Background: Methicillin Resistant Staphylococcus aureus (MRSA) is a hardy and extremely virulent multidrug resistant organism that has been a major cause of hospital acquired infections ever since its discovery in the 1960’s. It has severe consequences such as causing increased hospital length of stay, economic burden, morbidity, and mortality. MRSA prevention strategies have been advocated by national and international organizations which have been successful in reducing the burden of healthcare-associated MRSA. However, MRSA has been increasing in the community settings and this is an alarming and poorly understood rend because these infections occur in populations that have no known risk factors. In order to develop successful control strategies for this emerging threat. In order to develop successful control strategies for this emerging threat, it is important to understand the epidemiology, risk factors and links associated with community associated MRSA so that new and novel prevention strategies, using existing resources and cutting edge technology, can be developed.
Methods: A cross sectional observational study design was used. The aims were accomplished by leveraging and utilizing the existing infrastructure of the OSUMC Information Warehouse, the Ohio State Health Network, and the OSUMC Microbiology Laboratory. Specific aim 1 was to develop an infection control collaborative and an innovative cross institutional platform, using existing information technology resources and infrastructure, for use as an electronic health information exchange between multiple hospitals spread across a large geographic area. Specific aim 2 was to estimate the proportion of community associated MRSA cases among all MRSA cases in rural community hospitals, and to identify the risk factors associated with community associated MRSA. Logistic regression was used to examine risk factors for community MRSA strain. Lastly, specific aim 3 was to identify patterns of intra-facility and inter-facility transmission of MRSA by evaluating epidemiological and geographic links via use of geographic information systems and social network analysis.
Results: An infection control collaborative among the Ohio State University Medical Center and 7 rural outreach hospitals was formed with the successful development and deployment of a health information exchange for MRSA. Over a 1 year time period from March 2009 – March 2010, 1024 MRSA isolates were collected, 625 from the OSUMC and 399 from the 7 outreach hospitals. The proportion of community associated MRSA in rural hospitals was 85%, while it was only 26% at the OSUMC (p-value < 0.001). A risk factor analysis found that age was a significant (p-value = <0.001) predictor of community associated MRSA (OR 0.92, 95% CI 0.90 – 0.94; p< 0.001). Rep-PCR testing found 75 distinct clusters. All clusters were examined for potential patterns of intra and/or inter-facility transmission. Two rep-PCR patters, 29 and 101, provide vivid illustrations of potential transmission links.
Conclusions: Using surveillance to understand the transmission of MRSA is critical in infection prevention and control activities. Using health information technology is necessary to safely, effectively and efficiently treat patients and prevent outbreaks. By utilizing and enhancing existing resources, protocols, and information technology infrastructure health information exchanges can be developed. Novel methods including SNA and GIS should be further explored to provide an in-depth understanding of the transmission patterns of MRSA within and between facilities, regional geographical variations, and national trends. This increased understanding can then be used to plan and implement effective prevention programs that respond to local and regional trends.