Natural history of neonatal colonization with group B streptococci

Thirteen percent of the newborns in our study group were colonized with group B streptococci on day 3. This colonization rate appeared constant during the first two weeks of life and then decreased to 5%. Of the babies colonized on day 3, 59% and 91% were culture-negative on days 14 and 42, respectively. Sixty-five percent of the babies carrying group B streptococci on day 14 acquired this microorganism following discharge (day 3). Babies colonized with staphylococci or Escherichia coli were found to have decreased probability of colonization with group B streptococci.