On April 13, 2009 (Calendar March 18, 2009), the A1N1 influenza (swine flu) epidemic spread worldwide. Swine influenza on April 13, 2009 the A1N1 influenza epidemic began to spread worldwide. A1N1 influenza is an acute respiratory infectious disease, the pathogen of which is a new A1N1 influenza virus that spreads among the population. Unlike previous or current seasonal influenza viruses, the strain of the virus contains genetic segments of swine influenza, avian influenza and human influenza three influenza viruses. People are generally susceptible to A1N1 influenza, and can infect people, and the early symptoms of human influenza after flu are similar to common influenza, including fever, cough, throat, physical pain, headache, cold and