Cholera is a well-known infectious disease causing epidemics that have decimated European population in the 19th century. The death toll in cholera epidemics reached hundred thousands dead. The danger of the disease, however, decreased rapidly in developed countries, yet small and insignificant epidemics occur in Africa and southern America.
The disease is cause by bacterium known as vibrio cholerae. The infection usually occurs after ingestion of water or food contaminated by the bacteria. The bacteria get into the digestive tract and settle in mucosa of the small intestine. Lack of hygiene in the past was related to frequent contamination of public water resources followed by widespread epidemics.
Once the bacteria enter the mucosa of small intestine, they begin to proliferate and secrete a toxin (cholera toxin) that disrupts the ability to thicken the stool by absorbing water. This results in profuse watery diarrhea leading to a severe dehydration and mineral loss. The overall deterioration with fluid loss and disruption of inner environment had been usually fatal in the past.
In countries where cholera occurs, an epidemic with above mentioned classic symptoms is highly suspicious. The stool may be examined including microbiological examination and the diagnosis may be confirmed by serology from blood test (specific antibodies against the bacteria).
The best prevention is an adherence to hygienic standards and regulation, especially strict quality control of water resources purity.
The basic method of treatment is as sufficient hydration. Without it, the disease is often fatal, with proper hydration; cholera can be a relatively benign disease. Antibiotics may help a little but adequate fluid intake really is essential. Modern society in civilized countries is usually able to provide patients with adequate care during an epidemic including parenteral hydration (i.e. administration of fluid directly into the venous system). When this care is assured, the death rate of cholera is about 1%.