Environmental Contamination by SARS-CoV-2 During Noninvasive Ventilation in COVID-19

Abstract

Background: Environmental contamination by SARS-CoV-2 from patients with COVID-19 undergoing noninvasive ventilation (NIV) in the ICU is still under investigation. This study set out to investigate the presence of SARS-CoV-2 on surfaces near subjects receiving NIV in the ICU under controlled conditions (ie, use of dual-limb circuits, filters, adequate room ventilation).

Methods: This was a single-center, prospective, observational study in the ICU of a tertiary teaching hospital. Four surface sampling areas, at increasing distance from subject's face, were identified; and each one was sampled at fixed intervals: 6, 12, and 24 h. The presence of SARS-CoV-2 was detected with real-time reverse transcriptase-polymerase-chain-reaction (RT-PCR) test on environmental swabs; the RT-PCR assay targeted the SARS-CoV-2 virus nucleocapsid N1 and N2 genes and the human RNase P gene as internal control.

Results: In a total of 256 collected samples, none were positive for SARS-CoV-2 genetic material, whereas 21 samples (8.2%) tested positive for RNase P, thus demonstrating the presence of genetic material unrelated to SARS-CoV-2.

Conclusions: Our data show that application of NIV in an appropriate environment and with correct precautions leads to no sign of surface environmental contamination. Accordingly, our data support the idea that use of NIV in the ICU is safe both for health care workers and for other patients.

Keywords: COVID-19; aerosol-generating procedures; critical care; infection control; noninvasive ventilation; patient safety.

Fig. 1.

Layout of the COVID-19 dedicated unit. Personal protective equipment (PPE) area indicates areas dedicated to doffing and donning of PPE for health care workers. PC indicates workstations for health care workers. Details of patient bed stations and positions of sampling locations are also shown.