Prevention of recurrence of bacterial vaginosis using lactobacilli-containing vaginal tablets among women with HIV: a randomized, placebo-controlled, double-blinded phase IV trial.

OBJECTIVES: The effectiveness of lactobacilli-containing vaginal tablets (VT) in bacterial vaginosis (BV) recurrence prevention among women infected with HIV treated with standard oral metronidazole in Pune, India was studied. METHODS: Women infected with HIV with confirmed BV diagnosis (Nugent score ≥7 and Amsel criteria >3) were enrolled in a 12-month, double-blind, randomized, placebo-controlled, phase IV study between 2018 and 2021. After a standard course of oral metronidazole for 7 days (400 mg three times a day), women were randomly assigned to either lactobacilli-containing or placebo VT arms to receive VTs for 4 months. BV recurrence was assessed after the initial cure from BV. RESULTS: Of the 464 women infected with HIV, 80 women with confirmed BV were enrolled. The retention was affected due to the COVID-19 pandemic (6-month retention rates 78%). The cure was seen in 85% and 93.5% of participants from the treatment and placebo arms, respectively, after four VT cycles. BV recurrence was seen in 41.4% and 44.8% in the treatment and placebo arm, respectively, with no significant difference in the two groups. CONCLUSION: The lactobacilli-containing VT was acceptable and safe; however, the addition of VT over standard oral metronidazole did not show any additional benefit in the prevention of BV recurrence in women infected with HIV, indicating the need for long-term randomized trials among them. Registered at Clinical Trials Registry- India, (CTRI) Number: CTRI/2018/04/013298.

The Penis, the Vagina and HIV Risk: Key Differences (Aside from the Obvious).

Globally, most Human Immunodeficiency Virus type 1 (HIV) transmission occurs through vaginal-penile sex (heterosexual transmission). The local immune environment at the site of HIV exposure is an important determinant of whether exposure during sex will lead to productive infection, and the vaginal and penile immune milieus are each critically shaped by the local microbiome. However, there are key differences in the microbial drivers of inflammation and immune quiescence at these tissue sites. In both, a high abundance of anaerobic taxa (e.g., Prevotella) is associated with an increased local density of HIV target cells and an increased risk of acquiring HIV through sex. However, the taxa that have been associated to date with increased risk in the vagina and penis are not identical. Just as importantly, the microbiota associated with comparatively less inflammation and HIV risk-i.e., the optimal microbiota-are very different at the two sites. In the vagina, Lactobacillus spp. are immunoregulatory and may protect against HIV acquisition, whereas on the penis, "skin type" flora such as Corynebacterium are associated with reduced inflammation. Compared to its vaginal counterpart, much less is known about the dynamics of the penile microbiome, the ability of clinical interventions to alter the penile microbiome, or the impact of natural/induced microbiome alterations on penile immunology and HIV risk.

Human Microbiota Network: Unveiling Potential Crosstalk between the Different Microbiota Ecosystems and Their Role in Health and Disease.

The human body is host to a large number of microorganisms which conform the human microbiota, that is known to play an important role in health and disease. Although most of the microorganisms that coexist with us are located in the gut, microbial cells present in other locations (like skin, respiratory tract, genitourinary tract, and the vaginal zone in women) also play a significant role regulating host health. The fact that there are different kinds of microbiota in different body areas does not mean they are independent. It is plausible that connection exist, and different studies have shown that the microbiota present in different zones of the human body has the capability of communicating through secondary metabolites. In this sense, dysbiosis in one body compartment may negatively affect distal areas and contribute to the development of diseases. Accordingly, it could be hypothesized that the whole set of microbial cells that inhabit the human body form a system, and the dialogue between the different host microbiotas may be a contributing factor for the susceptibility to developing diseased states. For this reason, the present review aims to integrate the available literature on the relationship between the different human microbiotas and understand how changes in the microbiota in one body region can influence other microbiota communities in a bidirectional process. The findings suggest that the different microbiotas may act in a coordinated way to decisively influence human well-being. This new integrative paradigm opens new insights in the microbiota field of research and its relationship with human health that should be taken into account in future studies.