Staphylococcus aureus at a maternity ward. I. Colonization of mothers and neonates and survival of various S. aureus types in colonized individuals.

Colonization by Staphylococcus aureus, characterized by phage type or production of enterotoxins and toxic-shock-syndrome-toxin, was followed in 50 mothers and their babies. Types or groups of staphylococci predominating during the particular period at the maternity department were evaluated according to survival rates in the colonized subjects. S. aureus frequently colonized nipples at the start of lactation and was found regularly on umbilical stump and in eye and mouth corners of the babies. During the second stage of the study phage untypable staphylococci producing enterotoxin C (NT/C) strongly predominated. These microorganisms colonized in the greatest extent both mothers and neonates. The majority of NT/C complex originated probably from one or two clones characterized, among others, by high biological activity.