An Old Virus Fighting a New Battle (IMAGE) Duke University Medical Center Caption A modified polio vaccine has shown success in clinical trials at killing cancer cells and destroying tumors. Scientist have learned more details in how this virus engages the bodies' own immune system to attack. Credit Duke Health 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.