Staphylococcus aureusand MRSA Colonization Rates among Gravidas Admitted to Labor and Delivery: A Pilot Study

Abstract

Objective. To determine colonization rates of Staphylococcus aureus given the potential for future intervention trials aimed at reducing surgical-site infectious morbidity, and to estimate methicillin-resistant Staphylococcus aureus (MRSA) rates in our patient population. Study design. Prospective pilot investigation comprising data from 104 gravidas admitted to an urban labor and delivery unit. All underwent anterior nares culture collection with a subset also undergoing vaginal culture collection. Results. Twenty-two percent of women were colonized in the anterior nares. Of the 28 women who had vaginal cultures collected, 4/28 (14.2%) demonstrated Staphylococcus aureus colonization. There was 82% concordance between the nares and vagina. Nine percent of isolates were MRSA strains. Overall, 2/96 (2.1%) of women were MRSA-colonized. Conclusions. Rates of Staphylococcus aureus colonization among gravidas entering labor and delivery are modest and consistent with the general population. MRSA rates among gravidas appear to be reassuringly low in this pilot study.

Community-Associated Methicillin-ResistantStaphylococcus aureus: Epidemiology and Clinical Consequences of an Emerging Epidemic

“…A study in Cleveland, OH, demonstrated a 2.1% prevalence of nasal or vaginal colonization with MRSA among 96 women admitted to a labor and delivery unit; one woman had MRSA colonization at both sites. There was no association between neonatal infection and maternal colonization with S. aureus (54).…”

Trends in Methicillin-Resistant Staphylococcus aureus Anovaginal Colonization in Pregnant Women in 2005 versus 2009

“…S. aureus has been reported to colonize the vagina in 4 to 22% of pregnant women (2,4,9,13,14). In 2005, following an outbreak of USA300 in postpartum women at our medical center (Columbia University Medical Center), we determined that the prevalence of methicillinsusceptible S. aureus (MSSA) anovaginal colonization was 16.6% and the prevalence of MRSA colonization was 0.5% (9).…”

Efficacy of Skin and Nasal Povidone-Iodine Preparation against Mupirocin-Resistant Methicillin-Resistant Staphylococcus aureus and S. aureus within the Anterior Nares

“…Postprep samples were taken via swabbing the nares at 1 h, 6 h, and 12 h. Baseline samples were taken prior to the application of prep or saline. The mean baseline level of S. aureus in subjects included in this study was log 10 formulations or mupirocin ointment (2%) for 5 min at room temperature (RT), followed by 15-min incubation at 37°C. Explants were then washed with sterile PBS containing 2% mucin.…”

“…aureus colonizes the anterior nares, skin, and mucosal surfaces of approximately 30% of the population (8)(9)(10). Nasal colonization with S. aureus is a well-known risk factor for acquisition of SSIs (11)(12)(13).…”