Research Activities, November-December 2013
Links found between nursing homes and hospitals in spread of MRSA
Patient Safety and Quality
Individual hospitals or hospital systems may not consider the role of patients who transfer in and out of the hospital from nursing homes when planning their infection control strategies. That may be a mistake, suggests a new study. It found that the presence of nursing homes substantially increased the effects of a hospital outbreak of methicillin-resistant Staphylococcus aureus (MRSA). This led to a relative average increase of 46.2 percent above and beyond the impact of infection when only hospitals were considered in outbreak estimates in Orange County, CA.
A MRSA outbreak in the largest nursing home had effects on many Orange County hospitals. It boosted MRSA prevalence in directly connected hospitals by an average of 0.3 percent and in hospitals not directly connected through patient transfers by an average of 0.1 percent after 6 months. The researchers used a model to simulate MRSA outbreaks among all hospitals and nursing homes in Orange County.
For their study, the researchers used different experimental scenarios simulating sustained and 6-month MRSA outbreaks in selected hospitals and nursing homes based on an absolute increase in MRSA prevalence of 10 percent in hospitals and 20 percent in nursing homes. They found that, despite their much smaller size and less frequent turnover compared to hospitals, nursing homes had a substantial impact on MRSA outbreaks that could extend for many miles. This may be due in part to the relatively high prevalence of MRSA in nursing homes, averaging 25 percent in Orange County, note the researchers. They recommend that hospitals include nursing homes in their infection control measures. There may be a benefit in applying the same rigor in infection control seen in many hospitals to nursing homes. This study was funded by AHRQ (Contract No. 290-05-0033).
See "The importance of nursing homes in the spread of methicillin-resistant Staphylococcus aureus (MRSA) among hospitals," by Bruce Y. Lee, M.D., Sarah M. Bartsch, M.P.H., Kim F. Wong, Ph.D., and others in the March 2013 Medical Care 51(3), pp. 205-215.