Bovine neutrophils kill the sexually-transmitted parasite Tritrichomonas foetus using trogocytosis

The protozoan parasite Tritrichomonas foetus (T. foetus) is the causative organism of bovine trichomonosis (also referred to as trichomoniasis), a sexually-transmitted infection that reduces fertility in cattle. Efforts to control trichomonosis on cattle farms are hindered by the discouragement of antibiotic use in agriculture, and the incomplete, short-lived protection conferred by the current vaccines. A more complete mechanistic understanding of what effective immunity to T. foetus entails could enable the development of more robust infection control strategies. While neutrophils, the primary responders to infection, are present in infected tissues and have been shown to kill the parasite in vitro, the mechanism they use for parasite killing has not been established. Here, we show that primary bovine neutrophils isolated from peripheral blood rapidly kill T. foetus in vitro in a dose-dependent manner, and that optimal parasite killing is reduced by inhibitors of trogocytosis. We also use imaging to show that bovine neutrophils surround T. foetus and trogocytose its membrane. These findings are consistent with killing via trogocytosis, a recently described novel neutrophil antimicrobial mechanism.

Stimulation of microvesicle secretion in Trichomonas vaginalis

Trichomonas vaginalis is an extracellular flagellate protozoan and the etiological agent of human trichomoniasis, a sexually transmitted infection (STI) with a high incidence. Several reports have shown that this protozoan releases microvesicles into the culture medium, which show high potential in modulating cell-to-cell communication and the host response to infections. However, the biogenesis of these vesicles has not been analyzed in detail. In the present study, high-resolution ion scanning microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the surface of control cells and cells incubated in the presence of Ca2+ alone or with A 23187 calcium ionophore. Two different strains of T. vaginalis were analyzed. Most control cells displayed relatively smooth surfaces, whereas cells incubated with Ca2+ had many surface projections of variable shape and size (from 40 nm to around 1 μm). Quantitative analyses were performed directly in the scanning electron microscope and showed a significant increase in the number of cells with surface projections after incubation in the presence of calcium. TEM showed that treated cells presented several cytoplasmic multivesicular structures, suggesting membrane fusion and exosomes in the extracellular medium. The amount and size of the released vesicles were quantitatively analyzed using light scattering and TEM on negatively stained samples. The observations show that incubation of both parasite strains in the presence of Ca2+ significantly increased the release of microvesicles into the extracellular medium in a time-dependent process. Sequential incubation in the presence of Ca2+ and the calcium ionophore A23187 increases the presence of vesicles on the parasite surface only at a short incubation time (5 min). Transmission electron microscopy showed that at least part of the vesicles are originated from cytoplasmic multivesicular structures. This information contributes to a better understanding of the biogenesis of extracellular vesicles secreted by T. vaginalis.

Exploring novel pyrazole-nitroimidazole hybrids: Synthesis and antiprotozoal activity against the human pathogen trichomonas vaginalis

Trichomoniasis, a prevalent sexually transmitted infection (STI) caused by the protozoan Trichomonas vaginalis, has gained increased significance globally. Its relevance has grown in recent years due to its association with a heightened risk of acquiring and transmitting the human immunodeficiency virus (HIV) and other STIs. In addition, many publications have revealed a potential link between trichomoniasis and certain cancers. Metronidazole (MTZ), a nitroimidazole compound developed over 50 years ago, remains the first-choice drug for treatment. However, reports of genotoxicity and side effects underscore the necessity for new compounds to address this pressing global health concern. In this study, we synthesized ten pyrazole-nitroimidazoles 1(a-j) and 4-nitro-1-(hydroxyethyl)-1H-imidazole 2, an analog of metronidazole (MTZ), and assessed their trichomonacidal and cytotoxic effects. All compounds 1(a-j) and 2 exhibited IC50 values ≤ 20 μM and ≤ 41 μM, after 24 h and 48 h, respectively. Compounds 1d (IC50 5.3 μM), 1e (IC50 4.8 μM), and 1i (IC50 5.2 μM) exhibited potencies equivalent to MTZ (IC50 4.9 μM), the reference drug, after 24 h. Notably, compound 1i showed high anti-trichomonas activity after 24 h (IC50 5.2 μM) and 48 h (IC50 2.1 μM). Additionally, all compounds demonstrated either non-cytotoxic to HeLa cells (CC50 > 100 μM) or low cytotoxicity (CC50 between 69 and 100 μM). These findings suggest that pyrazole-nitroimidazole derivatives represent a promising heterocyclic system, serving as a potential lead for further optimization in trichomoniasis chemotherapy.

Positive cases of bovine genital campylobacteriosis and bovine trichomonosis in the eradication program of La Pampa, Argentina: 2008-2021

Bovine genital campylobacteriosis, caused by the gram-negative bacteria Campylobacter fetus venerealis, and bovine trichomonosis, caused by the parasite protozoan Tritrichomonas foetus, are venereal diseases that occur with long intercalving periods and abortion. The control of both diseases relies on microbiological testing and culling infected bulls. Vaccination and antibiotic treatment may help in controlling campylobacteriosis but are not recommended for trichomonosis control. Several regions of the world have active control programs for trichomonosis, not campylobacteriosis. In Argentina, the state of La Pampa aims to eradicate trichomonosis and campylobacteriosis by imposing annual diagnostic testing of every bull and slaughtering positive animals. Prior studies indicated a declining trend in the prevalence of campylobacteriosis and trichomonosis in La Pampa. It was also proposed that the prevalence of one disease could be estimated from the prevalence of the other. The purpose of this retrospective analysis of data gathered from 2008 to 2021 was to determine the La Pampa program's efficacy. Descriptive statistics were employed to determine the reason behind the correlation between tricomonosis and campylobacteriosis diagnostic results. The outcomes refute the notion that this program of venereal eradication was a success. Furthermore, an excess of false positives in both diagnoses may have contributed to the correlation between the prevalences of campylobactriosis and trichomonosis. The practice of killing animals without verifying positive results hinders the determination of disease prevalence and results in the death of numerous healthy animals.

Infectious vaginitis among women seeking reproductive health services at a sexual and reproductive health facility in Kampala, Uganda

BACKGROUND

Infectious vaginitis is one of the most prevalent conditions affecting women of reproductive age with significant clinical consequences. Bacterial vaginosis (BV), vulvo-vaginal candidiasis (VVC), and trichomoniasis (TV) are the main etiologies. Unfortunately, there is limited data on the prevalence and associated risk factors, especially in sub-saharan Africa. This study, thus, determined the prevalence and risk factors of infectious vaginitis among women seeking reproductive health services at a Marie-stopes health facility in urban areas of Kampala, Uganda.

METHODS

A cross-sectional study with 361 participants was conducted from July to October 2021. Data on risk factors and infection were collected via a structured questionnaire and laboratory analysis of vaginal swabs, respectively, with data analysis performed using Stata version 14.0 college station, Texas 77,845 US.

RESULTS

The ages of participants ranged from 18 to 49 years, with a mean age of 29.53 years. Overall, 58.45% were infected, of whom 33.24% had VVC, 24.93% had BV, and 0.28% had TV. Bivariate analysis revealed that women with pruritus (COR: 3.057, 95% CI: 1.940-4.819), pregnancy (COR: 4.914, 95% CI: 1.248-19.36), antibiotic use (COR: 1.592, 95% CI: 1.016-2.494), douching (COR: 1.719, 95% CI: 1.079-2.740), and multiple partners (COR: 1.844, 95% CI: 1.079-2.904) were more likely to have VVC, whereas having higher education status (University; Vocational) (COR: 0.325, 95% CI: 0.134-0.890; COR: 0.345, 95% CI: 0.116-0.905) reduced the risk. On the other hand, women with a smelly discharge (COR: 1.796, 95% CI: 1.036-3.110), IUD use (COR: 1.868, 95% CI: 1.039-3.358), and antibiotic use (COR: 1.731, 95% CI: 1.066-2.811) were more likely to have BV. Multivariable analysis identified pruritus (AOR: 2.861, 95% CI: 1.684-4.863) as the only independent predictor for VVC.

CONCLUSION

Results indicate a high prevalence of infection among these women; therefore regular screening and treatment is recommended to curb the high rate of infection. More studies on risk factors of infection are recommended.

Phenolic chalcones as agents against Trichomonas vaginalis

Trichomonas vaginalis, a flagellated and anaerobic protozoan, is a causative agent of trichomoniasis. This disease is among the world's most common non-viral sexually transmitted infection. A single class drug, nitroimidazoles, is currently available for the trichomoniasis treatment. However, resistant isolates have been identified from unsuccessfully treated patients. Thus, there is a great challenge for a discovery of innovative anti-T. vaginalis agents. As part of our ongoing search for antiprotozoal chalcones, we designed and synthesized a series of 21 phenolic chalcones, which were evaluated against T. vaginalis trophozoites. Structure-activity relationship indicated hydroxyl group plays a role key in antiprotozoal activity. 4'-Hydroxychalcone (4HC) was the most active compound (IC50 = 27.5 µM) and selected for detailed bioassays. In vitro and in vivo evaluations demonstrated 4HC was not toxic against human erythrocytes and Galleria mellonella larvae. Trophozoites of T. vaginalis were treated with 4HC and did not present significant reactive oxygen species (ROS) accumulation. However, compound 4HC was able to increase ROS accumulation in neutrophils coincubated with T. vaginalis. qRT-PCR Experiments indicated that 4HC did not affect the expression of pyruvate:ferredoxin oxidoreductase (PFOR) and β-tubulin genes. In silico simulations, using purine nucleoside phosphorylase of T. vaginalis (TvPNP), corroborated 4HC as a promising ligand. Compound 4HC was able to establish interactions with residues D21, G20, M180, R28, R87 and T90 through hydrophobic interactions, π-donor hydrogen bond and hydrogen bonds. Altogether, these results open new avenues for phenolic chalcones to combat trichomoniasis, a parasitic neglected infection.

Effects of SQ109 on Trichomonas vaginalis

Trichomonas vaginalis is a protozoan that causes human trichomoniasis, a sexually transmitted infection (STI) that affects approximately 278 million people worldwide. The current treatment for human trichomoniasis is based on 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole, known as Metronidazole (MTZ). Although effective in eliminating parasitic infection, MTZ is related to serious adverse effects and is not recommended during pregnancy. In addition, some strains are resistant to 5'-nitroimidazoles, prompting the development of alternative drugs for trichomoniasis. Here we show that SQ109 [N-adamantan-2-yl-N'-((E)-3,7-dimethyl-octa- 2,6-dienyl)-ethane-1,2-diamine], a drug under development (antitubercular drug candidate that completed Phase IIb/III) for the treatment of tuberculosis, and previously tested in Trypanosoma cruzi and Leishmania. SQ109 inhibited T.vaginalis growth with an IC50 of 3.15 μM. We used scanning and transmission electron microscopy to visualize the ultrastructural alterations induced by SQ109. The microscopy analysis showed morphological changes on the protozoan surface, where the cells became rounded with increasing surface projections. In addition, the hydrogenosomes increased their size and area occupied in the cell. Furthermore, the volume and a significant association of glycogen particles with the organelle were seen to be altered. A bioinformatics search was done about the compound to find its possible targets and mechanisms of action. Our observations identify SQ109 as a promising compound against T. vaginalis in vitro, suggesting its potential utility as an alternative chemotherapy for trichomoniasis.

Identification of volatile biomarkers of Trichomonas vaginalis infection in vaginal discharge and urine

Trichomoniasis, a disease caused by Trichomonas vaginalis, is the most common non-viral sexually transmitted infection worldwide. The importance of its diagnosis lies in its ease of transmission and the absence of symptoms in most cases, as occurs in men, which have a significant role as asymptomatic carriers. The most widely used diagnostic methods are the fresh examination of vaginal or urethral secretions and molecular techniques. However, as they have some disadvantages and, sometimes, low sensitivity, new trichomoniasis diagnostic methods are necessary. Volatile organic compounds in clinical samples are effective in the diagnosis of different diseases. This work aimed to study, for the first time, those present in vaginal discharge and urine of patients with Trichomonas vaginalis infection to look for volatile biomarkers. The results showed that volatile compounds such as 2-methyl-1-propanol and cyclohexanone could serve as biomarkers in vaginal discharge samples, as well as 2-octen-1-ol and 3-nonanone in urine. Moreover, 3-hydroxy-2,4,4-trimethylpentyl 2-methylpropanoate found in vaginal discharge, highly correlated to positive patients, is also highly related to urines of patients with trichomoniasis. The biomarkers described in this study might be a promising diagnostic tool. KEY POINTS: • The incidence of Trichomonas vaginalis infection is increasing • Trichomonas vaginalis VOC study in vaginal discharge and urine was performed • The identification of volatile biomarkers could allow a new diagnostic method.

Anti-Trichomonas vaginalis activity of essential oils extracted from Caatinga Myrtaceae species and chemical composition of Eugenia pohliana DC

The current trichomoniasis treatment is restrict to 5-nitroimidazole drugs and the emergence of resistant isolates points the need for new therapeutical alternatives. In this study the anti-Trichomonas vaginalis activity of essential oils obtained from Myrtaceae occurring in Caatinga, a plant family with potential antiparasitic activity, was showed. The essential oils varied in their capacity to kill ATCC and fresh clinical T. vaginalis isolates, which was associated with heterogeneity and different patterns of endosymbiosis. Essential oils caused moderate to strong cytotoxicity against mammalian cells, but essential oil of Eugenia pohliana (EOEp) exhibited promising selectivity index towards vaginal epithelial cells. A checkerboard assay revealed a synergistic effect when EOEp and metronidazole were associated, indicating different mechanisms of action. The GC/MS analysis demonstrated the volatile composition of EOEp, with δ-cadinene as majoritary component. This molecule seems to contribute to the trichomonacidal effect and shows potential for the prospection of new antiparasitic compounds.

Infectious Vaginitis, Cervicitis, and Pelvic Inflammatory Disease

Vaginal symptoms are one of the most common reasons women consult with physicians and can significantly impact quality of life. The differential diagnosis of vaginal discharge includes physiologic discharge, vaginitis, cervicitis, and pelvic inflammatory disease (PID). Vaginitis is inflammation of the vagina, most commonly caused by bacterial vaginosis (BV), vulvovaginal candidiasis, and trichomoniasis infections. Cervicitis is an inflammation of the cervix and typically caused by Chlamydia trachomatis and Neisseria gonorrhoeae. PID is infection of the female upper genital tract, involving the uterus, fallopian tubes, ovaries, and/or pelvic peritoneum and usually caused by Chlamydia trachomatis, Neisseria gonorrhoeae, and bacterial vaginosis-associated pathogens. A pelvic exam should be performed for any woman presenting with vaginal discharge to confirm the diagnosis and rule out an upper tract infection. BV and vulvovaginal candidal infections only require treatment if symptomatic and do not require partner therapy, whereas treatment and partner therapy is recommended for sexually transmitted illnesses, such as trichomoniasis, chlamydia and gonorrhea. Vaginitis may be uncomfortable, but rarely leads to serious long-term consequence, but pelvic inflammatory disease can lead to serious long-term sequelae, including increased risk for ectopic pregnancy, infertility, and chronic pelvic pain.

Molecular diagnosis of Trichomonas vaginalis in liquid-based Papanicolaou samples in Shiraz, southern Iran

BACKGROUND

Trichomoniasis is a parasitic infection of the urinary and genital tract, caused by Trichomonas vaginalis. This study aimed to investigate the molecular diagnosis of T. vaginalis infection in liquid-based Papanicolaou samples in Shiraz, southern Iran.

MATERIALS AND METHODS

In this cross-sectional study, 534 liquid-based Papanicolaou samples were collected from women referring to the laboratory of Motahari Clinic of Shiraz University of Medical Sciences in 2021. Genomic DNA were extracted from the samples and examined for evidence of T. vaginalis using polymerase chain reaction (PCR) using TVK3 and TVK7 specific primers.

RESULTS

The mean age of participants was 39.28 ± 9.89 with a maximum age of 65 and a minimum age of 19 years. T. vaginalis DNA fragments were detected in 4.86% (26/534) of the cases. There was significantly higher prevalence in the age groups of 21 to 30 and 41 to 50 years (46.15%, p = 0.001 and 38.46%, p = 0.015, respectively). Furthermore, the results showed an association between a history of foamy discharge and Trichomonas positivity (p = 0.001).

CONCLUSION

T. vaginalis infection is common in liquid-based Papanicolaou samples of women who attended regular health check-ups in the study area. Screening for trichomoniasis in populations, particularly if using highly sensitive methods such as PCR, may lead to increased detection and treatment.

Trichomoniasis refractory to 5-nitroimidazole therapy in Trinidad

Trichomoniasis is the most common non-viral sexually transmitted infection (STI) occurring worldwide and the majority of infected persons (70-85%) have mild or no genital symptoms. Symptoms in women may include a vaginal discharge which may be associated with vulval irritation and most infections can be effectively treated with metronidazole 500mg bd for seven days. Trichomoniasis unresponsive to 5-nitroimidazole therapy is uncommon but results in substantial therapeutic challenges, especially in resource limited countries. We present such a case which was eventually treated with a low-cost intravaginal combination of boric acid and clotrimazole cream.

Secnidazole: a treatment for trichomoniasis in adolescents and adults

INTRODUCTION

Single-dose 2-g oral secnidazole (SEC), newly approved by the U.S. Food and Drug administration (FDA) for treatment of trichomoniasis, is a potent 5-nitroimidazole with selective toxicity against various micro-organisms. It has been used internationally to treat trichomoniasis, bacterial vaginosis, and other infections for decades. Trichomoniasis is the most common non-viral sexually transmitted infection worldwide and is associated with significant morbidity. In comparison to the only other FDA-approved treatments for trichomoniasis in the United States - metronidazole and tinidazole - SEC has favorable pharmacokinetics, including a longer half-life and a lower minimal lethal concentration.

AREAS COVERED

This work summarizes the chemistry and pharmacology of SEC and reviews the evidence on its efficacy, tolerability, and safety for the treatment of trichomoniasis.

EXPERT OPINION

SEC is an efficacious, well tolerated, and safe treatment for patients aged ≥12 years with trichomoniasis. Single-dose administration makes it a favorable treatment option, especially in cases where adherence to multi-dose treatment regimens may be low.

In vitro activity of amixicile against T. vaginalis from clinical isolates

Trichomoniasis is a sexually transmitted infection in humans caused by the protozoan Trichomonas vaginalis, the leading causative agent of vaginitis in women and urethritis in men worldwide. Metronidazole is the standard treatment for trichomoniasis, with tinidazole as the second line. There are currently no FDA-approved non-nitroimidazole alternative treatments for resistant strains. This study compares the efficacy of a newly synthesized non-nitroimidazole oral drug, amixicile, to that of both metronidazole and the synthetic precursor of amixicile, nitazoxanide with in vitro sensitivity testing. One standard strain from ATCC and three patient-isolated strains of T. vaginalis were used to compare treatments under anaerobic conditions. The minimum inhibitory concentration for metronidazole, nitazoxanide, and amixicile were 12.5 μM, 100 μM, and 6.25 μM, respectively. These results suggest that amixicile may be highly active against T. vaginalis and warrants further investigation as a potential alternative to metronidazole in the treatment of trichomoniasis.

Increasing incidence rates of sexually transmitted infections from 2010 to 2019: an analysis of temporal trends by geographical regions and age groups from the 2019 Global Burden of Disease Study

Background

World Health Organization announced its goal of ending sexually transmitted infection (STI) epidemics by 2030. To provide a reference for tailored prevention strategies, we analyzed trends and differences in STIs by geographical regions and age groups from 1990 to 2019.

Methods

Annual number of new infections and age-standardized incidence rates (ASRs) of syphilis, chlamydia, gonorrhea, trichomoniasis, and genital herpes were recorded from the 2019 Global Burden of Disease study. We quantified the temporal trends of STIs by calculating changes in new infections and estimated annual percentage changes (EAPCs) of ASR.

Results

The ASRs of syphilis, chlamydia, trichomoniasis, and genital herpes increased by 1.70% (95% confidence interval [CI], 1.62–1.78%), 0.29% (95% CI 0.04–0.54%), 0.27% (95% CI 0.03–0.52%), and 0.40% (95% CI 0.36–0.44%) per year from 2010 to 2019 worldwide, respectively, while that of gonorrhea did not. The American regions had the greatest increase in ASR for syphilis (tropical Latin America: EAPC, 5.72; 95% CI 5.11–6.33), chlamydia (high-income North America: EAPC, 1.23; 95% CI 0.73–1.73), and gonorrhea (high-income North America: EAPC, 0.77; 95% CI 0.12–1.41). Additionally, southern sub-Saharan Africa and East Asia had the greatest increase in ASR for trichomoniasis (EAPC, 0.88; 95% CI 0.57–1.20) and genital herpes (EAPC, 1.44; 95% CI 0.83–2.06), respectively. In the most recent years, the population with the greatest incidence of syphilis tended to be younger globally (25–29 years in 2010 vs. 20–24 years in 2019) but older in North Africa and Middle East (20–24 year vs. 25–29 years); with chlamydia tended to be older in southern sub-Saharan Africa (25–29 years vs. 30–34 years) but younger in Australasia (40–44 years vs. 25–29 years); with genital herpes tended to be older in high-income North America (20–24 years vs. 25–29 years) and South Asia (25–29 years vs. 30–34 years).

Conclusions

Syphilis, chlamydia, trichomoniasis, and genital herpes showed a trend of increasing ASR from 2010 to 2019. The differences in trends by geographical regions and age groups point to the need for more targeted prevention strategies in key regions and populations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07544-7.

Local cytokine/chemokine profiles in BALB/c and C57BL/6 mice in response to T. vaginalis infection

Trichomonas vaginalis is the causative agent of Trichomoniasis (a sexually transmitted infection). Recent reports have shown that stimulation of cellular immunity can reduce trichomoniasis infection. Animal studies are essential to understanding the pathogenesis of infection and developing new potential drugs and vaccines to treat the infection. Therefore, we have tried to understand the pathogenesis of T. vaginalis infection by investigating the differences in the expression of chemokine/cytokine levels in vaginal and cervical tissues of BALB/c and C57BL/6 mice. Different pathological symptoms, like desquamation, neutrophil infiltration, and hemorrhage, were recorded in BALB/c and C57BL/6 in response to T. vaginalis infection. Vaginal and cervical tissues of BALB/c showed these symptoms on 2nd dpi, which became severe on 7th dpi and turned to mild or normal till 14th dpi compared to C57BL/6 strain. Immunohistochemistry in the vagina and cervical tissues of BALB/c and C57BL/6 mice was done to assess cytokines at different time intervals post-infection. Significant expression of Interleukin-1β (IL-1β) (a pro-inflammatory cytokine) was found in BALB/c compared to the C57BL/6 mice, on 7th dpi and 2nd dpi in vaginal and cervical tissues, respectively. Higher expression of MIP-2 (neutrophil chemoattractant) was observed in the vaginal tissues of BALB/c mice on 7th dpi compared to the C57BL/6 group. In addition, higher expression of TGF-β (immune-suppressor) was observed on 7th dpi in the vaginal tissue of BALB/c mice. The present study demonstrates that more pathological signs of T. vaginalis infection developed in BALB/c mice than C57BL/6 mice. Also, significant levels of IL-1β and MIP-2 were measured in BALB/c mice in response to T. vaginalis compared to C57BL/6.

Trichomonas infection in pregnant women: a nationwide cohort study

Trichomoniasis is the most prevalent sexually transmitted infection worldwide, and is associated with adverse pregnancy outcomes. However, Trichomonas vaginalis (TV) has received little public health attention, and only limited data are available on prevalence of TV and other Trichomonas-associated syndromes in pregnant women. This study aimed to determine associations between pregnancy and incident trichomoniasis-related diseases. Data of pregnant women were extracted from the National Health Insurance Research Database (NHIRD) of Taiwan. The pregnant cohort included 113,781 women, and cases were randomly matched by age, and index year with those of non-pregnant women (n = 113,781). Risk of incident trichomoniasis-related diseases was also not significantly different between pregnant and non-pregnant women. However, after stratifying by age or level of care, the younger subgroup among pregnant women had a higher risk of incident trichomoniasis-related diseases than did the younger subgroup in non-pregnant women, while the elder subgroup among pregnant women had a lower risk of incident trichomoniasis-related diseases than did the same subgroup in non-pregnant women (all p < 0.05). The higher level of care (medical center) subgroup among pregnant women had a lower risk of incident trichomoniasis-related diseases than did the same subgroup in non-pregnant women. In conclusions, although pregnancy is not significantly associated with risk of trichomoniasis-related diseases, data of the present study support an enhanced high level of medical care for pregnant women, emphasizing the potential of high medical care in reduced incidence of trichomoniasis-related diseases. This may be an effective strategy for reducing various pregnancy complications associated with trichomoniasis-related diseases.

Secnidazole for Trichomoniasis in Women and Men

INTRODUCTION

Secnidazole (SEC), newly FDA-approved for trichomoniasis, is a potent 5-nitroimidazole with selective toxicity against various infections. It has been used internationally to treat trichomoniasis, bacterial vaginosis, and other infections for decades. Trichomoniasis is the most common non-viral sexually transmitted infection worldwide and is associated with significant morbidity. In comparison to the only other approved treatments for trichomoniasis in the U.S.-metronidazole and tinidazole-SEC has favorable pharmacokinetics, including a longer half-life, and a lower minimal lethal concentration against Trichomonas vaginalis.

OBJECTIVES

Provide an updated, comprehensive review of the literature evaluating SEC as a treatment for trichomoniasis in women and men.

METHODS

We conducted a search to identify existing research on SEC and trichomoniasis. On August 6, 2021, we searched MEDLINE using the terms "secnidazole" and "trichomon.*" We excluded reviews, editorials, case reports, and small case series.

RESULTS

We identified 29 articles; 14 of which were included: 5 reported in vitro pharmacologic data on SEC, 6 were observational studies, and 4 were controlled clinical trials (1 observational study also reported in vitro pharmacologic data). Six studies reported data on women only, 1 on men only, and 3 on women and men. These studies showed that SEC-as a single dose or 3-day course-had comparable efficacy to multi-dose metronidazole for treating trichomoniasis in women and men, was generally well tolerated by patients, and had a favorable pharmacokinetic profile. A single 2-g dose of SEC also led to a microbiologic cure rate of 92.2% in the first randomized, double-blind, placebo-controlled study of trichomonas-infected US-based women.

CONCLUSION

SEC is an efficacious and safe treatment for women and men with trichomoniasis. Single-dose administration makes it a favorable treatment option for patients, especially in cases where adherence to other multi-dose treatment regimens could be problematic. Christina A. Muzny and Olivia T. Van Gerwen. Secnidazole for Trichomoniasis in Women and Men. Sex Med Rev 2022;10:255-262.

Anti-Trichomonas vaginalis activity and chemical analysis of metabolites produced by marine-associated fungi

Trichomoniasis is the most common non-viral sexually transmitted infection worldwide and it may have serious consequences, especially for women. Currently, 5-nitroimidazole drugs are the treatment of choice for trichomoniasis, although presenting adverse effects and reported cases of drug resistance. Metabolites isolated from marine fungi have attracted considerable attention due to their unique chemical structures with diverse biological activities, including antiprotozoal activity. In this study, we showed the anti-Trichomonas vaginalis activity of fractions obtained from marine fungi and the chemical composition of the most active fraction was determined. Ethyl acetate fractions of the fungus Aspergillus niger (EAE03) and Trichoderma harzianum/Hypocrea lixii complex (EAE09) were active against T. vaginalis. These samples, EAE03 and EAE09, were also effective against the fresh clinical isolate metronidazole-resistant TV-LACM2R, presenting MIC values of 2.0 mg/mL and 1.0 mg/mL, respectively. The same MIC values were found against ATCC 30,236 T. vaginalis isolate. In vitro cytotoxicity revealed only the fraction named EAE03 with no cytotoxic effect; however, the active fractions did not promote a significant hemolytic effect after 1-h incubation. Already, the in vivo toxicity evaluation using Galleria mellonella larvae demonstrated that none of the tested samples caused a reduction in animal survival. The fraction EAE03 was followed for purification steps and analyzed by LC-DAD-MS. Eleven compounds were annotated, including butyrolactone, butanolide, and atromentin. Overall, the range of activities reported confirms the potential of marine fungi to produce bioactive molecules.

A review of its incidence, research prioritization, and the resulting health disparities

Structural racism plays a significant role in limited access to higher education, financial resources, employment opportunities, and high-quality healthcare for African Americans. The lack of healthcare equity and infrastructure has directly contributed to overall poor healthcare outcomes for the Black community. Studies have shown that adverse health outcomes such as sexually transmitted diseases (STDs) are more prevalent in African Americans, regardless of their socioeconomic factors and lifestyles. For example, trichomoniasis, transmitted sexually by its etiological agent, Trichomonas vaginalis (T. vaginalis), predisposes those infected to co-infections with other STDs, such as human immunodeficiency virus (HIV), herpes, and other related infections. Our review showcases the impact of trichomoniasis on the health of the Black community with an emphasis on African American women. A critical examination of the socio-demographic history of Black people in the United States (US) is vital to illustrate the origin of past and current racial health disparities. Further, we expand the complex and nuanced conversation on the intersectionality of racism, health equity, and innovative epidemiological and biomedical research strategies needed to eradicate this global public health threat.

Antimicrobial properties of tomato leaves, stems, and fruit and their relationship to chemical composition

BACKGROUND

We previously reported that the tomato glycoalkaloid tomatine inhibited the growth of Trichomonas vaginalis strain G3, Tritrichomonas foetus strain D1, and Tritrichomonas foetus-like strain C1 that cause disease in humans and farm and domesticated animals. The increasing prevalence of antibiotic resistance requires development of new tools to enhance or replace medicinal antibiotics.

METHODS

Wild tomato plants were harvested and divided into leaves, stems, and fruit of different colors: green, yellow, and red. Samples were freeze dried and ground with a handheld mill. The resulting powders were evaluated for their potential anti-microbial effects on protozoan parasites, bacteria, and fungi. A concentration of 0.02% (w/v) was used for the inhibition of protozoan parasites. A high concentration of 10% (w/v) solution was tested for bacteria and fungi as an initial screen to evaluate potential anti-microbial activity and results using this high concentration limits its clinical relevance.

RESULTS

Natural powders derived from various parts of tomato plants were all effective in inhibiting the growth of the three trichomonads to varying degrees. Test samples from leaves, stems, and immature 'green' tomato peels and fruit, all containing tomatine, were more effective as an inhibitor of the D1 strain than those prepared from yellow and red tomato peels which lack tomatine. Chlorogenic acid and quercetin glycosides were present in all parts of the plant and fruit, while caffeic acid was only found in the fruit peels. Any correlation between plant components and inhibition of the G3 and C1 strains was not apparent, although all the powders were variably effective. Tomato leaf was the most effective powder in all strains, and was also the highest in tomatine. S. enterica showed a minor susceptibility while B. cereus and C. albicans fungi both showed a significant growth inhibition with some of the test powders. The powders inhibited growth of the pathogens without affecting beneficial lactobacilli found in the normal flora of the vagina.

CONCLUSIONS

The results suggest that powders prepared from tomato leaves, stems, and green tomato peels and to a lesser extent from peels from yellow and red tomatoes offer potential multiple health benefits against infections caused by pathogenic protozoa, bacteria, and fungi, without affecting beneficial lactobacilli that also reside in the normal flora of the vagina.

Antitrichomonal activity of metronidazole-loaded lactoferrin nanoparticles in pigeon trichomoniasis

In recent years, increasing attention has been paid to the novel drug delivery systems to reduce the dose of the drug and avoid side effects. Metronidazole has been used for many years in the treatment of anaerobic bacterial and protozoal infections. Nanolactoferrin, a newly developed antibacterial agent originated from lactoferrin, is applied both as an active therapeutic and a drug nanocarrier. The present study describes the development and characterization of metronidazole-loaded lactoferrin nanoparticles (nano-MTZ) as well as reports their antitrichomonal activity on Trichomonas gallinae, the protozoal causative agent of pigeon trichomoniasis. The activity of the nano-MTZ is compared with the regular metronidazole formulation (MTZ) under in vitro and in vivo conditions. Additionally, cytotoxicity of the nano-MTZ to fibroblast cell line and possible hepatotoxicity in treated pigeons were evaluated. Nano-MTZ was prepared based on the thermal treatment method and the average size and surface charge of the dispersion were 30.6 nm and - 44.6 mv, respectively. No significant cytotoxicity was noted for the nano-MTZ in comparison to the MTZ. Loading efficiency in nano-MTZ was calculated as 55%. In vitro susceptibility results demonstrated 24 h 90% lethal concentration values of 4.23 and 6.64 µg/mL for MTZ and nano-MTZ, respectively. Oral treatment of the pigeons experimentally infected with T. gallinae resulted in the earlier eradication of the infection in the nano-MTZ-treated pigeons. No adverse effects on the liver function have been observed for the nano-MTZ. These findings suggest that nanolactoferrin is a promising platform for the development of novel MTZ formulations with improved antitrichomonal activity.

Vaginal leukocyte counts for predicting sexually transmitted infections in the emergency department

BACKGROUND

The use of vaginal white blood cell (WBC) counts to predict sexually transmitted infections (STIs) in the emergency department (ED) is incompletely characterized.

OBJECTIVES

Our objective was to assess the relationship between vaginal wet preparation WBC counts and STIs and to determine whether WBC counts of at least 11 WBCs per high-power field (HPF) could be useful for identifying STIs in women in the ED.

METHODS

Female ED patients 18 years or older who were evaluated in a single health system between April 18, 2014, and March 7, 2017, and had a genital wet preparation WBC result were retrospectively examined using univariable and multivariable analysis.

RESULTS

Vaginal wet preparation WBC counts were examined for 17,180 patient encounters. Vaginal WBC counts of at least 11 WBCs/HPF were associated with increased odds of having gonorrhea, chlamydia, or trichomoniasis. When this threshold was used for the diagnosis of each STI, sensitivity ranged from 48.2% to 53.9%, and specificity ranged from 67.2% to 68.8%.

CONCLUSION

Women with STIs are more likely to have higher vaginal WBC counts. However, higher vaginal wet preparation WBC counts in isolation have limited diagnostic utility for gonorrhea, chlamydia, and trichomoniasis. Incorporation of age, urine leukocyte esterase results, and vaginal WBC counts provided a better predictor of an STI than vaginal WBC counts alone.

Global prevalence of Trichomonas vaginalis among female sex workers: a systematic review and meta-analysis

Trichomoniasis is a sexually transmitted infection (STI), caused by the protozoan parasite, Trichomonas vaginalis. Female sex workers are intensely affected by the infection, since they have frequent direct physical contact. The current systematic review and meta-analysis represents the global prevalence of T. vaginalis in female sex workers. Five databases (Science Direct, Scopus, PubMed, Web of Science, and Google Scholar) were explored for literatures that published from July 1985 to June 2020. Totally, 85 studies (54,515 participants) from 46 countries met the inclusion criteria. The global pooled prevalence of T. vaginalis was 16% (95% CI 13-19%). The estimated pooled prevalence based on methods including wet mount, culture, and molecular techniques was 15% (95% CI 12-19%), 16% (95% CI 10-24%), and 22% (95% CI 13-32%), respectively. Moreover, the infection was most prevalent at the mean age of 30-36 (20%, 95% CI 11-30%). Regarding the World Health Organization (WHO) regions, the highest pooled prevalence was estimated to be in the African region (23%, 95% CI 7-46%). In addition, we indicated that countries with low-income level have the highest pooled prevalence (23%, 95% CI 14-34%). Our results revealed that the worldwide prevalence of T. vaginalis was significant in female sex workers. Therefore, considering a precise strategy such as a health education program with regard to safe intercourse is needed to increase knowledge and prevent T. vaginalis infection in sex workers.

Epidemiology, natural history, diagnosis, and treatment of Trichomonas vaginalis in men

Trichomonas vaginalis infections in men are traditionally considered to be benign and consequently have been overlooked. However, men with this common sexually transmitted infection can experience urethritis, prostatitis, reduced fertility, and amplified HIV risk. In addition, men are often asymptomatic and can unknowingly spread the infection to their female sexual partners. With advances in T. vaginalis diagnostics, more men are being diagnosed, yet the optimal method of treatment in men remains unknown. The purpose of this review is to discuss the epidemiology, natural history, diagnosis, and treatment of T. vaginalis among men.

Comparative pharmacokinetics of metronidazole in healthy and Trichomonas gallinae infected pigeons (Columba livia, var. domestica)

1. This study investigated the pharmacokinetics of metronidazole after intravenous (i.v.) and oral administration to healthy and experimentally Trichomonas gallinae-infected pigeons, and determined the in vitro antiprotozoal activity of metronidazole against T. gallinae.2. Twelve pigeons which were experimentally infected to T. gallinae and twelve healthy pigeons received metronidazole at the dose of 25 mg/kg by oral or i.v. administration. Serial blood sampling was used for pharmacokinetic analysis. The metronidazole minimum lethal concentration (MLC) and the concentration killing 50% of the trophozoites (LC₅₀) in the culture media were determined.3. In vitro data showed that the 24 h LC₅₀ and MLC of metronidazole were 0.31 and 25 µg/ml, respectively. In vivo results showed no statistical differences between pharmacokinetics in infected and non-infected pigeons for both routes of administration. The area under the curve was statistically higher after the i.v. administration in both infected and healthy pigeons. The mean oral bioavailability was similar in the infected (83.8%) and the healthy (81.5%) birds.4. In conclusion, the pharmacokinetics of metronidazole in pigeons was not affected by experimentally-induced trichomoniasis. Despite in vitro susceptibility testing, which showed probable resistance of the isolated T. gallinae to metronidazole, five-day oral treatment of infected pigeons with 25 mg/kg metronidazole twice a day resulted in total eradication of trophozoites recovered in crop lavage of infected birds.

Photo-genosensor for Trichomonas vaginalis based on gold nanoparticles-genomic DNA

Trichomoniasis, an infectious disease caused by a parasite called Trichomonas vaginalis (T. vaginalis), enhances the risk of HIV infection, cervical and prostate cancer, and infertility. Therefore, efforts have to be made for accurate, specific, and rapid diagnosise and treatment of trichomoniasis. Today, optical nanosensors have created an opportunity for diagnosis without sophisticated and expensive tools and the need for expertise; at the same time, they are highly sensitive and fast. An optical nano-genosensor was designed by conjugation of gold nanoparticles and a specific oligonucleotide (AuNPs-probe) from repeated DNA target for specific and sensitive polymerase chain reaction diagnosis of T. vaginalis gene sequence (L23861.1). The hybridization of AuNPs-probe was investigated with different concentrations of complementary sequence in synthesized target, gene sequence of standard T. vaginalis genomic DNA extraction, and PCR products of genomic DNA samples extracted from patients. Negative samples including synthesized non-complementary sequence, genomics DNA of other pathogens, and genomics DNA of healthy persons were considered for proof of the accuracy of the sensor function. The occurrence of correct hybridization was detected by adding acid to the medium and observing the changes in the color of the medium and spectroscopic spectrum. Based on spectrophotometric results, the fabricated genosensor had detection limits of 35.16 and 31 pg μL^-1 for the detection of synthetic target and genomic DNA sequences, respectively. The results confirmed the correct function of genosensor for the detection of T. vaginalis in clinical samples. Advantages such as low cost, visual detection, speed, and easy diagnosis encourage the use of this sensor in pathogen detection in the future.

A review study on the anti-trichomonas activities of medicinal plants

The parasitic diseases represent the most important health risk, especially in underdeveloped countries where they have a deep impact on public health. Trichomoniasis is a prevalent non-viral sexually transmitted disease, and a significant amount of new cases are identified each year globally. Furthermore, the infection is linked with serious concerns such as pregnancy outcomes, infertility, predisposition to cervical and prostate cancer, and increased transmission and acquisition of HIV. The therapy is restricted, adverse effects are often observed, and resistance to the drugs is emerging. Based on this, a new treatment for trichomoniasis is necessary. Natural products represent a rich source of bioactive compounds, and even today, they are used in the search for new drugs. Additionally, natural products provide a wide variety of leadership structures that can be used by the pharmaceutical industry as a template in the development of new drugs that are more effective and have fewer or no undesirable side effects compared to current treatments. This review focuses on the medicinal plants that possess anti-trichomonal activity in vitro or in vivo. An electronic database search was carried out covering the last three decades, i.e., 1990-2020. The literature search revealed that almost a dozen isolated phytoconstituents are being explored globally for their anti-trichomonal activity. Simultaneously, many countries have their own traditional or folk medicine for trichomoniasis that utilizes their native plants, as a whole, or even extracts. This review focuses mainly on the human parasite Trichomonas vaginalis. However, at some points mention is also made to Tritrichomonas foetus that causes trichomoniasis in animals of high veterinary and economical interest. We will focus on the plants and plant-based compounds and their anti-trichomonal activity. The literature search highlighted that there are abundant compounds that possess anti-trichomonal activity; however, in-depth in-vivo evaluation of compounds and their clinical evaluation has not been undertaken. There is a critical need for new anti-trichomonal compounds, and focused research on phytoconstituents can provide the way forward.

Chitosan-based systems aimed at local application for vaginal infections

Vaginal administration is a promising route for the local treatment of infectious vaginal diseases since it can bypass the first-pass metabolism, drug interactions, and adverse effects. However, the commercial products currently available for topical vulvovaginal treatment have low acceptability and do not adequately explore this route. Mucoadhesive systems can optimize the efficacy of drugs administered by this route to increase the retention time of the drug in the vaginal environment. Several polymers are used to develop mucoadhesive systems, among them chitosan, a natural polymer that is highly biocompatible and technologically versatile. Thus, the present review aimed to analyze the studies that used chitosan to develop mucoadhesive systems for the treatment of local vaginal infections. These studies demonstrated that chitosan as a component of mucoadhesive drug delivery systems (DDS) is a promising device for the treatment of vaginal infectious diseases, due to the intrinsic antimicrobial activity of this biopolymer and because it does not interfere with the effectiveness of the drugs used for the treatment.

Global survey of miRNAs and tRNA-derived small RNAs from the human parasitic protist Trichomonas vaginalis

BACKGROUND

Small non-coding RNAs play critical regulatory roles in post-transcription. However, their characteristics in Trichomonas vaginalis, the causative agent of human sexually transmitted trichomoniasis, still remain to be determined.

METHODS

Small RNA transcriptomes from Trichomonas trophozoites were deep sequenced using the Illumina NextSeq 500 system and comprehensively analyzed to identify Trichomonas microRNAs (miRNAs) and transfer RNA (tRNA)-derived small RNAs (tsRNAs). The tsRNA candidates were confirmed by stem-loop quantitative reverse transcription-PCR, and motifs to guide the cleavage of tsRNAs were predicted using the GLAM2 algorithm.

RESULTS

The miRNAs were found to be present in T. vaginalis but at an extremely low abundance (0.0046%). Three categories of endogenous Trichomonas tsRNAs were identified, namely 5'tritsRNAs, mid-tritsRNAs and 3'tritsRNAs, with the 5'tritsRNAs constituting the dominant category (67.63%) of tsRNAs. Interestingly, the cleavage site analysis verified both conventional classes of tRNA-derived fragments (tRFs) and tRNA-halves in tritsRNAs, indicating the expression of tRNA-halves in the non-stress condition. A total of 25 tritsRNAs were experimentally confirmed, accounting for 78.1% of all tested candidates. Three motifs were predicted to guide the production of tritsRNAs. The results prove the expression of tRFs and tRNA-halves in the T. vaginalis transcriptome.

CONCLUSIONS

This is the first report of genome-wide investigation of small RNAs, particularly tsRNAs and miRNAs, from Trichomonas parasites. Our findings demonstrate the expression profile of tsRNAs in T. vaginalis, while miRNA was barely detected. These results may promote further research aimed at gaining a better understanding of the evolution of small non-coding RNA in T. vaginalis and their functions in the pathogenesis of trichomoniasis.

Antitrichomonal activity and docking analysis of thiazole derivatives as TvMP50 protease inhibitors

Trichomoniasis, caused by the protozoan Trichomonas vaginalis, is the most prevalent non-viral sexually transmitted infection that affects over 170 million people worldwide. The only type of drug recommended for the therapeutic control of trichomoniasis is the 5-nitroimidazoles, although there have been reports of some undesirable side effects and clinical resistance. Hence, the need for the search for new tricomonicidal agents is necessary. In a previous work, we demonstrated that two 2-amino-4-aryl thiazole derivatives (ATZ-1 and ATZ-2) possess a portent antigiardial effect. In the current paper, we investigated the in vitro antitrichomonal activity of these thiazole compounds. Both ATZ-1 and ATZ-2 reduced the viability and growth of parasites in a dose-dependent manner, with an IC₅₀ value of 0.15 μg/mL and 0.18 μg/mL, respectively. Furthermore, both thiazole compounds were able to decrease the proteolytic activity in T. vaginalis trophozoites compared with untreated parasites. Interestingly, a full proteolytic inhibition profile was observed in the 50-kDa region which was associated with the decreased expression of the gene that codes for the trichomonad protease TvMP50. The docking simulations predicted strong interactions of the thiazole compounds in the TvMP50 protease's active site, suggesting a possible role as protease inhibitors. Our results demonstrate the potential of 2-amino-4-aryl thiazole derivatives as trichomonicidal compounds and could be, mechanistically, involved in the inhibition of key trichomonad proteases.

Inhibition of the newly discovered β‑carbonic anhydrase from the protozoan pathogen Trichomonas vaginalis with inorganic anions and small molecules

The protozoan pathogen Trichomonas vaginalis encodes two carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the β-class. One of these enzymes, T. vaginalis carbonic anhydrase 1 (TvaCA1), was recently cloned and characterized by our group, and its X-ray crystal structure reported. No inhibitors of this enzyme were reported up until now. Here we investigated the inhibition of TvaCA1 with inorganic anions and small molecules and observed that thiocyanate, cyanide, selenite, selenocyanate and divanadate are sub-millimolar inhibitors, whereas sulfamide, sulfate, phenylboronic acid and phenylarsonic acid are micromolar inhibitors. Finding effective TvaCA1 inhibitors may be useful for developing new antiprotozoan drugs.

Anti-trichomonad activities of different compounds from foods, marine products, and medicinal plants: a review

Human trichomoniasis, caused by the pathogenic parasitic protozoan Trichomonas vaginalis, is the most common non-viral sexually transmitted disease that contributes to reproductive morbidity in affected women and possibly to prostate cancer in men. Tritrichomonas foetus strains cause the disease trichomoniasis in farm animals (cattle, bulls, pigs) and diarrhea in domestic animals (cats and dogs). Because some T. vaginalis strains have become resistant to the widely used drug metronidazole, there is a need to develop alternative treatments, based on safe natural products that have the potential to replace and/or enhance the activity of lower doses of metronidazole. To help meet this need, this overview collates and interprets worldwide reported studies on the efficacy of structurally different classes of food, marine, and medicinal plant extracts and some of their bioactive pure compounds against T. vaginalis and T. foetus in vitro and in infected mice and women. Active food extracts include potato peels and their glycoalkaloids α-chaconine and α-solanine, caffeic and chlorogenic acids, and quercetin; the tomato glycoalkaloid α-tomatine; theaflavin-rich black tea extracts and bioactive theaflavins; plant essential oils and their compounds (+)-α-bisabolol and eugenol; the grape skin compound resveratrol; the kidney bean lectin, marine extracts from algae, seaweeds, and fungi and compounds that are derived from fungi; medicinal extracts and about 30 isolated pure compounds. Also covered are the inactivation of drug-resistant T. vaginalis and T. foetus strains by sensitized light; anti-trichomonad effects in mice and women; beneficial effects of probiotics in women; and mechanisms that govern cell death. The summarized findings will hopefully stimulate additional research, including molecular-mechanism-guided inactivations and human clinical studies, that will help ameliorate adverse effects of pathogenic protozoa.

Scientometric Analysis of Global Research on Trichomoniasis in Scopus Database (1922 -2018)

BACKGROUND

Trichomoniasis is a sexually transmitted disease (STD) prevalent in different parts of the world. The present study was designed to evaluate the scientific output and collaboration of researchers worldwide on trichomoniasis.

METHODS

In the present scientometric research, all papers conducted on Trichomonas vaginalis (T. vaginalis) published in the time period of 1922 to 2018 were extracted from the Scopus database and evaluated according to the aims of the research, using scientometric software.

RESULTS

The results of this search strategy were the retrieval of 12,596 scientific papers authored by a total of 28,822 people during 97 years (1922-2018). Research in this field has encountered success and failure over the years. The first article on trichomoniasis at the Scopus database was published by Musgrave W.E. (1922) in the "Journal of the American Medical Association". Most papers on this subject (352) were published in 2013; and the years 2017 and 2016 are ranked second and third. Researchers from the US Centers for Disease Control and Prevention have the highest number of papers in this field (210). Alderete J.F. with 111 papers is the most active researcher on trichomoniasis in Scopus. Also, researchers from the US ranked the first with 3,236 papers. In Iran, by the end of 2018, 138 papers on trichomoniasis have been registered in Scopus, which accounts for only one percent of the world's science production in this field.

DISCUSSION AND CONCLUSION

The results following about one century indicated that the number of publications on T. vaginalis is growing and that there is a high level of collaboration among researchers in this field. Moreover, many countries have collaborated internationally on trichomoniasis research with the US as the leading country.

Correlates of trichomoniasis among female sex workers who inject drugs in two Mexico-US border cities

This paper evaluates correlates of trichomoniasis among female sex workers who inject drugs (FSWIDs) in two Mexico-US border cities. HIV-negative FSWIDs aged 18 years or older were enrolled in a study between 2008 and 2010 in Tijuana and Ciudad Juarez (Cd.), Mexico. All participants underwent a baseline interviewer-administered survey and did a rapid test for trichomoniasis. Using regression to estimate prevalence ratios, we examined sociodemographics, sex work characteristics, sexual health and behavior, substance use, and police and violence exposures as potential correlates of trichomoniasis. Of 584 women (284 in Tijuana, 300 in Cd. Juarez), prevalence of trichomoniasis was 33.6%. Factors associated with trichomoniasis in multivariable analysis were having money stolen by police in the past six months (adjusted prevalence ratio [aPR] =1.448, 95% confidence interval [CI] = 1.152-1.821), recent methamphetamine use (aPR = 1.432, CI = 1.055-1.944), lifetime syphilis infection (aPR = 1.360, CI = 1.061-1.743), ever use of a home remedy to treat vaginal symptoms (aPR = 1.301, CI = 1.027-1.649), and number of regular clients in the past month (aPR = 1.006 per client, CI = 1.004-1.009), while controlling for age and city of interview. Alongside the need for trichomoniasis surveillance and treatment programs, findings indicate that both structural and behavioral factors serve as primary correlates of trichomoniasis among FSWIDs in these cities.

Technologies, strategies and approaches for testing populations at risk of sexually transmitted infections: a systematic review protocol to inform prevention and control in EU/EEA countries

OBJECTIVES

This protocol outlines a systematic review methodology, aiming to assess the recent evidence-base for the impact of testing strategies and approaches on access to testing, testing coverage, and linkage to care for populations at risk for specific curable sexually transmitted infections (STIs) (chlamydia, gonorrhoea, syphilis, trichomoniasis, and Mycoplasma genitalium infections).

DATA SOURCES

These include MEDLINE, Embase, PsycINFO, Global Health, Cochrane Database, Epistemonikos, CINAHL Plus, and Web of Science Core Collection.

REVIEW METHODS

Papers reporting primary data from 1 January 2012 onwards will be included. Titles, abstracts, and full texts will be reviewed for inclusion, and data will be extracted using a pre-specified and piloted data extraction form, by two independent reviewers. Experts in the field will be contacted and interviewed for further information about ongoing or unpublished studies. A narrative synthesis of the findings will be conducted.

DISCUSSION

Outcomes of this study will inform policy makers, national and international programme coordinators, public health and clinical experts, and civil society organisations involved in STI prevention and control in EU/EEA countries and elsewhere. The review will provide a direction for future researchers and programmers seeking to improve STI testing services among key populations at high risk for STIs.

SYSTEMATIC REVIEW REGISTRATION

In accordance with guidelines outlined in the PRISMA-P methodology, this protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 30 January 2019: CRD42019118261.

Antiparasitic activity of furanyl N-acylhydrazone derivatives against Trichomonas vaginalis: in vitro and in silico analyses

Background

Trichomonas vaginalis is the causative agent of trichomoniasis, which is one of the most common sexually transmitted diseases worldwide. Trichomoniasis has a high incidence and prevalence and is associated with serious complications such as HIV transmission and acquisition, pelvic inflammatory disease and preterm birth. Although trichomoniasis is treated with oral metronidazole (MTZ), the number of strains resistant to this drug is increasing (2.5–9.6%), leading to treatment failure. Therefore, there is an urgent need to find alternative drugs to combat this disease.

Methods

Herein, we report the in vitro and in silico analysis of 12 furanyl N-acylhydrazone derivatives (PFUR 4, a-k) against Trichomonas vaginalis. Trichomonas vaginalis ATCC 30236 isolate was treated with seven concentrations of these compounds to determine the minimum inhibitory concentration (MIC) and 50% inhibitory concentration (IC₅₀). In addition, compounds that displayed anti-T. vaginalis activity were analyzed using thiobarbituric acid reactive substances (TBARS) assay and molecular docking. Cytotoxicity analysis was also performed in CHO-K1 cells.

Results

The compounds PFUR 4a and 4b, at 6.25 µM, induced complete parasite death after 24 h of exposure with IC₅₀ of 1.69 µM and 1.98 µM, respectively. The results showed that lipid peroxidation is not involved in parasite death. Molecular docking studies predicted strong interactions of PFUR 4a and 4b with T. vaginalis enzymes, purine nucleoside phosphorylase, and lactate dehydrogenase, while only PFUR 4b interacted in silico with thioredoxin reductase and methionine gamma-lyase. PFUR 4a and 4b led to a growth inhibition (< 20%) in CHO-K1 cells that was comparable to the drug of choice, with a promising selectivity index (> 7.4).

Conclusions

Our results showed that PFUR 4a and 4b are promising molecules that can be used for the development of new trichomonacidal agents for T. vaginalis.

School suspension predicts trichomoniasis five years later in a matched sample

BACKGROUND

Young adults who were suspended from school during adolescence are more likely than matched non-suspended youth to be arrested, on probation, or not graduate from high school, which are STI risk factors. This study evaluates whether suspension is a marker for STI risk among young adults who avoid subsequent negative effects.

METHODS

This study evaluated whether suspension predicts a positive test for chlamydia, gonorrhea, or trichomoniasis in a urine sample using matched sampling in the National Longitudinal Study of Adolescent and Adult Health (Add Health), and evaluated potential mediators between suspension and STI status using causal mediation analysis. We used Mahalanobis and exact matched sampling within propensity score calipers to compare 381 youth suspended for the first time in a 1-year period with 980 non-suspended youth. The suspended and non-suspended youth were similar on 67 pre-suspension variables. We evaluated STI outcomes 5 years after suspension.

RESULTS

Before matching, suspended youth were more likely to test positive for trichomoniasis and gonorrhea, but not chlamydia, than non-suspended youth. Suspended youth were more likely to test positive for trichomoniasis 5 years after suspension than matched non-suspended youth (OR = 2.87 (1.40, 5.99)). Below-median household income before suspension explained 9% of the suspension-trichomoniasis association (p = 0.02), but criminal justice involvement and educational attainment were not statistically significantly mediators.

CONCLUSIONS

School suspension is a marker for STI risk. Punishing adolescents for initial deviance may cause them to associate with riskier sexual networks even if they graduate high school and avoid criminal justice system involvement. Suspension may compound disadvantages for youth from below-median-income families, who have fewer resources for recovering from setbacks.

Loop mediated isothermal amplification assay for detection of Trichomonas vaginalis in vaginal swabs among symptomatic women from North India

Trichomonas vaginalis is one of the most common curable sexually transmitted pathogens infecting both men and women worldwide. Unlike traditional methods such as microscopy and culture, nucleic acid amplification tests rapidly detect this agent, assisting in treatment. Conventional polymerase chain reaction (PCR), the loop-mediated isothermal amplification (LAMP), and the Xpert TV assay were evaluated using 28 microscopy positive T. vaginalis samples and 125 microscopy negative samples from symptomatic females of reproductive age. The sensitivity of all tests was 100% and the specificity was 100%, 100%, and 99·2% for PCR, Xpert TV, and LAMP, respectively. The inter-rater reliability was excellent for PCR: Xpert TV (kappa-coefficient = 1) and good for LAMP assay: Xpert TV/PCR (kappa-coefficient = 0·98) and conventional PCR: LAMP (kappa-coefficient = 0·98). The study highlights the importance of PCR for screening T. vaginalis in women, particularly in laboratories where the Xpert-TV assay is not available or not affordable. The LAMP assay showed a lower positive predictive value which merits further evaluation. SIGNIFICANCE AND IMPACT OF THE STUDY: Trichomonas vaginalis is a common sexually transmitted pathogen associated with considerable morbidity and risk of complications. Due to the limitations of traditional diagnostic modalities, three molecular assays were compared: conventional polymerase chain reaction (PCR), Xpert TV assay, and loop mediated isothermal amplification (LAMP) assay for detecting T. vaginalis in symptomatic females. All tests had a sensitivity of 100% and the inter-rater reliability was excellent for PCR: Xpert TV, and good for LAMP assay: Xpert TV/PCR. The translational impact of this study lies in the possible use of conventional PCR and LAMP in laboratories where the Xpert TV assay is not available or not affordable.

Composite thermoresponsive hydrogel with auranofin-loaded nanoparticles for topical treatment of vaginal trichomonad infection

Trichomonas vaginalis is responsible for the most common non-viral sexually-transmitted disease worldwide. Standard treatment is with oral nitro-heterocyclic compounds, metronidazole or tinidazole, but resistance to these drugs is emerging and adverse effects can be problematic. Topical treatment offers potential benefits for increasing local drug concentrations and efficacy, while reducing systemic drug exposure, but no topical strategies are currently approved for trichomoniasis. The anti-rheumatic drug, auranofin (AF), was recently discovered to have significant trichomonacidal activity, but has a long plasma half-life and significant adverse effects. Here, we used this drug as a model to develop a novel topical formulation composed of AF-loaded nanoparticles (NP) embedded in a thermoresponsive hydrogel for intravaginal administration. The AF-NP composite gel showed sustained drug release for at least 12 h, and underwent sol-gel transition with increased viscoelasticity within a minute. Intravaginal administration in mice showed excellent NP retention for >6 h and markedly increased local AF levels, but reduced plasma and liver levels compared to oral treatment with a much higher dose. Furthermore, intravaginal AF-NP gel greatly outperformed oral AF in eliminating vaginal trichomonad infection in mice, while causing no systemic or local toxicity. These results show the potential of the AF-NP hydrogel formulation for effective topical therapy of vaginal infections.

Vaginal dysbiotic bacteria act as pathobionts of the protozoal pathogen Trichomonas vaginalis

Trichomoniasis, a prevalent sexually transmitted infection caused by the protozoan parasite Trichomonas vaginalis, is often accompanied by a vaginal dysbiotic microbiota of pathogenic potential. Our objective was to investigate whether these dysbiotic bacteria act as pathobionts of T. vaginalis infection by altering pathogenic capabilities of the parasite, particularly in regard to adhesion to vaginal substrates and viability of human ectocervical cells. Assays interrogated the performance of T. vaginalis adhesion to biofilm produced by vaginal dysbiotic bacteria and whether these bacteria were capable of altering the ability of the parasite to bind to mucins and cells. The binding activities of T. vaginalis were quantified by flow cytometry. Host cell viability and apoptosis, as affected by T. vaginalis with or without the bacteria, were also measured experimentally. An in vitro biofilm was shown to provide adhesion for T. vaginalis. The binding of parasites to mucins and cells was modulated by the vaginal dysbiotic bacteria. Parasite cytoadhesion was significantly increased by these bacteria. In addition, these bacteria enhanced the pathogenic effects of the parasite to host cells. Together, this study showed that dysbiotic bacteria accompanying T. vaginalis infection in the vagina function as pathobionts as they are capable of enhancing the pathogenic capabilities of this parasite. This study highlights the importance of understanding the contribution of the vaginal microbiome to trichomoniasis.

Management of Resistant Trichomoniasis

PURPOSE OF REVIEW

Trichomonas vaginalis is the most prevalent sexually transmitted parasite in the USA; resistant infection is emerging. New drug therapies and dosing regimens of standard therapies are being studied to treat resistant infection.

RECENT FINDINGS

Diagnosis of trichomoniasis has become more sensitive, specific, and widely available with the advent of nucleic acid amplification tests (NAATs). Women with resistant trichomoniasis should be treated with high-dose regimens of metronidazole or tinidazole. Alternative treatment options have been described, and there has been some success particularly with high-dose tinidazole/intravaginal paromomycin cream combination, intravaginal boric acid, and intravaginal metronidazole/miconazole. Resistant trichomoniasis is a growing public health concern with implications for long-term health consequences. More data are needed to further evaluate mechanisms by which resistance occurs as well as promising therapies for those affected.

Trichomonas vaginalis and Mycoplasma infections among women with vaginal discharge at Fann teaching hospital in Senegal

Background:

Trichomonas vaginalis and genital Mycoplasmas are two synergistic pathogens, but in many settings, limited data on the co-infection by Trichomonas and Mycoplasma are available.

Objective:

This study aimed at assessing Mycoplasma prevalence and its association with Trichomonas vaginalis among women with vaginal discharge.

Materials and Methods:

A retrospective analysis of laboratory records (2012 and 2013) from patients referred at the Fann teaching hospital in Dakar Senegal for vaginal discharge was carried out. Detection of genital mycoplasmas was based on the commercial Kit Mycoplasma Duo Bio-Rad™ using endo-cervical swabs. Vaginal swabs were collected and examined using optic microscopy with 40x magnification to detect T. vaginalis.

Results:

Overall, data from 1257 women were analysed. Prevalence of Mycoplasma hominis represented 57.4%, 95%CI(54.6-60.1), versus 54.9%, 95%CI(52.1-57.5) for Ureaplasma urealyticum. Trichomonas vaginalis infection was observed with a frequency of 3%. Out of the 50 patients with trichomoniasis, 76% of them were co-infected by Mycoplasma hominis and patients with Trichomonas vaginalis had an increased risk of acquiring Mycoplasma infection (adjusted OR:2.5, 95%CI(1.2-5.2);p=0.02)).

Conclusion:

Trichomonas vaginalis and Mycoplasmas are two closely associated pathogens in the urogenital tract of women. This clinically significant symbiotic action may require systematic screening of Mycoplasma among patients with trichomoniasis for optimal management of sexually transmitted infections.

Epinecidin-1: A marine fish antimicrobial peptide with therapeutic potential against Trichomonas vaginalis infection in mice

Trichomoniasis is caused by infection with the protozoan parasite Trichomonas vaginalis, and prolonged persistence may lead to serious ill effects in patients. Thus, the development of new therapeutic strategies to combat drug-resistant T. vaginalis would be clinically beneficial. Antimicrobial peptides (AMPs) comprise an emerging class of molecules that may serve as effective alternatives to antibiotics. In this report, we demonstrate that the synthetic fish AMP, Epinecidin-1 (Epi-1), acts against T. vaginalis both in vitro and in vivo. Under in vitro conditions, Epi-1 disrupted the membrane of metronidazole-resistant T. vaginalis and completely killed the pathogen. To mimic human infection in vivo, estradiol-stimulated mice with vaginal Lactobacillus acidophilus colonization were infected with T. vaginalis, followed by treatment with Epi-1, Vigill, metronidazole or furazolidone. After seven days, the T. vaginalis content was effectively decreased in Epi-1 treated mice, as measured by acridine orange staining of wet smears and tissue biopsies, as well as qPCR of vaginal discharge DNA. Taken together, our results demonstrate that Epi-1 is a strong candidate for development as an alternative therapeutic for T. vaginalis infection.

Trichomonas vaginalis infection and the diagnostic significance of detection tests among Ghanaian outpatients

Background

There is little data on Trichomonas vaginalis infection in Ghana. This study evaluated the prevalence of trichomoniasis using different diagnostic methods and determined the risk factors for infection in patients.

Methods

A structured questionnaire was administered. Vaginal swabs, urethral swabs and urine specimens were obtained from consenting patients; and the samples processed following standard protocols. The presence of T. vaginalis was determined using wet mount microscopy and polymerase chain reaction (PCR) as gold standard. We also assessed the diagnostic performance the JD’s Trichomonas V® rapid antigen test to inform clinical practice.

Results

The PCR assay detected T. vaginalis positivity in 64 of 150 patients (42.6, 95%CI:35.0, 50.6) including all positive samples of wet mount microscopy and JD’s Trichomonas V® test. Wet mount microscopy showed low sensitivity (31.6%), high specificity (100%), moderate positive predictive value (75.0%), moderate positive likelihood ratio (3.0), and weak agreement (Cohen’s kappa, 0.283) with PCR assay. The JD’s Trichomonas V® test displayed lower sensitivity (25.0%), specificity (83.3%), and weaker measure of agreement (Cohen’s kappa, 0.233) with PCR. In multivariate analysis, the strongest independent predictor for T. vaginalis was female gender [adjusted odds ratio (AOR), 24.89; 95% confidence interval (CI): 10.58, 51.21; P-value< 0.001]. Knowledge of STI showed a protective effect against infection with the parasite (AOR, 0.13; 95%CI: 0.07, 0.29; P-value< 0.017).

Conclusion

The sensitivity of wet mount microscopy was low for T. vaginalis screening in our region. The JD’s Trichomonas V® test should not be considered as an alternative test. We recommend mandatory PCR assay for confirmation of negative wet mount results.

Anti-Trichomonas vaginalis activity of chalcone and amino-analogues

Trichomoniasis is the most common non-viral sexually transmitted disease worldwide and can lead to serious consequences in reproductive health, cancer, and HIV acquisition. The current approved treatment present adverse effects and drug resistance data on this neglected parasitic infection is underestimated. Chalcones are a family of molecules that present biological applications, such as activity against many pathogenic organisms including protozoan pathogens. Chalcone (1) and three amino-analogues (2-4) were synthesized by Claisen-Schmidt condensation reaction and had their activity evaluated against the parasitic protozoan Trichomonas vaginalis. This bioassay indicated the presence and position of the amino group on ring A was crucial for anti-T. vaginalis activity. Among these, 3'-aminochalcone (3) presented the most potent effect and showed high cytotoxicity against human vaginal cells. On the other hand, 3 was not able to exhibit toxicity against Galleria mellonella larvae, as well as the hemolytic effect on human erythrocytes. Trophozoites of T. vaginalis were treated with 3, and did not present significant reactive oxygen species (ROS) accumulation, but induced a significantly higher ROS accumulation in human neutrophils after co-incubation. T. vaginalis pyruvate:ferredoxin oxidoreductase (PFOR) and β-tubulin gene expression was not affected by 3.

Chemotherapeutic options for the treatment of human trichomoniasis

Trichomonas vaginalis is the causative agent of the most common non-viral sexually transmitted disease worldwide. The infection may be associated with severe complications, including infertility, preterm labour, cancer and an increased risk of human immunodeficiency virus (HIV) transmission. Treatment remains almost exclusively based on 5-nitroimidazoles, but resistance is on the rise. This article provides an overview of clinically evaluated systemic and topical treatment options for human trichomoniasis and summarises the current state of knowledge on various herbal, semisynthetic and synthetic compounds evaluated for their anti-Trichomonas efficacy in vitro.

Substituted carbamothioic amine-1-carbothioic thioanhydrides as novel trichomonicidal fungicides: Design, synthesis, and biology

Sexually transmitted diseases like trichomoniasis along with opportunistic fungal infections like candidiasis are major global health burden in female reproductive health. In this context a novel non-nitroimidazole class of substituted carbamothioic amine-1-carbothioic thioanhydride series was designed, synthesized, evaluated for trichomonacidal and fungicidal activities, and was found to be more active than the standard drug Metronidazole (MTZ). Compounds were trichomonicidal in the MIC ranges of 4.77-294.1 μM and 32.46-735.20 μM against MTZ-susceptible and -resistant strains, respectively. Further, compounds inhibited the growth of at least two out of ten fungal strains tested at MIC of 7.50-240.38 μM. The most active compound (20) of this series was 3.8 and 9.5 fold more active than the MTZ against the two Trichomonas strains tested. Compound 20 also significantly inhibited the sulfhydryl groups present over Trichomonas vaginalis and was found to be more active than the MTZ in vivo. Further, a docking analysis carried out with cysteine proteases supported their thiol inhibiting ability and preliminary pharmacokinetic study has shown good distribution and systemic clearance.

Vaginitis: Beyond the Basics

Vaginal complaints are one of the most common reasons women seek the advice of a health care provider. Uncomplicated infections such as vulvovaginal candidiasis, bacterial vaginosis, or trichomoniasis are easy to diagnose and treat. However, about 8% of patients will have a more complicated course with failure to respond to treatment or rapid recurrence of symptoms. Understanding the need for a methodical, diagnostic approach to help these women with recurrent or refractory cases of vaginal symptoms will aid the clinician achieve successful patient outcomes.

Recent developments in anti-Trichomonas research: An update review

Trichomonas vaginalis is a major non-viral sexually-transmitted infection resulted into serious obstetrical and gynecological troubles. The increasing resistance to nitroimidazole therapy and recurrence makes it crucial to develop new drugs against trichomoniasis. Over the past few years, a large number of research articles highlighting the synthetic and natural product research to combat Trichomonas vaginalis have been published. Electronic databases were searched to collect all data from the year 2006 through June 2017 for anti-Trichomonas activity potential of synthetic and natural products. This review article put together the synthetic and natural product research to find out an effective metronidazole alternative to cure trichomoniasis.