Pathogens and Their Effects
BACTERIA  
E. coli Gastroenteritis
Salmonella typhi Typhoid fever
Other salmonella species Various typhoid-like fevers, gastroenteritis, septicemia (generalized infections in which organisms multiply in the bloodstream)
Shigella dysenteriae and other species Bacterial dysentery
Vibrio cholera Cholera
VIRUSES  
Rotavirus Gastroenteritis
Norwalkvirus Gastroenteritis
Poliovirus Poliomyelitis
Coxsackievirus (some strains) Various, including severe respiratory diseases, fevers, rashes, paralysis, aseptic meningitis, myocarditis
Echovirus Various, similar to coxsackievirus (evidence is not definite except in animal experiments)
Adenovirus Respiratory and gastrointestinal infections
Hepatitis Infectious hepatitis; also may affect kidneys and spleen
PROTOZOA
Cryptosporidium Gastroenteritis
Giardia lambia Diarrhea
Entamoeba histolytica Amoebic dysentery
Isospora belli and Isospora hominus Intestinal parasites, gastrointestinal infection
Balantidium coli Dysentery, intestinal ulcers