Viral causes of diarrhea

Viral diarrhea is a common disease of children and adults. It can occur as a sporadic-endemic event or in special settings, such as epidemics, traveler's diarrhea, or diarrhea in the immunocompromised host. Acute sporadic diarrhea of childhood is one of the most significant health problems worldwide. Its severest and commonest cause is rotavirus, but calicivirus, adenovirus, astrovirus, and rotovirus are also important causes. The most important viral causes of sporadic, endemic acute diarrhea in adults are probably the caliciviruses or the less common serotypes of viruses that cause sporadic diarrhea in childhood. Caliciviruses are the major cause of epidemic viral diarrhea in families, institutions, ships, and as foodborne or waterborne illnesses. Acute viral diarrhea also is seen in travelers. The pathogenesis of acute viral diarrhea is not understood completely. In rotavirus infection, the epithelial cell is an active participant in mobilizing the host response. Viral antigens may directly stimulate secretion or promote the synthesis of host mediators of inflammation or secretion. Cytomegalovirus and Epstein-Barr virus cause diarrhea in immunocompromised patients.