Becker's Clinical Quality & Infection Control

13 INFECTION CONTROL Occupying C. diff-Contaminated Hospital Areas Significantly Increases Infection Risk By Anuja Vaidya W hen a patient is in a hospital area previously occupied by someone with a Clostridium difficile in- fection, that patient is much more likely to develop a C. diff infection, according to a study presented at Hospital Medicine 2017. Hospital Medicine 2017 is the annual meet- ing of the Society of Hospital Medicine in Las Vegas. Researchers developed a methodology using EHR data to map potential C. diff transmis- sion. ey analyzed patient encounters in a health system from 2013 through 2015, which included 86,648 hospitalizations. During the hospitalizations, there were 434,745 patient location changes. e researchers classified a patient as "ex- posed to C. diff" if they occupied a space in the hospital that had been occupied by a pa- tient with C. diff in prior 24 hours. Research- ers followed both exposed and unexposed patients for 60 days. Additionally, researchers calculated the odds ratio for developing C. diff if exposed in comparison to unexposed individuals who passed through the same contaminated location. e study shows that exposure to C. diff in the emergency department was significantly associated with the development of the infec- tion within the next 60 days. Also, researchers found that getting a CT scan in the ED within 24 hours aer a patient with C. diff had used the scanner was associated with increased odds of developing an infection in comparison to a patient getting a CT scan when the machine was not contaminated. "Our novel data analytic strategy may be widely applicable for infection control quality improvement at other institutions and for other infectious diseases," study authors note. n Researchers Tracked Germs From Day 1 at a New Hospital — Here's What They Found By Heather Punke B y the time the University of Chicago's Center for Care and Discovery opened in February 2013, researchers had already been swabbing the hospital for two months, with the aim of learning how germs spread through a hospital's environment. "The Hospital Microbiome Project is the single biggest microbiome analysis of a hospital performed, and one of the largest microbiome studies ever," Jack Gilbert, PhD, told Science Life, a publication of The University of Chicago Medicine & Biological Sciences. Dr. Gilbert led the research and authored a study published May 24 in Science Translational Medicine. The study started two months prior to the hospital open- ing its doors to patients on Feb. 23, 2013, and continued for 10 months after. Researchers swabbed 10 patient care rooms and two nursing stations daily, as well as the patients in those rooms and the nurses caring for them. They found the following: 1. Human germs dominate quickly. Before the hos- pital opened, bacteria like Acinetobacter and Pseudo- monas were common. However, human-related germs like Corynebacterium, Staphylococcus and Streptococ- cus soon took over after the hospital opened. "As soon as [the hospital] was populated with patients, doctors and nurses, the bacteria from their skin took over," Dr. Gilbert said in Science Life. 2. Patients bring in infection-causing germs. According to coverage in Science, 20 of the 252 patients in the study suffered a hospital-acquired infection during their stay. But when researchers swabbed their rooms and the cli- nicians who cared for them, they failed to find the germs responsible for the infection. "The most likely explanation is the patients already had those bacteria when they were admitted," Dr. Gilbert told Science. 3. Patients quickly contribute to the room's microbi- ome. When patients first occupy a room, they tend to pick up germs from the surrounding area. But within the first 24 hours, the transmission route reverses and "the patient's microbiome takes over the hospital space," Dr. Gilbert told Science Life. 4. Surfaces are more likely to harbor drug-resistant germs than patients' skin. "[G]enes conferring antimi- crobial resistance were consistently more abundant on room surfaces than on the skin of the patients inhabiting those rooms," the study authors wrote. 5. Staff were more likely to pass germs to patients than vice versa. "[A]nalysis suggested that hospital staff were more likely to be a source of bacteria on the skin of patients than the reverse," the study concludes. 6. Longer hospital stays could promote antibiotic resistance. Per Science Life, "Samples from the rooms of 92 patients who had longer hospital stays, measured in months, revealed a trend. Some potentially harmful bacteria, such as Staphylococcus aureus and Staphylococ- cus epidermidis, faced with continual selective pressure, managed to acquire genes that could boost antibiotic resistance and promote host infection." 7. Weather affects germ spread. When the weather is warmer and more humid, staff members passed more bacteria among each other, the researchers found. n

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