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

https://doi.org/10.1016/j.ajic.2022.01.010Get rights and content
open access

Highlights

  • Face-mask testing is an innovative way to detect virus in infected individuals.

  • SARS-CoV-2 viral RNA and infectious virus are efficiently recovered from masks.

  • Amount of virus on masks is variable across individuals and timing post-infection.

  • Mask-associated virus can be deep-sequenced to identify rare variants.

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.

Key words

SARS-CoV-2
COVID-19
Personal protective equipment
Face masks
qRT-PCR analysis

Cited by (0)

Funding/support: The authors acknowledge that funds for the project were provided by a grant from the German Federal Ministry of Health (BMG), facilitated via the World Health Organization. External partners include Dr. Brian Montague (University of Colorado), Dr. Kellie Hawkins (Denver Health Medical Center), and Jeannine Reiss and Joni Triantis Van Sickle (Colorado State University). Open access of this article is sponsored by the World Health Organization.

Conflicts of interest: None to report.