The Epidemiological Impact of STIs among General and Vulnerable Populations of the Amazon Region of Brazil: 30 years of Surveillance.

Sexually transmitted infections (STIs) represent a worldwide public health problem and, although many of them are curable, they continue to be neglected, especially in areas with a low human development index, such as in the northern region of Brazil. This review describes the results of 30 years of studies at the Virus Laboratory at the Federal University of Pará, including the prevalence and molecular epidemiology of HIV-1, HTLV-1/2, HPV, HBV, Treponema pallidum and Chlamydia trachomatis among urban and non-urban populations, and also in vulnerable groups in the Brazilian Amazon. Control strategies and challenges in preventing STIs are discussed considering this immense geographic region, where essential health services are unable to reach the entire population, especially the most vulnerable, such as female sex workers, people who use illicit drugs, remnants of quilombolos and indigenous communities.

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.

Assessment of syndromic management of curable sexually transmitted and reproductive tract infections among pregnant women: an observational cross-sectional study.

BACKGROUND: This study estimated the prevalence of curable sexually transmitted and reproductive tract infections (STIs/RTIs) among pregnant women attending antenatal care (ANC) in rural Zambia, evaluated the effectiveness of syndromic management of STIs/RTIs versus reference-standard laboratory diagnoses, and identified determinants of curable STIs/RTIs during pregnancy. METHODS: A total of 1086 pregnant women were enrolled at ANC booking, socio-demographic information and biological samples were collected, and the provision of syndromic management based care was documented. The Piot-Fransen model was used to evaluate the effectiveness of syndromic management versus etiological testing, and univariate and multivariate logistic regression analyses were used to identify determinants of STIs/RTIs. RESULTS: Participants had a mean age of 25.6 years and a mean gestational age of 22.0 weeks. Of 1084 women, 700 had at least one STI/RTI (64.6%; 95% confidence interval [CI], 61.7, 67.4). Only 10.2% of infected women received any treatment for a curable STI/RTI (excluding syphilis). Treatment was given to 0 of 56 women with chlamydia (prevalence 5.2%; 95% CI, 4.0, 6.6), 14.7% of participants with gonorrhoea (prevalence 3.1%; 95% CI, 2.2, 4.4), 7.8% of trichomoniasis positives (prevalence 24.8%; 95% CI, 22.3, 27.5) and 7.5% of women with bacterial vaginosis (prevalence 48.7%; 95% CI, 45.2, 51.2). An estimated 7.1% (95% CI, 5.6, 8.7) of participants had syphilis and received treatment. Women < 20 years old were more likely (adjusted odds ratio [aOR] = 5.01; 95% CI: 1.23, 19.44) to have gonorrhoea compared to women ≥30. The odds of trichomoniasis infection were highest among primigravidae (aOR = 2.40; 95% CI: 1.69, 3.40), decreasing with each subsequent pregnancy. Women 20 to 29 years old were more likely to be diagnosed with bacterial vaginosis compared to women ≥30 (aOR = 1.58; 95% CI: 1.19, 2.10). Women aged 20 to 29 and ≥ 30 years had higher odds of infection with syphilis, aOR = 3.96; 95% CI: 1.40, 11.20 and aOR = 3.29; 95% CI: 1.11, 9.74 respectively, compared to women under 20. CONCLUSIONS: Curable STIs/RTIs were common and the majority of cases were undetected and untreated. Alternative approaches are urgently needed in the ANC setting in rural Zambia.

Prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis including relevant resistance-associated mutations in a single center in the Netherlands.

PURPOSE: In this study, we report the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG) and Trichomonas vaginalis (TV) amongst clinical specimens of patients suspected for sexually transmitted infections received at our laboratory and in addition report the prevalence of resistance-associated mutations (RAM) for ciprofloxacin in NG and azithromycin and moxifloxacin in MG. METHODS: All specimens received from December 2018 to May 2019 were tested for the four pathogens. In addition, the presence of RAM associated with resistance to ciprofloxacin in NG and to azithromycin and moxifloxacin in MG was determined by different real-time PCR assays on all NG- and MG-positive specimens. RESULTS: CT was detected most often (267/2613, 10.2%), followed by MG (106/2592, 4.1%), NG (41/2613, 1.6%) and TV (10/2592, 0.4%) amongst all specimens. The prevalence of ciprofloxacin RAM in NG was 21.2%, and the prevalence of RAM in MG was 40.6% for azithromycin and 8.1% for moxifloxacin. Nearly all specimens containing moxifloxacin-resistant MG also contained azithromycin-resistant MG. CONCLUSION: CT is found most often in our population followed by MG and NG. By using molecular assays to detect RAM supplementary to pathogen identification of NG and MG, optimal therapy can be advised.

Factors associated with sexually transmitted infection diagnosis in women who have sex with women, women who have sex with men and women who have sex with both.

INTRODUCTION: Many US women report same sex behaviour, yet data on risk factors and STIs in women who have sex with women (WSW), women who have sex with both men and women (WSB) and how these compare to women who have sex with men only (WSM) remain limited. Here we compared self-identified WSW, WSB and WSM attending two STI clinics in Baltimore, Maryland. METHODS: This was a retrospective analysis using a database of first clinic visits 2005-2016. WSW and WSB were compared with an age-matched random sample of WSM. Proportions were compared using the χ2 test. Acute STI (aSTI) was defined as gonorrhoea (Neisseria gonorrhoeae, GC), chlamydia (Chlamydia trachomatis, CT), trichomonas (Trichomonas vaginalis, TV) or early syphilis. Logistic regression was used to assess aSTI predictors. CT testing was not uniformly done, so a sensitivity analysis removing CT from the aSTI definition was conducted. RESULTS: Visits from 1095 WSW, 1678 WSB and 2773 WSM were analysed. WSB had equal or higher test positivity for all STIs except urogenital chlamydia, had more sexual partners, were more likely to engage in transactional sex and were more likely to report drug use and binge drinking than WSM (p≤0.01). WSW had lower test positivity for urogenital GC and CT than WSM or WSB, but comparable test positivity for TV, higher reported binge drinking and comparable reported substance use as WSM. Younger age and cocaine use predicted STI diagnosis only in WSM. CONCLUSIONS: WSB in these clinics bear an equal or higher burden of most STIs, have more partners and report more substance use than WSM. WSW carry a lower, but still substantial burden of STIs, and many report substance use. Factors predicting STI diagnosis differ between WSW, WSB and WSM suggesting that tailored STI prevention and testing approaches are needed in these groups.

Sexual Transmission of Visceral Leishmaniasis: A Neglected Story.

For visceral leishmaniasis (VL), a major vector-borne parasitic disease, an alternative sexual transmission route is well documented in dogs but evidence is lacking in humans. Here, we discuss the current knowledge and key questions to be answered as it may be an additional obstacle in ongoing VL elimination programs.

Evaluation of the effect of some medicinal plants on cultured Trichomonas Vaginalis.

INTRODUCTION: Trichomoniasis is a worldwide sexually transmitted disease caused by Trichomonas vaginalis. It inflicts severe complications to the human genitourinary system. The devastating negative effects and the emergence of resistance to common medication impose the search for safer and effective alternatives. This research aimed to investigate the effect of the Allium sativum, Nigella sativa crude extracts (NsCE) and the combination between their most effective doses with metronidazole. METHODOLOGY: Vaginal swabs were obtained from symptomatic patients, and cultured on Diamond's medium. Assessment of various concentrations of these herbs at different follow-up periods was done by counting the number of dead T. vaginalis trophozoites using the hemocytometer and trypan blue staining. Transmission electron microscope study was done. RESULTS: NsCE 9 mg/mL yielded the highest lethal effect on T. vaginalis trophozoites after 72 hours, compared with metronidazole. Combination of NsCE 9 mg/mL and metronidazole 50 µg/mL gave the best result. Additionally, Tomex90 µg/mL, represents a tolerable effect after 72 hours, but metronidazole 100 µg/mL still has higher effect. These results were confirmed by the ultrastructural changes observed in T. vaginalis trophozoites, signifying severe damage of nucleus and cytoplasm with large vacuolization and cell membrane defects. CONCLUSIONS: NsCE is a promising anti-Trichomonas especially its combination with metronidazole which showed a high synergistic effect.

Optimising treatments for sexually transmitted infections: surveillance, pharmacokinetics and pharmacodynamics, therapeutic strategies, and molecular resistance prediction.

Progressive antimicrobial resistance in Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis has created a pressing need for treatment optimisations for sexually transmitted infections (STIs). In this Review, we aim to highlight urgent needs in global STI management, including: (1) improved surveillance to monitor antimicrobial resistance and clinical outcomes; (2) systematic pharmacokinetic and pharmacodynamic evaluations to ensure resistance suppression and bacterial eradication at all sites of infection; (3) development of novel, affordable antimicrobials; and (4) advancements in new molecular and point-of-care tests to detect antimicrobial resistance determinants. Antimicrobial resistance among STIs is a global public health crisis. Continuous efforts to develop novel antimicrobials will be essential, in addition to other public health interventions to reduce the global STI burden. Apart from prevention through safer sexual practices, the development of STI vaccines to prevent transmission is a crucial research priority.

Molecular epidemiology and socio-demographic risk factors of sexually transmitted infections among women in Lebanon.

BACKGROUND: Sexually transmitted infections (STIs) cause a major public health problem that affect both men and women in developing and developed countries. The aim of the study was to estimate the prevalence of 11 STIs among women who voluntarily participated in the study, while seeking gynecological checkup. The existence of an association between the presence of pathogens and symptoms and various sociodemographic risk factors was assessed. METHODS: A total of 505 vaginal and cervical specimens were collected from women above 18 years of age, with or without symptoms related to gynecological infections. Nucleic acid was extracted and samples were tested by real-time PCR for the following pathogens: Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Ureaplasma urealyticum, Urealplasma parvum, Trichomonas vaginalis, Mycoplasma hominis, Mycoplasma girerdii, Gardnerella vaginalis, Candida albicans and Human Papillomavirus (HPV). Positive HPV samples underwent genotyping using a microarray system. RESULTS: Of the 505 samples, 312 (62%) were screened positive for at least one pathogen. Of these, 36% were positive for Gardnerella vaginalis, 35% for Ureaplasma parvum, 8% for Candida albicans, 6.7% for HPV, 4.6% for Ureaplasma urealyticum, 3.6% for Mycoplasma hominis, 2% for Trichomonas vaginalis, 0.8% for Chlamydia trachomatis, 0.4% for Mycoplasma girerdii, 0.2% for Mycoplasma genitalium and 0.2% for Neisseria gonorrhoeae. Lack of symptoms was reported in 187 women (37%), among whom 61% were infected. Thirty-four samples were HPV positive, with 17 high risk HPV genotypes (HR-HPV); the highest rates being recorded for types 16 (38%), 18 (21%) and 51 (18%). Out of the 34 HPV positives, 29 participants had HR-HPV. Association with various risk factors were reported. CONCLUSIONS: This is the first study that presents data about the presence of STIs among women in Lebanon and the MENA region by simultaneous detection of 11 pathogens. In the absence of systematic STI surveillance in Lebanon, concurrent screening for HPV and PAP smear is warranted.

Bacterial vaginosis-associated vaginal microbiota is an age-independent risk factor for Chlamydia trachomatis, Mycoplasma genitalium and Trichomonas vaginalis infections in low-risk women, St. Petersburg, Russia.

The large majority of studies investigating associations between bacterial vaginosis (BV) and sexually transmitted infections (STIs) have been conducted among predominantly young women with high risk for STIs. Since a risky sexual behavior is a significant risk factor for both STIs and BV, this creates a bias toward an increased association between BV and STIs. This study evaluated associations between BV-associated vaginal microbiota and STIs (Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, and Neisseria gonorrhoeae) in a population of women with low risk for STIs and investigated STI outcomes depending on the dominating Lactobacillus species. Repository cervicovaginal samples collected from reproductive-age women from January 2014 to February 2019 were characterized for vaginal microbiota types and the STIs using multiplex real-time PCR assays. In total, 95 STI-positive and 91 STI-negative samples were included. A significant, age-independent association between BV-associated vaginal microbiota and the presence of C. trachomatis, M. genitalium, and T. vaginalis infections was identified (age-adjusted odds ratios 2.92 [95% confidence interval (CI) 1.24-7.03], 2.88 [95% CI 1.19-7.16], and 9.75 × 107 [95% CI 13.03-∞], respectively). Normal vaginal microbiota dominated by Lactobacillus crispatus, L. gasseri, or L. jensenii was a strong protective factor against C. trachomatis and/or M. genitalium infections, whereas L. iners-dominated microbiota was not significantly associated with C. trachomatis and/or M. genitalium positivity. The results of the present study confirm that STI prevention strategies should include interventions that also reduce the incidence of BV and promote a protective vaginal microbiota in both high- and low-risk women.

Retrospective Chart Analysis of Child and Adolescent Trichomonas vaginalis Infection in Houston, Texas.

BACKGROUND: Trichomonas vaginalis infection causes significant morbidity in the United States. Despite its high national disease burden, the epidemiologic characteristics of child and adolescent cases are not well understood. In this study, we aimed to describe the socioeconomic, transmission risk factors, clinical manifestations, and geospatial variables associated with cases of T vaginalis infection in the Houston, Texas, metropolitan area. METHODS: We performed a retrospective chart abstraction of all T vaginalis cases at 2 large pediatric hospitals in Houston between 2008 and 2016. RESULTS: We identified 87 patients (mean age, 16 years; range, 4-18 years); 30% of them were asymptomatic, and 39% were coinfected with another sexually transmitted infection(s). Almost all T vaginalis infections in sexually assaulted patients were diagnosed incidentally. Geospatial analysis identified clustering of cases in areas of high poverty and in minority populations. CONCLUSIONS: Our findings indicate that children and adolescents are at risk for T vaginalis infection; however, their risk factors might differ from those in adults. In addition, our geospatial analysis revealed the need for dedicated resources in neighborhoods associated with health disparities to prevent future incident cases.

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.

Major factors associated to persistence of bovine trichomoniasis in a mandatory control plan: A eight year retrospective study in La Pampa, Argentine.

Bovine trichomoniasis is a venereal disease caused by the flagellate protozoan Tritrichomonas foetus. Infection is related to low conception rates and would have significant impact on calf crop. The state of La Pampa started in 2006 an unprecedented mandatory control program for eradication of bovine trichomoniasis. The compulsory participation of all cattle producers and the yearly control of every bull should be followed by culling of every positive animal. This retrospective study on data from eight years of the control plan showed that 80% of farms had a single year of positive tests. In these farms, positive tests showed a strong decay of disease during the first years that reached a baseline by 2012. A non negligeable proportion of positive bulls in this group can be attributed to false positive tests. Oppositely, farms with two or more years of positive diagnosis accounted for a great proportion of recent cases. These farms were more likely related to less intensive control measures. The non exclusion of carrier bulls is the major factor contributing to the persistance of bovine trichomoniasis.

Sexual Transmission of Intestinal Parasites and Other Enteric Pathogens among Men Who Have Sex with Men Presenting Gastrointestinal Symptoms in an STI Unit in Barcelona, Spain: A Cross-Sectional Study.

Sexually transmitted infections (STIs) are a major problem worldwide. In addition, the spectrum of STIs is now expanding, including parasitic, bacterial, and viral infections. The study retrospectively describes the presence of enteric pathogens among 73 patients with gastrointestinal symptoms of enteritis and proctocolitis attending to an STI unit in Barcelona, Spain, between 2015 and 2016. Only patients investigated for intestinal parasitic infections were included in the study. Different diagnostic procedures were established for the detection of parasites, bacterial enteropathogens, and other STI agents. Entamoeba histolytica was the most prevalent pathogen in our cohort (20.5%), especially among individuals with proctocolitis. Contrarily, Giardia intestinalis was detected in 11.0% of patients, only associated with enteritis cases. Polymicrobial infections were common in our study (45.2%). Of note, 55.6% of shigellosis cases were coinfected with E. histolytica. The investigation highlights the importance of including parasites as differential gastrointestinal diagnosis, disregarding travel history, particularly among risk populations.

20S Proteasome as a Drug Target in Trichomonas vaginalis.

Trichomoniasis is a sexually transmitted disease with hundreds of millions of annual cases worldwide. Approved treatment options are limited to two related nitro-heterocyclic compounds, yet resistance to these drugs is an increasing concern. New antimicrobials against the causative agent, Trichomonas vaginalis, are urgently needed. We show here that clinically approved anticancer drugs that inhibit the proteasome, a large protease complex with a critical role in degrading intracellular proteins in eukaryotes, have submicromolar activity against the parasite in vitro and on-target activity against the enriched T. vaginalis proteasome in cell-free assays. Proteomic analysis confirmed that the parasite has all seven α and seven ß subunits of the eukaryotic proteasome although they have only modest sequence identities, ranging from 28 to 52%, relative to the respective human proteasome subunits. A screen of proteasome inhibitors derived from a marine natural product, carmaphycin, revealed one derivative, carmaphycin-17, with greater activity against T. vaginalis than the reference drug metronidazole, the ability to overcome metronidazole resistance, and reduced human cytotoxicity compared to that of the anticancer proteasome inhibitors. The increased selectivity of carmaphycin-17 for T. vaginalis was related to its >5-fold greater potency against the ß1 and ß5 catalytic subunits of the T. vaginalis proteasome than against the human proteasome subunits. In a murine model of vaginal trichomonad infection, proteasome inhibitors eliminated or significantly reduced parasite burden upon topical treatment without any apparent adverse effects. Together, these findings validate the proteasome of T. vaginalis as a therapeutic target for development of a novel class of trichomonacidal agents.

Sexual Transmission of American Trypanosomes from Males and Females to Naive Mates.

American trypanosomiasis is transmitted to humans by triatomine bugs through the ingestion of contaminated food, by blood transfusions or accidently in hospitals and research laboratories. In addition, the Trypanosoma cruzi infection is transmitted congenitally from a chagasic mother to her offspring, but the male partner's contribution to in utero contamination is unknown. The findings of nests and clumps of amastigotes and of trypomastigotes in the theca cells of the ovary, in the goniablasts and in the lumen of seminiferous tubules suggest that T. cruzi infections are sexually transmitted. The research protocol herein presents the results of a family study population showing parasite nuclear DNA in the diploid blood mononuclear cells and in the haploid gametes of human subjects. Thus, three independent biological samples collected one year apart confirmed that T. cruzi infections were sexually transmitted to progeny. Interestingly, the specific T. cruzi antibody was absent in the majority of family progeny that bore immune tolerance to the parasite antigen. Immune tolerance was demonstrated in chicken refractory to T. cruzi after the first week of embryonic growth, and chicks hatched from the flagellate-inoculated eggs were unable to produce the specific antibody. Moreover, the instillation of the human semen ejaculates intraperitoneally or into the vagina of naive mice yielded T. cruzi amastigotes in the epididymis, seminiferous tubule, vas deferens and uterine tube with an absence of inflammatory reactions in the immune privileged organs of reproduction. The breeding of T. cruzi-infected male and female mice with naive mates resulted in acquisition of the infections, which were later transmitted to the progeny. Therefore, a robust education, information and communication program that involves the population and social organizations is deemed necessary to prevent Chagas disease.

Trichomonas vaginalis and Mycoplasma hominis: new tales of two old friends.

Trichomonas vaginalis is an anaerobic protist, responsible for the most prevalent non-viral sexually transmitted infection in humans. One of the most intriguing aspects of T. vaginalis pathobiology is the complex relationship with intracellular microbial symbionts: a group of dsRNA viruses belonging to family of Totiviridae (T. vaginalis virus), and eubacteria belonging to the Mycoplasma genus, in particular Mycoplasma hominis. Both microorganisms seem to strongly influence the lifestyle of T. vaginalis, suggesting a role of the symbiosis in the high variability of clinical presentation and sequelae during trichomoniasis. In the last few years many aspects of this unique symbiotic relationship have been investigated: M. hominis resides and replicates in the protozoan cell, and T. vaginalis is able to pass the bacterial infection to both mycoplasma-free protozoan isolates and human epithelial cells; M. hominis synergistically upregulates the proinflammatory response of human monocytes to T. vaginalis. Furthermore, the influence of M. hominis over T. vaginalis metabolism and physiology has been characterized. The identification of a novel species belonging to the class of Mollicutes (Candidatus Mycoplasma girerdii) exclusively associated to T. vaginalis opens new perspectives in the research of the complex series of events taking place in the multifaceted world of the vaginal microbiota, both under normal and pathological conditions.