Viral gastroenteritis symptoms may appear 1-3 days after you are infected and can range from mild to severe. Symptoms usually
last just a day or two, but occasionally they may persist as
long as 10 days. Because the symptoms are similar, it is easy to confuse diarrhea caused by viruses with diarrhea caused by bacteria (e.g., Clostridium difficile, salmonella, and E. coli) or parasites (e.g., giardia). If your symptoms persist, see your doctor for further workup and management.