Historically, cholera was an endemic disease in the delta area around the mouth of the Ganges River in India. This disease is encountered widely in tropical and subtropical zones. Although most of the patients within Japan are those who have returned from overseas countries, cases of infection within Japan occur.
The cholera vibrios include those that produce cholera toxin, which causes diarrhea, and those that do not. The cholera vibrios producing toxin are handled as infectious diseases, and have two serotypes: O1 and O13 (Bengal cholera vibrio).
Path of infection:
The cholera vibrios producing cholera enterotoxin are discharged in patients’ feces and vomit. They enter human bodies through the mouth (oral infection) via ingesting drinking water and food contaminated by contact with infected excrement.
The incubation period is several hours to five days (one day or so in normal cases) and the main symptom is severe watery diarrhea without pain. Those who have had their stomachs removed in operations and those who have basic diseases should be cautious as the symptom may become severe.