Escherichia coli, also known as E. coli is a bacterium naturally present in the digestive tract of humans and many animals. It is normally non-pathogenic, meaning not responsible for infection, but may become dangerous when subject to certain conditions. In most cases, some strains lead to intestinal disorders like diarrhea, but E. Coli can also spread to other organs, including the urinary tract in women, causing most cases of cystitis by the spread of stool bacteria issued from the anus to the perineum and genitals. Escherichia coli is usually very sensitive to antibiotics that cure the infection without relapse. More rarely, generalized infections or meningitis are also possible.