USA Heatmap of Flu (IMAGE) University of Vermont Caption A heatmap of the US states illustrating the proportion of influenza seasons between 1921 and 1951 showing evidence for "relational exchange." Over 70% of seasons across all states provide support for this powerful influence on the spread of flu, a new University of Vermont study shows. Credit Courtesy Sam Scarpino. Published in <i>Nature Physics</i>. Usage Restrictions with coverage of associated story 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.