Skip to main content

Influenza (flu) and COVID-19 are both contagious respiratory illnesses, but they are caused by different viruses. COVID-19 is caused by infection with a coronavirus, and flu is caused by infection with an influenza virus.

COVID-19 symptoms generally appear two to 14 days after exposure to SARS-CoV-2. Flu symptoms usually appear about one to four days after exposure to an influenza virus. Both COVID-19 and flu can have varying degrees of signs and symptoms, ranging from no symptoms to severe symptoms. COVID-19 and the flu may cause similar symptoms making it difficult to differentiate based on symptoms alone. Because of the similarities, testing is imperative to confirm a diagnosis and determine the correct course of treatment. However, there are some differences.

  Symptom or sign COVID-19 Flu
Cough Usually (dry) Usually
Muscle aches Usually Usually
Tiredness Usually Usually
Sore throat Usually Usually
Runny or stuffy nose Usually Usually
Fever Usually Usually — not always
Nausea or vomiting Sometimes Sometimes (more common in children)
Diarrhea Sometimes Sometimes (more common in children)
Shortness of breath or difficulty breathing Usually Usually
New loss of taste or smell Usually (early — often without a runny or stuffy nose) Rarely

TREATMENT

Flu: Your healthcare provider might recommend the following to relieve symptoms and support your body’s natural defenses such as: taking medication, like acetaminophen or ibuprofen to reduce fever, drinking water or receiving intravenous fluids to stay hydrated, and getting plenty of rest to help the body fight the virus. Prescription influenza antiviral medications are FDA-approved to treat the flu.

COVID-19: Your healthcare provider might recommend the following to relieve symptoms and support your body’s natural defenses such as: taking medications, like acetaminophen or ibuprofen, to reduce fever, drinking water or receiving intravenous fluids to stay hydrated, and getting plenty of rest to help the body fight the virus. For patients who test positive for COVID-19, Paxlovid is the first line of recommended therapy for treatment. For more up-to-date information, please visit our COVID-19 page – https://allymedical.com/covid-19/

https://www.cdc.gov/flu/symptoms/flu-vs-covid19.htm#:~:text=Similarities%3AFor%20both%20COVID,if%20they%20had%20flu

https://www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/covid-19-cold-flu-and-allergies-differences/art-20503981