Reduction of colonization of Enterotoxigenic Escherichia Coli (ETEC) in mice by Probiotic (Lactobacillus casei

Diarrhea still is one of the major health problems in many parts of the world. In developing countries Enterotoxigenic Escherichia coli (ETEC) is a major cause of severe disease in children and it is the most frequent cause of traveler’s diarrhea. Diarrhea caused by ETEC is dependent on its colonization in the small intestine, thus reducing its colonization can potentially reduce the disease. Probiotics are microorganisms (bacteria and yeasts) that have beneficial effects on the health of the host when ingested. The purpose of this study was to use the Lactobacillus casei as a probiotic organism for reducing the shedding and colonization of ETEC in the Balb/c mouse intestine. The mice allocated into either a probiotic-treated group or a control group. The treated group were given probiotic (1×108cfu) for either 3 or 6 days, and the control group were not given any probiotic. Seventy-two hours after the last oral administration of probiotic, the test and control mice were challenged with ETEC (1×108cfu). Frequency of shedding was evaluated by colony counting of fecal samples. The results indicated that mice given probiotic for 3 or 6 days had a significant reduction in the frequency of ETEC shedding (p<0.001) compared to the control group. The findings suggests the Lactobacillus casei as a possible candidate for a probiotic against Enterotoxigenic Escherichia coli.