Bacteriophage-based probiotic preparation for managing Shigella infections

Diarrhea remains a major public health challenge worldwide, and it also may significantly hamper US troop operations during combat and peacekeeping missions overseas. Antibiotics can be used to treat diarrheal diseases; however, some foodborne and waterborne bacterial pathogens are developing resistance against antibiotics, which limits their effectiveness. Also, antibiotics – because of their broad spectrum activity – may disturb/alter the GI tract’s normal and beneficial microflora, which may create additional health problems. Therefore, novel approaches are needed to help prevent and treat bacterial-elicited diarrhea among US troops, thereby improving their combat readiness and performance. Synbiotics (combinations of probiotics and prebiotics) may provide one such approach. However, one potentially useful probiotic intervention that has not received much attention in the past is to use bacteriophages to target “problem” bacterial species in the human GI tract. Bacteriophages are viruses that infect bacteria, are highly specific, and lyse their targeted bacteria, including antibiotic-resistant strains. Thus, synbiotic preparations containing (i) bacteriophages targeting specific diarrhea-causing bacteria, (ii) previously described, bacteria-based probiotics, and (iii) prebiotics may provide excellent protection against diarrheal illnesses among US troops and civilian populations. In this application, we propose to begin developing and testing a synbiotic preparation whose phage component is specifically active against Shigella spp., which are significant diarrhea-causing pathogens.