Takashi Abe, Mirai Sekiguchi, Anna Wakui, Shingo Maruyama, Hiroto Sano, Miho Kawachi, Manami Imai, Yuki Kato, Haruna Sato, Rika Okabe, Yuki Abiko, Jumpei Washio, Kaori Tanaka, Nobuhiro Takahashi, Takuichi Sato
This study characterized the microbiota on lip-contact surfaces of worn non-woven fabric masks and evaluated the effects of commercially available mask sprays. Masks worn by six healthy volunteers were sampled, cultured anaerobically, and analyzed by 16S rRNA gene PCR-RFLP and sequence analysis, since anaerobic cultures are known to yield a larger and more diverse microbial community of the microbiota on worn non-woven fabric masks (Maruyama et al. 2022). The mean bacterial concentration on worn masks was (1.4 ± 0.9) × 103 CFU/mL. Among 299 isolates, Cutibacterium (75.3%) and Staphylococcus (19.4%) were predominant. Several sprays markedly reduced bacterial counts (to 10¹-10² CFU/mL), whereas others showed limited effects. Overall, mask sprays variably reduced bacterial contamination on lip-contact surfaces of worn non-woven fabric masks.