Influenza A H1N1 is a novel influenza virus that is of swine source. Clinical manifestations of this virus vary from mild respiratory symptoms to fatal respiratory or/and cardiovascular complications. The new influenza A H1N1 pandemic was first identified in April 2009 in the United States and Mexico, and then spread globally. In September 10 2010, the World Health Organization announced that the influenza A H1N1 pandemic had moved into the post-pandemic period and is no longer considered a dangerous global disease. On the 15th of August 2010, the Ministry of Health in Saudi Arabia declared that the cases of influenza A H1N1 in 2010 have drastically declined to 874 cases with no deaths or serious complications.