Prevalence and incidence of Trichomonas vaginalis infections in women participating in a clinical trial in Durban, South Africa

Trichomonas vaginalis in bronchoalveolar lavage fluid of a patient with severe pneumonia detected by metagenomic next-generation sequencing: A case report

RATIONALE

Trichomonas vaginalis (T. vaginalis) is a common anaerobic parasitic protozoan. However, to the best of our knowledge, there are few reports documenting T. vaginalis infection outside the genitourinary tract. Severe pneumonia caused by T. vaginalis infection has been rarely reported.

PATIENT CONCERNS

The 80-year-old female patient had a 20-year history of type II diabetes; however, she was not on regular medication. She was hospitalized due to a coma which continued 2 hours caused by trauma after a car accident. After her admission, she was provided with continuous mechanical ventilation; during the ventilation, she was still in a coma, accompanied by repeated fever and presence of much yellow sticky phlegm. The head CT scan indicated temporal lobe hematoma and subarachnoid hemorrhage. The lung CT scan showed bilateral pulmonary inflammatory consolidation and mass lesions.

DIAGNOSES

She was initially diagnosed with severe pneumonia and acute respiratory distress syndrome. Subsequently, fiberoptic bronchoscopy was conducted, and bronchoalveolar lavage fluid (BALF) was collected and sent for metagenomic next-generation sequencing (mNGS). The result indicated the presence of abundant sequences from the T. vaginalis genome. Thus, she was diagnosed with pulmonary T. vaginalis infection.

INTERVENTION

Anti-infective ornidazole treatment has significantly improved her symptoms.

OUTCOMES

After treatment, the patient regained consciousness and was able to communicate, and there was no obvious expectoration, fever, or positive bronchus sign in the lungs. Thereby, she was discharged from the hospital.

LESSONS

Special attention should be paid to infections other than common bacterial infections, such as T. vaginalis. Moreover, infection of rare pathogenic microorganisms might show symptoms similar to common bacterial infection, leading to misdiagnosis, further highlighting the usefulness of mNGS in detecting pathogens in a timely, sensitive, and accurate manner.

Association between Chlamydia trachomatis, Neisseria gonorrhea, Mycoplasma genitalium, and Trichomonas vaginalis and Secondary Infertility in Cameroon: A case-control study

Objective

Data on the prevalence and etiology of infertility in Africa are limited. Secondary infertility is particularly common, defined as the inability of a woman to conceive for at least one year following a full-term pregnancy. We describe a prospective study conducted in Cameroon designed to test the hypothesis of an association between common treatable sexually transmitted infections (STI): Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), and Trichomonas vaginalis (TV) and secondary infertility in women.

Methods

In this case-control study, we enrolled women in Fako Division, Cameroon between November 2017 and December 2018 with secondary infertility (cases) or current pregnancy (controls). We conducted a baseline survey to collect sociodemographic, and sexual and medical history information. Nucleic acid amplification testing using Aptima (Hologic, San Diego, CA, US) was performed on endocervical swabs for CT, NG, MG, and TV. Multivariable logistic regression was used to assess the relationship between active STI and secondary infertility.

Results

A total of 416 women were enrolled: 151 cases and 265 controls. Compared to controls, cases were older (median age 32 vs 27 years) and had more lifetime sexual partners (median 4 vs 3) (p<0.001). Cases were more likely to report dyspareunia, abnormal menses, prior miscarriage, and ectopic pregnancy (all p<0.05). STI positivity was not significantly different among cases and controls (2.7% vs 5.4% for CT, 1.3% vs 2.9% for NG, 6.0% vs 7.0% for MG, respectively), with the exception of TV which was more common in pregnant controls (0.7% vs 5%; p = 0.02).

Conclusion

Study findings did not support an association between active STI and secondary infertility in Cameroon. Given high rates of pre-existing tubal damage, routine STI screening and treatment in younger women may be more impactful than costly STI testing during infertility assessments.

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.

Prevalence and Risk Factors of Trichomonas vaginalis Among Female Sexual Workers in Nairobi, Kenya

BACKGROUND

Trichomonas vaginalis (TV) is the most common curable sexually transmitted infection (STI) worldwide. Trichomonas vaginalis infection is associated with an increased risk of pelvic inflammatory disease, human immunodeficiency virus transmission, and preterm birth in women. Data on the prevalence and risk factors for TV infection in sub-Saharan African countries remain scarce.

METHODS

A total of 350 Kenyan female sex workers, aged 18 to 50 years, participated in a 2-year longitudinal study of the acquisition of STIs, including TV infection. Every 3 months, cervical and vaginal brush samples were collected for STI testing. At baseline, a sociodemographic and behavior questionnaire was administered. Testing for TV, Chlamydia trachomatis (CT), Neisseria gonorrhoeae, Mycoplasma genitalium, and high-risk human papillomavirus was performed using APTIMA assays.

RESULTS

The TV baseline prevalence was 9.2% (95% confidence interval [95% CI], 6.3-12.7%) and 2-year cumulative TV incidence was 8.1 per 1000 person months (6.9-9.3). Risk factors for higher TV prevalence at baseline were CT infection (adjusted prevalence ratio [PR], 8.53; 95% CI, 3.35-21.71), human immunodeficiency virus seropositivity (PR, 3.01; 95% CI, 1.45, 6.24) and greater than 4 years of sex work (PR, 2.66; 95% CI, 1.07-6.60). Risk factors for elevated 2-year TV incidence were CT (hazard ratio [HR], 4.28; 95% CI, 1.36-13.50), high-risk human papillomavirus infection (HR, 1.91; 95% CI, 1.06-3.45) and history of smoking (HR, 2.66; 95% CI, 1.24-5.73).

DISCUSSION

CT infection was positively associated with both prevalent and 2-year incident TV infections.

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

There are insufficient data on the prevalence of Trichomonas vaginalis infection in pregnant women in South Africa. The present study aims to determine the prevalence of T. vaginalis (TV) in pregnant women and identify the risk factors associated with this infection in pregnancy. This was a cross-sectional study which included 362 pregnant women attending the antenatal clinic at the King Edward VIII Hospital in Durban, South Africa. A self-collected vaginal swab was provided by the enrolled women for laboratory diagnosis by real-time polymerase chain reaction. The protozoan load was determined as the logarithm of gene copies per milliliter. The prevalence of TV infection was 12.9% and 59.6% of the women who tested positive were asymptomatic ( p =  0.011). Women who presented with abnormal vaginal discharge had a 4.6 times likelihood of testing positive for TV infection (odds ratio 4.62; 95% confidence interval 1.83 to 11.70; p =  0.001). TV infection was high amongst pregnant women. Therefore, routine testing for this sexually transmitted infection is encouraged for proper management.

A review of the traditional use of southern African medicinal plants for the treatment of selected parasite infections affecting humans

ETHNOPHARMACOLOGICAL RELEVANCE

Worldwide, more than three billion cases of parasitic disease are reported yearly and it is likely that this figure is substantially under-estimated. Approximately one in six people globally are estimated to be infected with at least one parasite species annually. In South Africa, the prevalence of Schistosoma haematobium (bilharzia) and intestinal worms and helminths are particularly high, especially in children and in crowded or poorer rural communities with inadequate sanitation and nutrition. Despite alarmingly high estimates, medical research into parasitic diseases remains neglected and only malaria receives significant attention and funding. Traditional medicines have been used for centuries in Africa by multiple ethnic groups and many people rely on these healing systems as their primary healthcare modality. The traditional use of South African medicinal plants to treat parasite infestations is relatively well documented, and it is important to link these traditional uses to scientific evidence validating efficacy.

AIM OF THE STUDY

To document the medicinal plants used for parasitic infections and critically review the literature on the anti-parasitic properties of South African plants against some neglected parasitic diseases.

MATERIALS AND METHODS

A review of the literature (ethnobotanical books and publications documenting traditional plant use) was undertaken related to specific medicinal use for parasitic infections in Southern Africa. Inclusion criteria focused on human use. Exclusion criteria included veterinary use and malaria due to the extensive nature of these subject matters. An in-depth analysis of previous studies was undertaken and future prospectives are considered.

RESULTS

In particular, bilharzia, gastrointestinal worms and helminths, ectoparasites, trichomoniasis, leishmaniasis and trypanosomiasis are reviewed with special emphasis on the gaps in research.

CONCLUSIONS

Despite the availability of relatively extensive ethnobotanical records on the anti-parasitic properties of southern African medicinal plants, the antiparasitic properties of many plants have been poorly examined. There was in many instances a lack of evidence to support traditional use of many species towards some parasites and research is urgently needed in this area.

Prevalence of Trichomonas vaginalis infection and protozoan load in South African women: a cross-sectional study

OBJECTIVES

Trichomonas vaginalis is thought to be the most common non-viral sexually transmitted infection worldwide. We investigated the prevalence, risk factors and protozoan load of T. vaginalis infection in South African women.

METHODS

A cross-sectional study of 604 women was conducted at 25 primary healthcare facilities in rural South Africa (Mopani district). T. vaginalis DNA was detected in vaginal and rectal swabs. In univariate and multivariate analyses, the T. vaginalis infection was investigated in relation to demographic characteristics, medical history and behavioural factors. The T. vaginalis load was determined as the logarithm of DNA copies per microlitre sample solution.

RESULTS

Collected vaginal and rectal swabs were tested for T. vaginalis DNA. Prevalence of vaginal T. vaginalis was 20% (95% CI 17.0% to 23.4%) and rectal 1.2% (95% CI 0.6% to 2.4%). Most women (66%) with a vaginal infection were asymptomatic. Factors associated with T. vaginalis infection were a relationship status of single (OR 2.4; 95% CI 1.5 to 4.0; p<0.001) and HIV positive infection (OR 1.6; 95% CI 1.0 to 2.6; p=0.041). Women with vaginal T. vaginalis infection were more likely to have concurrent Chlamydia trachomatis rectal infection than those without vaginal infection (12%vs3%; p<0.001; OR 4.1). A higher median T. vaginalis load was observed among women with observed vaginal discharge compared with those without vaginal discharge (p=0.025).

CONCLUSIONS

Vaginal trichomoniasis is highly prevalent in rural South Africa, especially among single women and those with HIV infection, and often presents without symptoms.

Trichomoniasis - are we giving the deserved attention to the most common non-viral sexually transmitted disease worldwide?

ETIOLOGY

Trichomonas vaginalis is the etiologic agent of trichomoniasis, the most common non-viral sexually transmitted disease (STD) in the world. Transmission: Trichomoniasis is transmitted by sexual intercourse and transmission via fomites is rare. Epidemiology, incidence and prevalence: The WHO estimates an incidence of 276 million new cases each year and prevalence of 187 million of infected individuals. However, the infection is not notifiable. Pathology/Symptomatology: The T. vaginalis infection results in a variety of clinical manifestations - in most cases the patients are asymptomatic, but some may develop signs typically associated to the disease. Importantly, the main issue concerning trichomoniasis is its relationship with serious health consequences such as cancer, adverse pregnancy outcomes, infertility, and HIV acquisition. Molecular mechanisms of infection: To achieve success in parasitism trichomonads develop a complex process against the host cells that includes dependent- and independent-contact mechanisms. This multifactorial pathogenesis includes molecules such as soluble factors, secreted proteinases, adhesins, lipophosphoglycan that culminate in cytoadherence and cytotoxicity against the host cells. Treatment and curability: The treatment with metronidazole or tinidazole is recommended; however, cure failures remain problematic due to noncompliance, reinfection and/or lack of treatment of sexual partners, inaccurate diagnosis, or drug resistance. Therefore, new therapeutic alternatives are urgently needed. Protection: Strategies for protection including sexual behavior, condom usage, and therapy have not contributed to the decrease on disease prevalence, pointing to the need for innovative approaches. Vaccine development has been hampered by the lack of long-lasting humoral immunity associated to the absence of good animal models.

Evaluation of Presto(plus) assay and LightMix kit Trichomonas vaginalis assay for detection of Trichomonas vaginalis in dry vaginal swabs

This is an evaluation study of the Presto(plus) Assay for T. vaginalis by comparing to the TIB MOLBIOL LightMix Kit Trichomonas vaginalis Assay using 615 dry collected vaginal and rectal swabs. Discordant samples were analyzed by the Qiagen® Microbial DNA qPCR for TV Assay. Both assays showed comparable performances (McNemar p>0.05).

The incidence of Trichomonas vaginalis infection in women attending nine sexually transmitted diseases clinics in the USA

OBJECTIVES

Trichomoniasis (TV) is associated with an increased risk of acquisition of sexually transmitted diseases (STDs) and HIV. The purpose of this study is to evaluate factors associated with incidence TV among female STD clinic attendees in the USA.

METHODS

Data were collected from women participating in a randomised controlled trial evaluating brief risk reduction counselling at the time of HIV testing to reduce sexually transmitted infections (STIs) incidence in STD clinics. Participants recruited from STD clinics underwent STI testing at baseline and 6-month follow-up. TV testing was performed using Nucleic Acid Amplification Test.

RESULTS

1704 participants completed study assessments. Prevalence of TV was 14.6%, chlamydia 8.6%, gonorrhoea 3.0%, herpes simplex virus 2 44.7% and HIV 0.4%. Cumulative 6-month incidence of TV was 7.5%. Almost 50% of the incident TV cases had TV at baseline and had received treatment. Factors associated with incidence of TV were having chlamydia, TV and HIV at baseline: TV relative risk (RR)=3.37 (95% CI 2.35 to 4.83, p<0.001); chlamydia RR=1.92 (95% CI 1.23 to 2.99, p=0.04); and HIV=1.59 (95% CI 1.01 to 2.50, p=0.047).

CONCLUSIONS

Prevalent and incident TV is common among STD clinic attendees; and baseline TV is the main risk factor for incident TV, suggesting high rates of reinfection or treatment failures. This supports the importance of rescreening women after treatment for TV, evaluating current treatment regimens and programmes to ensure treatment of sexual partners.

CLINICAL TRIAL NUMBER

NCT01154296.

Correlates of incident Trichomonas vaginalis infections among African American female adolescents

BACKGROUND

Trichomonas vaginalis is the most common curable sexually transmitted infection associated with adverse reproductive health and pregnancy outcomes and may amplify HIV transmission. The objective was to identify correlates of incident T. vaginalis infections among African American adolescent girls.

METHODS

Data were collected via audio computer-assisted self-interviews at baseline and every 6 months for 18 months from 701 African American girls (14-20 years) in an HIV prevention trial. At each assessment, self-collected vaginal swabs were assayed for T. vaginalis, Chlamydia trachomatis, and Neisseria gonorrhoeae. Generalized estimating equations assessed associations between incident T. vaginalis infection and sociodemographic characteristics, substance use, partner-level factors, sexual risk behaviors, douching, and other sexually transmitted infections.

RESULTS

Of 605 (86.3%) participants who completed at least 1 follow-up assessment, an incident T. vaginalis infection was detected among 20.0% (n = 121). Factors associated with incident infection in adjusted analysis included the following: cigarette smoking (adjusted odds ratio [AOR], 1.66; 95% confidence interval [CI], 1.04-2.64), using alcohol on an increasing number of days in the past 3 months (AOR, 1.02; 95% CI, 1.00-1.04), acquisition of C. trachomatis (AOR, 2.27; 95% CI, 1.40-3.69) or N. gonorrhoeae (AOR, 5.71; 95% CI, 2.97-11.02), and T. vaginalis infection at the previous assessment (AOR, 3.16; 95% CI, 1.96-5.07).

CONCLUSIONS

Incident T. vaginalis infections were common. Strategies to reduce infection rates among this population may include improving partner notification and treatment services. The benefits of rescreening, screening adolescents screened for or infected with C. trachomatis or N. gonorrhoeae, and associations between substance use and T. vaginalis acquisition warrant further investigation.