Patient description: A 34 year old man comes to the clinic complaining of dizziness and severe diarrhea since yesterday. He has returned from an international trip few days ago and was living in a camp in Sudan for a month. He developed abdominal pain followed by bloating and nausea as well as loose bowel movements. Soon he was having profuse watery diarrhea without odor. The stool is watery and white but the patient has no fever. Blood pressure is 95/62 lying down and drops to 75/40 standing. The skin turgor has reduced. HR is 110 and he looks ill with dry mucosa. V. cholerae was seen in dark-field microscopy of a fresh stool specimen. The lab study is as bellow: Sodium 137 meq/L Potassium 2 meq/L Chloride 94meq/L CO2 15 meq/L Fecal leukocytes None seen Fecal occult blood Negative

Clinical trial eligibility criteria: eligible ages (years): 18.0-45.0,  Escherichia Coli Infections Male or female age 18-45, inclusive Healthy as judged by the Principal Investigator (PI) and determined by medical history, physical examination, vital signs, screening laboratories, and medication history Capable of understanding, consenting and complying with the entire study protocol including the inpatient period Female subjects must be of non-childbearing potential, or if of childbearing potential (as determined by the investigator) must be practicing abstinence or using an effective licensed method of birth control (e.g., oral contraceptives; diaphragm or condom in combination with contraceptive jelly, cream, or foam; intrauterine contraceptive device, or Depo-Provera; skin patch; vaginal ring or cervical cap) for 30 days prior to vaccination and must agree to continue such precautions during the study and for 30 days after the Day 28 study visit Male subjects must agree not to father a child during the study and for 90 days after the Day 0 study visit Provide voluntary written informed consent and attained at least 70% on an examination about the study on the first attempt Have normal screening laboratories for serum glutamic pyruvic transaminase (SGPT) alanine aminotransferase (ALT), creatinine, sodium, potassium, total white blood count (WBC), hemoglobin, neutrophils, lymphocytes, platelets, urine protein, urine glucose and urine red blood cells (RBC)  Women who are pregnant or lactating or have a positive serum pregnancy test at screening or upon admission to inpatient facility Subjects who are immunocompromised or immunodeficient, or have had a prior malignancy (exception: a history of basal cell or squamous cell carcinoma in remission without treatment for more than 5 years prior to study entry) History of clinically significant chronic illness or other condition requiring chronic medication therapy History of malabsorption or maldigestion disorder (e.g., celiac sprue), major gastrointestinal (GI) surgery, or any other chronic GI disorders that would interfere with the study or the investigational product Any current or past use of immunosuppressive medications including inhaled steroids (e.g., for asthma) within 6 months of screening Recent (e.g., within 5 years) history of travel to a cholera or Enterotoxigenic Escherichia coli (ETEC) endemic area, raised in a cholera or ETEC endemic area or a history of raising a child from an endemic area for cholera or ETEC. Individuals who may work with Vibrio (V) cholerae or ETEC in the laboratory are also excluded Vaccination against or infection with cholera or E. coli, or participation in a clinical trial using cholera or ETEC vaccine or organisms at any time History of drug or alcohol abuse any time in the last 6 months Presence of HIV antibody, hepatitis C antibody, or positive hepatitis B surface antigen Clinically abnormal screening electrocardiogram (ECG) defined as pathologic Q waves and significant ST-T wave changes; for left ventricular hypertrophy; and any non-sinus rhythm excluding isolated premature atrial contractions