Herd immunity, bile duct cancer and peripheral artery disease

This week, Dr. S. Vincent Rajkumar, a Mayo Clinic hematologist and researcher, discusses the concept of herd immunity and whether it would control the spread of COVID-19. Then, Dr. Bret Petersen, a Mayo Clinic gastroenterologist, discusses treatment for bile duct cancer. And Dr. Randall DeMartino, a Mayo Clinic vascular surgeon, explains peripheral artery disease, a common circulatory problem.