what is the most common cause of diarrhea in the u.s.
Viruses (e.g., adenovirus, astrovirus, rotavirus, Norwalk virus) are the most common cause of diarrhea in the United States. The most common ones in children are rotavirus and in adults are norovirus. Escherichia coli, Clostridium difficile, and Campylobacter, Salmonella, and Shigella spp. are common bacterial causes.