Sources of viral respiratory infections in Canadian acute care hospital healthcare personnel

S Buckrell; B L Coleman; S A McNeil; K Katz; M P Muller; A Simor; M Loeb; J Powis; S P Kuster; J M Di Bella; K K L Coleman; S J Drews; P Kohler; A McGeer; Canadian Healthcare Worker Study Group

doi:10.1016/j.jhin.2020.01.009

Sources of viral respiratory infections in Canadian acute care hospital healthcare personnel

J Hosp Infect. 2020 Apr;104(4):513-521. doi: 10.1016/j.jhin.2020.01.009. Epub 2020 Jan 16.

Authors

S Buckrell¹, B L Coleman², S A McNeil³, K Katz⁴, M P Muller⁵, A Simor⁶, M Loeb⁷, J Powis⁸, S P Kuster⁹, J M Di Bella¹⁰, K K L Coleman¹¹, S J Drews¹², P Kohler¹³, A McGeer¹⁴; Canadian Healthcare Worker Study Group

Collaborators

Canadian Healthcare Worker Study Group:
T Hatchette, L Holness, J Raboud, J Langley, T Mazzulli, K Nichol, L Genesove, J Oudyk, L McCaskell, N Johnson

Affiliations

¹ Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.
² Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada; Sinai Health System, Toronto, ON, Canada. Electronic address: b.coleman@utoronto.ca.
³ Canadian Center for Vaccinology, Dalhousie University, IWK Health Centre, and Nova Scotia Health Authority, Halifax, NS, Canada.
⁴ North York General Hospital and Sunnybrook Health Sciences Centre, Toronto, ON, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.
⁵ Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Unity Health, Toronto, ON, Canada.
⁶ Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
⁷ Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
⁸ Toronto East Health Network, Department of Medicine, University of Toronto, Toronto, ON, Canada.
⁹ Division of Infectious Diseases and Hospital Epidemiology, University Hospital and University of Zurich, Zürich, Switzerland.
¹⁰ Sinai Health System, Toronto, ON, Canada.
¹¹ Sinai Health System, Toronto, ON, Canada; Parkwood Institute, London Health Sciences Centre, London, ON, Canada.
¹² Canadian Blood Services, Edmonton, AB, Canada; Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada.
¹³ Division of Infectious Diseases and Hospital Epidemiology, Cantonal Hospital, St. Gallen, Switzerland.
¹⁴ Sinai Health System, Toronto, ON, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.

Abstract

Background: Viral respiratory illnesses are common causes of outbreaks and can be fatal to some patients.

Aim: To investigate the association between laboratory-confirmed viral respiratory infections and potential sources of exposure during the previous 7 days.

Methods: In this nested case-control analysis, healthcare personnel from nine Canadian hospitals who developed acute respiratory illnesses during the winters of 2010/11-2013/14 submitted swabs that were tested for viral pathogens. Associated illness diaries and the weekly diaries of non-ill participants provided information on contact with people displaying symptoms of acute respiratory illness in the previous week. Conditional logistic regression assessed the association between cases, who were matched by study week and site with controls with no respiratory symptoms.

Findings: There were 814 laboratory-confirmed viral respiratory illnesses. The adjusted odds ratio (aOR) of a viral illness was higher for healthcare personnel reporting exposures to ill household members [7.0, 95% confidence interval (CI) 5.4-9.1], co-workers (3.4, 95% CI 2.4-4.7) or other social contacts (5.1, 95% CI 3.6-7.1). Exposures to patients with respiratory illness were not associated with infection (aOR 0.9, 95% CI 0.7-1.2); however, healthcare personnel with direct patient contact did have higher odds (aOR 1.3, 95% CI 1.1-1.6). The aORs for exposure and for direct patient contact were similar for illnesses caused by influenza.

Conclusion: Community and co-worker contacts are important sources of viral respiratory illness in healthcare personnel, while exposure to patients with recognized respiratory infections is not associated. The comparatively low risk associated with direct patient contact may reflect transmission related to asymptomatic patients or unrecognized infections.

Keywords: Adult; Exposure; Healthcare worker; Hospital; Respiratory; Transmission; Viral.

MeSH terms

Adult
Aged
Canada / epidemiology
Case-Control Studies
Cross Infection / epidemiology*
Cross Infection / virology*
Female
Health Personnel
Hospitals
Humans
Influenza, Human / epidemiology
Male
Middle Aged
Respiratory Tract Infections / epidemiology*
Respiratory Tract Infections / virology*
Risk Factors
Surveys and Questionnaires
Virus Diseases / epidemiology*
Young Adult