How Long Does the Flu Last?

For most healthy people, flu symptoms can appear one to four days after exposure and will last five to seven days. However, the flu will resolve itself eventually. Those who have had the flu shot will have can have symptoms that are less severe and last for a shorter amount of time.

Reference:

Harvard: https://www.health.harvard.edu/staying-healthy/how-long-does-the-flu-last#:~:text=Symptoms%20usually%20appear%20from%20one,may%20continue%20to%20feel%20fatigued.

CDC: https://www.cdc.gov/flu/about/keyfacts.htm

WHO: https://www.who.int/influenza/spotlight