SARS-CoV-2 in the Air Surrounding Patients during Nebulizer Therapy

Jostein Gohli; Arne Broch Brantsæter; Kari Oline Bøifot; Carola Grub; Beathe Kiland Granerud; Jan Cato Holter; Anne Margarita Dyrhol Riise; Madelen Foss Smedholen; Marius Dybwad

doi:10.1155/2022/9297974

SARS-CoV-2 in the Air Surrounding Patients during Nebulizer Therapy

Can J Infect Dis Med Microbiol. 2022 Sep 17:2022:9297974. doi: 10.1155/2022/9297974. eCollection 2022.

Authors

Jostein Gohli¹, Arne Broch Brantsæter^{2

3}, Kari Oline Bøifot^{1

4}, Carola Grub⁵, Beathe Kiland Granerud^{6

7

8}, Jan Cato Holter^{6

8}, Anne Margarita Dyrhol Riise^{2

8}, Madelen Foss Smedholen⁹, Marius Dybwad^{1

4}

Affiliations

¹ Norwegian Defence Research Establishment, P. O. Box 25, No. 2027 Kjeller, Oslo, Norway.
² Department of Infectious Diseases, Oslo University Hospital, P. O. Box 4956, Nydalen, No. 0424, Oslo, Norway.
³ Norwegian National Unit for CBRNE Medicine, Oslo University Hospital, P. O. Box 4956, Nydalen, No. 0424, Oslo, Norway.
⁴ Department of Analytics, Environmental & Forensic Sciences, King's College London, 150 Stamford Street, London SE1 9NH, UK.
⁵ Institute of Microbiology, Norwegian Armed Forces Joint Medical Services, P. O. Box 25, No. 2027, Kjeller, Oslo, Norway.
⁶ Department of Microbiology, Oslo University Hospital, P. O. Box 4950, Blindern, No. 0424, Oslo, Norway.
⁷ Department of Nursing, Health and Laboratory Science, University College of Østfold, P. O. Box 700, No. 1757, Halden, Oslo, Norway.
⁸ Institute of Clinical Medicine, University of Oslo, P. O. Box 1171, Blindern, No. 0318, Oslo, Norway.
⁹ Oslo University Hospital, P. O. Box 4950, Nydalen, No. 0424, Oslo, Norway.

Abstract

Nebulizer therapy is commonly used for patients with obstructive pulmonary disease or acute pulmonary infections with signs of obstruction. It is considered a "potential aerosol-generating procedure," and the risk of disease transmission to health care workers is uncertain. The aim of this pilot study was to assess whether nebulizer therapy in hospitalized COVID-19 patients is associated with increased dispersion of SARS-CoV-2. Air samples collected prior to and during nebulizer therapy were analyzed by RT-PCR and cell culture. Total aerosol particle concentrations were also quantified. Of 13 patients, seven had quantifiable virus in oropharynx samples, and only two had RT-PCR positive air samples. For both these patients, air samples collected during nebulizer therapy had higher SARS-CoV-2 RNA concentrations compared to control air samples. Also, for particle sizes 0.3-5 µm, particle concentrations were significantly higher during nebulizer therapy than in controls. We were unable to cultivate virus from any of the RT-PCR positive air samples, and it is therefore unknown if the detected virus were replication-competent; however, the significant increase in smaller particles, which can remain airborne for extended periods of time, and increased viral RNA concentrations during treatment may indicate that nebulizer therapy is associated with increased risk of SARS-CoV-2 transmission.