Cholera is an acute infectious disease that is characterized by massive loss of body fluids and electrolytes through severe diarrhea. It is almost impossible to distinguish a patient with cholera from another pathogen that causes acute watery diarrhea without testing a stool sample. The etiological agent of cholera has been identified as Vibrio cholerea, a gram negative bacterium that is divided into several serogroups on the basis of O antigens. The subgroups O1 and O139 are of special interest because both can cause epidemic and pandemic cholera. It is critical to determine as quickly as possible the presence of V. cholerae O1 and O139 in clinical specimens, water, and food so that appropriate monitoring and effective preventive measures can be undertaken by public health authorities.