Influenza-like Illness

Influenza-like illness (ILI), also known as acute respiratory infection (ARI) and flu-like syndrome/symptoms, is a medical diagnosis of possible influenza or other illness causing a set of common symptoms. Here, SARI refers to Severe Acute Respiratory Infection.

Symptoms commonly include fever, shivering, chills, malaise, dry cough, loss of appetite, body aches and nausea, typically in connection with a sudden onset of illness. In most cases, the symptoms are caused by cytokines released by immune system activation. and are thus relatively non-specific.

Common causes of ILI include the common cold and influenza, which tends to be less common but more severe than the common cold. Still less common causes include side effects of many drugs and manifestations of many other diseases.