Changes

}}</ref> Although ''E. coli'' is one of the most common bacteria on the surface of human [[skin]], strains found in hospitals tend to be particularly virulent. ''E. coli'' that live in the intestinal tract cause urinary tract infections when allowed to get into the sterile urinary tract. Whether intact or circumcised, baby boys sitting in poopy diapers allows ''E. coli'' an opportunity to enter the urinary tract. And, of course, fiddling with the [[foreskin ]] and introducing bacteria foreign to the baby's body or his urinary tract can also cause UTI, too. The tight [[foreskin]] of the infant boy acts as a sphincter to allow [[urine]] to flow out, but prevents contaminants and pathogens from coming in.<ref name="Fleiss 1998">{{FleissP HodgesF VanHoweRS 1998}}</ref>