Describe influenza with its symptoms and prevention

Describe influenza with its symptoms and prevention.
Influenza or flu is an acute respiratory tract infection caused by influenza virus. It is of three types A, B and C. Influenza virus A and B have caused epidemics throughout the world. Influenza virus C occurs sporadically in the form of small outbreak. Major reservoirs of influenza virus are animals and wild birds. Influenza is spread mainly from person to person by droplet infection created by sneezing, coughing or talking and enters the respiratory tract. Its incubation period is 18 to 72 hours.
Symptoms: Fever, chills, aches and pain, coughing and weakness.
Prevention: Sufferers should cover their faces with handkerchief while coughing and sneezing. Healthy persons should remain away from such patients.