title: Influenza virus emitted by naturally-infected hosts in a healthcare setting.
abstract: BACKGROUND
  The emergence of novel respiratory viruses such as avian influenza A(H7N9) virus and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) highlights the importance of understanding determinants of transmission to healthcare workers (HCWs) and the public.
  
  
  OBJECTIVE
  We aim to determine the viral content of the air emitted by symptomatic inpatients or long-term care residents with laboratory-confirmed influenza virus infection (emitters), and in the breathing zones of healthcare workers who attend to them.
  
  
  METHODS
  A prospective pilot study of patients with laboratory-confirmed influenza virus infection was undertaken. Air within 1m of the patient was sampled using a high volume air sampler. In addition, a lower volume air sampler was placed <1 m from the patient, with another >1 m from the patient. Viral RNA was recovered from the samplers and submitted for quantitative real time PCR. In addition, personal button samplers were provided to HCWs.
  
  
  RESULTS
  The air emitted by 15 participants with laboratory-confirmed influenza virus infection was sampled. Of the patients infected with influenza A, viral RNA was recovered from the air emitted by 9/12 patients using the low-volume sampler; no viral RNA was detected from air emitted by patients with influenza B (n=3). Influenza virus RNA was recovered from one HCW's sampler.
  
  
  CONCLUSIONS
  Patients with respiratory virus infection emit virus into the air which disperses to >1 m and may reach the breathing zone of a HCW. This pilot study highlights the feasibility and importance of conducting a larger-scale study to identify determinants of exposure and transmission from patient to HCW.
authors.affiliation: Sunnybrook Research Institute, 2075 Bayview Avenue suite B103, Toronto, ON M4N 3M1, Canada. Electronic address: samira.mubareka@sunnybrook.ca.
authors.forename: Samira
authors.initials: S
authors.lastname: Mubareka
authors.affiliation: Public Health Ontario, 661 University Avenue, Suite 1701, Toronto, ON M5G 1M1, Canada. Electronic address: andrea.granados@mail.utoronto.ca.
authors.forename: Andrea
authors.initials: A
authors.lastname: Granados
authors.affiliation: Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M1, Canada. Electronic address: ushmanaik8@yahoo.com.
authors.forename: Ushma
authors.initials: U
authors.lastname: Naik
authors.affiliation: Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M1, Canada. Electronic address: ilyse.darwish@utoronto.ca.
authors.forename: Ilyse
authors.initials: I
authors.lastname: Darwish
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada. Electronic address: todd.cutts@phac-aspc.gc.ca.
authors.forename: Todd A
authors.initials: TA
authors.lastname: Cutts
authors.affiliation: School of Population and Public Health, University of British Columbia, Rm 366C 2206 East Mall, Vancouver, BC V6T 1Z3, Canada. Electronic address: george.astrakianakis@ubc.ca.
authors.forename: George
authors.initials: G
authors.lastname: Astrakianakis
authors.affiliation: Public Health Ontario, 661 University Avenue, Suite 1701, Toronto, ON M5G 1M1, Canada. Electronic address: jonathan.gubbay@oahpp.ca.
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Gubbay
authors.affiliation: Public Health Ontario, 661 University Avenue, Suite 1701, Toronto, ON M5G 1M1, Canada. Electronic address: adriana.peci@oahpp.ca.
authors.forename: Adriana
authors.initials: A
authors.lastname: Peci
authors.affiliation: Division of Occupational and Environmental Health, Dalla Lana School of Public Health, University of Toronto, 223 College Street, Toronto, ON M5T 1R4, Canada. Electronic address: james.scott@utoronto.ca.
authors.forename: James A
authors.initials: JA
authors.lastname: Scott
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000391:Air Microbiology; D003153:Community Health Services; D005260:Female; D006801:Humans; D009980:Influenza A virus / Q000302:isolation & purification*; D009981:Influenza B virus / Q000302:isolation & purification*; D007251:Influenza, Human / Q000635:transmission* / Q000821:virology; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects
keywords: Bioaerosol; Exposure; Healthcare; Influenza virus; Transmission