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Contact-Free Co-Culture Model for the Study of Innate Immune Cell Activation During Respiratory Virus Infection
Published on: February 28, 2021
Influenza virus emitted by naturally-infected hosts in a healthcare setting
Samira Mubareka1, Andrea Granados2, Ushma Naik3
1Sunnybrook Research Institute, 2075 Bayview Avenue suite B103, Toronto, ON M4N 3M1, Canada.
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.
Objectives:
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.
Design:
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.
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