original article Respiratory Syncytial Virus Infection Control Challenges with a Novel Polymerase Chain Reaction Assay in a Tertiary Medical Center Parham Sendi, MD, FIDSA; 1,2 Adrian Egli, MD, PhD; 3,4 Marc Dangel, MPH; 1 Reno Frei, MD; 1 Sarah Tschudin-Sutter, MD; 1,5 Andreas F. Widmer, MD, FIDSA, FSHEA 1 objectives. To evaluate host characteristics, mode of infection acquisition, and infection control procedures in patients with a positive respiratory syncytial virus (RSV) test result after the introduction of the GenXpert Influenza/RSV polymerase chain reaction (PCR) assay. design. Retrospective cohort study. patients. Adults with a positive PCR test result for RSV who were hospitalized in a tertiary academic medical center between January 2015 and December 2016 were included in this study. Our infection control policy applies contact isolation precautions only for immunocompro- mised patients. methods. Patients were identified through 2 databases, 1 consisting of patients isolated because of RSV infection and 1 with automatically collected laboratory results. Baseline and clinical characteristics were collected through a retrospective medical chart review. The rate of and clinical factors associated with healthcare-associated RSV infections were evaluated. results. In total, 108 episodes in 106 patients hospitalized with a positive Xpert RSV test result were recorded during the study period. Among them, 11 episodes were healthcare-associated infections (HAIs) and 97 were community-acquired infections (CAIs). The mean length of hospital stay (LOS, 40.2 vs 11.2 days), the mean number of room switches (3.5 vs 1.7) and ward switches (1.5 vs 0.4), and the mean numbers of contact patients (9.9 vs 3.8) were significantly longer and higher in the HAI group than in the CAI group (P < .0001). Surveillance of microbiology records and clinical data did not reveal evidence for a cluster or an epidemic during the 2-year observation period. conclusions. The introduction of a rapid molecular diagnostic test systematically applied to patients with influenza-like illness may challenge current infection control policies. In our study, patients with HAIs had a prolonged hospital stay and a high number of contact patients, and they switched rooms and wards frequently. Infect Control Hosp Epidemiol 2017;38:1291 – 1297 Respiratory syncytial virus (RSV) is a typical cause of winter- time respiratory illness 1 and is increasingly recognized in both older adults and immunocompromised patients. 2 Therefore, it may be argued that patients presenting with respiratory symptoms during the influenza season should be simulta- neously tested for influenza virus and RSV. The Xpert Flu/RSV XC assay (Cepheid, Sunnyvale, CA), which detects both influenza virus A/B and RSV, demonstrates sensitivities ran- ging from 90.6% to 97.9% and specificities from 99.4% to 100% for RSV. 3–5 The test has a short turnaround time of approximately 1.5 hours and provides semiquantitative results. During the influenza season of 2014/2015, we introduced this rapid molecular test for patient assessments presenting with an influenza-like illness to the emergency department of our university hospital. Using this strategy, we aimed to identify and isolate early patients with a transmissible viral respiratory disease requiring hospitalization. However, this strategy led to challenges from the perspectives of infection control and hospital hygiene because RSV infection might be increasingly recognized. Patients with RSV disease can trigger hospital outbreaks. 6–9 To prevent person-to-person transmission, the Centers for Disease Control and Prevention (CDC) and the Healthcare Infection Control Practices Advisory Committee recommend standard and contact precautions. 10 In our institution, we implemented a combination of droplet and contact isolation precautions for RSV (hereafter called ‘contact Affiliations: 1. Department of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, University Basel, Basel, Switzerland; 2. Institute for Infectious Diseases, University of Bern, Bern, Switzerland; 3. Division of Clinical Microbiology and Laboratory Medicine, University Hospital Basel, Basel, Switzerland; 4. Applied Microbiology Research, Department of Biomedicine, University of Basel, Switzerland; 5. Department of Clinical Research, University Hospital Basel, University Basel, Basel, Switzerland. © 2017 by The Society for Healthcare Epidemiology of America. All rights reserved. 0899-823X/2017/3811-0004. DOI: 10.1017/ice.2017.213 Received May 21, 2017; accepted September 10, 2017 infection control & hospital epidemiology november 2017, vol. 38, no. 11