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