Prevalence and risk factors for Trichomonas vaginalis infection in pregnant women in South Africa

Trichomonas vaginalis infection among married women of Andaman and Nicobar islands

BACKGROUND

Trichomoniasis is a common sexually transmitted infection among both men and women, worldwide. The prevalence of trichomoniasis among married women in the remote Indian population is more important, yet they rarely sought treatment. This was the first-ever study conducted on the prevalence of Trichomonas vaginalis (TV) in the Andaman and Nicobar Islands.

METHODS

A cross-sectional study was undertaken among married women in the Andaman Islands, India from August 2020 to July 2022. Samples were collected from the suspected women attending community health centres after obtaining informed consent. PCR assay for TV was performed using specific primers and conditions. Further, sequencing was carried out and pair-wise genetic analysis was done using MEGA version 11 to find the TV strain.

RESULTS

Overall, 0.9% (nine out of 1000) TV cases were reported. The majority of infected population was below high school degrees (5/9) and was unemployed (7/9). Infected individuals never had a history of a sexually transmitted illness. Two of the ladies reported dyspareunia, and one of them had persistent pelvic pain. Of these, most of them had pelvic inflammatory disease (PID) and abnormal vaginal discharge. The pair-wise genetic distance analysis found the strain found on this island was TV G3.

CONCLUSIONS

From our knowledge, this surveillance study was conducted first time in the Andaman and Nicobar Island. The detection of the TV G3 strain may be essential for understanding the prevalence of TV infection and their associated risk factors. More research is needed to understand the TV-associated risk factors among suspected patients in hospital settings.

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 Biosystems^TM 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.

Sexually transmitted infections in pregnant women from sub-Saharan Africa

Background

Sexually transmitted infections (STIs) are a major health problem in most countries of the world, particularly in developing countries where the resources and technology to diagnose and treat them are limited. Currently, there is limited data on STIs and risk factors for these infections in pregnant women living with human immunodeficiency virus (HIV), especially in sub-Saharan Africa (SSA). This review provides data on the prevalence and risk factors for STIs in pregnant women living with HIV from SSA. This review also describes the association between STIs and HIV on pregnancy and birth outcomes as well as highlights the importance of laboratory-based diagnosis of STIs.

Method

An electronic search of online databases was used to find and collect relevant research articles connected to the prevalence, adverse pregnancy and birth outcomes, health complications and risk factors associated with STIs and HIV in pregnant women from SSA. The search was limited to articles published in English. Relevant studies were identified by searching literature from January 2001 to date. The search yielded 4709 results.

Results

In SSA, STIs are highly prevalent in pregnant women and are widely known to be linked with an increased risk of poor maternal and neonatal outcomes. These infections are often asymptomatic and highly prevalent in pregnant women. The screening of STIs in pregnant women living with HIV can reduce the risk of mother-to-child transmission (MTCT) and screening and treatment for STIs can also prevent adverse perinatal outcomes. It is important to recognise regional and national STI epidemics in order to promote STI prevention and control interventions considering the test and treat approach as opposed to syndromic management.

Conclusion

This review highlights the need to use diagnostic screening methods instead of syndromic STI management in SSA. Moreover, more research into effective prevention and treatment measures for STIs in pregnant women is urgently required.

'Mycoplasma hominis does not share common risk factors with other genital pathogens': Findings from a South African pregnant cohort

Background

The role of Mycoplasma hominis (M. hominis) as a genital tract pathogen was still debatable. This study identified the risk factors associated with the prevalence of M. hominis in South African pregnant women.

Methods

This was a cross-sectional analysis of n = 221 prenatal patients attending a Durban hospital during November 2017 to April 2018. M. hominis was detected from urine samples using the quantitative polymerase chain reaction. The population characteristics were described using frequencies stratified by the infection status of M. hominis. In addition, a univariate analysis was used to assess the relationship between each risk factor and infection status. The analysis further considered logistic regression to assess the influence of these risk factors univariately and in the presence of other factors. The coinfection rate between M. hominis and bacterial vaginosis (BV), Trichomonas vaginalis (T. vaginalis), Mycoplasma genitalium (M. genitalium) and Candida species was also determined. All the tests were conducted at 5% level of significance.

Results

The prevalence of M. hominis in this study population was 48% (106/221). In the univariate analysis, factors significantly associated with M. hominis positivity included having past abnormal vaginal discharge (p = 0.037), having current abnormal vaginal discharge (p = 0.010) and a borderline significance (p = 0.052), which were noted for previous pre-term delivery. However, none of these factors were sustained in the multivariate analysis. There was a statistically significant association between M. hominis and BV positivity (p < 0.001). Similarly, M. hominis and M. genitalium positivity was significant (p = 0.006).

Conclusion

This study showed that M. hominis does not share common risk factors with known genital tract pathogens in a population of pregnant women and therefore cannot be considered a genital tract pathogen.

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.

Prevalence and factors associated with Trichomonas vaginalis infection in indigenous Brazilian women

There is a scarcity of studies on the prevalence of Trichomonas vaginalis (TV) in indigenous populations of Brazil. We conducted a cross-sectional study between January and December 2018, on indigenous women living nearby an urban center of the Midwest region of Brazil and determined the prevalence of TV. Factors associated with TV infection and a comparison of molecular and direct microscopy diagnoses were determined. 241 indigenous women aged above 18 years participated in the study. Cervical and vaginal brush samples were collected to diagnose TV through polymerase chain reaction (PCR). Direct microscopy for detection of TV, and cellular changes was performed. A sociodemographic and behavioral questionnaire was applied at the beginning of the study. All the data were analyzed using Statistical Package for the Social Sciences. The result obtained showed that 27.8% [95% CI: 22.2-33.9] were positive for TV on PCR, while 7.41% [95% CI: 4.1-11] showed positive on direct microscopy. Direct microcopy also found 21 (8.71%) and 8 (3.31%) women infected with Gardnerella vaginalis and Candida albicans, respectively. In addition, 10 women presented atypical squamous cells of unknown significance and 14 lesions suggestive of HPV. Single women, under the age of 30 and who do not use condoms, were found to have a greater chance of getting TV infection. The high prevalence TV found in this population is comparable to highly vulnerable populations, as prisoners, sex workers and women in regions with low socioeconomic levels, moreover, seems to be an underdiagnosis of this infection. Therefore, a routine test program, as well as a review of the diagnostic method used, is encouraged for proper management.

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.