Probiotic strains detect and suppress cholera in mice.

Microbiota-modulating interventions are an emerging strategy to promote gastrointestinal homeostasis. Yet, their use in the detection, prevention, and treatment of acute infections remains underexplored. We report the basis of a probiotic-based strategy to promote colonization resistance and point-of-need diagnosis of cholera, an acute diarrheal disease caused by the pathogen Oral administration of , a common dietary fermentative bacterium, reduced intestinal burden and improved survival in infected infant mice through the production of lactic acid. Furthermore, we engineered an strain that specifically detects quorum-sensing signals of in the gut and triggers expression of an enzymatic reporter that is readily detected in fecal samples. We postulate that preventive dietary interventions with fermented foods containing natural and engineered strains may hinder cholera progression and improve disease surveillance in populations at risk of cholera outbreaks.