To Örebro University

Background: Bacterial vaginosis (BV) is a common vaginal disorder among women of reproductive age, and BV can be associated with adverse pregnancy outcomes and enhanced acquisition and transmission of STIs/HIV. The present study aimed to determine the prevalence of BV using the Nugent score and sociodemographic factors associated with BV among women in Maputo, Mozambique, and to evaluate the performance of the AmpliSens® Florocenosis/Bacterial vaginosis-FRT PCR kit versus Nugent score for diagnosis of BV.

Material and Methods: Vaginal swabs were collected from 886 non-pregnant symptomatic women during their visit to the Mavalane Health area in Maputo, Mozambique from February 2018 to January 2019. BV was diagnosed by Nugent score. The AmpliSens®Florocenosis/Bacterial vaginosis-FRT PCR kit (InterLabService, Moscow, Russia) was evaluated for BV diagnosis. HIV was detected using Determine HIV1/2 (Alere Medical Co. Ltd, Chiba, Japan) plus Uni-Gold HIV1/2 (Trinity Biotech, Ireland). The chisquare test was used to estimate associations between categorical variables.

Results: The prevalence of BV by PCR, Nugent score, and HIV was 47.2%, 39.1%, and 22.5%, respectively. Of those with BV, 52% were HIV-positive and 48% HIV-negative (p < 0.001). The highest proportion of women was under 24 years old (38.1%), single (49.5%), with secondary education (53.5%), and living in rural areas (55.4%). BV was associated with young age at first sexual intercourse (44.5%) (χ2 = 17.47, p=< 0.001), condom use (43.3%) (χ2 =3.7, p= 0.05), and no use of contraceptives (49%) (χ2= 13.6, p=0.02). In real-time PCR, a higher proportion of BV cases (47.2%) were detected. However, 12.5% of women had an unknown vaginal dysbiosis. The sensitivity and specificity of the PCR were 99.6% and 82.2%, respectively. Using the PCR as a reference test, the sensitivity and specificity of the Nugent score were 86.2% and 99.4%, respectively. The concordance of both tests was κ=0.825 (95% CI, 0.78 - 0.86), p<0.001.

Conclusions: A high prevalence of BV was associated with young age at first sexual intercourse, condom and contraceptive use among women in Maputo, Mozambique. The AmpliSens® Florocenosis/Bacterial vaginosis-FRT PCR assay detected more BV-positive cases than the Nugent score and needs further evaluation in other settings.