Fall allergies or a viral illness? Know the key symptoms

The University of Kentucky Public Relations & Strategic Communications Office provides a weekly health column available for use and reprint by news media. This week’s column is by Sarah Marks, M.D., assistant professor of Family and Community Medicine at UK HealthCare Turfland. 

LEXINGTON, Ky. (Oct. 12, 2026) — Fall allergy season overlaps with cold and flu season in Kentucky, making this a challenging time of year. Knowing how allergies differ from viral respiratory infections, such as colds and flu, can help you choose the right treatment and prevent spreading illness to others.

Why are allergies and illnesses often confused?

Different outdoor allergens are released into the air at specific times of the year. The common allergy triggers in Kentucky include ragweed, tree pollen and grass pollen. Ragweed season begins mid-August and lasts until the first harsh freeze — a primary driver of fall allergy season in Kentucky. Allergy symptoms may include a runny nose, coughing or itchy throat, nasal congestion, itchy or watery eyes, and a rash or hives.

Common viral respiratory infections and allergies share common symptoms. Although these infections can spread year-round, providers often start to see a rise in influenza (flu), RSV, the common cold and COVID-19 in late October and November. According to the Centers for Disease Control and Prevention, flu activity peaks between December and February. Across viral respiratory infections, overlapping symptoms may include cough, headaches, runny nose, sneezing and congestion.

What symptoms can help you tell the difference?

If you are trying to distinguish between allergies and the common cold, allergies commonly cause persistent itching in the eyes, nose or throat — a cold usually does not. Allergies do not cause fever or body aches like a viral respiratory infection can. Symptoms can overlap among these infections, but other common cold symptoms often include a sore throat and sometimes body aches and fatigue.  

Differentiating between the common cold and other viral respiratory infections can be trickier, so it’s important to be seen by your doctor for moderate to severe symptoms to figure out what might be making you sick. 

When is it time to see a health care provider?

Mild seasonal allergies are often well-managed at home with over the counter (OTC) options. Depending on symptom severity, treatment may include a daily or as needed antihistamine or a decongestant during allergy flares. Nasal sprays are also available to prevent swelling and reduce redness in your nasal passages.

You should see an allergist if your allergy symptoms are severe, are not controlled by OTC medication and affect your day-to-day life.

If you have a viral respiratory infection and symptoms last longer than 10 to 14 days or they suddenly return after you started feeling better, it’s recommended that you visit a healthcare provider.

Seek emergency care for serious symptoms such as trouble breathing, chest pain or pressure, confusion, difficulty waking, seizures, severe weakness or dehydration. For children, warning signs may also include bluish lips or face, ribs pulling in with each breath, or a high fever that does not respond to medication.

How can I stay healthy?

Take these steps to reduce your risk of respiratory infections and protect others:

• Discuss vaccinations with your healthcare provider. Flu shots are now available at all seven UK Retail Pharmacies.
• Practice good hygiene: Wash your hands often, sanitize high-touch surfaces, cover coughs and sneezes and avoid touching your face.
• Stay home when you’re sick. Limit contact with others and stay home from work or school when you feel unwell. If you must go out, wear a face covering to help prevent spreading illness.