The purpose of this study was to observe the natural progression of untreated syphilis in rural African-American men in Alabama under the guise of receiving free health care from the United States government.
1 Diarrhea is caused by increased secretion of fluid into the intestine, reduced absorption of fluid from the intestine or rapid passage of stool through the intestine.  Symptoms associated with diarrhea include abdominal pain, especially cramping. Other symptoms depend on the cause of the diarrhea.
Viral gastroenteritis. Viral gastroenteritis (viral infection of the stomach and the small intestine) is the most common cause of acute diarrhea worldwide. Symptoms of viral gastroenteritis typically last only 48-72 hours and include: 1  nausea, 2  vomiting, 3  abdominal cramps, and. 4  diarrhea.