Name the causal organism of diarrhoea. Write the symptoms of it. How will you prepare oral rehydration solution?

The causative agents of diarrhoea are mainly bacteria (such as Escherichia coli and Salmonella) but some viruses (rotavirus, enterovirus) or protozoan (Entamoeba histolytica) also cause the disease.
Its symptoms are:
(i) Frequent loose motions and vomiting, which lead to dehydration.
(ii) Dehydration (loss of water from body tissues) makes patient dangerously ill in very short time.
The oral rehydration solution is simple and inexpensive solution. It can be prepared by adding sugar and small amount of salt in water. It can rapidly rehydrate the patient.