Nasopharyngeal SARS-CoV-2 may not be dispersed by a high-flow nasal cannula

Tetsuya Suzuki, Shinichiro Morioka, Kei Yamamoto, Sho Saito, Shun Iida, Katsuji Teruya, Jin Takasaki, Masayuki Hojo, Kayoko Hayakawa, Satoshi Kutsuna, Sho Miyamoto, Seiya Ozono, Tadaki Suzuki, Eiichi N. Kodama, Norio Ohmagari

Research output: Contribution to journalArticlepeer-review


A high-flow nasal cannula (HFNC) therapy plays a significant role in providing respiratory support to critically ill patients with coronavirus disease 2019 (COVID-19); however, the dispersion of the virus owing to aerosol generation is a matter of concern. This study aimed to evaluate if HFNC disperses the virus into the air. Among patients with COVID-19 admitted to private rooms with controlled negative pressure, we enrolled those admitted within 10 days of onset and requiring oxygenation through a conventional nasal cannula or HFNC therapy. Of the 17 patients enrolled, we obtained 22 samples (11 in the conventional nasal cannula group and 11 in the HFNC group). Viral RNA was detected in 20 nasopharyngeal swabs, and viable viruses were isolated from three nasopharyngeal swabs. Neither viral RNA nor viable virus was detected in the air sample at 0.5 m regardless of the oxygen-supplementation device. We detected viral RNA in two samples in the conventional nasal cannula group but not in the HFNC therapy group in gelatin filters located 3 m from the patient and the surface of the ventilation. This study directly demonstrated that despite viral RNA detection in the nasopharynx, viruses may not be dispersed by HFNC therapy. This warrants further research to determine if similar results can be obtained under different conditions.

Original languageEnglish
Article number2669
JournalScientific reports
Issue number1
Publication statusPublished - 2023 Dec

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Nasopharyngeal SARS-CoV-2 may not be dispersed by a high-flow nasal cannula'. Together they form a unique fingerprint.

Cite this