Safety of Sublingual dmLT for ETEC

Inclusion Criteria: \- Male or female ages 18-45, inclusive. - Provide written informed consent before initiation of any study procedures. - General good health, without (a) significant medical illness, (b) clinically significant physical examination findings, including vitals, as determined by the PI, and (c) screening laboratory values outside the site's normal limits. - Within 46 days of vaccination, have normal screening laboratories, per Appendix B for white blood cells (WBCs), hemoglobin (Hgb), platelets, absolute neutrophil count (ANC), sodium, potassium, chloride, bicarbonate, blood urea nitrogen (BUN), creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST). - Have normal screening laboratories for urine protein Trace protein is acceptable. - HgbA1C \<6.5% at screening. - Demonstrate comprehension of the protocol procedures and knowledge of study by passing a written examination (passing grade is at least 70 percent). - Agrees to complete all study visits and procedures. - Female subjects must be of non-childbearing potential (as defined as surgically sterile or postmenopausal for more than 1 year), or if of childbearing potential, must be using an effective method of birth control (e.g., use hormonal or barrier birth control such as implants, injectables, combined oral contraceptives, some intrauterine devices \[IUDs\], cervical sponges, diaphragms, condoms with spermicidal agents must have a vasectomized partner) within 2 months of vaccination…