Tweet Is swine flu (H1N1) a cause of an epidemic or pandemic in 2009? An epidemic is defined as an outbreak of a contagious disease that is rapid and widespread, affecting many individuals at the same time. The swine flu outbreak in Mexico fits this definition. A pandemic is an epidemic that becomes so widespread that it affects a region, continent, or the world. As of April 2009, the H1N1 swine flu outbreak does not meet this...