Vibrio Cholerae Infection

Vibrio cholerae infection is caused by a gram-negative, motile bacterium commonly found in aquatic environments, leading to cholera—a severe diarrheal disease characterized by profuse watery diarrhea due to the action of cholera toxin. Transmission occurs primarily via the fecal-oral route in regions with inadequate sanitation and clean water access. Virulent strains harbor the CTXφ bacteriophage encoding the cholera toxin, which binds to GM1 gangliosides on intestinal epithelial cells, triggering massive fluid and electrolyte secretion into the intestinal lumen. The bacterium exhibits a complex life cycle involving culturable forms and viable but non-culturable (VBNC) states, with environmental factors influencing its transition between these phases. It persists in nature through biofilm formation and chitin utilization, while outer membrane vesicles aid in resisting host defenses. Only 5–10% of infected individuals develop severe symptoms, though annual estimates suggest 1.3–4.0 million cases and 21,000–143,000 deaths, predominantly in South Asia, Africa, and Latin America. Treatment relies on rehydration, antibiotics, and zinc in children, with an oral vaccine approved by the FDA in 2016. Non-cholera Vibrio species such as V. vulnificus and V. parahaemolyticus cause vibriosis, typically through consumption of raw seafood, resulting in milder gastrointestinal illness and contributing to over 80,000 cases annually in the United States alone.