Influenza is often called a respiratory disease, but it affects the whole body. The victim usually becomes acutely ill with fever, chills, weakness, loss of appetite and aching of the head, back, arms and legs. The influenza sufferer may also have a sore throat and a dry cough, nausea, and burning eyes. The patient is often left exhausted for days afterwards. For healthy children and adults, influenza is typically a moderately severe illness.
Most people are back on their feet within a week.
For people who are not healthy or well to begin with, influenza can be very severe and even fatal. The symptoms described above have a greater impact on these persons. In addition, complications can occur. Most of these complications are bacterial infections because the body can be so weakened by influenza that its defenses against bacteria are low. Bacterial pneumonia is the most common serious complication of influenza.