Chapter 20.3, Problem 1CSC

Unwelcome Dinner Guests

Many of the bacteria responsive for foodborne illnesses do their damage by producing toxins. For example, different populations of the bacterial species Escherichia coli may differ genetically and some genetic differences can transform this normally harmless inhabitant of the human digestive system into a toxin- producing pathogen. If one of these toxic strains, such as the ones designated 0157:H7 and 0104:H4. finds its way into a human digestive system, the bacteria attach firmly to the wall of the intestine and begin to release a toxin called shiga. Shiga toxin causes intestinal bleeding that results in painful cramping and bloody diarrhea. The toxin can damage other organs as well; victims of 0157:H7 and 0104:H4 often develop hemolytic uremic syndrome, a dangerous condition characterized by kidney failure and loss of red blood cells.

Bacteria are responsible for most foodborne illnesses. But besides bacteria, which other infectious agents can wreak havoc on the human body?