In my opinion, the health and safety of both mother and infant are supported when all laboring women are offered a culture for methicillin-resistant staphylococcus aureus (MRSA). Why is this culture important? This test is important because it could have major implications for the appropriate care of the newborn. Although Staphylococcus aureus is a common bacterial pathogen that frequently colonizes skin, anterior nares, or the perineum in humans, MRSA is a growing problem and has become gradually more difficult to treat due to increasing resistance (Beigi & Hanrahan, 2007). MRSA is prevalent in the community and is no longer solely a hospital-acquired infection, meaning that women in labor could be colonized and not know it. This places their newborn at risk for colonization and infection (Beigi & Hanrahan, 2007).

Many intensive care units, including neonatal intensive care units (NICUs), participate in active surveillance for MRSA, obtaining cultures on all newborns on admission and routinely during hospitalization, as does my institution. When infants admitted to the NICU are cultured to identify if they are colonized with MRSA, some of those cultures are positive, but what does this really mean for the care of this infant? Skin colonization with S. aureus can occur within 24 to 48 hours of birth from contact with the skin of adults or the environment (Bratcher, 2005). Did the infant have contact with a healthcare worker with MRSA or with a contaminated surface? Is the mother colonized with MRSA? Unless we know the culture status of the mother, we as healthcare providers have no way of understanding why a newborn's culture is positive for MRSA or how to care for these patients appropriately. Infants colonized with MRSA are placed in isolation on contact precautions and may be kept together to prevent the spread of MRSA in the unit. This topic is especially important because S. aureus is the second most common pathogen that causes late-onset sepsis in very low birthweight infants in NICUs (Bratcher, 2005). Bloodstream infections caused by S. aureus and MRSA outbreaks in NICUs can be prolonged and difficult to eradicate (Bratcher, 2005).

The existence of MRSA colonization in pregnant women has potential serious implications for newborns and may cause an increased rate of infection in both pregnant women and full-term infants and neonates in the NICU (Beigi & Hanrahan, 2007). Although most obstetrical patients are in generally good health and at low risk for infections, we do know that transmission of MRSA from mothers to infants has been documented. Evidence of maternal-infant transmission has been documented through nasal passages and genital secretions and through placental transmission, mastitis, and contaminated human milk (Bratcher, 2005). When the mother's status is known, she is able to practice appropriate handling of her infant, rigorous hand hygiene, and treatment, if needed.

Knowing whether laboring women are colonized with MRSA allows us to better care for our patients and monitor and assess our units to prevent transmission among patients. As we continue to care for patients colonized with MRSA, it is imperative for all healthcare workers to assess all patients for MRSA status due to the risk for their infants. In my opinion, all laboring women should have surveillance cultures for MRSA due to the continuing increase of MRSA within our communities. Although studies such as that by Beigi and Hanrahan (2007) report low incidence of colonization in pregnant and laboring women, they note that it is present at rates consistent within the population. Continued surveillance for MRSA is warranted among this and other "low-risk" populations due to increasing reports of prevalent strains in the community and MRSA's impact on the morbidity and mortality of newborns.

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