Screening for Staphylococcus aureus carriage in pregnancy: usefulness of novel sampling and culture strategies

OBJECTIVE: The purpose of this study was to determine the most sensitive strategy for the detection of Staphylococcus aureus among pregnant women and newborn infants. STUDY DESIGN: We obtained cultures for S aureus from 5 body sites of women at 35-37 weeks' gestation. We obtained cultures from their newborn infants before hospital discharge. RESULTS: Of 209 women who were screened, 29% of the women had at least 1 culture that was positive for S aureus; 5% of infants were S aureus carriers. The sensitivities of each site for S aureus detection were 52% nares, 50% throat, 13% rectum, 8% vagina, and 10% skin. The most sensitive combination of 2 sites was nares and throat (88%). Perinatal transmission of S aureus occurred in 4 women. Maternal methicillin-resistant S aureus carriage rate was 1%. Two infants carried the USA300 methicillin-resistant S aureus. CONCLUSION: Screening single body sites is insensitive for the detection of S aureus carriage in pregnancy. Sampling nares and throat is essential to the identification of S aureus carriers.