Airborne Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Hospitals: Effects of Aerosol-Generating Procedures, HEPA-Filtration Units, Patient Viral Load, and Physical Distance.
Clin Infect Dis
; 75(1): e89-e96, 2022 08 24.
Article
in English
| MEDLINE | ID: covidwho-1868254
ABSTRACT
BACKGROUND:
Transmission of coronavirus disease 2019 (COVID-19) can occur through inhalation of fine droplets or aerosols containing infectious virus. The objective of this study was to identify situations, patient characteristics, environmental parameters, and aerosol-generating procedures (AGPs) associated with airborne severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus.METHODS:
Air samples were collected near hospitalized COVID-19 patients and analyzed by RT-qPCR. Results were related to distance to the patient, most recent patient diagnostic PCR cycle threshold (Ct) value, room ventilation, and ongoing potential AGPs.RESULTS:
In total, 310 air samples were collected; of these, 26 (8%) were positive for SARS-CoV-2. Of the 231 samples from patient rooms, 22 (10%) were positive for SARS-CoV-2. Positive air samples were associated with a low patient Ct value (OR, 5.0 for Ct <25 vs >25; Pâ =â .01; 95% CI 1.18-29.5) and a shorter physical distance to the patient (OR, 2.0 for every meter closer to the patient; Pâ =â .05; 95% CI 1.0-3.8). A mobile HEPA-filtration unit in the room decreased the proportion of positive samples (OR, .3; Pâ =â .02; 95% CI .12-.98). No association was observed between SARS-CoV-2-positive air samples and mechanical ventilation, high-flow nasal cannula, nebulizer treatment, or noninvasive ventilation. An association was found with positive expiratory pressure training (Pâ <â .01) and a trend towards an association for airway manipulation, including bronchoscopies and in- and extubations.CONCLUSIONS:
Our results show that major risk factors for airborne SARS-CoV-2 include short physical distance, high patient viral load, and poor room ventilation. AGPs, as traditionally defined, seem to be of secondary importance.Keywords
Full text:
Available
Collection:
International databases
Database:
MEDLINE
Main subject:
SARS-CoV-2
/
COVID-19
Type of study:
Experimental Studies
/
Prognostic study
Limits:
Humans
Language:
English
Journal:
Clin Infect Dis
Journal subject:
Communicable Diseases
Year:
2022
Document Type:
Article
Affiliation country:
Cid
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