Diarrhea is a symptom, not a disease. It is defined as passing frequent loose stools. The acute form lasts only a day or two and usually isn't serious, but it can be linked with some other problems. It affects people of all ages, and some types are infectious. The average person may get acute diarrhea 3 to 5 times a year, and long-term effects are rare. Children under 5 years of age experience about 1 to 3 episodes of diarrhea every year.
Chronic diarrhea lasts longer than 2 weeks, or shows up as repeated episodes of diarrhea lasting less than 2 weeks each. An inflammatory bowel condition such as ulcerative colitis or Crohn's disease may be to blame.
Children and infants with diarrhea should be seen by a doctor.