3/13/2016 Vibrio cholerae How cholera affects the body characteristics of the disease Initial symptoms:Loss of appetite, abdominal pain,simple diarrhea Progressive symptoms:rice water stools due to mucus Dose:1011 CFU ml of saline required to cause diarrhea in healthy volunteers 2 Dose:106 CFU gram of food required to cause diarrhea in healthy volunteers Food acts as a buffer Vibrio cholerae ADPR virulence mechanisms OFF GDP Gsa (permanently ON) Infection with V cholerae O1/0139 begins with ingestion of contaminated continued activation food or water Aof adenylate cyclase Colonization of the intestines follows cholera toxin (with help from activator) Cholera toxin is produced Severe diarrhea occurs with excessive decreased Nat absorption by villus cells [cAMP] loss of water and electrolytes increased Cr secretion by crypt cells DRAMATIC WATER LOSS through lumen of gut 93/13/2016 9 Vibrio cholerae characteristics of the disease • Initial symptoms: Loss of appetite, abd i l i i l di h bdominal pain, simple diarrhea • Progressive symptoms: rice water stools due to mucus • Dose: 1011 CFU / ml of saline required to cause di h i h lth l t diarrhea in healthy volunteers • Dose: 106 CFU / gram of food required to cause diarrhea in healthy volunteers • Food acts as a buffer Vibrio cholerae virulence mechanisms • Infection with V. cholerae O1 / O139 begins with ingestion of contaminated food or water • Colonization of the intestines follows • Cholera toxin is produced • Severe diarrhea occurs with excessive loss of water and electrolytes