Flu Symptoms 2025 Adults Today. People who have flu often feel some or all of these signs and symptoms: A sudden onset of fever over 38°c (100.4°f);
So far this season, the cdc estimates, there have been at least 5.3 million flu illnesses, 63,000 hospitalizations, and 2,700 deaths — including at least 11 children. Flu symptoms usually come on suddenly.