#  Understanding Pandemic Risk: Influenza 101 

 



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In this two-part series on influenza, step-by-step visuals are used to build the information cognitively, one piece at a time.

In the first of two videos, we learn that two strains of influenza, influenza A and B, are of concern to humans. Professor Sue J. Goldie reviews the structure of influenza A, explains two important surface proteins, and the mechanism of infection. We learn that small mutations in those surface proteins, referred to as antigenic drift, are why we need new vaccines each year for seasonal flu.



 

In the second of two videos, we continue the conversation about influenza A but focus on pandemic potential rather than its role in the seasonal flu. We distinguish epidemic versus pandemic. We discuss the zoonotic origin of influenza A and three types of “antigenic shift” which can result in a novel virus for which humans lack immunity. We discuss the criteria necessary for pandemic, namely, “spark” (i.e., novel strain enters the human population) and “spread” (i.e., transmission between humans).