Effects of wearing masks during COVID-19 pandemic on the composition and diversity of skin bacteria and fungi in medical workers.

Background: Although studies have shown that wearing masks can affect the skin microbiome, more detailed and comprehensive research on wearing masks needs to be further explored.

Objective: This study aimed to characterize the influence of mask wearing on the diversity and structural characteristics of the facial skin microbial community of medical staff during the COVID-19 pandemic by means of metagenomic sequencing (mNGS).

Methods: A total of 40 samples were taken by swabbing the cheek in the 2 × 2 cm area before and after wearing the masks. DNA was extracted for metagenomic sequencing.

Results: A statistically significant decrease was found in the α diversity between BN and AN groups and between B2 h and A2 h groups. BN and AN mean groups before and after 8 h of wearing the medical protective mask (N95), including 10 volunteers, respectively. B2 h and A2 h mean groups before and after 8 h of wearing masks, including 10 volunteers changing mask every 2 h, respectively. The β diversity was found to be statistically reduced between BS and AS groups ( = 0.025), BN and AN groups ( = 0.009), and B2 h and A2 h group ( = 0.042). The fungal beta diversity was significantly decreased in every group before and after wearing masks. The main bacteria on the face before and after wearing masks were (68.02 and 71.73%). Among the fungi, predominated the facial skin surface before and after wearing masks (35.81 and 39.63%, respectively).

Conclusion: Wearing different types of masks and changing masks according to different frequency will have different effects on the facial skin's microbiota.