PT - JOURNAL ARTICLE AU - Kanji, Jamil N. AU - Chan, Y.L. Elaine AU - Boychuk, Lesia R. AU - Boyington, Curtiss AU - Turay, Sebora AU - Kobelsky, Melissa AU - Doroshuk, Carolyn AU - Choo, Philana AU - Jacka, Susan AU - Roberts, Erin AU - Leighton, Karen AU - Smith, Stephanie W. AU - Sikora, Christopher AU - Black, Robert TI - SARS-CoV-2 outbreak in a Canadian suburban tertiary hospital necessitating full facility closure: a descriptive observational study AID - 10.9778/cmajo.20210064 DP - 2022 Jan 01 TA - CMAJ Open PG - E137--E145 VI - 10 IP - 1 4099 - http://www.cmajopen.ca/content/10/1/E137.short 4100 - http://www.cmajopen.ca/content/10/1/E137.full SO - CMAJ2022 Jan 01; 10 AB - Background: SARS-CoV-2 can cause outbreaks in community- and hospital-based settings. The aim of this study was to provide a detailed epidemiologic account of a hospital-wide SARS-CoV-2 outbreak and provide a description of case evaluations, transmission networks and the interventions implemented to stem the outbreak.Methods: We conducted a retrospective descriptive study of a hospital-wide SARS-CoV-2 outbreak at the Misericordia Community Hospital (Edmonton) from June 21 to Aug. 14, 2020. We reviewed hospital chart, public health and occupational health records to determine demographics, case type (community- or hospital-acquired), need for critical care and outcome for each case linked to the outbreak (patients, hospital staff, and community and patient visitors). We developed detailed transmission networks using epidemiologic data to determine what variables may have contributed to transmission.Results: Fifty-eight cases of SARS-CoV-2 infection were linked to this hospital outbreak (31 patients, 25 staff members and 2 visitors; 66% female, age range 19–97 years). One patient required critical care, and 11 deaths were recorded (all among inpatients). Most cases were hospital-acquired (91%), and 28% were asymptomatic at the time of diagnosis. The outbreak was composed of 2 clusters driven by protective equipment breaches, premature removal of precautions, transmission in small staff quarters and infection of a staff member after exposure to a wandering patient with dementia and asymptomatic, undetected SARS-CoV-2 infection.Interpretation: A detailed epidemiologic review of this hospital-wide outbreak shows that a SARS-CoV-2 outbreak can involve complex transmission chains and clusters. Multipronged bundled approaches, aggressive contact tracing, and patient and staff prevalence screening are important to help bring such outbreaks under control, along with ongoing vigilance in detecting delayed cases.