The World Health Organization (WHO) has updated its fact sheet on diarrhoeal diseases.
Diarrhoea is defined as the passage of three or more loose or liquid stools per day (or more frequent passage than is normal for the individual).
Frequent passing of formed stools is not diarrhoea, nor is the passing of loose, “pasty” stools by breastfed babies.
Diarrhoea is usually a symptom of an infection in the intestinal tract, which can be caused by a variety of bacterial, viral and parasitic organisms.
Infection is spread through contaminated food or drinking-water, or from person-to-person as a result of poor hygiene.
There are three clinical types of diarrhoea:
- acute watery diarrhoea – lasts several hours or days, and includes cholera;
- acute bloody diarrhoea – also called dysentery; and
- persistent diarrhoea – lasts 14 days or longer.
Diarrhoeal disease is the second leading cause of death in children under five years old. It is both preventable and treatable.
Each year diarrhoea kills around 525 000 children under five.
A significant proportion of diarrhoeal disease can be prevented through safe drinking-water and adequate sanitation and hygiene.
Globally, there are nearly 1.7 billion cases of childhood diarrhoeal disease every year.
In low-income countries, children under three years old experience on average three episodes of diarrhoea every year. Each episode deprives the child of the nutrition necessary for growth. As a result, diarrhoea is a major cause of malnutrition, and malnourished children are more likely to fall ill from diarrhoea.
Diarrhoea is a leading cause of malnutrition in children under five years old.
The most severe threat posed by diarrhoea is dehydration.
During a diarrhoeal episode, water and electrolytes (sodium, chloride, potassium and bicarbonate) are lost through liquid stools, vomit, sweat, urine and breathing. Dehydration occurs when these losses are not replaced.
The degree of dehydration is rated on a scale of three.
- Severe dehydration (at least two of the following signs)
- sunken eyes
- unable to drink or drink poorly
- skin pinch goes back very slowly ( ≥2 seconds )
- Some dehydration (two or more of the following signs):
- restlessness, irritability
- sunken eyes
- drinks eagerly, thirsty
- No dehydration (not enough signs to classify as some or severe dehydration)
- Infection- Rotavirus and E.coli are the commonest pathogens in low-middle income countries
- Malnutrition- underlying malnutrition increases susceptibility of children to diarrhoea
- Contaminated water source- contaminated by human or animal faeces.
- Others- poor personal hygiene, unhygienic food, unsafe domestic water storage, fish and seafood from polluted water
Prevention and Treatment:
Key measures to prevent diarrhoea include:
- access to safe drinking-water;
- use of improved sanitation;
- hand washing with soap;
- exclusive breastfeeding for the first six months of life;
- good personal and food hygiene;
- health education about how infections spread; and
- rotavirus vaccination.
Key measures to treat diarrhoea include the following:
- Rehydration: with oral rehydration salts (ORS) solution. ORS is a mixture of clean water, salt and sugar. It costs a few cents per treatment. ORS is absorbed in the small intestine and replaces the water and electrolytes lost in the faeces.
- Zinc supplements: zinc supplements reduce the duration of a diarrhoea episode by 25% and are associated with a 30% reduction in stool volume.
- Rehydration: with intravenous fluids in case of severe dehydration or shock.
- Nutrient-rich foods: the vicious circle of malnutrition and diarrhoea can be broken by continuing to give nutrient-rich foods – including breast milk – during an episode, and by giving a nutritious diet – including exclusive breastfeeding for the first six months of life – to children when they are well.
- Consulting a health professional , in particular for management of persistent diarrhoea or when there is blood in stool or if there are signs of dehydration.
Link to the updated fact sheet:
Link to WHO page on water-related disease:
Link to WHO’s Integrated Action Plan for Pneumonia and Diarrhoea: