<prompt> Most common cause of travellers diarrhea is:EHECETECEPECEIEC  <response>: Ans: B ETEC Ref: Ananthanarayan, Paniker CJ. Textbook of Microbiology. 8th Edition. London: John Wiley Sons: 2009. Pg 276-7Explanation:There are 5 classes of E. coli that cause diarrheal diseases:Enterotoxigenic E. coli ETECEnteroinvasive E. coli EIECEnterohemorrhagic E. coli EHECEnteropathogenie E. coli EPECEnteroaggregative E. coli EAggEC.ETECFimbria! adhesins e.g. CFA I, CFAII, K88, K99Non invasiveProduce labile toxine LT andor Stable toxin ST toxinWatery diarrhea in travelers Travellers Diarrhea.No inflammation. No fever EIECNon fimbria l adhesins, possibly outer membrane proteinInvasive, penetrate and multiply within epithelial cellsDoes not produce shiga toxinDysentery-like diarrhea mucous, bloodSevere inflammation. FeverEPECNon fimbria adhesin intiminModerately invasive not as invasive as Shigella or EIEC.Does not produce LT or ST; some reports of shiga-like toxinUsually infantile diarrhea; watery diarrhea similar to ETECSome inflammation, no feverEAggECProduce ST-Itke toxin EAST and a hemolysinPersistent diarrhea in young children without inflammation, no feverEHECModerately invasiveProduce shiga toxinPediatric diarrhea,Copious bloody discharge hemorrhagic colitisIntense inflammatory response, may be complicated by hemolytic uremic synromeShiga Toxin-Producing Escherichia coli STECA type of enterohemorrhagic E. coli EHEC bacteriaHemolytic Uremic Syndrome 