Peer Review #2 of "Characteristics of the vaginal microbiome in cross-border female sex workers in China: a case-control study (v0.2)"

Abstract

Background : The female sex workers (FSWs) are key groups in the transmission of sexual transmitted infections (STI) and vaginal microbiome variations play an important role for it. We aimed to explore the characteristics of vaginal microbiome among FSWs. Materials and Methods: 24 cross-border female sex workers were randomly selected from a crosssectional survey for female sex workers in southwest China. 37 female non-sex workers were randomly selected from the gynecology clinic and health examination center. Vaginal swabs were collected, bacterial DNA extracted and 16S rRNA genes were sequenced. Differences in the vaginal microbiome between both groups were compared using bioinformatics analysis. Results: One DNA sample was excluded due to unqualified concentration, therefore 60 samples were sequenced. Female sex workers had significantly different vaginal microbiota β diversity, but undifferentiated α diversity when compared with non-sex workers. The average relative abundance of Sneathia, Shigella, Neisseria, Chlamydia, Prevotella, Enterococcus and Ureaplasma among female sex workers was higher than female non-sex workers, and relative abundance of Atopobium in female sex workers was lower than female non-sex workers. The Lactobacillus genus was the major genus in both groups. At the species level, Lactobacllus crispatus, Lactobacllus gasseri and Lactobacllus jensenii, in female sex workers, were lower when compared to female non-sex workers. Conclusion: There were distinct differences in vaginal bacteria variety between female sex workers and female non-sex workers. Some disease-related genus were also more abundant in female sex workers. Based on these observations, further research is required to identify microbiome communities related to high STI risks and other diseases in these cohorts.