Coronavirus: The difference between asymptomatic and pre-symptomatic

We're taking a closer look at the reports of people with COVID-19 but are asymptomatic. How likely these patients are to pass the coronavirus on to someone else and what people can do to protect themselves? Farshad Fani Marvasti, MD, MPH (Dr. Shad) with the Univ. of Arizona College of Medicine has the details.