Allergies, viral infections and COVID-19: How to know the difference

Springtime allergies are right around the corner, and many of our patients have already begun to notice seasonal symptoms. It can sometimes be difficult to tell the difference between a respiratory viral infection and allergies, and this is even more concerning with the current COVID-19 pandemic. A cough can be present in allergies, asthma and viral infections. However, there are a few important differences that can help to distinguish one from the other.

What are allergies?

Allergies are immune responses to things in the environment that are benign, such as pollens and animal dander. It is important to note that allergies, unlike viruses, are not contagious. There are three main manifestations of airborne allergies: allergic rhinitis, allergic conjunctivitis and asthma. Patients with allergic rhinitis can develop symptoms such as sneezing, runny nose, post-nasal drip, stuffy nose, nasal itching, sore throat, and cough. Allergic conjunctivitis typically results in red, itchy, watery eyes, and asthma can produce symptoms like cough, shortness of breath and wheezing.

Allergies are very common and present in up to 30 percent of the population. As a result, it much more likely that patients will develop a flare in allergy symptoms compared to the risk of developing COVID-19.

What are symptoms of viral infections?

The COVID-19 illness is characterized by fever, cough, and shortness of breath. There are less commonly symptoms of aches, pains, nasal congestion, sore throat or diarrhea.

Cold viruses and influenza are still circulating, and these can also produce similar symptoms as COVID-19. Cold viruses typically usually cause runny nose, sneezing, sore throat, aches and pains, as well as cough. These usually do not cause shortness of breath and rarely cause fevers in adults. The flu virus, however, can cause fevers as well as cough, sore throat, headaches, fatigue, and sometimes diarrhea. As a result, patients exhibiting these symptoms may need to be tested for influenza as well as COVID-19.

How to tell the difference between allergies and a viral infection

Allergies typically do not cause fevers. During the springtime, the main allergens are tree pollens (early spring) and grass (late spring).  Seasonal allergy symptoms usually correlate with pollen counts and often come on within minutes of going outdoors (and improve when indoors). In addition, allergies are chronic, so symptoms that have developed in the spring of previous years are likely to occur again this spring. Allergy symptoms usually come in clusters, so nasal symptoms and eye symptoms often occur at the same time. Patients with asthma also tend to develop symptoms of allergic rhinitis and allergic conjunctivitis as well.

Allergy symptoms typically respond well medications. The first step includes over the counter medications such as an oral antihistamine, an antihistamine eye drop, or a steroid nose spray. If those are not effective, prescription allergy medications can be helpful, and allergy shots (immunotherapy) can be very effective. For asthma, albuterol inhalers can treat acute symptoms, and in some patients, a prescription controller inhaler may need to be used on a daily basis.

If you are not sure about your symptoms, call your physician for instructions about what to do next.

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