Assessing the performance of regular surgical nose masks as a sampling method for SARS CoV-2 detection in a cross-sectional stu
Date
2023
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
PLOS ONE
Abstract
Nose masks are widely worn for protection against respiratory pathogens, including SARS CoV-2. They have been reported as possible substrates for viral sampling and testing for
COVID-19 but, evaluations have so far been purposive; involving individuals known to have
the infection and using improved materials on the nose masks to trap the virus. We investi gated the feasibility of using the regular 3-ply surgical masks and, voluntary coughing as a
mode of particle expulsion for detecting SARS-CoV-2 infections in a cross-sectional study at
Ghana’s first COVID-19 testing reference laboratory, the Noguchi Memorial Institute for Med ical Research, University of Ghana. Paired samples of naso-oropharyngeal swabs and nose
masks already worn by 103 consenting adult participants (retro masks) were collected. Par ticipants were also required to produce three strong coughs into a newly supplied sterile sur gical nose mask. Pre-wetted swabs in Viral Transport Media (VTM) were used in swabbing
the inner lining of each nose mask. The swabs used were then stored in VTM to maintain the
integrity of the samples. PCR results of SARS-CoV-2 detection from the nose masks were
compared to those from naso-oropharyngeal swabs (‘gold-standard’). Out of the 103 partici pants tested with all three methods, 66 individuals sampled with naso-oropharyngeal swabs
were detected as positive, and the retro and new masks matched 9 and 4, respectively. Only
3 individuals were positive across all three sampling methods accessed. The retro nose
masks performed better in matching the gold-standard results than the new mask + coughing
method, with 90% vs 80% sensitivity, positive predictive value of 13.6% vs 6%, and a weak
but significant linear relationship (adj. R2 = 0.1; P = 0.0004). Importantly, we also show that
the nose masks would work for sampling whether individuals are symptomatic or asymptom atic since gold-standard PCR cycling threshold (Ct) values for positive individuals did not dif fer between the two groups (P< 0.05). We recommend including features such as talking
during participant engagement, use of a spontaneous cough inducer and increased coughing
bouts > 3, to improve the performance of sterile nose masks for SARS-CoV-2 detection.
Description
Research Article
Keywords
respiratory pathogens, SARS-CoV-2 infections, Ghana, Viral Transport Media (VTM)
Citation
Citation: Opoku M, Obeng-Aboagye E, Boamah GYK, Adu-Asamoah D, Ismail RbY, Akpo MS, et al. (2023) Assessing the performance of regular surgical nose masks as a sampling method for SARS-CoV-2 detection in a cross-sectional study. PLoS ONE 18(10): e0293001. https://doi.org/ 10.1371/journal.pone.0293001