Vaginal Microbiota of the Sexually Transmitted Infections Caused by and in Women with Vaginitis in Taiwan.

The three most common sexually transmitted infections (STIs) are (CT), (GC) and (TV). The prevalence of these STIs in Taiwan remains largely unknown and the risk of STI acquisition affected by the vaginal microbiota is also elusive. In this study, a total of 327 vaginal swabs collected from women with vaginitis were analyzed to determine the presence of STIs and the associated microorganisms by using the BD Max CT/GC/TV molecular assay, microbial cultures, and 16S rRNA sequencing. The prevalence of CT, TV, and GC was 10.8%, 2.2% and 0.6%, respectively. A culture-dependent method identified that and (GBS) were more likely to be associated with CT and TV infections. In CT-positive patients, the vaginal microbiota was dominated by , and the relative abundance of (12.46%) was also higher than that in TV-positive patients and the non-STIs group. However, spp. was significantly lower in TV-positive patients, while GBS (10.11%), (6.19%), (12.75%), and (5.31%) were significantly enriched. Using an in vitro co-culture assay, we demonstrated that the growth of was suppressed in the initial interaction with TV, but it may adapt and survive after longer exposure to TV. Additionally, it is noteworthy that TV was able to promote GBS growth. Our study highlights the vaginal microbiota composition associated with the common STIs and the crosstalk between TV and the associated bacteria, paving the way for future development of health interventions targeting the specific vaginal bacterial taxa to reduce the risk of common STIs.