The Neglected Role of Trichomonas tenax in Oral Diseases: A Systematic Review and Meta-analysis

Clinical implications of trichomonads detected in bronchoalveolar fluid by metagenomic next-generation sequencing: a multicenter retrospective study

Background

Pulmonary trichomoniasis is considered a neglected disease due to failures in recognizing it, stemming from insensitive microbial methods and a lack of specific clinical features. This study aims to analyze the clinical implications of trichomonads detected in bronchoalveolar lavage fluid (BALF) by metagenomic next-generation sequencing (mNGS).

Methods

This multicenter retrospective study included patients diagnosed with pneumonia, admitted to three tertiary hospitals in China from July 2018 to September 2022, with trichomonads detected in BALF through mNGS. The analysis covered demographics, comorbidities, symptoms, laboratory findings, mNGS results, clinical treatment, and outcomes of these patients.

Results

A total of 17 patients were enrolled, comprising 14 males and 3 females. Trichomonas tenax and Trichomonas vaginalis were detected by mNGS in BALF samples of 15 and 2 patients, respectively. Patients were categorized into two groups based on the presence of risk factors for trichomonad infection, including immunocompromised conditions, uncontrolled diabetes mellitus, oral/periodontal diseases, and aspiration. Among 11 patients with risk factors (Case 1-11), 4 received nitromidazoles as part of comprehensive treatment, achieving a 100% treatment success rate. The remaining 7 patients, who did not receive nitromidazoles, had only one achieving relief after broad-spectrum antimicrobial therapy, resulting in a 14.3% treatment success rate. For the 6 patients without any risk factors for trichomonad infection (Case 12-17), none received nitromidazoles during hospitalization. However, 4 out of these 6 patients (66.7%) eventually recovered.

Conclusion

mNGS proves to be an efficient tool for detecting trichomonads in BALF samples. Comprehensive analysis of clinical features and laboratory indicators is essential to distinguish between infection and colonization of trichomonads. Pulmonary trichomoniasis should not be overlooked when trichomonads are detected in BALF from patients with risk factors.

Expansion Microscopy of trichomonads

Light microscopy has significantly advanced in recent decades, especially concerning the increased resolution obtained in fluorescence images. Here we present the Expansion Microscopy (ExM) technique in two parasites, Trichomonas vaginalis and Tritrichomonas foetus, which significantly improved the localization of distinct proteins closely associated with cytoskeleton by immunofluorescence microscopy. The ExM techniques have been used in various cell types, tissues and other protist parasites. It requires the embedment of the samples in a swellable gel that is highly hydrophilic. As a result, cells are expanded 4.5 times in an isotropic manner, offering a spatial resolution of ∼70 nm. We used this new methodology not only to observe the structural organization of protozoa in more detail but also to increase the resolution by immunofluorescence microscopy of two major proteins such as tubulin, found in structures formed by microtubules, and costain 1, the only protein identified until now in the T. foetus's costa, a unique rod-shaped like structure. The individualized microtubules of the axostyle were seen for the first time in fluorescence microscopy and several other details are presented after this technique.

Entamoeba gingivalis and Trichomonas tenax: Protozoa parasites living in the mouth

OBJECTIVE

This review article aims to summarize the existing data on the history, biology and potential pathogenicity of Entamoeba gingivalis and Trichomonas tenax in periodontal disease, as well as the available techniques for laboratory diagnosis.

DESIGN

A detailed review of scientific literature available up to October 1, 2022 in three databases (PubMed, Scopus and Web of Science) was performed relevant to biology, biochemistry, epidemiology, and experimental studies on infection by E. gingivalis and T. tenax, as well as laboratory techniques for the diagnosis of both protozoa in periodontal diseases.

RESULTS

Accumulated evidence over the decades indicates that the protozoa E. gingivalis and T. tenax are able to interact with host cells and induce inflammation in the periodontal tissue by promoting the expression of pro-inflammatory molecules and the recruitment of neutrophils, contributing to the periodontal disease process. Among the available techniques for the laboratory diagnosis, culture and molecular assays seems to be the best tools for detection of both protozoan parasites.

CONCLUSIONS

E. gingivalis and T. tenax are potentially pathogens that colonize the oral cavity of humans and may cause periodontal disease.

Molecular epidemiology and associated risk factors of oral cavity parasites in hemodialysis patients in western Iran

Renal disorders are able to make patients more susceptible to infections, including those caused oral cavity infections. Today, it has been proven that during end stage renal failure, hemodialysis results in acquired immune response defects through failings of humoral and cell-mediated immune. This survey was intended to assess the molecular epidemiology and associated risk factors of Entamoeba gingivalis and Trichomonas tenax as the main oral cavity protozoa in hemodialysis patients in Lorestan Province, western Iran. The investigation was performed on 73 hemodialysis patients referring to hemodialysis centers of Lorestan Province, Iran during May 2021 to February 2022. The frequency of oral cavity protozoa was investigated using microscopic and conventional polymerase chain reaction (PCR). A provided questionnaire with a number of demographical information and related risk factors was completed for each patient. The results showed that E. gingivalis and T. tenax parasites were found in 18 (24.6%) and 20 (27.4%) of the hemodialysis participants by microscopic and PCR test, respectively. Among samples, 13 (17.8%) of the hemodialysis participants were infected with E. gingivalis; whereas 7 (9.6%) of the participants were positive for T. tenax. No significant association was reported between gender, age, education, flossing, use of mouthwash, and prevalence of oral protozoa in hemodialysis participants. However, a significant correlation was observed among between living in rural regions (OR = 13.16; 95% CI = 2.64-56.81; p = 0.002), brushing teeth (OR = 8.51; 95% CI = 1.71-42.3; p = 0.009) and prevalence of oral protozoa in hemodialysis participants. The findings of these epidemiological study clearly showed the high frequency of oral cavity parasites in hemodialysis patients in Lorestan Province, Western Iran. Awareness of the main risk factors for oral cavity parasites particularly teeth brushing is necessary in refining public and oral health policies in hemodialysis patients. Consequently, dental practitioners, nephrologist, and urologist must be alert of these risk factors to carefully identify and achieve oral health concerns in hemodialysis patients to prevent the oral diseases and infections.

Trichomonas tenax: A Neglected Protozoan Infection in the Oral Cavities of Humans and Dogs-A Scoping Review

Trichomonas tenax is a flagellated protozoan parasite found in the oral cavities of humans and animals and has been associated with periodontal disease, the most prevalent inflammatory disease affecting them all. Studies have shown that T. tenax can cause damage to mammalian cells and secretes virulent proteins, such as cysteine. It is presently considered zoonotic. Despite the few studies that have been done, the pathogenicity of this oral protozoan is still not fully understood. A database search was performed in July 2022 using PubMed and Google Scholar to retrieve data eligible for this study. PRISMA-ScR guidelines were followed to conduct this scoping review. A total of 321 articles were found with 87 included in this review after applying the exclusion criteria. Due to its increasing prevalence worldwide in both humans and dogs, detecting and elucidating the pathogenicity of this parasite is paramount for effective global control and prevention of periodontal disease. However, there is a paucity in the literature on this neglected zoonotic trichomonad, which is in large contrast to the closely related human pathogen T. vaginalis. Here, we comprehensively review the history, morphology and reproduction, host, prevalence, diagnosis, pathogenicity, control, and prevention of T. tenax. Hopefully, this article will call attention to both medical and veterinary professionals as well as epidemiologists on this most neglected and zoonotic protozoan. More epidemiological and clinical studies need to be conducted on T. tenax to gain a better understanding of its pathogenicity, to increase the chances of developing effective drugs to aid in the control of this oral parasite, and reduce the spread of periodontal disease worldwide.

Trichomonas tenax induces barrier defects and modulates the inflammatory cytotoxicity of gingival and pulmonary epithelial cells

BACKGROUND

Trichomonas tenax is a single-cell flagellated anaerobic organism, commensal in the human oral cavity. Although a previous study indicated that T. tenax could cause cell damage and phagocytose host epithelial cells, its pathological effects on gum cells remain unknown. Furthermore, several case reports have detected T. tenax in several patients with empyema and/or pleural effusion, which may have been aspirated from the oral cavity. However, the cytotoxic effects and immune responses of alveolar cells are unknown. Therefore, we aimed to determine the cytotoxic and immune effects of T. tenax on gums and pulmonary cell lines. The cytopathic effect and lactate dehydrogenase (LDH) cytotoxicity assays were used to determine the level of cell damage in gum and lung epithelial cells. Western blot was used to determine the disruption of cell junctions. Finally, epithelial cell cytokines were measured using ELISA to elucidate the immune response to T. tenax.

RESULTS

We found that T. tenax induced a cytotoxic effect on gum epithelial cells by disrupting cell junctions; however, it hardly triggered cellular damage in alveolar A549 cells and mucoepidermoid NCI-H292 cells. Furthermore, T. tenax induced the production of IL-6 at a low multiplicity of infection (MOI) in gum, A549, and NCI-H292 cells.

CONCLUSIONS

Our results suggest that T. tenax can trigger gingival cell cytotoxicity, disrupt cell junctions, and induce IL-6 production in gingival and pulmonary cell lines.

Molecular prevalence and zoonotic potential of trichomonads from oral cavities in household dogs

This study investigated the molecular prevalence of oral trichomonads in household dogs. Of the 144 dogs, 21 (14.6%, 21/144) tested positive for oral trichomonads. The prevalence was significantly higher in dogs with severe gingivitis (gingival index 3: 30.0%, 8/26) than that in normal dogs (gingival index 0: 2.7%, 1/37). Therefore, an interaction between oral trichomonads and the development of periodontal disease is suggested. Of the 21 positive samples, 16 isolates were T. brixi, four isolates were T. tenax, and one was Tetratrichomonas sp. Considering T. tenax is recognized as a zoonotic agent, transmission between dogs and humans cannot be neglected.

Prevalence and risk factors of oral cavity parasites in pregnant women in Western Iran

Background

We aimed to study the frequency and risk factors of oral cavity protozoa (Trichomonas tenax and Entamoeba gingivalis) in pregnant women in Lorestan province, western Iran.

Methods

The current cross-sectional descriptive work was performed on 200 pregnant women referring to health centers of Lorestan Province, Iran during August 2021 to February 2022. Two specimens were obtained from each women by means of sterile swabs from saliva and dental plaques. The frequency of oral cavity protozoa was investigated using microscopic and conventional polymerase chain reaction (PCR).

Results

E. gingivalis and T. tenax parasites were found in 41 (20.5%) and 46 (23%) of the pregnant women by microscopic and PCR test, respectively. Among positive samples, 29 (63.1%) of the pregnant women were infected with E. gingivalis; whereas 19 (36.9%) of the participants were positive for T. tenax. In the multivariate model, living in rural regions (p < 0.001) and brushing teeth (p = 0.021) were considerably linked with the prevalence of oral cavity parasites.

Conclusion

The current study evidently exhibited the high frequency of oral cavity parasites (E. gingivalis and T. tenax) in pregnant women in Lorestan province, Western Iran. Awareness of the main risk factors for oral cavity parasites especially teeth brushing is necessary in refining public and oral health approaches in pregnant women. Thus, dental practitioners and gynecologists must be alert of these risk factors to carefully identify and manage oral health concerns in pregnant women to prevent the oral diseases and infections.

Cytokine array analysis of mediators produced by human macrophages stimulated with Trichomonastenax

The incidence of oral colonization by the protozoan Trichomonas tenax correlates with gingival inflammation and periodontitis in humans. To determine whether T. tenax might contribute to inflammation by eliciting cytokines from human cells, differentiated THP-1 (dTHP-1) macrophages were cultured with live or sonicated T. tenax trophozoites, and the conditioned media were assayed for 36 different mediators by a membrane-based cytokine array. Scanning densitometry of the membranes revealed that live T. tenax trophozoites stimulated secretion of interleukin-8 (IL-8), macrophage migration inhibitory factor (MIF), IL-1β, intercellular adhesion molecule-1 (ICAM-1), and IL-1 receptor antagonist (IL-1ra) from dTHP-1 macrophages. T. tenax lysates stimulated release of IL-8, MIF, and IL-1ra. Despite often being classified as a commensal organism, T. tenax elicited a wider variety of cytokines than the human urogenital pathogen, T. vaginalis, which elicited only IL-8 and MIF production from dTHP-1 cells.

Draft Genome Sequence of Trichomonas tenax Strain Hs-4:NIH

Trichomonas tenax is a flagellated parasite that plays an important role in periodontal disease, with high prevalence worldwide. Its pathogenesis remains largely unknown, and there is very little information on its genome. Here, we present the whole-genome shotgun sequence of T. tenax strain Hs-4:NIH.

A Loop-Mediated Isothermal Amplification (LAMP) Assay Specific to Trichomonas tenax Is Suitable for Use at Point-of-Care

Trichomonas tenax is a flagellated protozoan that inhabits the human and canine oral cavity in patients with poor oral hygiene and periodontal disease. The loop-mediated isothermal amplification (LAMP) assay could provide clinicians with a quick, cheap and reliable diagnostic test used for the detection of T. tenax in various settings. In this study, we aimed to develop a LAMP assay that can detect T. tenax with high sensitivity and specificity. A set of LAMP primers were specifically designed to detect the ITS and 5.8S rRNA gene of T. tenax. The newly developed LAMP assay was 1000 times more sensitive than conventional PCR. The limit of detection of the LAMP assay was 10 fg of genomic DNA, or 0.2-1 cell. Moreover, the LAMP assay was specific, resulting in no cross-reaction even with a closely related protozoan T. vaginalis or other microorganisms (Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, and Candida albicans) used. The present LAMP assay can be performed directly without prior DNA extraction, making the assay an easy, fast, cheap, specific and sensitive diagnostic tool for the detection of T. tenax at the point-of-care of both medical and veterinary clinics in developed and developing countries.

Global prevalence and epidemiology of Strongyloides stercoralis in dogs: a systematic review and meta-analysis

BACKGROUND

Strongyloides stercoralis, a soil-transmitted helminth, occurs in humans, non-human primates, dogs, cats and wild canids. The zoonotic potential between these hosts is not well understood with data available on prevalence primarily focused on humans. To increase knowledge on prevalence, this review and meta-analysis was performed to estimate the global status of S. stercoralis infections in dogs.

METHODS

Following the PRISMA guidelines, online literature published prior to November 2020 was obtained from multiple databases (Science Direct, Web of Science, PubMed, Scopus and Google Scholar). Prevalence was calculated on a global and country level, by country income and climate, and in stray/animal shelter dogs versus owned dogs. Statistical analyses were conducted using R-software (version 3.6.1).

RESULTS

From 9428 articles, 61 met the inclusion criteria. The estimated pooled global prevalence of S. stercoralis in dogs was 6% (95% CI 3-9%). Infection was found to be the most prevalent in low-income countries with pooled prevalence of 22% (95% CI 10-36%). The highest pooled prevalence of S. stercoralis in dogs was related to regions with average temperature of 10-20 °C (6%; 95% CI 3-11%), an annual rainfall of 1001-1500 mm (9%; 95% CI 4-15%) and humidity of 40-75% (8%; 95% CI 4-13%). Prevalence was higher in stray and shelter dogs (11%; 95% CI 1-26%) than in owned dogs (3%; 95% CI 1-7%).

CONCLUSIONS

As with S. stercoralis in humans, higher prevalence in dogs is found in subtropical and tropical regions and lower-income countries, locations which also can have high dog populations. While this study presents the first estimated global prevalence of S. stercoralis in dogs, it is potentially an underestimation with 15 of 61 studies relying on diagnostic methods of lower sensitivity and a paucity of data from most locations. Standardized protocols (e.g. quantity of feces and number of samples for a Baermann) in future studies could improve reliability of results. More prevalence studies and raising veterinary awareness of S. stercoralis are needed for a One Health approach to protect humans and dogs from the impact of the infection.

Oral cavity protozoa relevant in the practice of dentistry

Introduction: Oral cavity is the colonization site of most diverse microorganisms. The homeostasis of oral microbioma is affected by numerous factors. Periodontal diseases occur as a consequence of disturbed oral microbioma homeostasis, when an inflammatory reaction occurs in the periodontal tissue. The impact of parasites on periodontal pathophysiology has not been sufficiently studied, and present and future research should hopefully answer quite a few questions concerning the issue. Aim of the paper: In the light of the present knowledge of the pathogenesis, diagnosis and epidemiology of oral cavity infections caused by Entamoeba gingivalis and Trichomonas tenax, the aim of the paper was review of literature which could to point to the importance of protozoa in the practice of dentistry and to possible oral cavity manifestations of parasitic infections relevant for public health. Conclusion: Dentists have an essential role in the diagnosis of oral diseases caused by oral cavity protozoa, and protozoa relevant for public health that produce systemic infections, the pathological changes of which may manifest in the oral cavity. Their identification represents a challenge and requires multidisciplinary approach for a timely diagnosis and adequate management.

Oral Colonization by Entamoeba gingivalis and Trichomonas tenax: A PCR-Based Study in Health, Gingivitis, and Periodontitis

Background

The etiology of periodontitis remains unclear, as is the place of gingivitis in its pathophysiology. A few studies linked the colonization by oral parasites (Entamoeba gingivalis and Trichomonas tenax) to periodontal disease and its severity. The aim of the current study was to estimate the prevalence of these oral parasites among healthy individuals, and in patients with gingivitis and periodontitis in Jordan.

Methods

The study was conducted during July 2019–December 2019. Samples were composed of saliva and periodontal material including dental plaque sampled with probes. The detection of oral parasites was done using conventional polymerase chain reaction (PCR).

Results

The total number of study participants was 237: healthy (n=94), gingivitis (n=53) and periodontitis (n=90). The prevalence of E. gingivalis was 88.9% among the periodontitis patients, 84.9% among the gingivitis patients and 47.9% in the healthy group. For T. tenax, the prevalence was 25.6% among the periodontitis patients, 5.7% among the gingivitis patients and 3.2% in the heathy group. Positivity for E. gingivalis was significantly correlated with the presence of periodontal disease compared to the healthy group with odds ratio (OR) of 6.6. Periodontal disease was also correlated with lower monthly income (OR=8.2), lack of dental care (OR=4.8), and history of diabetes mellitus (OR=4.5). Colonization by E. gingivalis was correlated with gingivitis (OR=6.1) compared to the healthy group. Colonization by E. gingivalis and T. tenax were significantly correlated with periodontitis (OR=6.4 for E. gingivalis, and OR=4.7, for T. tenax) compared to the healthy group. T. tenax was only detected among individuals with generalized periodontal disease compared to its total absence among those with localized disease (19.6% vs. 0.0%; p=0.039). The co-infection rate by the two oral parasites was 11.0%.

Conclusions

The higher prevalence of human oral parasites in periodontal disease compared to healthy individuals appears to be more than a mere marker for the disease and might also be associated with disease severity and potential for progression. Thus, the dogmatic view of E. gingivalis and T. tenax as commensals needs to be re-evaluated and their contribution to pathophysiology of periodontal diseases cannot be neglected.

Current Global Status and the Epidemiology of Entamoeba gingivalis in Humans: A Systematic Review and Meta-analysis

PURPOSE

Entamoeba gingivalis (E. gingivalis) is one of the members of the wide range of oral resident pathogens in humans, particularly found in dental plaques, surfaces of gingiva or teeth, interdental spaces and carious lesions. The purpose of the current review and meta-analysis was to determine the global prevalence of E. gingivalis infection and its association with oral diseases based on published literatures.

MATERIALS AND METHODS

Multiple English databases (PubMed, Scopus, Science Direct, Web of Science and Google Scholar) were explored for papers published until August 2020. A total of 52 studies (including 7596 participants) met the inclusion criteria.

RESULTS

The overall prevalence of E. gingivalis was estimated to be 37% (95% CI 29-46%). With regard to different countries, the highest and lowest pooled prevalence of E. gingivalis infection were related to Jordan with 87% (95% CI 81-92%) and Portugal with 3% (95% CI 0-10%), respectively. Based on WHO regions, the highest prevalence was related to the region of the Americas with 56% (95% CI 31-79%). The infection was most prevalent in 46-55 mean age groups [61% (95% CI 21-94%)]. Among different diagnostic methods, the highest rate of the pooled prevalence was related to the molecular [53% (95% CI 24-81%)] and the direct methods [36% (95% CI 25-47%)], respectively. Our analyses revealed that E. gingivalis infection was associated with 4.34-fold increased risk of oral diseases (P < 0.05).

CONCLUSION

Our findings revealed a high prevalence rate of the infection among periodontal disease patients with 37% (95% CI 20-57%). To conclude, it must be considered that E. gingivalis can be a risk factor associated with oral diseases and a wide range of research is needed to specify its role in the pathogenesis of these disorders.

Parasites in surgically removed appendices as a neglected public health concern: a systematic review and meta-analysis

The role of various parasitic infections in the occurrence of appendicitis is illustrated through cases recorded all over the world. The purpose of the current study was to estimate the global prevalence of parasite infestation (other than E. vermicularis) in appendectomy specimens.In the setting of the PRISMA guidelines, multiple databases (Science Direct, Scopus, Web of Science, PubMed, and Google Scholar) were explored in articles published until 28 September 2020. Totally, 62 studies (106 datasets) with 77, 619 participants were included in the analysis.The pooled prevalence of parasites in appendectomy samples was as follows; 0.012% (95% CI; 0.004-0.025) for Ascaris lumbricoides, 0.004% (95% CI; 0.001-0.009) for Trichuris trichiura, 0.025% (95% CI; 0.007-0.052) for Schistosoma mansoni, 0.002% (95% CI; 0.001-0.005) for Taenia spp., 0.061% (95% CI; 0.020-0.122) for Entamoeba histolytica and 0.034% (95% CI; 0.018-0.056) for Giardia lamblia.Our results demonstrated that the risk of appendicitis may increase in the presence of helminth and protozoan infections. As such, the most cases of parasites in appendectomy specimens were reported in developing countries. Regular screening plans for diagnosis, treatment and prevention are needed for prevention of parasitic infection as well as parasitic associated appendicitis, especially in endemic regions of the world.

Deciphering the toxicological role of Porphyromonas gingivalis derived endotoxins in liver diseases

Periodontitis is a most prevalent and infectious multifactorial inflammatory disease and is characterized by the progressive destruction of the tooth-supporting tissues. Porphyromonas gingivalis, a Gram‑negative oral anaerobe, mainly causes periodontitis and it is one of the most important risk factors responsible for aggravation of existing systemic diseases. Several experimental and clinical studies have shown the positive association between periodontitis and different forms of liver disease. Periodontal diseases increase the prevalence of non-alcoholic fatty liver diseases and cirrhosis. Infected periodontium and pathogens in the periodontal microenvironments release pathogen-associated molecular patterns such as peptidoglycan, lipopolysaccharides, gingipain, fimbria, bacterial DNA, etc, and damage-associated molecular patterns such as interleukins-1α, β, - 8, and galectin-3, etc. These virulence factors and cytokines enter the bloodstream, disseminate into the whole body, and induce a variety of systemic pathological effects, including liver diseases (steatosis and fibrosis). Maintaining oral hygiene by scaling and root planning significantly improves liver damage in patients with periodontitis. Dentists and physicians should have more awareness in understanding the bidirectional nature of the relationship between oral and systemic diseases. Importantly, periodontitis condition aggravates simple fatty liver into fibrotic disease and therefore, the aim of this review is to understand the possible link between periodontitis and liver diseases.

Prevalence of Strongyloides stercoralis in the immunocompetent and immunocompromised individuals in Iran: a systematic review and meta-analysis

Strongyloidiasis is a neglected tropical disease mostly distributed in tropical and subtropical regions. The current study evaluated the prevalence of Strongyloides stercoralis in immunocompetent and immunodeficient patients in Iran. The available online literature published from June 1994 to October 2020 was obtained from multiple English databases (PubMed, Science Direct, Scopus, Web of Science and Google Scholar) and four Persian databases (Magiran, Iran Medex, Iran Doc and SID). All statistical analyses were performed using R software (version 3.6) meta-package and p-values <0.05 were considered significant. From 1051 articles, 74 studies (248 656 individuals) met the inclusion criteria. The pooled prevalence of S. stercoralis was 2% (95% confidence interval [CI] 1 to 3) and 4% (95% CI 1 to 8) in immunocompetent and immunodeficient patients, respectively. In immunodeficient cases, the pooled prevalence of studies utilizing serology, culture and microscopic methods was 10% (95% CI 2 to 23), 1% (95% CI 0 to 6) and 1% (95% CI 0 to 1), respectively. In immunocompetent cases, the pooled prevalence of studies utilizing microscopic, culture and molecular methods was 2% (95% CI 1 to 3), 2% (95% CI 1 to 4) and 2% (95% CI 0 to 6), respectively. We propose an appropriate screening and control program along with comprehensive research regarding the frequency of strongyloidiasis in the country.

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.