The aetiology of bacterial vaginosis (BV) is not well-understood, and prevalence appears to be higher among women living in sub-Saharan Africa. A recent conceptual model implicates three main bacteria (Gardnerella vaginalis; Atopobium vaginae; and Prevotella bivia), sexual activity, sialidase activity, and biofilm formation in the pathogenesis of BV. We describe the vaginal microbiota, presence of the putative sialidase A gene of G. vaginalis, and biofilm among 386 adolescent girls aged 17 and 18 years in a cross-sectional study in Mwanza, Tanzania around the time of expected sexual debut. Vaginal swabs were collected and tested by quantitative polymerase chain reaction (qPCR) for five Lactobacillus species, G. vaginalis, A. vaginae, P. bivia, the sialidase A gene of G. vaginalis, and by fluorescence in situ hybridisation (FISH) for evidence of G. vaginalis and A. vaginae biofilm. We conducted a risk factor analysis of G. vaginalis, A. vaginae and P. bivia, and explored the associations between biofilm, the presence of the sialidase A gene, and non-optimal vaginal microbiota (Nugent 4–7). L. crispatus and L. iners were detected in 69 and 82% of girls, respectively. The prevalence of L. crispatus was higher than previously reported in earlier studies among East and Southern African women. G. vaginalis, A. vaginae, P. bivia were independently associated with reported penile-vaginal sex. Samples with all three BV-associated bacteria made up the highest proportion of samples with Nugent-BV compared to samples with each bacterium alone or together in pairs. Of the 238 girls with G. vaginalis, 63% had the sialidase A gene detected, though there was no difference by reported sexual activity (p = 0.197). Of the 191 girls with results for sialidase A gene and FISH, there was strong evidence for an increased presence of sialidase A gene among those with evidence of a biofilm (p < 0.001). There was a strong association between biofilm and non-optimal microbiota (aOR67.00; 95% CI 26.72–190.53). These results support several of the steps outlined in the conceptual model, although the role of sexual activity is less clear. We recommend longitudinal studies to better understand changes in vaginal microbiota and biofilm formation around the time of sexual debut.

细菌性阴道病（BV）的病因学尚未得到很好的理解，居住在撒哈拉以南非洲地区的女性患病率更高。最近的概念模型涉及三种主要细菌（阴道加德纳菌; 阴道异种毒素； 和 普氏杆菌），性活动，唾液酸酶活性和BV发病机理中生物膜的形成。我们描述了阴道微生物群，假定的唾液酸酶A基因的存在阴道G.在坦桑尼亚Mwanza进行的一项横断面研究中，对386名17岁和18岁的青春期女孩进行了生物膜涂膜，预计即将进行性试验。收集阴道拭子并通过定量聚合酶链反应（qPCR）测试五个乳杆菌 种类， G.阴道菌，A。阴道菌，P.bivia，唾液酸酶A基因 阴道G.，并通过荧光 原位 杂交（FISH）作为证据 阴道G. 和 A.阴道生物膜。我们进行了风险因素分析G.阴道，A。阴道 和 毕赤酵母，并探讨了生物膜，唾液酸酶A基因的存在与非最佳阴道菌群之间的关联（Nugent 4-7）。香菇 和 莱纳斯分别在69％和82％的女孩中被检测到。患病率香菇 高于先前在东部和南部非洲女性中进行的研究报告。 G.阴道菌，A。阴道菌，P.bivia与所报道的阴茎-阴道性行为独立相关。与单独或成对存在每种细菌的样本相比，具有所有三种与BV相关的细菌的样本占使用Nugent-BV的样本的比例最高。在238个女孩中，阴道G.，有63％的人检测到唾液酸酶A基因，尽管据报道的性活动没有差异（p= 0.197）。在191名获得唾液酸酶A基因和FISH结果的女孩中，有强有力的证据表明，在有生物膜证据的女孩中，唾液酸酶A基因的存在增加（p<0.001）。生物膜和非最佳菌群之间有很强的联系（aOR67.00； 95％CI 26.72–190.53）。这些结果支持概念模型中概述的几个步骤，尽管性活动的作用尚不清楚。我们建议进行纵向研究，以更好地了解性生活首次出现时阴道微生物群和生物膜形成的变化。