Transmission rates define the magnitude of seasonal influenza epidemics. Thus, interventions with the​ potential to interrupt transmission – such as ventilation, filtration, UV, and vaccination – could constrain​ outbreaks and protect broad swathes of the population. Unfortunately, our ability to adopt such​ strategies, whether as private individuals or public health departments, is hindered by major gaps in our​ understanding of the effectiveness of these strategies to block respiratory virus transmission. While​ animal models can offer important insights, to fully address this and other critical knowledge gaps,​ detailed examination of respiratory virus transmission in humans is needed. We propose to use a human​ challenge model as a well-controlled experimental system to study interventions that may protect the population at large from virus transmission.