Protect Yourself Learn about E. coli infections and how they can be prevented. Escherichia coli (abbreviated as E. coli) are bacteria found in the environment, foods, and intestines of people and animals. E. coli are a large and diverse group of bacteria.Although most strains of E. coli are harmless, others can make you sick.scherichia coli (abbreviated as E. coli) are bacteria found in the environment, foods, and intestines of people and animals.