Flu Prevention & Care Symptom Comparison Chart COVID-19, the flu, a cold or allergies?It’s the beginning of cold, flu and allergy season, and this year, we also need to watch for COVID-19. It can be difficult to know what you’re fighting, though, as their symptoms can look very similar. This chart can help you decide when and where to seek care for your symptoms. Symptoms COVID-19 Cold Flu Allergies Symptoms Symptoms onset after exposure COVID-19 Mild to severe; begin 1-14 days after exposure Cold Gradual onset; begin 1-3 days after exposure Flu Abrupt onset; begin 1-4 days after exposure Allergies Improve or worsen based on environment; begin immediately after exposure Symptoms Fever COVID-19 Common Cold Rare Flu Common Allergies No Symptoms Fatigue, weakness COVID-19 Sometimes Cold Sometimes Flu Common Allergies Sometimes Symptoms Exhaustion COVID-19 Sometimes Cold No Flu Common Allergies No Symptoms Aches and pains COVID-19 Sometimes Cold Sometimes Flu Common Allergies No Symptoms Cough COVID-19 Common Cold Common Flu Common Allergies Sometimes Symptoms Sneezing COVID-19 Rare Cold Common Flu Sometimes Allergies Common Symptoms Runny or stuffy nose COVID-19 Rare Cold Common Flu Sometimes Allergies Common Symptoms Sore throat COVID-19 Sometimes Cold Common Flu Common Allergies Sometimes Symptoms Diarrhea, nausea or vomiting COVID-19 Sometimes Cold No Flu Sometimes (in children) Allergies No Symptoms Headache COVID-19 Sometimes Cold Rare Flu Common Allergies Sometimes Symptoms Shortness of breath COVID-19 Sometimes Cold Rare Flu Rare Allergies Common Symptoms Itchy eyes COVID-19 No Cold No Flu No Allergies Common Symptoms Itchy nose or throat COVID-19 No Cold No Flu No Allergies Common Symptoms Loss of taste or smell COVID-19 Sometimes Cold No Flu No Allergies No