Gastroenteritis Health Article

Definition

Gastroenteritis is a general term for infection or irritation of the digestive tract, particularly the stomach and intestine. It is frequently referred to as stomach or intestinal flu, although the influenza virus does not cause this illness. Major symptoms include nausea, vomiting, diarrhea, and abdominal cramps. Fever and overall weakness sometimes accompany these symptoms. Gastroenteritis typically lasts about three days. Adults usually recover without problem, but children, the elderly, and persons with an underlying disease are more vulnerable to complications such as dehydration.

Description

Gastroenteritis is an uncomfortable and inconvenient ailment, but it is rarely life-threatening in the United States and other developed nations. However, in the United States an estimated 220,000 children younger than age five are hospitalized annually with gastroenteritis symptoms. Of these children, 300 die as a result of severe diarrhea and dehydration. In developing nations, diarrhea-related illnesses are a major source of mortality. In 1990, approximately three million deaths occurred worldwide as a result of diarrheal illness.

Viral gastroenteritis

Gastroenteritis is usually caused by infection with one of these viruses: rotavirus, adenovirus, astrovirus, calicivirus, and small round-structured viruses (SRSVs). These viruses are found all over the world and are particularly problematic where sanitation is poor. Typical exposure to these viruses occurs through the fecal-to-oral route, by ingesting food that is contaminated with fecal material or by coming in contact with an infected person's vomit or diarrhea and then inadvertently bringing the contaminant to the mouth. Other routes of transmission are quite likely, because exposure to as few as 100 virus particles can cause an infection.

Typically, children are more vulnerable to rotaviruses—the most common cause of acute watery diarrhea. It is estimated that each year rotaviruses cause 800,000 deaths worldwide in children younger than age five. For this reason, much research has gone into developing a vaccine to protect children from this virus. Adults can be infected with rotaviruses, but these infections typically have minimal or no symptoms.

Adenoviruses and astroviruses are minor causes of childhood gastroenteritis, and children may become infected with caliciviruses and SRSVs. Adults experience illness from astroviruses as well, but the major causes of adult viral gastroenteritis are the caliciviruses and SRSVs. The SRSVs are a type of calicivirus and include the Norwalk, Southhampton, and Lonsdale viruses. SRSVs are the most likely to produce vomiting as a major symptom.