Scientists Discover Viral 'Enigma Machine' (IMAGE) University of Leeds Caption A code hidden in the arrangement of the genetic information of single-stranded RNA viruses tells the virus how to pack itself within its outer shell of proteins. Credit University of Leeds 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.