Acute infectious syndrome of the stomach lining and intestines. Symptoms include diarrhea, vomiting, and abdominal cramps. Severity varies from transient diarrhea to life-threatening dehydration, children and the very old being more at risk for the latter. Many microorganisms produce it, either by secreting toxins or by invading the gut walls. Forms of gastroenteritis include food poisoning, cholera, and traveler's diarrhea. Depending on cause and severity, treatment includes antibiotics or simply supportive care.

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