Project Summary/Abstract ? Clinical and Biostatistics Core The Clinical and Biostatistics Core (CBC) is a central component of the Evaluating Modes of Influenza Transmission (EMIT-2) program. The overall objective of this core is to perform a series of randomized clinical studies of influenza transmission to comprehensively evaluate viral, host, physical, and environmental factors that facilitate efficient human-to-human influenza transmission. In these studies, healthy participants who have no or very low levels of hemagglutination inhibiting antibodies to the current year?s vaccine strains will spend up to four days in contact with participants naturally infected with influenza virus and recruited by Research Project 1 (RP1). Each study in the series will employ an environmental intervention and a personal protection intervention designed by Research Project 2 (RP2). The core will provide the platform for collection of clinical and environmental samples by each of the two projects and the Advanced Bioaerosol Technology Core (ABTC). The clinical research facility for this project, Pharmaron Baltimore, has a long history of collaboration with the University of Maryland Center for Vaccine Development and is a site for the NIAID CIVIC program. The goals of this core will be achieved through the following specific aims: (1) Provide regulatory and safety infrastructure for a randomized controlled trial of influenza transmission; (2) Screen for healthy adult volunteers (Recipients), willing to temporarily reside on an inpatient containment unit approximately 2 weeks during the influenza season, and index cases with acute influenza infection (Donors); and (3) Expose un-infected eligible volunteers to influenza-infected index case patients. An independent Data and Safety Monitoring Board will be assembled to provide safety oversight over the conduct of the transmission studies. Ultimate oversight of the CBC?s activity will be the responsibility of the Core Leader (Dr. Chen) and Co-Investigator (Dr. Ortiz) and will include close coordination with the Projects and Cores of this U19.