Est. time: 19 min
Novel H1N1 (referred to as "swine flu" early on) is a new influenza virus causing illness in people. This new virus was first detected in people in the United States in April 2009. This virus is spreading from person-to-person worldwide, probably in much the same way that regular seasonal influenza viruses spread. On June 11, 2009, the World Health Organization (WHO) signaled that a pandemic of novel H1N1 flu was underway. This tutorial provides a general overview of the swine flu. The content comes from the Centers for Disease Control and Prevention.