Cholera may also be transmitted by shellfish harvested from nonpolluted waters since V. cholerae O1 is part of the autochthonous microbiota of these waters. Most of these cases were detected only after epidemiological investigation. Probably more sporadic cases have occurred, but have gone undiagnosed or unreported. The illness is generally self-limiting. Antibiotics such as tetracycline have been demonstrated to shorten the course of the illness.
Death occurs from dehydration and loss of essential electrolytes.
Medical treatment to prevent dehydration prevents all complications. V. cholerae serogroup O1 and O139 may be recovered from foods by methods similar to those used for recovering the organism from the feces of infected individuals. Pathogenic and non-pathogenic forms of the organism exist, so all food isolates must be tested for the production of cholera enterotoxin. Literature references can be found at the links below. Since the onset of the Vibrio cholera epidemic in Latin America in 1991, most cases of cholera in the United States have occurred among persons traveling to the United States from cholera-affected areas or who have eaten contaminated food brought or imported from these areas.