Each year, there are over 1 billion cases of diarrhea in infants and children (see Diarrhea in Children). Fortunately, most of these cases improve on their own. But infant diarrhea can be very serious or even deadly in some situations (that is why replacing fluids and electrolytes is so important).
There are many possible causes of diarrhea in infants. These include such things as infections (with bacteria, a virus, or parasite), certain medical conditions, food intolerance, or food allergy.
(Click Diarrhea Causes for more information about possible causes of diarrhea.)
One common cause of diarrhea in infants is the stomach flu (known medically as viral gastroenteritis). Many different viruses can cause stomach flu in infants. The most common types include:
Infection with the rotavirus is the most common cause of acute diarrhea in infants. In the United States, rotavirus is responsible for approximately 5 to 10 percent of all cases of diarrhea among children under five years of age. However, because rotavirus causes more severe diarrhea than other bugs, it accounts for a greater proportion of severe diarrhea cases (for example, 40 to 50 percent of diarrhea hospitalizations).
Rotavirus accounts for more than 500,000 physician visits and approximately 55,000 to 70,000 hospitalizations each year among children under five years of age. An estimated 1 in 200,000 children with rotavirus diarrhea die from the complications of the infection.