Not Medical Advice: Yes, the person is contagious as long as E. coli bacteria (O157:H7) can be found in their stool. The bacteria may be passed from an infected person to another due to poor hygiene or inadequate hand washing.
As explained by WebMD, E. coli (Escherichia coli) is the name of a germ, or bacterium, that lives in the digestive tracts of humans and animals.
There are many types of E. coli, and most of them are harmless. But some can cause bloody diarrhea. Some strains of E. coli bacteria (such as a strain called O157:H7) may also cause severe anemia or kidney failure, which can lead to death.
Other strains of E. coli can cause urinary tract infections or other infections.
You get an E. coli infection by coming into contact with the feces, or stool, of humans or animals. This can happen when you drink water or eat food that has been contaminated by feces.
You can also learn more about E. coli at the Centers for Disease Control and Prevention.
Check out some tips for preventing E. coli and Salmonella infection, shared by Food Poison Journal.