Symptoms
COVID-19 A single asterisk: Information is still evolving
Symptoms range from mild to severe
ColdGradual onset of symptoms
FluAbrupt onset of symptoms
Seasonal AllergiesAbrupt onset of symptoms
Length of symptoms
7-25 days
Less than 14 days
7-14 days
Several weeks
Fever
COVID-19 Fever common
Cold Fever common
Short fever period
Flu Fever common
Seasonal allergies Fever no
Cough
COVID-19 Cough commonUsually dry
Cold Cough common
Mild
Flu Cough commonUsually dry
Seasonal allergies Cough rareUsually dry
Difficulty Breathing
COVID-19 difficulty breathing common
Cold difficulty breathing no
Flu difficulty breathing no
Seasonal allergies difficulty breathing no
Shortness of Breath
COVID-19 Shortness of Breath sometimes
Cold Shortness of Breath noAllergies, colds, and flus can all trigger asthma, which can lead to shortness of breath.
Flu Shortness of Breath noAllergies, colds, and flus can all trigger asthma, which can lead to shortness of breath.
Seasonal allergies Shortness of Breath noAllergies, colds, and flus can all trigger asthma, which can lead to shortness of breath.
Sneezing
COVID-19 Sneezing no
Cold Sneezing common
Flu Sneezing no
Seasonal allergies Sneezing common
Sore Throat
COVID-19 Sore Throat sometimes
Cold Sore Throat common
Flu Sore Throat sometimes
Seasonal allergies Sore Throat sometimesUsually mild
Runny or stuffy nose
COVID-19 Runny or stuffy nose rare
Cold Runny or stuffy nose common
Flu Runny or stuffy nose sometimes
Seasonal allergies Runny or stuffy nose rare
Watery Eyes
COVID-19 Watery Eyes no
Cold Watery Eyes no
Flu Watery Eyes No
Seasonal allergies Watery Eyes common
Fatigue
COVID-19 Fatigue sometimes
Cold Fatigue sometimes
Flu Fatigue common
Seasonal allergies Fatigue sometimes
Headaches
COVID-19 Headaches sometimes
Cold Headaches rare
Flu Headaches common
Seasonal allergies Headaches sometimesRelated to sinus pain
Muscle/Body aches
COVID-19 muscle body aches sometimes
Cold  muscle body aches no
Flu muscle body aches common
Allergies muscle body aches no
Diarrhea
COVID-19 Diarrhea rare
Cold Diarrhea no
Flu Diarrhea sometimesFor children
Seasonal allergies Diarrhea no