The significance of Lactobacillus crispatus and L. vaginalis for vaginal health and the negative effect of recent sex: a cross-sectional descriptive study across groups of African women

Abstract

BackgroundWomen in sub-Saharan Africa are vulnerable to acquiring HIV infection and reproductive tract infections. Bacterial vaginosis (BV), a disruption of the vaginal microbiota, has been shown to be strongly associated with HIV infection. Risk factors related to potentially protective or harmful microbiota species are not known.MethodsWe present cross-sectional quantitative polymerase chain reaction data of the Lactobacillus genus, five Lactobacillus species, and three BV-related bacteria (Gardnerella vaginalis, Atopobium vaginae, and Prevotella bivia) together with Escherichia coli and Candida albicans in 426 African women across different groups at risk for HIV. We selected a reference group of adult HIV-negative women at average risk for HIV acquisition and compared species variations in subgroups of adolescents, HIV-negative pregnant women, women engaging in traditional vaginal practices, sex workers and a group of HIV-positive women on combination antiretroviral therapy. We explored the associations between presence and quantity of the bacteria with BV by Nugent score, in relation to several factors of known or theoretical importance.ResultsThe presence of species across Kenyan, South African and Rwandan women was remarkably similar and few differences were seen between the two groups of reference women in Kenya and South Africa. The Rwandan sex workers and HIV-positive women had the highest G. vaginalis presence (p = 0.006). Pregnant women had a higher Lactobacillus genus mean log (7.01 genome equivalents (geq)/ml) compared to the reference women (6.08 geq/ml). L. vaginalis (43%) was second to L. iners (81.9%) highly present in women with a normal Nugent score. Recent sexual exposure negatively affected the presence of L. crispatus (<0.001), L. vaginalis (p = 0.001), and Lactobacillus genus (p < 0.001). Having more than one sexual partner in the last three months was associated with an increased prevalence of G. vaginalis (p = 0.044) and L. iners (p = 0.001).ConclusionsAlthough the composition of species across the studied African countries was similar, the presence of protective species i.e. L. crispatus and L. vaginalis in women with a normal Nugent score appeared lower compared to non-African studies. Furthermore, Lactobacillus species were negatively affected by sexual behavioural. Strategies to support protective Lactobacillus species are urgently needed.Trial registrationThe study is registered at the Trial Registration at the National Health Research Ethics Council South Africa with the number DOH2709103223.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-015-0825-z) contains supplementary material, which is available to authorized users.

The most Common Causes of Cervico-vaginal Infections Among Sudanese Women Complainingof Vaginal Discharge

“…Bacterial vaginosis is best described as a disruption of the vaginal microbiota or as a vaginal bacterial dysbiosis. It is characterised by a reduction or a replacement of the protective Lactobacillus species by an overgrowth of other anaerobic bacteria [17].…”

Cross-Sectional Analysis of Selected Genital Tract Immunological Markers and Molecular Vaginal Microbiota in Sub-Saharan African Women, with Relevance to HIV Risk and Prevention

“…The total Lactobacillus species, L. crispatus, L. iners, L. jensenii, L. gasseri, and L. vaginalis, the BV related species Atopobium vaginae, Gardnerella vaginalis, and Prevotella bivia, and Escherichia coli were measured and expressed as genome equivalents (geq)/ml using qPCR (12,71) T grown on Columbia agar (Becton Dickinson) at 37 Ϯ 2°C under anaerobic conditions (BugBox; LedTechno, Heusden-Zolder, Belgium). After extraction, the DNA concentrations were determined using NanoDrop (Thermo Fisher Scientific, Erembodegem, Belgium).…”

Species diversity of vaginal lactobacilli in norm and in dysbiotic states

“…Это объясняет-ся способностью L. crispatus поддерживать по-стоянство микробиоценоза влагалища за счет выраженных протективных свойств, препят-ствующих размножению условно-патогенных микроорганизмов [19,20].…”