Association Between Trichomonas vaginalis and Vaginal Bacterial Community Composition Among Reproductive-Age Women

Abstract

Objectives Some vaginal bacterial communities are thought to prevent infection by sexually transmitted organisms. Prior work demonstrated that the vaginal microbiota of reproductive-age women cluster into five types of bacterial communities; 4 dominated by Lactobacillus species (L. iners, L. crispatus, L. gasseri, L. jensenii), and one (termed community state type (CST) IV) lacking significant numbers of lactobacilli and characterized by higher proportions of Atopobium, Prevotella, Parvimonas, Sneathia, Gardnerella, Mobiluncus, and other taxa. We sought to evaluate the relationship between vaginal bacterial composition and Trichomonas vaginalis. Methods Self-collected vaginal swabs were obtained cross-sectionally from 394 women equally representing four ethnic/racial groups. T. vaginalis screening was performed using PCR targeting the 18S rRNA and β-tubulin genes. Vaginal bacterial composition was characterized by pyrosequencing of barcoded 16S rRNA genes. A panel of eleven microsatellite markers was used to genotype T. vaginalis. The association between vaginal microbiota and T. vaginalis was evaluated by exact logistic regression. Results T. vaginalis was detected in 2.8% of participants (11/394). Of the eleven T. vaginalis-positive cases, eight (72%) were categorized as CST-IV, two (18%) as communities dominated by L. iners and one (9%) as L. crispatus-dominated (p-value:0.05). CST-IV microbiota were associated with an 8-fold increased odds of detecting T. vaginalis compared to women in the L. crispatus-dominated state (OR:8.26, 95% CI:1.07–372.65). Seven of the 11 T. vaginalis isolates were assigned to two genotypes. Conclusion T. vaginalis was associated with vaginal microbiota consisting of low proportions of lactobacilli and high proportions of Mycoplasma, Parvimonas, Sneathia, and other anaerobes.

Trichomonas vaginalis Infection among Pregnant Women in Jimma University Specialized Hospital, Southwest Ethiopia

“…On the other hand, the prevalence of this study was higher than the studies conducted in US 2.8% [21] and Iran 2.1% [22]. Also, the prevalence of this study was comparable with the study conducted in Iraq 5.4% [23] and Argentina 4% [24].…”

The adherence ofTrichomonas vaginalisto host ectocervical cells is influenced by lactobacilli

“…Lactobacilli create an acidic and oxidative environment and produce molecules that inhibit the growth and down-regulate the virulence of many microbial pathogens in a species/strain-specific manner 7. Although no reports have examined the interaction of lactobacilli and T vaginalis , modification of the vaginal environment during trichomoniasis, including its microbiota,2 4 6 implies that the inevitable encounter of these micro-organisms— T vaginalis and Lactobacillus— in the vagina will likely trigger a dramatic niche competition.…”

“…The disruption of this natural protective barrier is evidently associated with many urogenital infections7 including trichomoniasis 2 6. Lactobacilli can inhibit the growth and negatively affect the virulence of various pathogens 7.…”

“…Lactobacilli can inhibit the growth and negatively affect the virulence of various pathogens 7. Despite indirect evidence that T vaginalis and lactobacilli are competitors,2 6 this microbial interaction has not yet been investigated.…”

An overview of major metagenomic studies on human microbiomes in health and disease

“…The "community type" was also called "community state types (CSTs)" in some later studies. Some studies further investigated the associations between vagina CSTs and vaginal health in groups of particular ages [62,63], with the influence of HIV treatment [64,65], in pregnancy and birth [66][67][68], and so on.…”