Mark “Tuck” Stibich, PhD, MHS PhD, FIDSA, is an infectious disease epidemiologist, chief scientific officer and cofounder of Xenex, where he focuses his efforts on scientific research and development, new technology, and protocol design. He holds a doctoral degree from the Johns Hopkins University School of Public Health, a master’s in health science (also from Johns Hopkins), and a bachelor’s degree from Yale University. He is a fellow of the Infectious Diseases Society of America. He has conducted research around the world and published numerous scientific papers on ultraviolet light, interventions in hospital settings, and other topics. He holds more than 135 granted patents and speaks frequently on infectious disease topics.