| Popis: |
It is seen that Enterotoxigenic E.coli (ETEC) are a major cause of diarrheal disease in humans and animals. ETEC-mediated diarrhea in humans is largely endemic and is responsible for one-fifth of all severe diarrheal illnesses. In animals, ETEC infections are generally associated with neonatal diarrhea in calves, lambs, and pigs, and postweaning diarrhea in pigs. These infections cause significant morbidity and mortality in these animals with substantial economic impact on the livestock industry. ETEC are distinguished from other E.coli pathotypes by their production of enterotoxins LT (heat-labile enterotoxin) and ST (heat-stable enterotoxin). It is seen that for an E.coli pathogen to be considered an ETEC strain, it must produce at least one of these enterotoxins. Another characteristic common to ETEC strains is their ability to adhere to the intestinal epithelium, a phenotype mediated by structures referred to as colonization factors. Colonization factor mediated adherence allows for the delivery of enterotoxins and the subsequent host secretory response that is experienced as diarrhea. |
