Diarrhea

Diarrhea is a condition in which a person passes loose or liquid stools multiple times a day. It is commonly defined as the passage of three or more loose stools daily. Diarrhea is not a disease in itself; it is a symptom arising from various illnesses or causes.

Diarrhea is distinguished into acute diarrhea (lasting several days) and chronic diarrhea (lasting more than a week). The greatest danger of diarrhea is dehydration, which results from loss of fluids and salts from the body. Young children and elderly people are particularly vulnerable.

Causes

Common causes include bacterial infections (such as Salmonella, Shigella, Vibrio cholerae, and pathogenic strains of E. coli), viruses (such as rotavirus and norovirus), and parasites (such as Giardia and Entamoeba). Other causes include certain medications (particularly antibiotics), foods that cannot be digested such as milk in people who cannot break down lactose, and chronic intestinal diseases.

Transmission

The pathogens causing diarrhea are mostly transmitted through the faecal-oral route: poor sanitation, contaminated water, inadequately cooked food, or unwashed hands. In areas with limited clean water and poor sanitation, such as refugee camps, pathogens spread rapidly.

Treatment

The foundation of treatment is replacement of lost fluids. Oral rehydration solution (ORS)—a mixture of salt, sugar, and water—is the most important measure and prevents death from dehydration. Young children are also given zinc for several days to reduce the duration and severity of symptoms. Severe cases require intravenous fluid administration. Antibiotics are not used universally; they are used only when a specific bacterial cause is identified or when certain conditions such as cholera are suspected.

Prevention

Prevention depends on access to clean water, proper sanitation, handwashing with soap, and safe food. Breastfeeding of young children reduces the risk. Rotavirus vaccination reduces severe diarrhea in young children. Cholera vaccination is used in areas of high risk.