What is 2009 H1N1 influenza?

1. What is 2009 H1N1 influenza? 2009 H1N1 influenza (also called Swine Flu) is caused by a new strain of influenza virus. It has spread too many countries. Like other flu viruses, 2009 H1N1 spreads from person to person through coughing, sneezing, and sometimes...