What are the causes and symptoms of travelers diarrhea?
Bacterial infections are the most common cause of the illness. Viruses and occasional parasites also can be the cause. As for the bacteria involved, toxin producing types of E. coli (called enterotoxigenic) account for approximately 40–60% of cases, with Campylobacter and Shigella each reported in at least 10% of cases. In some studies, Campylobacter has accounted for almost half of the attacks, especially during cooler seasons of the year. The cause can vary depending on several factors, including the season and country visited. More than one organism can be found in 15–30% of cases, while none is identified in up to 40% of cases worldwide. Rotaviruses and a parvovirus called Norwalk agent also are responsible for TD. Giardia is probably the most common parasite identified, though amoebas (Entamoeba histolytica), Cryptosporidium, and Cyclospora are being found with increasing frequency. Amazingly, research released in 2003 found that those living in undeveloped countries with poor san
