Highly diverse and anaerobe-dominated vaginal microbiota in women living with HIV: a cross-sectional study

Although highly active antiretroviral therapy (HAART) suppresses HIV viral load and extends life, rising non-AIDS-defining events (NADEs) underscore the importance of long-term health, including reproductive tract health in women living with HIV (WLWH). This study compared vaginal microbiota in WLWH versus women without HIV infection (WLWNH) to inform reproductive health assessment and intervention.

Vaginal swabs from 76 WLWH and 74 WLWNH (Beijing Ditan Hospital, Sept-Oct 2022) underwent 16S rRNA gene sequencing. We used hierarchical clustering to categorize community state types (CSTs I-V) and Adonis for inter-group differences. Pearson correlation assessed relationships between CD4 + T cells and differential bacteria, while Spearman correlation evaluated microbial co-occurrence network interactions (visualized via Gephi0.10.1). Neutral community modeling evaluated assembly processes.

WLWH exhibited higher vaginal microbial diversity. Compared to WLWNH, Gardnerella vaginalis showed higher relative abundance in WLWH CST III (P = 0.001). Additionally, urogenital pathogens Aerococcus christensenii and Ureaplasma urealyticum were significantly enriched in WLWH CST III (P = 0.028, P = 0.033; AUC = 0.704, 0.721, respectively) and CST IV (P = 0.024, P = 0.031; AUC = 0.657, 0.646, respectively). In CST III, CD4 + T cell counts correlated positively with Aerococcus christensenii (r = 0.49, P = 0.044). Neutral community modeling demonstrated that microbiota assembly in WLWH was primarily shaped by stochastic processes (R² = 0.37 vs 0.219) with significantly restricted microbial dispersal (Nm = 9 vs14).

WLWH exhibit a distinct, highly diverse vaginal dysbiosis enriched with anaerobic and urogenital pathogenic bacteria. This post-HIV infection dysbiosis may predispose women to subsequent genital infections; future longitudinal research comparing pre- and post-infection microbiome dynamics will be crucial for optimizing gynecological management.