The National Institute on Aging (NIA) awarded a $572,333 Project Grant under the Aging Research Federal Grant Program (CFDA 93.866) to the University of Alabama to investigate the mechanisms underlying aged host-virus interactions. The project aims to (1) determine how modulation of the host's metabolism in older individuals aids in survival of viral infection, and (2) examine how the aged organism's physiological environment impacts the evolution of RNA virus pathogenicity. The research will utilize the Drosophila melanogaster model organism to explore infection tolerance mechanisms and the build-up of defective viral species in older versus younger hosts. Two sub-awards were provided to Florida International University to conduct viral genome sequencing and to the University of Alabama at Birmingham to study the role of mitochondrial dysfunction in metabolic complications of obesity and aging. This research is expected to provide important insights into virus-host interactions in the aged population and potentially lead to therapeutic improvements for infected elderly patients and the prevention of novel viral strain emergence.