The Influence of Cervicovaginal Microbiota on Mucosal Immunity and Prophylaxis in the Battle against HIV
Purpose of Review
Young women in sub-Saharan Africa bear a disproportionate burden of the global HIV epidemic. In this review, we examine how cervicovaginal microbiota modulate structural and immune defenses in the female genital tract and influence HIV susceptibility.
Highly diverse, anaerobic cervicovaginal microbiota prevalent in sub-Saharan African women increase HIV acquisition risk by over fourfold. These bacteria weaken the barrier properties of the vaginal mucosa and increase local inflammation and HIV target cell recruitment, creating an environment permissive to HIV. These communities also diminish the prophylactic efficacy of topical tenofovir and therefore may modulate both biological susceptibility to HIV and the effectiveness of pre-exposure prophylaxis (PrEP).
Cervicovaginal bacteria influence multiple reproductive health outcomes, including HIV acquisition. High-diversity, low Lactobacillus abundance cervicovaginal communities prevalent in many regions with high HIV incidence are associated with increased HIV susceptibility. A better understanding of the host-microbial interactions mediating this risk is important to reduce HIV infections, particularly among women living in sub-Saharan Africa.
KeywordsHIV/AIDS Cervicovaginal microbiome Pre-exposure prophylaxis (PrEP) Genital inflammation
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no competing interests.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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