1 Department of Microbiology, Schools of Dentistry and Medicine, University of California Medical Center
The rate and sequence in which various body areas of the newborn infant acquire coagulase-positive staphylococci was studied in two hospitals at a time when nursery infections were not occurring. The infants became colonized rapidly on numerous body surfaces in one nursery, and more slowly and less extensively in the other. Skin and rectal cultures usually became positive before those from the nose, throat, and eye. The groin and axilla of infants in one nursery tended to become colonized before the umbilical cord; in the other nursery, colonization of the umbilical cord often preceded that of the groin or the axilla. Different body sites of an individual infant often became colonized with different strains of staphylococci, as determined by phage typing, and two strains sometimes were detected in a single site.
The carrier state of the newborn infant can be assessed accurately only by culturing many body sites and by phage typing many colonies. Cultures of skin, rectum, and umbilical cord are likely to be more informative than nasal cultures, because the nose is often the last site to become colonized. The culture procedure which is most likely to portray the carrier state may have to be determined independently for each hospital nursery to be studied.
It may be difficult to prevent acquisition of hospital strains by applying bacteriostatic substances to the umbilical cord stump or portions of the skin because of the extent to which staphylococci multiply upon the skin, mucous membranes, and perhaps within the intestinal tract.
Submitted on May 26, 1959