Influenza, commonly known as “flu,” is a respiratory disorder caused by an influenza virus. It is an infectious disorder which is of three types: type A, type B, and type C. The common symptoms of the disorder are cough, cold, fever, and sore throat, which can be mild or severe. The disease is spread easily from person to person by sneezing, coughing, or touching surfaces, and is generally diagnosed on the basis of symptoms. 更多
