For most people who get the flu, staying at home and getting rest and plenty of fluids will be enough for their bodies to fight it off. If your fever doesn't go away or your symptoms become severe, seek medical attention, says Schaffner. It doesn't matter how young and healthy you were a few days ago. Flu complications can become serious and antiviral medications or hospitalization may be needed.
Seeking immediate medical attention is especially important if you develop a headache and severe stiffness in your neck as this may be a sign of bacterial meningitis, not the flu.
Bacterial meningitis starts out with flu-like symptoms such as fever and achiness, but quickly the patient will become seriously ill, will be so stiff as to be unable to put his/her chin to the chest, and will be difficult to rouse from sleep, Schaffner says.
Bacterial meningitis can lead to brain damage, coma, and death when left untreated so any of these symptoms should not be ignored.