Flu Symptoms 2024 How Long Does It Last. More evidence points to long flu being a real phenomenon, with a large study showing symptoms persist at least 4 weeks or more after some people are. Like long covid, long flu is a real illness.

If you have symptoms of long flu, including shortness of breath and a lingering cough, and they last for more than two. The cdc recommends most adults get the annual flu shot in september or october.