The first case of bird-to-human transmission of the avian influenza has been identified, the U.S. Centers for Disease Control and Prevention says. Doctors say a 40-year-old Colorado man tested positive for the virus. However, a group of experts are skeptical as to whether the case was a true bird-to-human transmission. In this week’s episode, I speak with Dr. Shaun Grannis, vice president of data and analytics at the Regenstrief Institute, for an explanation.