what bacteria causes diarrhea in humans
Parasites such as Giardia lamblia and cryptosporidium can cause diarrhea. Common bacterial causes of diarrhea include campylobacter, salmonella, shigella and Escherichia coli. Diarrhea caused by bacteria and parasites can be common when traveling in developing countries and is often called traveler's diarrhea.1  Medications. 2  Many medications can cause diarrhea. 3  The most common are antibiotics. Many medications can cause diarrhea. 2  The most common are antibiotics. 3  Antibiotics destroy both good and bad bacteria, which can disturb the natural balance of bacteria in your intestines. 4  This disturbance sometimes leads to an infection with bacteria called Clostridium difficile, which also can cause diarrhea.