sensitized to pollen or other allergens, Panettieri explains. Allergens bind a special class of proteins in the blood, which then activate a group of cells in the lining of the airways.

These cells, in turn, release compounds that trigger the inflammation that underlies hallmark allergy symptoms, such as itchy eyes and clogged sinuses. COVID-19, on the other hand, is an infection that causes inflammation mainly in the airways and lungs. Unlike allergy symptoms, COVID-19 symptoms worsen because the coronavirus continues to grow and destroy the tissue lining these respiratory regions.

Since we’re still in flu season — which spikes between December and February, but can stretch into late May, according to the Centers for Disease Control and Prevention — it’s worth noting that flu can look like COVID-19, Panettieri says. Cough, shortness of breath, and fever can occur with both flu and COVID-19, per CBS News.

Again, “the important takeaway is to realize fever doesn’t occur with allergy,” Panettieri says. If you have a fever accompanied by a cough and shortness of breath, even if you’re not sure what’s causing your symptoms, isolate yourself, stay hydrated, and notify your health provider. Call them beforehand, rather than just walking into the clinic, which may expose people to infection, per CNN. The overlap of allergy season and the coronavirus outbreak may feel confusing, even scary, but a little mindfulness about your symptoms can prevent an unnecessary doctor visit while also ensuring you get the care you need and keeping those around you safe.