Final answer:
Severe, frequent 'rice water' diarrhea is indicative of cholera, caused by the bacterium Vibrio cholerae, which requires immediate medical treatment.
Step-by-step explanation:
A sudden onset of severe, frequent "rice water" diarrhea is suggestive of cholera. This condition is caused by the bacterium Vibrio cholerae which is often transmitted through contaminated food and water. Cholera can lead to severe dehydration and life-threatening complications if not treated promptly. Symptoms of cholera can include dehydration, watery diarrhea, nausea, vomiting, and abdominal cramps. It is crucial for those affected to seek medical attention immediately to receive the necessary treatment, rehydration, and antimicrobial therapy.