Exploring the role of cervicovaginal microbiota as risk factor for cervical cancer in Sub-Saharan Africa: a systematic review and meta-analysis

Objective To estimate the association between cervico-vaginal microbiota and cervical cancer in Sub-Saharan Africa. Study design Systematic Review and Meta-Analysis. Method The databases, PubMed and African Journal Online (AJOL), as well as Google Scholar, were accessed. All primary studies (cross-sectional, cohort and case control) that reported cervical cancer, risk factors and cervico-vaginal microbiota in Sub-Saharan Africa, which were written in English language, were screened. Methodological and quality assessment of included studies was carried out using Joanna Briggs Institute (JBI) quality assessment tool. Random effects model meta-analysis was performed using MedCalc statistical software version 20.0.1 to evaluate the pooled prevalence of cervico-vaginal microbiota and prevalence was determined using the Freeman-Tukey double arcsine transformation. Heterogeneity between studies was assessed using the I-squared (I2) test and publication bias evaluated using Egger's statistical test. The study protocol was registered with the PROSPERO database (No: CRD42024495232). Results The review involved screening of a total of 1,151 articles and 15 articles, which met the inclusion criteria, were finally used for the review and meta-analysis. Cervico-vaginal risk factors noted in our study comprised infection with high risk human papilloma virus (hrHPV), human Immune virus (HIV), Trichomonas vaginalis, Porphyromonas, Prevotella, and Anaeromonas. The pooled prevalence of HPV in the included studies was 40% (95% Confidence interval [CI]- 24%, 56%) and pooled prevalence of HIV as a risk factor was 19% (95% CI- 3%, 44%). For each individual meta-analysis, high heterogeneity was observed with I2 of 98.97 (HPV) and 99.33 (HIV) at p-values <= 0.01. Egger's tests for regression intercept in funnel plots indicated no evidence of publication bias while JBI result showed high quality of included articles. Conclusion This systematic review and meta-analysis revealed that cervico-vaginal microbiota, such as Porphyromonas, Prevotella, and Trichomonas vaginalis, along with high-risk HPV and HIV infection, increase cervical cancer risk in Sub-Saharan Africa. To reduce this burden, integrating microbiota management, sexual health education and HPV vaccination, is crucial.