Becker's Clinical Quality & Infection Control

16 INFECTION CONTROL & PATIENT SAFETY 5 things to know about how flu spreads in the US By Megan Knowles R esearchers at the University of Chi- cago created models to predict how flu spreads across the U.S. each year, using geographic movements, demographics and social interactions, according to a study published in eLife. To create the models, the researchers used several large datasets, which listed healthcare visits, geographic movements and demo- graphics for more than 150 million people over the course of nine years. e study authors examined healthcare records from Truven MarketScan, a database that holds de-identified patient data from over 40 million U.S. families. ey then analyzed the 2003-11 flu seasons, marking the insurance claims that indicated patients received treatment for flu-like symptoms. Here are five things to know about the study. 1. e study found seasonal flu outbreaks originate in warm, humid areas in the south and southeastern parts of the country and migrate away from the coasts, moving northward. 2. Before the flu starts to migrate from U.S. coasts, the counties where flu outbreaks orig- inated tended to be near the Gulf of Mexico or the Atlantic Ocean, the study found. 3. e researchers also examined 1.7 billion geo-located messages from Twitter over a 3.5-year period to capture how people traveled between counties on a week-by- week basis. For example, if a person regularly sends tweets from home, then tweets from work or while visiting family in the next county, the study authors determined this would create a movement pattern between those two counties. 4. e study authors found people in the southern part of the country have a high degree of social connectivity. In these areas, there are a greater number of tight-knit com- munities, which can increase the population's chances of spreading the flu. 5. ese models allowed the researchers to recreate three years of historical flu data. As the first reports of the flu start coming each fall, these tools could be used as part of health officials' prevention efforts, said Andrey Rzhetsky, PhD, senior study author. "For example, if flu-like symptoms are being reported in one county, you could tell people in neighboring counties to stay away from crowds, or you could focus vaccination efforts in certain places in advance," he said. "It could be used essentially as a weather forecast for the flu." n Frequent MRSA transmission associated with patient admission to multiple hospitals By Anuja Vaidya A study published in Clinical Infectious Diseases examined methicillin-resistant Staphylococcus aureus transmission pathways between hospitals. Researchers performed a cross-sectional observational study in the United Kingdom. They identified MRSA patients at inpatient, outpatient and community settings between Nov. 1, 2011, and Feb. 29, 2012. They also identified genetically defined MRSA transmission clus- ters in individual hospitals and across the healthcare network. Of 610 MRSA patients, 248 were linked in 90 transmis- sion clusters, of which 27 spanned multiple hospitals. Analysis of a large 32-patient sequence type 22-MRSA cluster showed 81.3 percent had multiple contacts with one another during ward stays at any hospital. Thus, ward-based transmission of MRSA due to frequent pa- tient admissions to multiple hospitals is common. "Limiting in-ward transmission requires sharing of MRSA status data between hospitals," the study authors concluded. n Study: Movement in OR most influences microbial load By Anuja Vaidya A study published in the jounrnal Infection Control & Hospital Epidemiology examined the factors that affect microbial loads at various locations within the operating room. Researchers studied 27 videotaped procedures to deter- mine high-volume and low-volume areas in the OR. They placed air samplers and settle plates in representative locations during 21 procedures in four different ORs. They studied microbial load in colony-forming units during two different seasons. For each procedure, they measured the temperature and humidity, number of door openings, phys- ical movement and the number of people in the OR. The researchers found microbial load correlated with the physical movement of people in an area with the number of door openings; and the number of people in that area. Additionally, the time of year the samples were taken affect- ed microbial load. "Establishing operational guidelines or developing OR layouts that focus on minimizing movement by incorpo- rating desirable internal storage points and workstations can potentially reduce microbial load, thereby potentially reducing surgical site infection risk," study authors con- cluded. n

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