The flu affects millions of Americans each year, causing missed days at work or school, hospitalizations, and in some cases, even death. Despite the ubiquity of the flu each year, it’s still easy to confuse some of the symptoms with other illnesses.
Influenza is caused by a highly contagious virus that enters the body through the mouth or nose. There are several subtypes and strains of the flu, and some strains are known for causing more severe symptoms than others.
References
Centers for Disease Control and Prevention. (2024). Cold versus flu.
Centers for Disease Control and Prevention. (2024). Signs and symptoms of flu.
MedlinePlus. (2022). Flu.
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Written by:
Lauren Smith, MALauren Smith, MA, has worked in health journalism since 2017. Before joining GoodRx, she was the senior health editor and writer for HealthiNation.
Reviewed by:
Brian Clista, MDDr. Clista is a board-certified pediatrician who works in private practice in Pittsburgh, Pennsylvania. He previously served as a National Health Service Corporation Scholar in the inner city of Pittsburgh for 11 years.
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