Search Results (220)

Background: Genital tract infections and dysbiosis-related conditions contribute substantially to women’s sexual and reproductive morbidity. In South America, evidence on clinically relevant genital microorganisms remains fragmented across countries, populations, and diagnostic approaches. This systematic review and meta-analysis synthesized the prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Gardnerella vaginalis, and Candida spp. among women in South America. Methods: We searched PubMed/MEDLINE, Web of Science, Cochrane Library, and SciELO for studies published from 1 January 2014 to 29 February 2024. Eligible studies reported prevalence data for at least one target microorganism in female populations from South American countries. Two reviewers independently screened studies, extracted data, and assessed methodological quality using Joanna Briggs Institute criteria for prevalence studies. Crude prevalence and random-effects pooled prevalence estimates with 95% confidence intervals were calculated. The review protocol was registered in PROSPERO (CRD420261324060). Results: Of 629 records identified, 51 studies from eight South American countries and French Guiana met the eligibility criteria for the systematic review, and 46 contributed to the main pooled prevalence meta-analysis. Substantial between-study heterogeneity was observed across all pathogen-specific analyses. Pooled prevalence was highest for G. vaginalis (28%), followed by Candida spp. (12%), C. trachomatis (7%), T. vaginalis (6%), and N. gonorrhoeae (3.2%). Conclusions: This review highlights the heterogeneous burden of clinically relevant genital microorganisms among women in South America and supports standardized diagnostic approaches, clearer phenotypic definitions, and stronger surveillance across underrepresented regional settings. Full article

Neisseria gonorrhoeae is a major sexually transmitted pathogen and global public health concern. A porA pseudogene-targeting TaqMan quantitative PCR (qPCR) assay was evaluated as a complementary laboratory-based method for the qualitative detection of N. gonorrhoeae and exploratory Z017-calibrated molecular estimation in cultured reference strains. Two candidate probe sets were evaluated, and the probe set generating a 157 bp amplicon was selected for a defined two-step qPCR workflow with a 52 min on-instrument amplification runtime. In silico analysis showed compatible target site arrangements in all 201 N. gonorrhoeae genomes and none in 114 non-target organisms. The assay detected N. gonorrhoeae DNA down to 1 × 10⁻⁵ ng/µL, with no amplification of the tested non-target organisms. All 23 N. gonorrhoeae reference strains and 80 N. gonorrhoeae-positive clinical specimens were detected, whereas no amplification was observed in the 20 negative clinical specimens, using DNA extracted from the primary clinical specimens. A standard curve was generated from the titered Z017 reference material (R² = 0.999; efficiency, 94.6%), which enabled reproducible qPCR-derived CFU/mL-equivalent molecular estimation in cultured World Health Organization reference strains. The qPCR-derived estimates were lower than the paired culture-derived CFU/mL values, and the paired log10-transformed values did not show a statistically significant correlation. These findings provide an assay design and validation-oriented laboratory-based framework combining in silico sequence assessment, the qualitative detection of N. gonorrhoeae in clinical specimens, and exploratory molecular estimation in cultured reference strains, supporting future assay development and bacterial burden research. Full article

Infectious diseases remain a major global public health concern, disproportionately causing morbidity and mortality in low- and middle-income countries. Sexually Transmitted Infections (STIs) heavily affect sexually active populations. Sex workers, encompassing female sex workers (FSWs), male sex workers (MSWs), and transgender/gender-diverse individuals, face heightened vulnerabilities due to occupational exposures, structural barriers, stigma, and criminalization. While substantial focus has historically centered on HIV, non-HIV STIs such as Neisseria gonorrhoeae, Chlamydia trachomatis, Treponema pallidum, and viral hepatitis present significant co-morbidity. Crucially, drug resistance across these pathogens presents distinct biological and epidemiological challenges: bacterial antimicrobial resistance (AMR) in N. gonorrhoeae and C. trachomatis, antiretroviral (ARV) resistance in HIV, and direct-acting antiviral (DAA) resistance in hepatitis B and C. This perspective article synthesizes the current epidemiological landscape, critiques the reliance on syndromic management over molecular diagnostics (e.g., NAATs, point-of-care, and genomic surveillance), highlights diagnostic stewardship, and outlines priority public health strategies aligned with the WHO 2022–2030 Global Health Sector Strategies. Full article

In contrast to honeybees, the Australian stingless bee Tetragonula carbonaria appears to be robust against microbial pathogens. Streptomyces sp. 127Q, isolated from T. carbonaria, inhibited the growth of Lysinibacillus sphaericus, which is the only microorganism reported to affect T. carbonaria. The antimicrobials were purified from Streptomyces sp. 127Q by bioassay-guided isolation using ethyl acetate extraction and Diaion HP20 chromatography, followed by reverse phase HPLC fractionation. The antimicrobial compounds were identified by high-resolution mass spectrometry, UV-Vis-spectroscopy, nuclear magnetic resonance spectroscopy, and genome mining as new members of the trioxacarcin/gutingimycin family having a 1,2-dihydroxyanthraquinone aromatic core structure. A closely related gutingimycin with a 1,2-dihydroxyanthraquinone moiety was previously observed in a crystallisation experiment of trioxacarcin A with an oligonucleotide. Streptomyces sp. 127Q produces a wide range of trioxacarcins/gutingimycins. At the onset of trioxacarcins production, Streptomyces sp. 127Q appeared to rapidly convert trioxacarcin epoxides with water, guanine, and nicotinic acid. The 1,2-dihydroxyanthraquinone trioxacarcins, trioxacarcin 692 and trioxacarcin 780, inhibited L. sphaericus with minimal inhibitory concentrations (MICs) of 37.5 μM and 75 μM, respectively. The MIC against Escherichia coli and Staphylococcus aureus was 75 μM and 150 μM, respectively. In the photoantimicrobial screening, the MIC for trioxacarcin 692 against E. coli and S. aureus decreased by 8-fold, and for trioxacarcin 780 by 4-fold. Following light pretreatment, trioxacarcin 692 (9.4 μM) inhibited E. coli and S. aureus at concentrations comparable to those of the established antibiotics ciprofloxacin and vancomycin. Neisseria gonorrhoeae was only inhibited at an MIC of ca. 18.8 μM after light preincubation. The 1,2-dihydroxyanthraquinone trioxacarcins constitute powerful antimicrobial compounds belonging to the trioxacarcin/gutingimycin family. Full article

Background and Objectives: Antimicrobial resistance in Neisseria gonorrheae threatens the effectiveness of empirical gonorrhoea treatment. Although global surveillance evidence is increasingly available, resistance data are not consistently reported separately for men with urethral or urogenital infection. This review evaluated antibiotic-specific resistance in N. gonorrhoeae isolates from this clinically defined population and examined the geographic and reporting limitations of the available evidence. Materials and Methods: PubMed, Scopus, ScienceDirect, Google Scholar, and relevant WHO GASP/EGASP resources were searched from inception to [updated search date]. Eligible observational or surveillance studies reported categorical resistance classifications or extractable antibiotic-specific resistant counts and denominators for male urethral or urogenital isolates. Antibiotic-specific proportions were synthesized using random-effects meta-analysis where pooling was considered appropriate. Sparse-event outcomes were additionally evaluated using study-specific estimates and aggregate resistant/tested counts. Certainty of evidence was assessed using the GRADE framework adapted for prevalence outcomes. Results: Six studies met the eligibility criteria, including the 2025 multinational EGASP study. Cefixime resistance was reported in 748 of 13,154 isolates, corresponding to an aggregate proportion of 5.69%; however, the random-effects estimate was unstable because three studies reported no resistant isolates and events were concentrated in two large datasets. Ceftriaxone resistance varied from 0% to 5.17%, with a pooled estimate of 0.32% (95% CI 0.05–2.15; I² = 97.8%). Resistance was high but heterogeneous for ciprofloxacin (71.84%, 95% CI 7.53–98.77; I² = 97.3%) and penicillin (62.47%, 95% CI 36.87–82.58; I² = 98.1%). Spectinomycin resistance was 2.57% (95% CI 1.58–4.16; I² = 0%), while azithromycin resistance was 6.38% (95% CI 4.38–9.21; I² = 94.9%). Certainty of evidence was very low for all outcomes. Conclusions: Evidence specifically reporting resistance in male urethral or urogenital N. gonorrhoeae isolates remains limited and geographically uneven. Contemporary EGASP data demonstrate that ceftriaxone resistance is not uniformly low across surveillance settings. The pooled estimates should be interpreted as exploratory summaries rather than current global prevalence values or an independent basis for treatment selection. Standardized reporting of sex, anatomical site, breakpoints, MIC distributions, and resistant/tested counts is needed to improve future surveillance synthesis. Full article

Sexually transmitted infections remain a major public health concern among men who have sex with men (MSM), particularly due to the high frequency of coinfections and the limitations of syndromic management. This study aimed to describe the frequency of bacterial sexually transmitted and urogenital pathogens among symptomatic MSM attending two specialized sexual health clinics in Mexico City. A prospective cross-sectional study was conducted with 150 adult MSM presenting symptoms suggestive of urethritis. Urethral swab samples were analyzed using a multiplex real-time polymerase chain reaction (PCR) assay for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, Ureaplasma parvum, and Trichomonas vaginalis. At least one pathogen was detected in 91/150 participants (60.7%). N. gonorrhoeae was the most frequent pathogen (33.3%), followed by U. urealyticum (15.3%), M. genitalium (9.3%), and C. trachomatis (9.3%). Coinfections were identified in 15 participants, representing 10.0% of the total population and 16.5% of those with a positive PCR result. Most coinfections involved N. gonorrhoeae, particularly with C. trachomatis. These findings provide descriptive microbiological evidence on the frequency and coinfection patterns of bacterial sexually transmitted infections (STIs) associated pathogens among symptomatic MSM attending specialized sexual health clinics in Mexico City. The high detection rate and occurrence of concurrent infections highlight the limitations of syndromic management and support the value of timely multiplex molecular diagnostics to improve etiological characterization, antimicrobial stewardship, and clinical decision-making in this population. Full article

Antimicrobial resistance in Neisseria gonorrhoeae is a global concern. Spectinomycin is unusual in that resistance can emerge rapidly during localized outbreaks yet often disappears from clinical populations after drug withdrawal, suggesting an associated growth cost. To investigate evolutionary routes to spectinomycin resistance, we performed in vitro selection on two N. gonorrhoeae strains and two commensal Neisseria species. Derived cell lines were characterized by minimum inhibitory concentration (MIC) determination, whole-genome sequencing, growth-kinetics analysis, and molecular modelling of the RpsE (ribosomal protein S5) interface with the ribosome. All high-level resistant isolates (MIC > 2048 mg/L) acquired substitutions or deletions in loop 2 of RpsE. Modelling showed that these mutations perturb the conserved network of stabilizing contacts between RpsE residues Lys25 (Lys23 in E. coli numbering) and Lys28 (Lys26), as well as helix 34 nucleotides G922, A923, and C1069 of 16S rRNA, potentially altering the architecture of the spectinomycin-binding site. These mutations were associated with high-level resistance but reduced growth rates, with the resulting growth costs depending on the specific pattern of contact rearrangements. Convergent evolution towards loop 2 mutations supports the existence of a constrained mutational pathway to high-level spectinomycin resistance in the strains and species examined here. This constraint may help explain the rapid decline of resistant variants in the absence of drug pressure and underscores the importance of genomic surveillance. Full article

Sample adequacy control (SAC) is a validated specimen-specific marker or metric, threshold, and reporting rule used to decide whether a negative molecular result is supported by the submitted specimen. SAC is not simply a cell-count or biomass check. Depending on specimen type and target, an unsupported negative result may reflect insufficient or nonrepresentative material, adequacy-marker degradation, inefficient transfer or extraction, matrix-associated inhibition, or mismatch between marker and anatomical compartment. SAC is therefore best understood as an integrated specimen-process adequacy control for negative-result interpretation. Its result should be reported as valid, borderline, or invalid for the intended negative interpretation, not as detected/not detected like the disease-specific biomarker. This perspective synthesizes quantitative polymerase chain reaction (qPCR) control guidance, preanalytical-quality literature, respiratory and enteric sampling studies, human papillomavirus (HPV) evidence, cartridge-assay precedents, and decentralized workflows. Direct prospective evidence that SAC improves patient or epidemiologic outcomes remains limited; available evidence is outcome-adjacent or operational, including HPV cellularity-control associations, Chlamydia trachomatis/Neisseria gonorrhoeae (CT/NG) and Ebola cartridge precedents, respiratory workflows showing lower pathogen positivity at higher SAC quantification cycle (Cq) strata, and reporting rules that change validity or recollection decisions. We propose a risk-based framework for selecting, validating, reporting, and monitoring SAC, with particular value in direct-amplification, point-of-care, and self-collection workflows where preanalytical failures affect negative-result interpretation. Full article

Background/Objectives: Neisseria gonorrhoeae is a high-priority pathogen for the development of new therapeutic alternatives. Efflux pumps are attractive drug targets because their inactivation influences N. gonorrhoeae susceptibility to multiple antimicrobials. Since most gonococcal efflux systems are energy-dependent, interference with energy metabolism and membrane transport may indirectly compromise efflux activity. Efflux inhibitors may increase intracellular antibiotic concentration, although this requires validation in resistant strains. The most effective efflux inhibitors interfere with energy metabolism, affecting several physiological processes, including efflux. In this work, we used an in silico drug repurposing strategy targeting proteins involved in membrane transport and energy metabolism in N. gonorrhoeae. A subset of candidate drugs were subsequently evaluated in vitro using only the reference strain N. gonorrhoeae ATCC 49226. Methods: Predicted drug–target interactions were identified using publicly available databases such as DrugBank and STITCH. Minimum inhibitory concentrations (MICs) of selected drugs against N. gonorrhoeae were determined by microdilution. Changes in intracellular ethidium bromide accumulation were assessed by real-time fluorometry as an indirect indicator of possible efflux-related interference. Results: In silico analysis identified 32 predicted targets associated with 57 approved drugs. Triclabendazole and dequalinium showed the lowest MIC values of the tested compounds (2 and 4 mg/L, respectively). Ketotifen and verapamil demonstrated activity consistent with possible efflux interference, as indicated by increased ethidium bromide accumulation. Atovaquone showed adjuvant-like effects in combination assays, suggesting that mechanisms other than efflux-related interference may contribute to its activity. Conclusions: Overall, this preliminary study identifies approved drugs with antimicrobial or adjuvant activity against a single N. gonorrhoeae reference strain, supporting further investigation in clinically relevant and efflux-variant strains. Full article

Background: Invasive meningococcal disease (IMD) remains a rare but severe condition associated with high mortality and a significant risk of long-term sequelae. Despite global vaccination efforts, the epidemiology of Neisseria meningitidis continues to evolve, with serogroup B (MenB) representing the predominant cause of IMD in many high-income countries. Methods: This consensus document reviews current evidence on MenB epidemiology and the role of the multicomponent meningococcal serogroup B vaccine (4CMenB), with a focus on immunogenicity, strain coverage, real-world effectiveness, and remaining challenges. Results: Protein-based MenB vaccines have overcome the limitations of polysaccharide approaches, demonstrating robust immunogenicity across age groups. Real-world data confirm substantial vaccine effectiveness, particularly in infant immunization programs and outbreak settings, with significant reductions in disease incidence. For example, in England in the 3 years after vaccine introduction, MenB IMD incidence declined by 75% in immunized infants compared to unvaccinated controls. Adjusted vaccine efficacy was 52.7% after the two-dose primary series and 59.1% following the booster dose, highlighting the contribution of the booster. However, protection is influenced by antigenic variability among circulating strains, resulting in incomplete and geographically variable coverage. In addition, antibody waning over time and the limited impact on nasopharyngeal carriage reduce the potential for long-term and indirect protection. These factors highlight the need to optimize vaccination strategies, including the timing of booster doses, particularly in adolescents, and the role of vaccination in different epidemiological contexts. In this regard, it is not precisely defined whether infants who were immunized in the first year of life need a booster dose in the preschool period, especially in countries with a high incidence of MenB disease. Moreover, it is not established whether and when adolescents who were vaccinated both in infancy and during the preschool period need a booster dose. Economic considerations and variability in national immunization policies further contribute to heterogeneity in vaccine implementation. Emerging evidence suggests possible cross-protection against other meningococcal serogroups and Neisseria gonorrhoeae, although findings remain inconsistent across different risk groups and do not allow us to recommend 4CMenB vaccine beyond MenB IBD prevention. Conclusions: 4CMenB is an effective tool for preventing MenB IMD, although further studies are needed. Future strategies should prioritize age-targeted boosting and enhanced genomic surveillance to maximize impact. Full article

Bacterial sexually transmitted and sexually associated infections remain a major global health concern, increasingly complicated by antimicrobial resistance and the limited effectiveness of existing therapies. In this context, bacteriophage-based and phage-derived approaches have re-emerged as potential alternative antibacterial strategies. This narrative review examines their applicability across key bacterial pathogens associated with sexually transmitted infections, including Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Treponema pallidum and biofilm-associated bacterial vaginosis, with a particular focus on pathogen-specific biological barriers. Available evidence indicates that the success of phage-based interventions is strongly dependent on factors such as intracellular localisation, structural characteristics of the bacterial envelope and the presence of polymicrobial biofilms. While phage-derived platforms, including endolysins, depolymerases and engineered phages, demonstrate antibacterial activity in experimental settings, their effectiveness is uneven across different pathogens. Biofilm-associated infections appear more accessible to these approaches, whereas intracellular and structurally atypical bacteria are currently considered more challenging targets based on available mechanistic and experimental evidence. These observations highlight the need for pathogen-specific engineering strategies and delivery systems. Overall, phage-based therapeutics in this field should be considered within a framework that integrates biological constraints with targeted antimicrobial design. Full article

Background/Objectives: Mycoplasma genitalium is an emerging cause of sexually transmitted infections (STIs) and is increasingly recognized for its association with cervicitis and pelvic inflammatory disease. However, prevalence data in specific Japanese subpopulations, particularly comparing pregnant and non-pregnant women, remains limited. This study aimed to determine the prevalence of M. genitalium and its co-infection rates with Chlamydia trachomatis and Neisseria gonorrhoeae among Japanese women. Methods: A cross-sectional study was conducted using vaginal swab specimens collected between April 2021 and November 2022 from patients visiting two clinics in Gifu, Japan. The study population comprised 2138 non-pregnant women presenting with urogenital symptoms or sexual contact history, and 236 pregnant women undergoing routine antenatal screening. Detection was performed using real-time polymerase chain reaction assays on the cobas^® 8800 system (Roche Diagnostics). Results: Among non-pregnant women, the overall prevalence was 3.8% (82/2138) for M. genitalium, 3.4% (72/2138) for C. trachomatis, and 0.4% (9/2138) for N. gonorrhoeae. Co-infection rates were low; M. genitalium and C. trachomatis co-infection was observed in 0.2% of cases. Among pregnant women, the prevalence was 3.8% (9/236) for both M. genitalium and C. trachomatis, and 0.4% (1/236) for N. gonorrhoeae. No statistically significant differences in prevalence were observed between pregnant and non-pregnant women for any pathogen. Conclusions: The prevalence of M. genitalium in this Japanese cohort was comparable to that of C. trachomatis in both pregnant and non-pregnant women, highlighting its significance as a major STI pathogen. These findings underscore the importance of including M. genitalium in routine STI screening panels for symptomatic women and antenatal care to prevent reproductive health complications. Given the high rates of antimicrobial resistance documented in Japanese M. genitalium strains, specific diagnostic testing is essential to enable targeted, resistance-guided therapy. Full article

Introduction: Neisseria gonorrhoeae, a bacterium responsible for gonorrhea, can spread through oral sex, causing pharyngeal gonorrhea, which is also a leading cause of urethritis in outpatient clinics. This study investigated whether tea tree oil (TTO) alone or in combination with other natural products could serve as an effective alternative to chlorhexidine in preventing the spread of oral gonorrhea. Methods: An in vitro model was developed using T84 epithelial cells as a mucosal layer and Neisseria gonorrhoeae strain MS11. The study assessed the minimal inhibitory concentration (MIC), bacterial adherence, invasion, and transmigration across the mucosal barrier. Berberine (BB), a major and bioactive alkaloid derived from Coptis chinensis, was tested with and without TTO in MIC assays and epithelial cell viability tests. Ceftriaxone was used as a positive control. Results: The MIC values for TTO, BB, and ceftriaxone against the MS11 strain were determined to be 0.2%, 5 μg/mL, and 0.0125 μg/mL, respectively. Notably, the combination of TTO with BB demonstrated a synergistic effect, reducing the MIC to 0.000625% TTO + 1.25 μg/mL BB. This combination provided the strongest protective effect. No cytotoxicity was observed in the epithelial cell viability tests for 0.2% diluted TTO, 5 μg/mL BB, or the combination of 0.000625% TTO + 1.25 μg/mL BB. Conclusions: BB, when combined with TTO, exhibited a synergistic antimicrobial effect against Neisseria gonorrhoeae strain MS11 in the T84 mucosal model. These findings highlight the potential of this combination as a natural alternative to chlorhexidine gluconate for managing oral gonorrhea. Full article

Background: Epididymo-orchitis can be caused by sexually transmitted pathogens, including Neisseria gonorrhoeae, Chlamydia trachomatis, and Mycoplasma genitalium, or entero-bacteria. The aim of this study was to explore the demographics, microbiological findings, and treatment outcomes of patients presenting to a tertiary sexual health clinic with epididymo-orchitis. Methods: We reviewed the clinical notes of 200 randomly selected patients seen in the clinic with a diagnosis of epididymo-orchitis between 2021 and 2025. We extracted data on demographics, microbiological findings, follow-up, and clinical response rate to treatment. Results: The median age was 33 years (Interquartile range (IQR) = 24–44), 97 (49%) identified as MSM, 11 (6%) were living with HIV (all MSM), and 55 out of the 86 HIV-negative MSM (64%) were using HIV pre-exposure prophylaxis. In total, 35 (18%, 95% confidence intervals = 12.5–23.5%) people were diagnosed with a causative organism: 17 (9%) C. trachomatis, 10 (5%) N. gonorrhoeae, 7 (4%) M. genitalium, 3 (2%) Escherichia coli. Overall, 91 out of 200 (46%) had a documented partner notification plan. Conclusions: A minority of men attending our sexually transmitted infection clinic with clinical epididymo-orchitis have positive microbiology, including M. genitalium. More work is needed to understand the clinical pathophysiology of epididymo-orchitis to streamline treatment algorithms. Full article

Background: Bacterial vaginosis and vaginal dysbiosis represent major causes of morbidity among women in sub-Saharan Africa, yet data from Madagascar remain scarce. This study aimed to assess the prevalence and determinants of vaginal bacterial infections among women in northern Madagascar and to explore how vaginal microflora composition reflects broader aspects of reproductive health. Methods: A cross-sectional study was conducted in April 2024 among 159 women (15–80 years) attending a rural second-referral clinic in Manerinerina, Ambatoboeny District. Sociodemographic and hygiene data were obtained through structured questionnaires. Vaginal pH was measured in situ, and Gram-stained smears were evaluated using the Nugent scoring system. The presence of Trichomonas vaginalis, Neisseria gonorrhoeae, and Candida spp. was assessed microscopically. Associations were analyzed using Chi-square or Fisher’s exact tests, with p < 0.05 considered significant. Results: Abnormal vaginal flora was observed in 68.6% of women, including 43.4% with BV (Nugent 7–10) and 25.2% with intermediate flora. Elevated vaginal pH correlated strongly with higher Nugent scores (p < 0.01). T. vaginalis and N. gonorrhoeae were detected in 10.7% and 9.4% of women, respectively, and both were significantly associated with dysbiosis (p = 0.02 and p = 0.04). Poor hygiene practices, vaginal douching (79.1% vs. 64.5%; p = 0.04), and unsafe water sources (p = 0.04) were major behavioral and environmental determinants. Conclusions: Vaginal dysbiosis is highly prevalent among women in northern Madagascar and closely linked to modifiable hygiene behaviors and environmental conditions. In resource-limited settings, Gram-stained microscopy and Nugent scoring remain cost-effective tools for surveillance and patient care. Culturally adapted education, improved water access, and integration of low-cost diagnostics are essential for reducing the burden of vaginal infections in rural Madagascar. Full article