The World Health Organization increased its pandemic alert level to 5 this week, one step short of declaring a full pandemic. In the US as of Thursday, over 100 confirmed cases of the flu had been reported in 12 states, including one US death. However, the Centers for Disease Control and Prevention said that "the more recent illnesses and the reported death suggest that a pattern of more severe illness associated with this virus may be emerging in the U.S. Most people will not have immunity to this new virus and, as it continues to spread, more cases, more hospitalizations and more deaths are expected in the coming days and weeks."
In this hour, we'll get the latest on the outbreak of Type A, H1N1 influenza. What are researchers learning from studying the virus -- and how are doctors and other health professionals dealing with its spread? What is there to be learned from studying historic pandemics?
Produced by Christopher Intagliata, Senior Producer