Comparison of the urinary microbiome in men who have sex with men with and without Chlamydia trachomatis infection.

PURPOSE: The urinary tract is colonized by microbial communities that impact urinary health. Previous studies have suggested that the bacterial composition of the male urinary microbiota is related to STIs. This study assessed the bacterial composition of the urinary microbiome in South African MSM with and without C. trachomatis. METHODS: This study used urine samples from MSM attending care at the King Edward VIII hospital and the Aurum Institute in Durban, South Africa. A total of 200 samples were tested for C. trachomatis infection using the Applied Biosystems™ TaqMan® Assays. Urinary microbiomes of 23 samples were characterized using 16 S rRNA (V3 and V4) gene sequencing on the Illumina MiSeq platform. RESULTS: Bacterial taxonomic analysis showed a high abundance of Streptococcus, Corynebacterium, and Staphylococcus in all the sequenced samples. Moreover, Prevotella and Lactobacillus were detected in urine samples of MSM. Alpha diversity metrics showed a slight increase in microbial diversity in C. trachomatis positive samples; however, this was not significant (ANOVA, P > 0.05). Principal coordinates analysis (PCoA) showed that the microbiome of C. trachomatis infected MSM was not clearly different from those uninfected. Distinct bacterial communities were not detected between positive and negative samples (PERMANOVA F1,22= 1.0284, R2 = 0.047%, P = 0.385). CONCLUSION: Most microbiome studies on MSM to date have focused on the gut microenvironment. Few studies, however, have provided data regarding the normal composition of the male urethral microbiomes or if these microbiomes are associated with male STIs. This study adds to the growing body of knowledge highlighting the urinary microbiome in MSM.

The vaginal microbiome of South African pregnant women living with human immunodeficiency virus (HIV) with and without Chlamydia trachomatis infection.

BACKGROUND: Chlamydia genital infections continue to be a serious health concern globally. Previous studies have reported that Chlamydia trachomatis infection alters the vaginal microbiota of infected women. This study investigated differences in the vaginal microbiome of South African pregnant women living with HIV with and without C. trachomatis infection. METHODS: This was a cross-sectional study among 385 pregnant women, recruited from the King Edward VIII Hospital in Durban, South Africa. C. trachomatis was detected using the Applied Biosystems™ TaqMan® Assays. A total of 40 samples, 20 C. trachomatis positive and 20 C. trachomatis negative, were selected for sequencing. The sequencing of the vaginal microbiome was performed using the PacBio platform. Statistical analysis was performed on IBM SPSS version 26. RESULTS: The prevalence of C. trachomatis infection was 12.2% (47/385). The genus Gardnerella (32.14% vs. 24.02%) and species in the genus Gardnerella (31.97% vs. 24.03%) were more abundant in the C. trachomatis-infected group compared to the uninfected group. Lactobacillus iners were also more abundant in the C. trachomatis-infected women (28.30%) compared to the uninfected women. However, these observed patterns did not reach statistical significance. Discriminant analysis showed that the class Alpha-Proteobacteria; order Bacillales; family Enterococcaceae; the genera Enhydrobacter, Enterococcus, and Parabacteroides; Enterococcus spp.; and Pseudomonas stutzeri significantly contributed to a model separating C. trachomatis-infected women from the uninfected group (p < 0.05). CONCLUSION: The organisms and taxa that significantly contributed to separating the vaginal microbiota of C. trachomatis-infected women from the uninfected women in this study cohort have not been previously observed in association with C. trachomatis infection or the vaginal microbiota. Future studies in larger cohorts that will investigate the role of these microorganisms in C. trachomatis infection and the vaginal microbiota are required.

Prevalence and associated risk factors of chlamydia and gonorrhoea infections among men who have sex with men in Durban, South Africa.

Despite significant research on the prevalence of STIs in South African men who have sex with men (MSM), recent data on the prevalence and risk factors for curable STI infections among this key populations are limited. This study determined the prevalence of and risk factors associated with Neisseria gonorrhoeae and Chlamydia trachomatis infections among MSM. The sample consisted of 200 MSM resident in Durban. Data were collected using a self-administered questionnaire, and urine samples were collected and tested for N. gonorrhoeae and C. trachomatis. The prevalence of N. gonorrhoeae and C. trachomatis were 3.0% and 6.0%, respectively. Younger age was significantly associated with testing positive for C. trachomatis (p=0.037). Being between the ages of 30-39 years old reduced the risk of acquiring C. trachomatis infection (OR: 0.10, 95% CI: 0.0120-0.7564, p=0.026). In addition, being circumcised reduced the risk of contracting C. trachomatis (adjusted OR: 0.01, 95% CI: 0.0005-0.3516, p=0.01). However, having between 2-4 sex partners increased the risk of testing positive for C. trachomatis (adjusted OR: 107.45, 95% CI: 1.3467-8573.3130, p=0.036). The following factors were significantly associated (p<0.05) with testing positive for N. gonorrhoeae infection: cohabiting with sex partner, engaging in group sex, and drug use. Fear and stigma were the main barriers to accessing health care in the studied population. This study provided evidence of high rates of C. trachomatis infection among MSM resident in Durban. Based on the results, South African MSM, especially the young MSM population, should be given priority when delivering intervention programs to prevent STIs.

Malgré des recherches importantes sur la prévalence des IST chez les hommes sud-africains ayant des rapports sexuels avec des hommes (HSH), les données récentes sur la prévalence et les facteurs de risque d'infections IST curables parmi ces populations clés sont limitées. Cette étude a déterminé la prévalence et les facteurs de risque associés aux infections à Neisseria gonorrhoeae et à Chlamydia trachomatis chez les HARSAH. L'échantillon était composé de 200 HSH résidant à Durban. Les données ont été collectées à l'aide d'un questionnaire auto-administré et des échantillons d'urine ont été collectés et testés pour N. gonorrhoeae et C. trachomatis. La prévalence de N. gonorrhoeae et de C. trachomatis était respectivement de 3,0 % et 6,0 %. Un âge plus jeune était significativement associé à un test positif pour C. trachomatis (p = 0,037). Le fait d'être âgé de 30 à 39 ans réduisait le risque de contracter une infection à C. trachomatis (OR : 0,10, IC à 95 % : 0,0120-0,7564, p = 0,026). De plus, être circoncis réduisait le risque de contracter C. trachomatis (OR ajusté : 0,01, IC à 95 % : 0,0005-0,3516, p=0,01). Cependant, avoir entre 2 et 4 partenaires sexuels augmentait le risque d'être testé positif pour C. trachomatis (OR ajusté : 107,45, IC à 95 % : 1,3467-8573,3130, p=0,036). Les facteurs suivants étaient significativement associés (p < 0,05) au test positif pour l'infection à N. gonorrhoeae : cohabitation avec un partenaire sexuel, participation à des relations sexuelles en groupe et consommation de drogues. La peur et la stigmatisation étaient les principaux obstacles à l'accès aux soins de santé dans la population étudiée. Cette étude a mis en évidence des taux élevés d'infection à C. trachomatis parmi les HSH résidant à Durban. Sur la base des résultats, les HSH sud-africains, en particulier la jeune population HSH, devraient être prioritaires lors de la mise en œuvre de programmes d'intervention visant à prévenir les IST.

Prevalence of Syphilis in Pregnant Women Living With Human Immunodeficiency Virus (HIV) From South Africa Using a Molecular-Based Assay.

BACKGROUND: Syphilis is one of the most common sexually transmitted infections (STIs), and it remains a significant public health concern, particularly in low-resource settings including sub-Saharan Africa. There are limited data on the prevalence of syphilis among pregnant women living with HIV in South Africa. This study determined the prevalence of syphilis infection in pregnant women living with HIV by the polymerase chain reaction (PCR). METHODS: This was a cross-sectional study that included 385 pregnant women living with HIV recruited from the antenatal clinic at the King Edward VIII Hospital in Durban, South Africa between October 2020 and April 2021. Treponema pallidum was detected using the Applied BiosystemsTM TaqMan® Assays from stored DNA samples extracted from vaginal swabs. RESULTS: The prevalence of syphilis was 5.2% (20/385). The overall median (Q1-Q3) age of the women was 30.0 years (25.0-36.0). Of the women who tested positive for syphilis, 60.0% had reported STI symptoms (p = 0.030) and of those, 65.0% did not perceive themselves at risk of contracting STIs (p = 0.019). Women who reported having STI symptoms were more likely to test positive for syphilis when compared to women who reported not having any STI symptoms (OR: 2.810; 95% CI 1.119-7.052; p = 0.028). Women who perceived themselves as being at risk of contracting STIs were less likely to test positive for syphilis when compared to women who did not perceive themselves at risk of contracting STIs (OR: 0.328; 95% CI 0.128-0.842; p = 0.020). CONCLUSION: The study has indicated syphilis is prevalent among pregnant women living with HIV in Durban, South Africa however STI risk perception is low. Educational programs on STIs are essential among pregnant women attending antenatal care clinics in Durban.

Prevalence of Chlamydia trachomatis infection in pregnant women from Durban, South Africa.

INTRODUCTION: The Sub-Saharan African region has some of the world's highest prevalence of sexually transmitted infections (STIs). These infections are considered a major public health concern. Previous studies on the prevalence of C. trachomatis infection in Sub-Saharan Africa have reported rates ranging from 3.1% to 36.8% in pregnant women. This study investigated the prevalence and risk factors associated with C. trachomatis infection in pregnant women. METHODS: This study included 735 stored clinical samples that were collected from pregnant women attending the antenatal clinic at King Edward VIII Hospital in Durban from 2018 -2021. C. trachomatis was detected using the Applied BiosystemsTM TaqMan® Assays from stored DNA samples. RESULTS: A total of 81/735 (11%) samples tested positive for C. trachomatis infection. The overall median (Q1-Q3) age of the women was 29.0 years (24.0-35.0). The majority of the women who tested positive for C. trachomatis were younger, median (Q1-Q3) age 26.0 years (23.0-32.0) vs 30.0 years (25.0-35.0) for the negative women (p < .001). Of the positive women, 96.3% were unmarried (p=0.014). Older women were less likely to test positive for C. trachomatis infection (OR: 0.93; 95% CI 0.89-0.96 p = .001). Women who were married (OR: 0.25; 95% CI 0.06-0.70; p = .022), co-habiting with their partner (OR: 0.60; 95% CI 0.36-0.98; p = .048) and started having sex at older than 15 years (OR:0.26; 95% CI 0.09-0.87; p = .018) were less likely to test positive for C. trachomatis compared to their counterparts. CONCLUSION: This study showed that behavioural and clinical factors were associated with prevalent infections. In order to reduce prevalent infections, stronger risk reduction counselling messages need to be provided from the educational and public health sector.

Detection of metronidazole resistance in Trichomonas vaginalis using uncultured vaginal swabs.

Trichomonas vaginalis (T. vaginalis) is the most prevalent sexually transmitted infection (STI) globally. Metronidazole is the drug of choice for treating T. vaginalis infections although metronidazole-resistant T. vaginalis has been reported in clinical isolates. The purpose of this study was to determine the presence of mutations in nitroreductase genes associated with metronidazole resistance in vaginal swabs testing positive for T. vaginalis. This study included 385 human immunodeficiency virus (HIV)-positive pregnant women. Vaginal swabs were collected from consenting pregnant women and used for the detection of T. vaginalis using the TaqMan assay. From the vaginal swabs, nitroreductase genes ntr4 and ntr6 containing mutations associated with metronidazole resistance were amplified using a quantitative polymerase chain reaction (PCR) assay. To validate the PCR assay, T. vaginalis cultured isolates with known metronidazole resistance profiles were used as controls in the mutation detection assays. The prevalence of T. vaginalis in the study population was 12.2% (47/385). Mutations associated with resistance to metronidazole were detected in more than 40% of the samples tested, i.e. 21/47 (45%) and 24/47 (51%) for ntr4 and ntr6, respectively. A total of 19 samples (40%) carried mutations for both ntr4 and ntr6 genes associated with metronidazole resistance. The validation assays showed a positive correlation between phenotypic and genotypic resistance profiles. This study found a high prevalence of mutations associated with metronidazole resistance. This is concerning since metronidazole is currently used in the syndromic management of STIs in South Africa. Molecular-based assays for monitoring metronidazole resistance profiles using nitroreductase genes may serve as a feasible method for antimicrobial surveillance studies for T. vaginalis.

A review on Trichomonas vaginalis infections in women from Africa.

BACKGROUND: Trichomoniasis is the most common sexually transmitted infection (STI) with an estimated annual incidence of 276.4 million cases globally and about 30 million cases in sub-Saharan Africa. Trichomoniasis has been found to be associated with various health complications including pelvic inflammatory disease (PID), significant pregnancy complications, cervical cancer, prostatitis, infertility and the acquisition of human immunodeficiency virus (HIV). AIM: Despite being a highly prevalent infection in the African continent, there is no review article published that solely focusses on Trichomonas vaginalis (T. vaginalis) infections in women from Africa. This review aims to fill this gap in the literature. METHOD: An electronic search of online databases was used to identify and extract relevant research articles related to the epidemiology, health complications and treatment associated with T. vaginalis in women from Africa. RESULTS: Within the African continent, South Africa has reported the highest prevalence rate for this infection. A combination of sociodemographic, behavioural and biological factors has been shown to be associated with infection. Trichomonas vaginalis infection is associated with the acquisition of HIV, cervical cancer and PIDs in various female populations across the continent. Emerging patterns of resistance to metronidazole have been reported in women from South Africa. Currently, there is no effective vaccine against this pathogen despite efforts at vaccine development. CONCLUSION: Based on the high prevalence and health consequences associated with T. vaginalis, there is a need for improved screening programmes that will lead to early diagnosis, detection of asymptomatic infections and effective treatment regimens.

Distribution of genotypes in relation to metronidazole susceptibility patterns in Trichomonas vaginalis isolated from South African pregnant women.

Reports on metronidazole resistance of Trichomonas vaginalis strains have been on the increase. This study investigated the in vitro metronidazole resistance patterns in T. vaginalis isolates obtained from South African pregnant women and the genotypes of these isolates. This study included 362 pregnant women recruited from a hospital in Durban, South Africa. The women provided self-collected vaginal swabs for the detection of T. vaginalis by culture in Diamonds media. Cultured isolates were then subjected to anaerobic susceptibility assays to metronidazole. For the genotyping assays, the actin gene was digested by HindII, MseI, and RsaI. The banding patterns obtained after digestion was used to determine the genotypes. A total of 21/362 (5.8%) pregnant women tested positive for T. vaginalis infection. Of the 21 T. vaginalis isolates tested for metronidazole susceptibility, 9.5% (2/21) had a minimum inhibitory concentration (MIC) of 4 µg/ml (resistant), 38.1% (8/21) had a MIC of 2 µg/ml (intermediate), and 52.4% (11/21) had a MIC ≤ 1 µg/ml (susceptible). The dominant genotype that was identified across the isolates was genotype G. There was no correlation between genotype harboured and metronidazole susceptibility patterns. In this study, resistance to metronidazole was observed in clinical isolates of T. vaginalis. This study did not find a correlation between genotype harboured and metronidazole susceptibility patterns. Despite the lack of association, our study provides data on an area of research that is currently lacking in our setting.

Lack of association between Mycoplasma hominis and Trichomonas vaginalis symbiosis in relation to metronidazole resistance.

Resistance mechanisms of Trichomonas vaginalis to metronidazole are still not well understood. It has been shown that Mycoplasma hominis has the ability to establish an endosymbiotic relationship with T. vaginalis. This study investigated the association between T. vaginalis and M. hominis symbiosis in relation to metronidazole resistance. This study included 362 pregnant women from the King Edward VIII hospital in South Africa. The women provided self-collected vaginal swabs for the diagnosis of T. vaginalis by culture. Metronidazole susceptibility using the broth-microdilution assay was performed. Detection of the 16S rRNA from M. hominis using T. vaginalis genomic DNA as the template was performed. All statistical analysis was conducted in R statistical computing software. A total of 21 culture positive isolates were obtained resulting in a prevalence of 5.8% for T. vaginalis in the study population. Under anaerobic incubation, 52.4% (11/21) of the isolates were susceptible to metronidazole (MIC ≤ 1 µg/ml). Intermediate resistance (MIC of 2 µg/ml) and full resistance (4 µg/ml) was observed in 38.1% (8/21) and 9.5% (2/21) of the isolates, respectively. The majority of the isolates 95% (19/20) were susceptible to metronidazole under aerobic conditions. Only one isolate had a MIC of 50 µg/ml. M. hominis was shown to be present in 85.7% (18/21) of the T. vaginalis isolates. However, there was no significant association between metronidazole susceptibility and T. vaginalis-M. hominis symbiosis. This study provides evidence of emerging metronidazole resistance in T. vaginalis. However, these resistance profiles were not associated with M. hominis symbiosis.

Genotypic Variation in Trichomonas vaginalis Detected in South African Pregnant Women.

Background: Trichomonas vaginalis is the causative agent of trichomoniasis. The genetic characterisation of T. vaginalis isolates reveals significant genetic diversity in this organism. Data on the prevalence of different genotypes of T. vaginalis in South African populations is lacking. This study investigated the diversity of T. vaginalis in a pregnant population in South Africa. Methods: In this study, 362 pregnant women from the King Edward VIII Hospital in Durban, South Africa, provided vaginal swabs to be tested for the presence of T. vaginalis. T. vaginalis was detected using the TaqMan assay using commercially available primers and probes specific for this protozoan (Pr04646256_s1). The actin gene from T. vaginalis was amplified with gene-specific primers. The actin amplicons were digested with HindII, MseI, and RsaI, and the banding patterns were compared across the three digests for assignment of genotypes. Phylogenetic analysis was conducted using MEGA. Results: The prevalence of T. vaginalis in the study population was 12.9% (47/362). Genotype G was the most frequent genotype in our study population. Genotypes H and I were detected in one sample each. According to the multiple sequence alignments and phylogenetic analysis, a level of diversity was observed across and within genotypes. Four different single-nucleotide changes in the actin gene were detected. Sample TV358 (H genotype) contained a single amino acid substitution from glutamine to lysine. Sample TV184 (G genotype) contained a single amino acid substitution from glutamic acid to arginine. Sample TV357 (G genotype) contained two amino acid substitutions, arginine to leucine and glycine to aspartic acid. Conclusion: Three different genotypes were observed in the pregnant population. Diversity was observed across and within genotypes. The observed diversity can be challenging for future vaccine design and development of antigen-based rapid diagnostic tests for trichomoniasis.