Prolonged mask wearing changed nasal microbial characterization of young adults during the COVID-19 pandemic in Shanghai, China

Abstract

BackgroundFace masks have become a common sight during the Coronavirus Disease 2019 (COVID-19) pandemic in many countries. However, the impact of prolonged face mask wearing on nasal microbiota of healthy people is not fully understood.MethodsIn this study, we compared the nasal microbiota of 82 young adults who wore face masks for an extended period of time to 172 mask-free peers from the same school recruited before the COVID-19 pandemic via 16S ribosomal RNA gene sequencing. Diversity, composition, and function of nasal microbiota between the two groups were analyzed. Prevalence of commensal bacteria colonized in the nasal cavity was determined by culture-based analysis.ResultsWe observed that prolonged face mask wearers had significantly different nasal microbial characterization and metabolic function compared to mask-free controls from 2018. Specifically, the nasal microbiota of the prolonged mask wearers displayed increased abundance of Staphylococcus, Pseudoalteromonas, Corynebacterium, etc. Meanwhile, the abundance of several genera including Bacteroides, Faecalibacterium, and Agathobacter was decreased. Moreover, we observed that COVID-19 infection history did not affect the composition of nasal microbiota significantly. Additionally, the culture-based analysis revealed that Staphylococcus aureus and Corynebacterium accolens increased, and Staphylococcus epidermidis decreased in the nasal cavity of prolonged mask wearers.ConclusionsOverall, our study suggests that prolonged face mask wearing can significantly alter the nasal microbiota.

The impact of the COVID-19 pandemic on Staphylococcus aureus infections in pediatric patients admitted with community acquired pneumonia

“…Interestingly, S. aureus colonization rates in neonatal intensive care unit patients remained unaffected by visitor restrictions during the COVID-19 pandemic 19 . Additionally, prolonged mask-wearing significantly altered the nasal microbial composition in healthy young adults, with a notable increase in S. aureus detected through culture-based analysis 20 . Therefore, the reductions observed in S. aureus isolates, which were absent in the positivity rate, might be attributed to the decreased number of children admitted with CAP during the COVID-19 pandemic rather than the direct blocking effects of NPIs during this period.…”

The Bacterial Burden of Worn Face Masks – Observational Research and Literature Review

“…Put simply: (i) the mask act as a filter trap with bacteria accumulating on its external and internal surfaces; (ii) the mask then acts as a "microbiological incubator" at the entrance of the airways; (iii) microorganisms may grow within the mask, nourished by skin debris, mucus and "exhaled breath condensate" [17,39,40,42,46,[105][106][107]. These trapped organisms/pathogens then may be inhaled, promoting infection of the respiratory tract [18,38] or, when distributed via air streams [108][109][110]117,135,136,168,169] the eye [79][80][81][82]116,135].…”

“…These trapped organisms/pathogens then may be inhaled, promoting infection of the respiratory tract [18,38] or, when distributed via air streams [108][109][110]117,135,136,168,169] the eye [79][80][81][82]116,135]. In addition, the skin microbiome is disrupted, potentially leading to or promoting other infections and allergic conditions [39,74,107,133,170].…”

“…This organic richness was visualised in our Bengal Rose staining. Growth, rather than mere survival [39,40,42,46,105,107] of bacterial and fungal colonies is revealed by scanning electron microscopy of face masks (FFP2) worn for several hours [41].…”

“…Eye conditions also have been associated with mask use [79][80][81][82]116,[134][135][136][137][138], whilst Islam et al found indirect evidence of changes in the oral microbiome [139]. Sukul et al changes in the gut microbiome (metabolic alterations) [20] whilst Xiang et al found change of the nasal microbial communities after prolonged mask wearing [107]. Lastly, face masks are mentioned as possible factors behind an increase in mucormycosis cases during the COVID-19 pandemic particularly in immunocompromised or otherwise vulnerable individuals [67,68,140].…”