Paralytic Polio is a devastating cause of flaccid paralysis and its eradication is a major initiative of the World Health Organization (WHO). The addition of a mucosal adjuvant to intradermal (ID) IPV formulations may arrest fecal shedding and halt perpetuation of an environmental reservoir of the disease. We will evaluate the mucosal and cell mediated immune effects of a novel mucosal adjuvant: Enterotoxigenic Escherichia coli (ETEC), double-mutant heat labile toxin (dmLT). In addition, we will investigate the role of the gastrointestinal microbiota in modulating OPV-induced PV infection and replication capacity. In year 1, clinical samples immediately available from a completed pilot trail evaluating the safety and immunogenicity of dmLT-fIPV (CHRMS# 19-0048) will be utilized to develop methods and initiate immunologic investigations. During this time, regulatory and administrative work will be finalized to support the initiation of a second clinical trail in year 2.