Detection of SARS-CoV-2 in exhaled air using non-invasive embedded strips in masks

Emily N Gallichotte; William Windsor; Stuart Watts; Nicole Sexton; Chuck Henry; Thomas Jaenisch; Molly M Lamb; Geoffrey Winstanley; Brian Adams; May Chu; Gregory D Ebel

doi:10.1016/j.ajic.2022.01.010

Detection of SARS-CoV-2 in exhaled air using non-invasive embedded strips in masks

Am J Infect Control. 2022 Aug;50(8):890-897. doi: 10.1016/j.ajic.2022.01.010.

Authors

Affiliations

¹ Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO.
² Center for Global Health, Colorado School of Public Health, Aurora, CO.
³ Department of Chemical and Biological Engineering, Colorado State University, Fort Collins, CO.
⁴ Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO. Electronic address: gregory.ebel@colostate.edu.

Abstract

Background: SARS-CoV-2 emerged in 2019 and resulted in a pandemic causing millions of infections worldwide. Gold-standard for SARS-CoV-2 detection uses quantitative RT-qPCR on respiratory secretions to detect viral RNA (vRNA). Acquiring these samples is invasive, can be painful for those with xerostomia and other health conditions, and sample quality can vary greatly. Frequently only symptomatic individuals are tested even though asymptomatic individuals can have comparable viral loads and efficiently transmit virus.

Methods: We utilized a non-invasive approach to detect SARS-CoV-2 in individuals, using polyvinyl alcohol (PVA) strips embedded in KN95 masks. PVA strips were tested for SARS-CoV-2 vRNA via qRT-PCR and infectious virus.

Results: We show efficient recovery of vRNA and infectious virus from virus-spiked PVA with detection limits comparable to nasal swab samples. In infected individuals, we detect both human and SARS-CoV-2 RNA on PVA strips, however, these levels are not correlated with length of time mask was worn, number of times coughed or sneezed, or level of virus in nasal swab samples. We successfully cultured and deep-sequenced PVA-associated virus.

Conclusions: These results demonstrate the feasibility of using PVA-embedded masks as a non-invasive platform for detecting SARS-CoV-2 in exhaled air in COVID-positive individuals regardless of symptom status.

Keywords: COVID-19; Face masks; Personal protective equipment; SARS-CoV-2; qRT-PCR analysis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

COVID-19 Testing
COVID-19* / diagnosis
Humans
Pandemics
RNA, Viral / analysis
RNA, Viral / genetics
SARS-CoV-2*

Substances

RNA, Viral