EFFECT OF PREVENTIVE ADMINISTRATION OF A NONPATHOGENIC ESCHERICHIA-COLI STRAIN ON THE COLONIZATION OF THE INTESTINE WITH MICROBIAL PATHOGENS IN NEWBORN-INFANTS

In a randomized, double-blind study, 27 healthy newborn infants were c olonized with the nonpathogenic Escherichia coli strain Nissle 1917 (E . coli DSM 6601, Mutaflor (R)) during the first 5 days of life by dail y oral inoculation of 1 ml of a suspension with 10(8) living cells. A second group of 27 newborns, used as controls, received a placebo susp ension (1 ml of phosphate-buffered saline) instead. Stool samples were taken on days 1, 2, 3, 5, and 21, and 6 months after birth. All sampl es were examined for the presence of the nonpathogenic E. coli strain and of pathogenic and potentially pathogenic microorganisms. The admin istered E. coli strain was detected in the stools of the colonized new borns from day 2 and remained present throughout the study in more tha n 90% of these infants. Colonization with true and potential bacterial pathogens was significantly reduced in infants receiving E. coli stra in Nissle 1917 compared to the placebo group - both with respect to nu mbers of pathogens and to the spectrum of species.