diarrhoea

Frequent or excessive action of the bowels so that the faeces are liquid or semiliquid. It is caused by intestinal irritants (including some drugs and poisons), infection with harmful organisms (as in dysentery, salmonella, or cholera), or allergies.

Diarrhoea is the biggest killer of children in the world. In 2006 the World Health Organization reported that around 2 million children die from diarrhoeal disease each year. The commonest cause of dehydrating diarrhoea is human rotavirus infection. Dehydration as a result of diarrhoeal disease can be treated by giving a solution of salt and glucose by mouth in large quantities (to restore the electrolyte balance in the blood). Since most diarrhoea is viral in origin, antibiotics are ineffective.