Scott E. Hensley, Ph.D., Wistar Institute (IMAGE) The Wistar Institute Caption Scott E. Hensley, Ph.D., and other researchers from the Wistar Institute led a study that identified a new viral mutation responsible for middle-aged adults being more susceptible to influenza during the 2013-2014 flu season. Credit The Wistar Institute Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.