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Abstract Background Genital infection with Chlamydia trachomatis (C. trachomatis) is a major public health issue worldwide. It can lead to cervicitis, urethritis, and infertility. This study was conducted to determine the characteristics of genital C. trachomatis infection among women attending to the infertility and gynecology clinics. Methods Endocervical swabs were collected from 8,221 women for C. trachomatis nucleotide screening and genotyping, while serum samples were collected for C. trachomatis pgp3 antibody determination using luciferase immunosorbent assays. Results High C. trachomatis DNA prevalence (3.76%) and seroprevalence (47.46%) rates were found, with genotype E (27.5%) being the most prevalent. C. trachomatis omp1 sense mutation was associated with cervical intraepithelial neoplasia (CIN) (odds ratio [OR] = 6.033, 95% confidence interval [CI] = 1.219–39.185, p = 0.045). No significant differences in C. trachomatis seroprevalence rates were observed between women with detectable C. trachomatis DNA in the infertility and routine physical examination groups (86.67% vs. 95%, p > 0.05); however, among women with negative C. trachomatis DNA, the former group had a markedly higher seroprevalence than the latter group (56.74% vs. 20.17%, p

Chlamydia trachomatis is a clinically important bacterium that infects epithelial cells of the genitourinary and respiratory tracts and the eye. These differentiated cells are in a quiescent growth state and have a surface organelle called a primary cilium, but the standard Chlamydia cell culture infection model uses cycling cells that lack primary cilia. To investigate if these differences are relevant, we performed infections with host cells that have a primary cilium. We found that C. trachomatis caused progressive loss of the primary cilium that was prevented by disrupting Aurora A (AurA), HDAC6 or calmodulin, which are components of the cellular cilia disassembly pathway. Stabilization of the primary cilium by targeting this pathway caused a large reduction in infectious progeny although there were no changes in chlamydial inclusion growth, chlamydial replication or the ultrastructural appearance of dividing and infectious forms (RBs and EBs, respectively). Thus, the presence of a primary cilium interfered with the production of infectious EBs at a late step in the developmental cycle. C. trachomatis infection also induced quiescent cells to re-enter the cell cycle, as detected by EdU incorporation in S-phase, and Chlamydia-induced cilia disassembly was necessary for cell cycle re-entry. This study therefore describes a novel host-pathogen interaction in which the primary cilium limits a productive Chlamydia infection, and the bacterium counteracts this host cell defense by activating the cellular cilia disassembly pathway. Author summary: In this study, we describe a novel tussle between the pathogenic bacterium Chlamydia trachomatis and its infected host cell. This interaction is centered on the primary cilium, which is a protrusion on the cell surface that is important for many cellular functions. While the primary cilium is present on cells infected by Chlamydia during a natural infection, it is absent from dividing cells used to study Chlamydia infections in cell culture. We found that Chlamydia infection caused loss of the primary cilium by activating the cellular cilia disassembly machinery and induced a quiescent host cell to re-enter the cell cycle. Furthermore, we showed that the presence of a primary cilium severely inhibited the production of infectious chlamydial progeny. Thus, the host cell uses the primary cilium to restrict a productive infection, while Chlamydia induces cilia disassembly as a countermeasure. This host-pathogen interaction could be unique to Chlamydia, but it could also have been missed for other intracellular bacteria and viruses, which are commonly studied in cells that lack a primary cilium. This work could lead to new antimicrobial approaches targeting the primary cilium. [ABSTRACT FROM AUTHOR]

Pregnancy is an important process in women’s life, which is widely concerned by women. In recent years, the incidence of premature delivery (PTD) becomes more and more higher due to the development of auxiliary reproduction and ovulation induction technologies and the changes of pregnant women’s lifestyle and physical quality. PTD not only affects postpartum recovery and causes great physical pains, but it also has adverse effects on the birth state of neonates and even leads to neonatal death The predictive values of cervix length (CL) measurement based on transvaginal ultrasonography (TVUS) and pathological examination of placenta for premature delivery (PTD) were investigated and the correlation between PTD and infection was analyzed. 120 pregnant women with PTD or high-risk factors for PTD admitted to The Affiliated Hospital of Southwest Medical University between February 2020 and March 2022 were included as the subjects and underwent pathological examination of placenta and TVUS for CL measurement. The final gestational age was set as the standard for the evaluation on the predictive values of pathological examination of placenta and TVUS. What’s more, 36 subjects in PTD group and 84 in normal delivery group (control group) underwent pathological examination of placenta for the analysis of the correlation between PTD and infection. The joint inspection method showed significantly better sensitivity, specificity, PPV, and NPV compared to single CL or pathological examination of the placenta (P< 0.05). Among pregnant women, those with CL ⩽ 30 mm and positive placental pathology had a higher proportion compared to those with CL > 30 mm and negative placental pathology (P< 0.05). Furthermore, the incidence of Ureaplasma Urealyticum (UU), Chlamydia Trachomatis (CT), and Chorioamnionitis (CA) in vaginal discharge of the preterm delivery (PTD) group was significantly higher than that of the control group (P< 0.05). The combination of CL ⩽ 30 mm and positive placental pathology could effectively predict PTD and placental infection was notably correlated with the occurrence of PTD. [ABSTRACT FROM AUTHOR]

Introduction: We assessed the in vitro anti-chlamydial activity of fresh vaginal secretions, deciphering the microbial and metabolic components able to counteract Chlamydia trachomatis viability. Methods: Forty vaginal samples were collected from a group of reproductiveaged women and their anti-chlamydial activity was evaluated by inhibition experiments. Each sample underwent 16S rRNA metabarcoding sequencing to determine the bacterial composition, as well as ¹H-NMR spectroscopy to detect and quantify the presence of vaginal metabolites. Results: Samples characterized by a high anti-chlamydial activity were enriched in Lactobacillus, especially Lactobacillus crispatus and Lactobacillus iners, while notactive samples exhibited a significant reduction of lactobacilli, along with higher relative abundances of Streptococcus and Olegusella. Lactobacillus gasseri showed an opposite behavior compared to L. crispatus, being more prevalent in not-active vaginal samples. Higher concentrations of several amino acids (i.e., isoleucine, leucine, and aspartate; positively correlated to the abundance of L. crispatus and L. jensenii) lactate, and 4-aminobutyrate were the most significant metabolic fingerprints of highly active samples. Acetate and formate concentrations, on the other hand, were related to the abundances of a group of anaerobic opportunistic bacteria (including Prevotella, Dialister, Olegusella, Peptostreptococcus, Peptoniphilus, Finegoldia and Anaerococcus). Finally, glucose, correlated to Streptococcus, Lachnospira and Alloscardovia genera, emerged as a key molecule of the vaginal environment: indeed, the antichlamydial effect of vaginal fluids decreased as glucose concentrations increased. Discussion: These findings could pave the way for novel strategies in the prevention and treatment of chlamydial urogenital infections, such as lactobacilli probiotic formulations or lactobacilli-derived postbiotics. [ABSTRACT FROM AUTHOR]

Background The pathogenesis of Chlamydia trachomatis is associated with the induction of the host inflammatory response; however, the precise underlying molecular mechanisms remain poorly understood. Methods CT622, a T3SS effector protein, has an important role in the pathogenesis of C trachomatis ; however, whether CT622 can induce a host inflammatory response is not understood. Our findings demonstrate that CT622 induces the expression of interleukins 6 and 8 (IL-6 and IL-8). Mechanistically, these effects involve the activation of the MAPK/NF-κB signaling pathways (mitogen-activated protein kinase/nuclear factor κB). Results Interestingly, we demonstrated that the suppression of toll-like receptor 4 using small interfering RNA markedly reduced the phosphorylation of ERK, p38, JNK, and IκBα, concomitant with a significant decrease in IL-6 and IL-8 secretion. Conversely, disruption of toll-like receptor 2 abrogated the CT622-induced upregulation of IL-8 and activation of ERK, whereas IL-6 expression and p38, JNK, and IκBα phosphorylation were unaffected. Conclusions Taken together, these results indicate that CT622 contributes to the inflammatory response through the toll-like receptor 2/4–mediated MAPK/NF-κB pathways, which provides insight into the molecular pathology of C trachomatis infection. [ABSTRACT FROM AUTHOR]

Objectives: Chlamydia trachomatis (chlamydia) is one of the most reported bacterial sexually transmitted infections (STI) worldwide. Chlamydia can cause long term complications such as pelvic inflammatory disease (PID), ectopic pregnancy (EP) and tubal factor infertility (TFI). Changing testing strategies, for example reduced asymptomatic testing, influence chlamydia surveillance, highlighting the need for exploring alternative ways of monitoring chlamydia. We investigated the possibility of introducing routine surveillance of chlamydia related long term complications. Methods: A qualitative study including 15 in-depth interviews with a purposive sample of gynaecologists, general practitioners (GP), sexual health and emergency doctors was conducted in the Netherlands in 2021–2022. A semi-structured interview guide focused on experiences with diagnosis and registration of PID, EP and TFI and how a change in asymptomatic chlamydia testing strategy might influence this. Interviews were transcribed and analysed using a thematic approach. Results: Analysis showed that gynaecologists most frequently reported diagnosing PID, EP and TFI. Other professions rarely diagnose these complications, with emergency doctors only diagnosing EP. Most respondents reported unique registration codes for PID and EP, but the coding for TFI is more ambiguous. They reflected that diagnosis and registration of PID, EP and TFI are handled differently within their professions. Most respondents acknowledged registration in diagnostic codes as a useful surveillance tool. They expressed concerns in representativeness (e.g. differences in interpretation of diagnosis criteria) and data quality for surveillance. Conclusions: Patient files of gynaecologists are likely to be most complete for monitoring trends of diagnosed chlamydia related long term complications in the Netherlands. However, when establishing a chlamydia complication surveillance system, professionals should be engaged in further standardizing diagnosis and registration practices. This will improve the quality and interpretability of complication surveillance and facilitate comparison between countries. [ABSTRACT FROM AUTHOR]

The polymorphic membrane proteins (Pmps) are a family of autotransporters that play an important role in infection, adhesion and immunity in Chlamydia trachomatis. Here we show that the characteristic GGA(I,L,V) and FxxN tetrapeptide repeats fit into a larger repeat sequence, which correspond to the coils of a large beta-helical domain in high quality structure predictions. Analysis of the protein using structure prediction algorithms provided novel insight to the chlamydial Pmp family of proteins. While the tetrapeptide motifs themselves are predicted to play a structural role in folding and close stacking of the beta-helical backbone of the passenger domain, we found many of the interesting features of Pmps are localized to the side loops jutting out from the beta helix including protease cleavage, host cell adhesion, and B-cell epitopes; while T-cell epitopes are predominantly found in the beta-helix itself. This analysis more accurately defines the Pmp family of Chlamydia and may better inform rational vaccine design and functional studies. [ABSTRACT FROM AUTHOR]

Chlamydia invasion of epithelial cells is a pathogen-driven process involving two functionally distinct effectors – TarP and TmeA. They collaborate to promote robust actin dynamics at sites of entry. Here, we extend studies on the molecular mechanism of invasion by implicating the host GTPase dynamin 2 (Dyn2) in the completion of pathogen uptake. Importantly, Dyn2 function is modulated by TarP and TmeA at the levels of recruitment and activation through oligomerization, respectively. TarP-dependent recruitment requires phosphatidylinositol 3-kinase and the small GTPase Rac1, while TmeA has a post-recruitment role related to Dyn2 oligomerization. This is based on the rescue of invasion duration and efficiency in the absence of TmeA by the Dyn2 oligomer-stabilizing small molecule activator Ryngo 1-23. Notably, Dyn2 also regulated turnover of TarP- and TmeA-associated actin networks, with disrupted Dyn2 function resulting in aberrant turnover dynamics, thus establishing the interdependent functional relationship between Dyn2 and the effectors TarP and TmeA. Chlamydia trachomatis invades host epithelial cells using the two effectors TarP and TmeA. Here, Romero et al find that host GTPase dynamin 2 is also recruited to invasion sites where it is required for uptake, and is regulated by TarP and TmeA. [ABSTRACT FROM AUTHOR]

Background: Trachoma causes blindness due to repeated conjunctival infection by Chlamydia trachomatis (Ct). Transmission intensity is estimated, for programmatic decision-making, by prevalence of the clinical sign trachomatous inflammation—follicular (TF) in children aged 1–9 years. Research into complementary indicators to field-graded TF includes work on conjunctival photography, tests for ocular Ct infection, and serology. The perceived acceptability and feasibility of these indicators among a variety of stakeholders is unknown. Methodology: Focus group discussions (FGDs) with community members and in-depth interviews (IDIs) with public health practitioners in Tanzania were conducted. FGDs explored themes including participants' experience with, and thoughts about, different diagnostic approaches. The framework method for content analysis was used. IDIs yielded lists of perceived strengths of, and barriers to, implementation for programmatic use of each indicator. These were used to form an online quantitative survey on complementary indicators distributed to global stakeholders via meetings, mailing lists, and social media posts. Results: Sixteen FGDs and 11 IDIs were conducted in October–November 2022. In general, all proposed sample methods were deemed acceptable by community members. Common themes included not wanting undue discomfort and a preference for tests perceived as accurate. Health workers noted the importance of community education for some sample types. The online survey was conducted in April–May 2023 with 98 starting the questionnaire and 81 completing it. Regarding barriers to implementing diagnostics, the highest agreement items related to feasibility, rather than acceptability. No evidence of significant differences was found in responses pertaining to community acceptability based on participant characteristics. Conclusions: All of the indicators included were generally deemed acceptable by all stakeholders in Tanzania, although community education around the benefits and risks of different sample types, as well as addressing issues around feasibility, will be key to successful, sustainable integration of these indicators into trachoma programs. Author summary: Trachoma is a disease that causes blindness through conjunctival infection with the bacterium Chlamydia trachomatis. Trachoma is targeted for global elimination by 2030. To know whether population-level interventions are required, we must know how intensely conjunctival C. trachomatis is being transmitted in a population. The current proxy recommended by the World Health Organization is prevalence of a clinical sign of active (inflammatory) trachoma: trachomatous inflammation—follicular. However, this indicator has several drawbacks. Policy-makers are considering the utility of a number of complementary indicators, including conjunctival photography and tests for infection and serology. We sought the opinions of different stakeholders to determine the acceptability and feasibility of complementary indicators for use in trachoma programs. In Tanzania, we undertook focus group discussions with community members and in-depth interviews with public health practitioners. We also conducted an online survey of global stakeholders. We found that all the proposed test types were acceptable to stakeholders in Tanzania; common themes included not wanting undue discomfort and a preference for test types perceived to be accurate. Community education and building trust was deemed critical. From the online survey, the most agreed-upon barriers to implementation of each method were related to concerns about feasibility, rather than acceptability. [ABSTRACT FROM AUTHOR]

The obligate intracellular bacterium, Chlamydia trachomatis, has evolved to depend on its human host for many metabolites, including most amino acids and three of the four nucleotides. Given this, it is not surprising that depletion of a single amino acid in the host cell growth medium blocks chlamydial replication. Paradoxically, supra-normal levels of some amino acids also block productive replication of Chlamydia. Here, we have determined how elevated serine levels, generated by exogenous supplementation, impede chlamydial inclusion development and reduce the generation of infectious progeny. Our findings reveal that human serine racemase, which is broadly expressed in multiple tissues, potentiates the anti-chlamydial effect of elevated serine concentrations. In addition to reversibly converting l-serine to d-serine, serine racemase also deaminates serine via β-elimination. We have determined that d-serine does not directly impact Chlamydia; rather, ammonia generated by serine deamination limits the productive chlamydial replication. Our findings imply that ammonia produced within host cells can traverse the chlamydial inclusion membrane. Further, this property of serine deaminase can be exploited to sensitize Chlamydia to concentrations of doxycycline that are otherwise not bactericidal. Because exogenously elevated levels of serine can be tolerated over extended periods, the broad expression pattern of serine racemase indicates it to be a host enzyme whose activity can be directed against multiple intracellular bacterial pathogens. From a therapeutic perspective, demonstrating host metabolism can be skewed to generate an anti-bacterial metabolite that synergizes with antibiotics, we believe our results provide a new approach to target intracellular pathogens. [ABSTRACT FROM AUTHOR]

Objective of the study: to explore the impact of medical abortion on infections, stress, and the vaginal microbiota, providing essential insights into the associated risks and the need for comprehensive care. Materials and methods. A total of 120 patients were examined, divided into groups: 50 women who underwent medical abortion, 50 women underwent surgical abortion and 20 women with no abortions as the control group. Additionally, the women were categorized based on stress levels into high stress group (29 women), medium stress group (54 women), and low stress group (17 women). Bacteriological studies were conducted to assess the species composition and quantitative composition of the vaginal microbiota in women post-abortion and with varying levels of stress. Results. The study found significant alterations in the vaginal microbiota of women post-abortion, differentiated by the type of abortion and stress levels. Women who underwent medical abortions exhibited higher levels of S. epidermidis, including strains with hemolytic properties, compared to those who had surgical abortions. The concentration of S. epidermidis in the medical abortion group was significantly higher than in healthy women, suggesting a potential link between medical abortion and increased susceptibility to opportunistic infections. Additionally, higher concentrations of E. coli, particularly hemolytic strains, were found in both abortion groups, with a slightly higher prevalence in the medical abortion group, highlighting an increased risk of post-abortion infections. The level of stress significantly affects the composition of the vaginal microbiota. Women experiencing high stress post-abortion showed a more pronounced dysbiosis compared to those with moderate or low stress levels. High-stress individuals had significantly elevated levels of pathogenic microorganisms, including S. aureus, S. agalactiae, and various Enterobacteriaceae, and a marked deficiency in protective Lactobacillus spp. The study also identified a higher incidence of mixed infections in high-stress women, often involving bacterial and viral pathogens such as G. vaginalis, C. trachomatis, U. urealyticum, and herpes simplex virus. Comparative analysis revealed that both types of abortion are associated with microbiota disruptions; however, medical abortions had a more substantial impact on certain pathogenic bacteria. For instance, the levels of Candida spp. were significantly higher in the medical abortion group compared to the surgical group, indicating a higher risk of fungal infections. Conversely, the concentration of Lactobacillus spp. was notably lower in women who underwent surgical abortions, suggesting a more severe impact on beneficial microbiota from surgical procedures. Conclusions. The findings underscore the importance of monitoring and managing the vaginal microbiota in women post-abortion, particularly those undergoing medical abortions and those experiencing high stress levels. Prophylactic and therapeutic measures, including the use of probiotics, should be considered to mitigate the risk of infections and restore the balance of protective bacteria. [ABSTRACT FROM AUTHOR]

Chlamydia (C.) trachomatis, a leading cause of sexually transmitted infections (STIs) worldwide, continues to be a significant public health concern. The majority of infections are asymptomatic and, when left untreated, severe sequelae such as infertility and chronic pelvic pain can occur. Despite decades of research, an effective vaccine remains elusive. This review focuses on the potential of Major Outer Membrane Protein (MOMP)-derived constructs as promising candidates for C. trachomatis vaccination. MOMP, the most abundant protein in the outer membrane of C. trachomatis, has been a focal point of vaccine research over the years due to its antigenic properties. To overcome issues associated with the use of full MOMP as a vaccine antigen, derivative constructs have been studied. As these constructs are often not sufficiently immunogenic, antigen delivery systems or accompanying adjuvants are required. Additionally, several immunization routes have been explored with these MOMP-derived vaccine antigens, and determining the optimal route remains an ongoing area of research. Future directions and challenges in the field of C. trachomatis vaccination are discussed. [ABSTRACT FROM AUTHOR]

Some infectious agents have the potential to cause specific modifications in the cellular microenvironment that could be propitious to the carcinogenesis process. Currently, there are specific viruses and bacteria, such as human papillomavirus (HPV) and Helicobacter pylori, that are well established as risk factors for neoplasia. Chlamydia trachomatis (CT) infections are one of the most common bacterial sexually transmitted infections worldwide, and recent European data confirmed a continuous rise across Europe. The infection is often asymptomatic in both sexes, requiring a screening program for early detection. Notwithstanding, not all countries in Europe have it. Chlamydia trachomatis can cause chronic and persistent infections, resulting in inflammation, and there are plausible biological mechanisms that link the genital infection with tumorigenesis. Herein, we aimed to understand the epidemiological and biological plausibility of CT genital infections causing endometrial, ovarian, and cervical tumors. Also, we covered some of the best suitable in vitro techniques that could be used to study this potential association. In addition, we defend the point of view of a personalized medicine strategy to treat those patients through the discovery of some biomarkers that could allow it. This review supports the need for the development of further fundamental studies in this area, in order to investigate and establish the role of chlamydial genital infections in oncogenesis. [ABSTRACT FROM AUTHOR]

Objective To assess the prevalence of mycoplasma genitalium (MG) in patients attending sexually transmitted disease (STD) clinic in Guangzhou, and to provide an epidemiological foundation for clinical treatment and laboratory diagnostics. Methods Utilizing real-time polymerase chain reaction (PCR), we analyzed MG DNA in 2, 749 clinical specimens collected from 2, 722 outpatients in the Dermatology Hospital of Southern Medical University from July 2019 to December 2021. Concurrent testing for MG, Chlamydia trachomatis(CT), and Neisseria gonorrhoeae (NG) was performed on 2, 382 of these specimens. Patient data extracted from medical records were used to investigate the correlation between STD symptoms and MG infection. Results The investigation revealed that the overall prevalence of MG infection was 4.4 % among the sampled patients (120 out of 2,722), with a higher prevalence in males (4.9 %, or 87 out of 1, 790) compared to in females (3.5 %, or 33 out of 932). Notably, the prevalence decreased with increasing age. The highest incidence of MG infection was observed in females aged 18 ~ 25 years (6.4 %, or 18 out of 281), while the lowest was in males aged 46 years and above (1.5%, or 5 out of 342), showing a statistically significant variation across age groups (P < 0.05). Among males with urethritis symptoms, MG positive rate was significantly higher at 7.3 % (42 out of 574). The rate of single MG infection was prominent, accounting for 89.9 % (71 out of 79) in MG-positive male patients and 61.5 % (16 out of 26) in MG-positive female patients. Co-infection rate of MG with CT was 1.2 % in females and 0.3 % in males, indicating a significant difference (P < 0.05). Conclusion The findings suggest a relatively high prevalence of MG infection and co-infection with CT among STD clinic attendees in Guangzhou, particularly in the younger demographic. The study underscores the need for early screening and vigilant surveillance of MG to mitigate its transmission among sexually active populations at high risk. [ABSTRACT FROM AUTHOR]

Introduction: The rates of gonorrhea and chlamydia have been increasing in the years preceding the COVID19 pandemic. Because most gonorrhea and chlamydia infections are located in the oropharynx and rectum for men who have sex with men (MSM), and because at-home self-collected swabs for these infections are not licensed by Health Canada or the United States Food and Drug Administration, decreased accessed to in-person care during and since the COVID19 pandemic potentially means missed case findings. Objectives: To evaluate the performance of at-home self-collected pharyngeal and rectal swabs for gonorrhea and chlamydia nucleic acid amplification testing. Methodology: All persons who contacted our Sexual Health Clinic and who had a clinical indication to complete oral and/or rectal swabs for gonorrhea and chlamydia were invited to complete at-home swabs in advance of their scheduled appointments. We mailed swabs and instructions to those who consented. Participants brought these swabs to their scheduled in clinic appointments, where we repeated the same swabs. All matching swabs were sent to the laboratory for analysis to determine concordance. Results: From September 8, 2022 to July 18, 2023, we enrolled 296 eligible participants who provided 1184 swabs. For analysis, cancelled specimens and specimens with invalid results were excluded, leaving 1032 swabs for comparison. We identified 66 STI diagnoses in 47 unique participants. Overall accuracy was high (exceeding 99%), except for rectal chlamydia, which was 96.0%. While the performance of self-swabs for chlamydia was lower compared to gonorrhea, at-home swabs identified six chlamydia infections that were missed by in-clinic collected swabs (two pharyngeal, four rectal). Removing these six cases as "false positives" increased overall accuracy for chlamydia detection to 99.7% (pharyngeal) and 97.8% (rectal). Conclusion: Self-collected at-home swabs had good performance acceptable for gonorrhea and chlamydia nucleic acid amplification testing. [ABSTRACT FROM AUTHOR]

Background: Tubal factor infertility (TFI) is common in sub-Saharan Africa and often secondary to pelvic inflammatory disease (PID). Anaerobes associated with bacterial vaginosis (BV) are also found in PIDs widely dominated by Chlamydia trachomatis (C. trachomatis), whose role in TFI is better demonstrated than that of BV. Objectives: To determine the prevalence of BV and C. trachomatis and to investigate the association between BV, C. trachomatis and TFI. Methods: We included 137 patients treated for infertility between January 2020 and November 2021. Cases were defined as women with infertility aged 18-45 years presenting with TFI (n = 52), and controls as infertile women in the same age groups without TFI (n = 85). Data on social habits, life style and infertility parameters were collected, and we performed screening for BV and C. trachomatis. Multiple regression was used to measure associations. Results: The prevalence of BV and C. trachomatis was 42.3% (58/137) and 23.4% (32/137), respectively. BV (61.5% vs 30.6%, p<0.001) and C. trachomatis (48.1 vs 8.2%, p<0.001) were more frequent in cases of TFI. BV and C. trachomatis increased the risk of TFI approximately 4-fold [aOR: 3.77 (1.61-8.83), p=0.002] and 14-fold [aOR: 13.77 (4.59-41.27), p<0.001], respectively. Conclusion: BV and C. trachomatis infection are strongly associated with TFI in Bukavu. Prevention and screening should be implemented to reduce the risk of TFI. [ABSTRACT FROM AUTHOR]

Chlamydia trachomatis is the predominant bacterium transmitted through sexual activity, usually leading to symptomless infection and complications like infertility. Therefore, it is crucial to have an efficient diagnostic technique to minimize the long-term consequences of the disease. A case-control study in which 4 ml blood samples and endocervical swabs were collected from 134 infertile and 50 fertile Kurdish women. DNA was extracted from endocervical swabs using PCR to detect C. trachomatis. Also, the serological test was performed using the enzymelinked immunosorbent assay (ELISA) test to estimate anti-chlamydial IgM from serum. Among the study participants, we found that from 134 infertile participants, Women with secondary infertility showed a higher prevalence, 86 (64.1%), than primary infertility, 48 (35.8%). The overall prevalence of genital C. trachomatis, determined through PCR testing, was found to be 62 cases (46.2%) among infertile women. Among these cases, 21 individuals (33.8%) were diagnosed with primary infertility, while 41 individuals (66.1%) had secondary infertility. In contrast, there were no positives among the fertile group. All fertile and infertile female groups were positive for anti-chlamydial IgM antibody by using ELISA. Still, the intensity of response differed between cases, with the highest rate observed in unexplained infertility (UI) (71.42%), followed by endometriosis (Endo) (66.66%), tubal factor infertility (TFI) (50%), and polycystic ovarian syndrome (PCOS) (37.5%). These results highlight the importance of considering C. trachomatis as a potential factor in infertility cases. The results concluded the highest frequency of chlamydial infection was among women with infertility than fertile women. PCR is the most reliable and exact diagnostic method for detecting it. [ABSTRACT FROM AUTHOR]

Background: Bacterial vaginosis is a common vaginal syndrome among females, which leads to significant morbidity and complications, if left untreated. The association of bacterial vaginosis with various sexually transmitted infections has been mentioned in previous literature. However, studies on the intermediate Nugent Score are lacking. This study was planned to examine the association of sexually transmitted infections with the intermediate Nugent Score. Materials and Methods: The study included was conducted to include females presenting with vaginal discharge, burning micturition, itching, lower abdominal pain and infertility. The Nugent scoring was used to categorize patients into those having normal flora, intermediate or bacterial vaginosis. Conventional and molecular techniques targeting Trichomonas vaginalis, Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis, Syphilis, Neisseria gonorrhoeae and vulvovaginal candidiasis were performed. Results: A total of 3,531 clinical samples were collected from females with a median age of 28.0 years. The number of patients with bacterial vaginosis and intermediate Nugent Score and positive cases were significantly higher in the 21–35 years age group (P < 0.0001). We observed that the likelihood of test results being positive for Trichomonas vaginalis was higher (P < 0.05), as the abnormality of the vaginal flora increased. Mycoplasma hominis was observed to be significantly higher in the intermediate Nugent Score group than the BV-positive patients (0.6 vs 0.2, P = 0.002). The number of vulvovaginal candidiasis cases in both the bacterial vaginosis-negative and bacterial vaginosis-positive groups were nearly the same (9.3 vs 9.8%). Limitations: Individual follow-up couldn’t be performed on the patients. Conclusions: We observed that the dysbiosis in vaginal microbiota, with an increase in Nugent scoring, was significantly associated with an increased risk for the acquisition of sexually transmitted infections and vulvovaginal candidiasis. [ABSTRACT FROM AUTHOR]

Trachoma is the world-leading infectious cause of preventable blindness and is caused by the bacteria Chlamydia trachomatis. In developing countries, diagnosis is usually based on clinical evaluation. Serological-based tests are cheaper than molecular-based ones, but the latter are more sensitive and specific. The present study developed a new duplex qPCR which concomitantly detects the C. trachomatis cryptic plasmid and the human 18S rRNA gene, with an LOD95% for C. trachomatis DNA of 13.04 genome equivalents per reaction. The new qPCR was tested using 50 samples from an endemic area and 12 from a non-endemic area that were previously characterized using direct immunofluorescence assay (DFA) and clinical evaluation. Among the 50 endemic samples, 3 were found to be positive by clinical evaluation (6%), 18 were found to be positive by DFA (36%), and 48 were found to be positive by qPCR (96%). Next, the new duplex qPCR was validated using 50 samples previously characterized by qPCR. Validation was carried out on a benchtop instrument (ABI7500) or on a portable point-of-care instrument (Q3-Plus), showing 95% specificity and 100% sensitivity. The ubiquitous presence of C. trachomatis DNA in samples from the endemic region confirms that constant monitoring is of paramount importance for the effective measurement of the elimination of trachoma. The newly developed duplex qPCR presented in this study, along with its validation in a portable qPCR system, constitutes important tools toward achieving this goal. [ABSTRACT FROM AUTHOR]

Chlamydia trachomatis infection is the leading cause of bacterial urogenital infection and has been demonstrated to drive inflammation and scarring of the reproductive tract. Recent studies have identified key triggers of proinflammatory adaptive immune responses driven by innate leukocytes and epithelia driving immunopathology. Utilizing chimeric mouse models, we investigated the definitive source and role of IL17 and IL17 signalling receptors during early Chlamydia muridarum infection of the female urogenital tract. Bone marrow transplants from wild‐type (WT) and IL17A−/− mice to recipients demonstrated equivocal infection kinetics in the reproductive tract, but interestingly, adoptive transfer of IL17A−/− immune cells to WT recipients resulted in no infertility, suggesting a haematopoietic (as opposed to tissue) source of IL17 driving immunopathology. To further delineate the role of IL17 in immunopathology, we infected WT and IL17 receptor A (IL17RA)−/− female mice and observed a significant reduction in immunopathology in IL17RA−/− mice. WT bone marrow transplants to IL17RA−/− recipient mice prevented hydrosalpinx, suggesting signalling through IL17RA drives immunopathology. Furthermore, early chemical inhibition of IL17 signalling significantly reduced hydrosalpinx, suggesting IL17 acts as an innate driver of disease. Early during the infection, IL17 was produced by γδ T cells in the cervico‐vagina, but more importantly, by neutrophils at the site of infertility in the oviducts. Taken together, these data suggest innate production of IL17 by haematopoietic leukocytes drives immunopathology in the epithelia during early C. muridarum infection of the female reproductive tract. [ABSTRACT FROM AUTHOR]

Introduction: Vitamin D deficiency is the most common nutritional deficiency worldwide. Chronic vitamin D deficiency causes immune system dysfunction, which increases susceptibility to pathogens such as bacteria, especially intracellular parasites, and viruses. Chlamydia trachomatis (C. t) is an obligate intracellular parasitic bacterium that causes a variety of sequelae. We speculated that vitamin D might be associated with C. t infection. This study aimed to address this gap in knowledge by investigating the relationship between vitamin D and C. t infection using both in vitro and in vivo models. Methods and results: The addition of calcitriol to McCoy cell culture in vitro delayed and reduced the quantity and volume of inclusions compared to the control group. Macrophages of peritoneally lavaged mice co-cultured with McCoy decreased the infection rate and delayed the appearance of inclusions. In mice models of vitamin D deficiency, mice in the VD-group exhibited more severe genital tract inflammation and a longer duration of infection after inoculation with C. t in the genital tract. Supplementing these mice with vitamin D3 during treatment enhanced the therapeutic effect of antibiotics. We also conducted a case-control study involving 174 C. t-positive patients (95 males and 79 females) and 380 healthy volunteers (211 males and 169 females) aged 20-49 from January 2016 to March 15, 2017. Serum 25-(OH)D concentration was measured by assessing morning fasting blood samples of healthy volunteers and C. t-positive patients 1 day before antibiotic treatment and the next day after one course of treatment. The patients were followed up for 1 month and evaluated for recovery. The results showed that vitamin D deficiency was a risk factor for C. t infection and treatment failure. Conclusion: In summary, findings from experimental and clinical studies indicate a close association between vitamin D levels and C. t infection and treatment outcomes. Given the affordability and safety of vitamin D, both healthy individuals and patients should focus on vitamin D intake. Vitamin D supplementation could enhance treatment success and should be used as an adjunctive therapy alongside antibiotic therapy for C. t infections, pending confirmation in larger, prospective, randomized controlled trials. [ABSTRACT FROM AUTHOR]

Sexually transmitted diseases (STDs) are a global concern because approximately 1 million new cases emerge daily. Most STDs are curable, but if left untreated, they can cause severe long-term health implications, including infertility and even death. Therefore, a test enabling rapid and accurate screening and genotyping of STD pathogens is highly awaited. Herein, we present the development of the DNA-based 6STD Genotyping 9G Membrane test, a lateral flow strip membrane assay, for the detection and genotyping of six STD pathogens, including Trichomonas vaginalis, Ureaplasma urealyticum, Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis, and Mycoplasma genitalium. Here, we developed a multiplex PCR primer set that allows PCR amplification of genomic materials for these six STD pathogens. We also developed the six ssDNA probes that allow highly efficient detection of the six STD pathogens. The 6STD Genotyping 9G Membrane test lets us obtain the final detection and genotyping results in less than 30 m after PCR at 25 °C. The accuracy of the 6STD Genotyping 9G membrane test in STD genotyping was confirmed by its 100% concordance with the sequencing results of 120 clinical samples. Therefore, the 6STD Genotyping 9G Membrane test emerges as a promising diagnostic tool for precise STD genotyping, facilitating informed decision-making in clinical practice. [ABSTRACT FROM AUTHOR]

This article discusses the importance of addressing Chlamydia trachomatis (Ct) infection and its transmission through sexual routes. The authors emphasize the need for targeted and prolonged antibiotic therapy to interfere with the life cycle of Ct and reduce antibiotic resistance. They also highlight the role of reducing indiscriminate pesticide pollution, which can interfere with the food chain and biodiversity. Additionally, the authors discuss the active role of dipterans (flies) in the transmission of Ct in urban areas and the importance of raising awareness about sexually transmitted infections among health authorities. The article suggests that improving sex education and promoting intimate hygiene can help prevent the spread of Ct. [Extracted from the article]

Background and Objectives: Chlamydia trachomatis (C. trachomatis) represents one of the most prevalent bacterial sexually transmitted diseases. This study aims to explore the relationship between HLA alleles/genotypes/haplotypes and C. trachomatis infection to better understand high-risk individuals and potential complications. Materials and Methods: This prospective study recruited participants from Transylvania, Romania. Patients with positive NAAT tests for C. trachomatis from cervical/urethral secretion or urine were compared with controls regarding HLA-DR and -DQ alleles. DNA extraction for HLA typing was performed using venous blood samples. Results: Our analysis revealed that the presence of the DRB1*13 allele significantly heightened the likelihood of C. trachomatis infection (p = 0.017). Additionally, we observed that individuals carrying the DRB1*01/DRB1*13 and DQB1*03/DQB1*06 genotype had increased odds of C. trachomatis infection. Upon adjustment, the association between the DRB1*01/DRB1*13 genotype and C. trachomatis remained statistically significant. Conclusions: Our findings underscore the importance of specific HLA alleles and genotypes in influencing susceptibility to C. trachomatis infection. These results highlight the intricate relationship between host genetics and disease susceptibility, offering valuable insights for targeted prevention efforts and personalized healthcare strategies. [ABSTRACT FROM AUTHOR]

Trachoma is the leading infectious cause of blindness worldwide and is now largely confined to around 40 low- and middle-income countries. It is caused by Chlamydia trachomatis (Ct), a contagious intracellular bacterium. The World Health Organization recommends mass drug administration (MDA) with azithromycin for treatment and control of ocular Ct infections, alongside improving facial cleanliness and environmental conditions to reduce transmission. To understand the molecular epidemiology of trachoma, especially in the context of MDA and transmission dynamics, the identification of Ct genotypes could be useful. While many studies have used the Ct major outer membrane protein gene (ompA) for genotyping, it has limitations. Our study applies a typing system novel to trachoma, Multiple Loci Variable Number Tandem Repeat Analysis combined with ompA (MLVA-ompA). Ocular swabs were collected post-MDA from four trachoma-endemic zones in Ethiopia between 2011–2017. DNA from 300 children with high Ct polymerase chain reaction (PCR) loads was typed using MLVA-ompA, utilizing 3 variable number tandem repeat (VNTR) loci within the Ct genome. Results show that MLVA-ompA exhibited high discriminatory power (0.981) surpassing the recommended threshold for epidemiological studies. We identified 87 MLVA-ompA variants across 26 districts. No significant associations were found between variants and clinical signs or chlamydial load. Notably, overall Ct diversity significantly decreased after additional MDA rounds, with a higher proportion of serovar A post-MDA. Despite challenges in sequencing one VNTR locus (CT1299), MLVA-ompA demonstrated cost-effectiveness and efficiency relative to whole genome sequencing, providing valuable information for trachoma control programs on local epidemiology. The findings suggest the potential of MLVA-ompA as a reliable tool for typing ocular Ct and understanding transmission dynamics, aiding in the development of targeted interventions for trachoma control. Author summary: Trachoma is the leading infectious cause of blindness worldwide and is largely confined to low- and middle-income countries. It is caused by Chlamydia trachomatis (Ct), a contagious intracellular bacterium. The World Health Organization recommends mass drug administration (MDA) with the antibiotic azithromycin for treatment of ocular Ct infections, alongside improving facial cleanliness and environmental conditions to reduce transmission. In most regions MDA is successfully reducing trachoma prevalence to the point where it is no longer a public health issue, however in some areas trachoma persists despite multiple years of interventions. To investigate why trachoma persists, especially in the context of MDA and transmission dynamics, the identification of Ct sequence types may aid in understanding and gauge progress of trachoma control. Our study applies a Ct typing system new to trachoma, which augments the standard method by adding three loci with high mutation rates. Results show that the typing system was able to discriminate between variants with greater resolution than the standard method, and was both cost-effective and more efficient relative to the gold-standard of whole genome sequencing. The findings suggest that this novel method is a reliable tool for typing ocular Ct, which can aid in the development of targeted interventions for trachoma control through improved understanding of Ct transmission. [ABSTRACT FROM AUTHOR]

An issue with many current vaccines is the dependency on broadly inflammatory adjuvants, such as aluminum hydroxide or aluminum salts that affect many immune- and non-immune cells. These adjuvants are not necessarily activating all antigen-presenting cells (APCs) that take up the antigen and most likely they also activate APCs with no antigen uptake, as well as many non-immune cells. Conjugation of antigen and adjuvant would enable the use of smaller amounts of adjuvant and avoid unnecessary tissue damage and activation of bystander cells. It would ensure that all APCs that take up the antigen would also become activated and avoid that immature and non-activated APCs present the antigen to T cells without a co-stimulatory signal, leading to tolerogenesis. We have developed a novel vaccine that co-deliver antigen and a nucleotide adjuvant to the same APC and lead to a strong activation response in dendritic cells and macrophages. The vaccine is constructed as a fusion-protein with an antigen fused to the DNA/RNA-binding domain from the Hc2 protein from Chlamydia trachomatis. We have found that the fusion protein is able to package polyinosinic:polycytidylic acid (poly(I:C)) or dsDNA into small particles. These particles were taken up by macrophages and dendritic cells and led to strong activation and maturation of these cells. Immunization of mice with the fusion protein packaged poly(I:C) led to a stronger antibody response compared to immunization with a combination of poly(I:C) and antigen without the Hc2 DNA/RNA-binding domain. [ABSTRACT FROM AUTHOR]

Background: Genital infection with Chlamydia trachomatis (C. trachomatis) is a major public health issue worldwide. It can lead to cervicitis, urethritis, and infertility. This study was conducted to determine the characteristics of genital C. trachomatis infection among women attending to the infertility and gynecology clinics. Methods: Endocervical swabs were collected from 8,221 women for C. trachomatis nucleotide screening and genotyping, while serum samples were collected for C. trachomatis pgp3 antibody determination using luciferase immunosorbent assays. Results: High C. trachomatis DNA prevalence (3.76%) and seroprevalence (47.46%) rates were found, with genotype E (27.5%) being the most prevalent. C. trachomatis omp1 sense mutation was associated with cervical intraepithelial neoplasia (CIN) (odds ratio [OR] = 6.033, 95% confidence interval [CI] = 1.219–39.185, p = 0.045). No significant differences in C. trachomatis seroprevalence rates were observed between women with detectable C. trachomatis DNA in the infertility and routine physical examination groups (86.67% vs. 95%, p > 0.05); however, among women with negative C. trachomatis DNA, the former group had a markedly higher seroprevalence than the latter group (56.74% vs. 20.17%, p < 0.001). C. trachomatis DNA, but not pgp3 antibody, was significantly associated with CIN (OR = 4.087, 95% CI = 2.284–7.315, p < 0.001). Conclusion: Our results revealed a high prevalence, particularly seroprevalence, of C. trachomatis among women with infertility. Furthermore, we found an association between C. trachomatis omp1 sense mutations and CIN. Therefore, C. trachomatis serves as a risk factor for CIN. [ABSTRACT FROM AUTHOR]

The article discusses the 2023 Consensus statement on doxycycline prophylaxis (doxy-PEP) for the prevention of syphilis, chlamydia, and gonorrhea among gay, bisexual, and other men who have sex with men (GBMSM) in Australia. It highlights the potential benefits of doxy-PEP in reducing syphilis incidence but raises concerns about increasing antimicrobial resistance (AMR) and the need for effective monitoring of doxy-PEP use. The article compares doxy-PEP to HIV pre-exposure prophylaxis (PrEP) and emphasizes the differences in effectiveness and potential risks. It also discusses the impact of doxy-PEP on antimicrobial stewardship, resistance, and the microbiome. The article concludes by suggesting that caution should be exercised in supporting and implementing doxy-PEP and recommends comprehensive counseling and antimicrobial stewardship programs. The text discusses opportunities to enhance surveillance of sexually transmitted infections (STIs), antimicrobial resistance (AMR), and antimicrobial use. The authors support nine recommendations for research, guidelines, and policy, including the need for adequate funding and monitoring of AMR. They suggest implementing standardized data collection methods and interoperable systems to improve understanding of the drivers of resistance. The authors also emphasize the importance of access to STI testing, including AMR testing, and the need for comprehensive surveillance systems to monitor the impact of doxy-PEP use. [Extracted from the article]

Background: The Alliance for the Global Elimination of Trachoma (GET) endorses the full SAFE strategy to eliminate trachoma; Surgery (for trichiasis), Antibiotics (to reduce the community pool of infection, Facial cleanliness, and Environmental improvement (to decrease transmission). There is no accepted measure of facial cleanliness. This study compared two possible metrics for facial cleanliness. Method/Findings: Metric one: Clean face was defined as observed absence of ocular and nasal discharge on the face. Metric two: observing a grade of dirtiness (scale 10 = lightest to 0 = darkest) on a standard facial wipe. The reliability of grading a child's face or grading a facial wipe was determined in children in Kongwa Tanzania. We also observed both measurements in a cohort of 202 children ages 1 to <7years prior to face cleaning, immediately afterwards, and 4 hours afterwards. Fifty of the children did not have face cleaning and were controls. Intra-and interobserver reliability was similar for both measures, the latter = 0.53 for observing a clean face and 0.52 for grading a facial wipe. There was no correlation between the two. Both measures detected facial cleaning, compared to control children who were not cleaned, immediately after cleaning; control children with 53% clean faces and wipe score of 6.7 compared to cleaned children with 88% clean faces and wipe score of 8 (p =.0001, p = <.0001, respectively). Both measures also detected face washing 4 hours previously compared to controls. Conclusions: The two metrics were equally reliable, and both measured the behavior of face washing. They measure different aspects of a clean face; one measures the amount of dirt on wiped area and the other measures ocular and nasal discharge. Both measurements appear to capture the behavior of facial cleaning, and the choice of metric would appear to rest on the measurement that captures the stated objective of the behavior, consideration of costs, training, logistics, and implementation. Author summary: Trachoma, a chronic ocular infection caused by Chlamydia trachomatis, is the leading infectious cause of blindness globally. The full SAFE strategy is implemented by affected countries to eliminate trachoma; Surgery (for trichiasis), Antibiotics (to reduce the community pool of infection, Facial cleanliness, and Environmental improvement (to decrease transmission). However, there is no accepted measure of facial cleanliness that programs can use to chart progress in improving hygiene. This study compared two possible metrics for facial cleanliness, observing a clean face and observing dirt on a facial wipe. A clean face was defined as observed absence of ocular and nasal discharge on the face or observing a low grade of dirtiness (scale 10 = white to 0 = black) on a standard facial wipe. The reliability of grading a child's face or grading a facial wipe was determined in children in Kongwa Tanzania. Both measurements were equally reliable. We tested both measures in a cohort of 202 children ages 1 to <7years prior to face cleaning, immediately afterwards, and 4 hours afterwards. There was no correlation between the two. Both measures detected facial cleaning immediately after cleaning, compared to control children who were not cleaned; control (uncleaned) had 53% clean faces and wipe score of 6.7 compared to cleaned children with 88% clean faces and wipe score of 8 (p =.0001, p = <.0001, respectively). Both measures also detected face washing 4 hours previously compared to controls. The two metrics were equally reliable, and both measured the behavior of face washing. They measure different aspects of a clean face; one measures dirtiness and the other measures potentially infected ocular and nasal discharge. Both measurements appear to capture the behavior of facial cleaning, and the choice of metric would appear to rest on the measurement that captures the stated objective of the behavior, consideration of costs, training, logistics, and implementation. [ABSTRACT FROM AUTHOR]

Men having sex with men (MSM) represent a key population, in which sexually transmitted rectal infections (STIs) caused by Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and high-risk HPV (HR-HPV) are very common and linked to significant morbidity. Investigating the anorectal microbiome associated with rectal STIs holds potential for deeper insights into the pathogenesis of these infections and the development of innovative control strategies. In this study, we explored the interplay at the rectal site between C. trachomatis, N. gonorrhoeae, HR-HPV infection, and the anorectal microbiome in a cohort of 92 MSM (47 infected by CT and/or NG vs 45 controls). Moreover, we assessed the presence of Torquetenovirus (TTV), a non-pathogenic endogenous virus, considered as a possible predictor of immune system activation. We found a high prevalence of HR-HPV rectal infections (61%), especially in subjects with a concurrent CT/NG rectal infection (70.2%) and in people living with HIV (84%). In addition, we observed that TTV was more prevalent in subjects with CT/NG rectal infections than in non-infected ones (70.2% vs 46.7%, respectively). The anorectal microbiome of patients infected by CT and/or NG exhibited a reduction in Escherichia, while the presence of TTV was significantly associated with higher levels of Bacteroides. We observed a positive correlation of HR-HPV types with Escherichia and Corynebacterium, and a negative correlation with the Firmicutes phylum, and with Prevotella, Oscillospira, Sutterella. Our findings shed light on some of the dynamics occurring within the rectal environment involving chlamydial/gonococcal infections, HPV, TTV, and the anorectal microbiome. These data could open new perspectives for the control and prevention of STIs in MSM. [ABSTRACT FROM AUTHOR]

Introduction: Of the many sexually transmitted pathogens, Chlamydia trachomatis is increasingly being associated with long-term sequelae such as infertility, apart from causing genital tract infections. Many inflammatory responses directed against chlamydial infection can cause tubal damage resulting in infertility. For example, chlamydial heat shock protein 60 (cHSP60) and cHSP10 along with humoral immune response. The aim of our study is to detect the presence of immunoglobulin G (IgG) antibodies against Major Outer Membrane Protein (MOMP), cHSP60, and cHSP10 among female infertility. Methods: A total number of 230 female infertility patients attending the Outpatient Department of Reproductive Medicine, SRIHER, were included in the study. Detailed history documented in the proforma. Serological detection of C. trachomatis IgG antibody against MOMP, cHSP60, and cHSP10 antibody was done by enzyme-linked immunosorbent assay (ELISA). Results: C. trachomatis IgG antibody against MOMP was detected in 15 (6.5%) of 230 females. High seropositivity to cHSP60 antibodies was detected among females of tubal factor infertility (TFI). Our study showed that cHSP60 antibodies (3.4%) were more common than cHSP10 (2.6%). Conclusion: Our study suggest cHSP60 or cHSP10 antibody detection by ELISA along with TFI is helpful for diagnosis and early institution of therapy. The accuracy of TFI prediction could be increased by the detection of anti-MOMP and cHSP60 over cHSP10 among secondary infertility than primary. The most probable reason for high seropositivity among secondary infertility patients may be due to repeated infection and chronicity because of longer active sexual life. [ABSTRACT FROM AUTHOR]

4-Chloroisocoumarin compounds have broad inhibitory properties against serine proteases. Here, we show that selected 3-alkoxy-4-chloroisocoumarins preferentially inhibit the activity of the conserved serine protease High-temperature requirement A of Chlamydia trachomatis. The synthesis of a new series of isocoumarin-based scaffolds has been developed, and their anti-chlamydial properties were investigated. The structure of the alkoxy substituent was found to influence the potency of the compounds against High-temperature requirement A, and modifications to the C-7 position of the 3-alkoxy-4-chloroisocoumarin structure attenuate anti-chlamydial properties. [ABSTRACT FROM AUTHOR]

Background: Chlamydia trachomatis is the commonest cause of bacterial sexually transmitted infections. This research aimed at scrutinizing the Chlamydia trachomatis screening tests with vaginal samples and at investigating the correlation between Chlamydia trachomatis infection and the abortion incidence. Methods: The current Cross sectional study was done at gynecology clinic of Razi Hospital in Chalus, Iran between August 2017 and January 2018. Fifty vaginal swabs were collected and detecting C. trachomatis DNA was done. Chi-square test and Independent t-test compared the variables. P <0.001 was significant. Results: The total C. trachomatis infection prevalence was 5(10%) in endocervical swabs. A significant difference was found between duration of sexual activity and Chlamydia infection. No significant difference was detected between detection of Chlamydia l and abnormal vaginal discharged. Conclusion: Screening for Chlamydia trachomatis infection of the women experiencing a miscarriage should be done and, if positive, they should be treated to inhibit recurrent miscarriages. [ABSTRACT FROM AUTHOR]

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Obligate intracellular bacteria have remained those for which effective vaccines are unavailable, mostly because protection does not solely rely on an antibody response. Effective antibody-based vaccines, however, have been developed against extracellular bacteria pathogens or toxins. Additionally, obligate intracellular bacteria have evolved many mechanisms to subvert the immune response, making vaccine development complex. Much of what we know about protective immunity for these pathogens has been determined using infection-resolved cases and animal models that mimic disease. These studies have laid the groundwork for antigen discovery, which, combined with recent advances in vaccinology, should allow for the development of safe and efficacious vaccines. Successful vaccines against obligate intracellular bacteria should elicit potent T cell memory responses, in addition to humoral responses. Furthermore, they ought to be designed to specifically induce strong cytotoxic CD8+ T cell responses for protective immunity. This review will describe what we know about the potentially protective immune responses to this group of bacteria. Additionally, we will argue that the novel delivery platforms used during the Sars-CoV-2 pandemic should be excellent candidates to produce protective immunity once antigens are discovered. We will then look more specifically into the vaccine development for Rickettsiaceae, Coxiella burnetti, and Anaplasmataceae from infancy until today. We have not included Chlamydia trachomatis in this review because of the many vaccine related reviews that have been written in recent years. [ABSTRACT FROM AUTHOR]

Purpose: To detect otherwise undiagnosed asymptomatic sexually transmitted infection (STI), and for estimating prevalence among men who have sex with men (MSM). Methods: In this community-based study in Hong Kong, adult MSM were recruited. After completion of an online survey, free multi-anatomic sites self-sampling kits (urine specimens, pharyngeal and rectal swabs) for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) tests were delivered to requesting participants. Factors associated with STI positivity were analyzed in logistic regression. Results: From September 2021 to October 2022, 712 MSM were recruited, with 86% aged 18–39, and 16% reported history of chemsex engagement. A majority (81%) had previously undergone HIV testing, 68% had ever tested for STI, and 35% previously diagnosed with STI. Totally 428 (60%) had requested self-sampling kits, and 276 (39%) returned collected samples. Among participants who returned the samples, about half had never been tested in the past and had no history of STI. Overall 21% tested positive for CT and/or NG (CT/NG)—CT positive 16% and NG positive 7%. By anatomic site, 16% of rectal swabs, 7% of pharyngeal swabs, but just 3% of urine specimens were CT/NG positive. The prevalence of CT/NG was not significantly different by history of STI diagnosis and testing. Conclusion: Self-sampled STI testing is a potentially useful means for enhancing uptake of screening in MSM in the community, which could uncover otherwise undiagnosed asymptomatic infections. Internet-based self-sampling for STI testing could complement the current clinic-based STI testing for supporting epidemiologic evaluation of STI control in the community. [ABSTRACT FROM AUTHOR]

Chlamydia trachomatis (Ct) infections are the most common sexually transmitted infection (STI). Despite effective antibiotics for Ct, undetected infections or delayed treatment can lead to infertility, ectopic pregnancies, and chronic pelvic pain. Besides humans, chlamydia poses similar health challenges in animals such as C. suis (Cs) in pigs. Based on the similarities between humans and pigs, as well as their chlamydia species, we use pigs as a large biomedical animal model for chlamydia research. In this study, we used the pig model to develop a vaccine candidate against Ct. The vaccine candidate consists of TriAdj-adjuvanted chlamydial-protease-like activity factor (CPAF) protein. We tested two weekly administration options—twice intranasal (IN) followed by twice intramuscular (IM) and twice IM followed by twice IN. We assessed the humoral immune response in both serum using CPAF-specific IgG (including antibody avidity determination) and also in cervical and rectal swabs using CPAF-specific IgG and IgA ELISAs. The systemic T-cell response was analyzed following in vitro CPAF restimulation via IFN-γ and IL-17 ELISpots, as well as intracellular cytokine staining flow cytometry. Our data demonstrate that while the IN/IM vaccination mainly led to non-significant systemic immune responses, the vaccine candidate is highly immunogenic if administered IM/IN. This vaccination strategy induced high serum anti-CPAF IgG levels with strong avidity, as well as high IgA and IgG levels in vaginal and rectal swabs and in uterine horn flushes. In addition, this vaccination strategy prompted a pronounced cellular immune response. Besides inducing IL-17 production, the vaccine candidate induced a strong IFN-γ response with CD4 T cells. In IM/IN-vaccinated pigs, these cells also significantly downregulated their CCR7 expression, a sign of differentiation into peripheral-tissue-homing effector/memory cells. Conclusively, this study demonstrates the strong immunogenicity of the IM/IN-administered TriAdj-adjuvanted Ct CPAF vaccine candidate. Future studies will test the vaccine efficacy of this promising Ct vaccine candidate. In addition, this project demonstrates the suitability of the Cs pre-exposed outbred pig model for Ct vaccine development. Thereby, we aim to open the bottleneck of large animal models to facilitate the progression of Ct vaccine candidates into clinical trials. [ABSTRACT FROM AUTHOR]

There is an urgent need to produce a vaccine for Chlamydia trachomatis infections. Here, using the Chlamydia muridarum major outer membrane protein (MOMP) as an antigen, four adjuvant combinations IVAX-1 (MPLA+CpG-1018+AddaVax), IVAX-2 (MPLA+CpG-1018+AS03), CpG-1826+Montanide ISA 720 VG (CpG-1826+Mont) and CpG-1018+Montanide ISA 720 VG (CpG-1018+Mont), were tested for their local reactogenicity and ability to elicit protection in BALB/c mice against a respiratory challenge with C. muridarum. Immunization with IVAX-1 or IVAX-2 induced no significant local reactogenicity following intramuscular immunization. In contrast, vaccines containing Montanide resulted in the formation of a local granuloma. Based on the IgG2a/IgG1 ratio in serum, the four adjuvant combinations elicited Th1-biased responses. IVAX-1 induced the highest in vitro neutralization titers while CpG-1018+Mont stimulated the lowest. As determined by the levels of IFN-γ produced by T-cells, the most robust cellular immune responses were elicited in mice immunized with CpG-1018+Mont, while the weakest responses were mounted by mice receiving IVAX-1. Following the respiratory challenge, mice immunized with CpG-1018+Mont lost the least amount of body weight and had the lowest number of C. muridarum inclusion-forming units (IFUs) in the lungs, while those receiving IVAX-2 had lost the most weight and had the highest number of IFUs in their lungs. Animals vaccinated with CpG-1826+Mont had the lightest lungs while those immunized using IVAX-2 had the heaviest. To conclude, due to their safety and adjuvanticity, IVAX formulations should be considered for inclusion in human vaccines against Chlamydia.

Trachoma, caused by ocular Chlamydia trachomatis infection, is targeted for global elimination as a public health problem by 2030. To provide evidence for use of antibodies to monitor C. trachomatis transmission, we collated IgG responses to Pgp3 antigen, PCR positivity, and clinical observations from 19,811 children aged 1-9 years in 14 populations. We demonstrate that age-seroprevalence curves consistently shift along a gradient of transmission intensity: rising steeply in populations with high levels of infection and active trachoma and becoming flat in populations near elimination. Seroprevalence (range: 0-54%) and seroconversion rates (range: 0-15 per 100 person-years) correlate with PCR prevalence (r: 0.87, 95% CI: 0.57, 0.97). A seroprevalence threshold of 13.5% (seroconversion rate 2.75 per 100 person-years) identifies clusters with any PCR-identified infection at high sensitivity ( >90%) and moderate specificity (69-75%). Antibody responses in young children provide a robust, generalizable approach to monitor population progress toward and beyond trachoma elimination.

BackgroundThe Centers for Disease Control and Prevention recommends that men who have sex with men (MSM) get tested annually for urethral and rectal chlamydia (CT) and gonorrhea (NG), and pharyngeal NG. There are no national recommendations to screen women and heterosexual men at extragenital sites. We assessed extragenital CT/NG screening among men and women at Louisiana's Parish Health Units (PHU).MethodsThe Louisiana STD/HIV/Hepatitis Program piloted extragenital screening at 4 PHUs in February 2016 and expanded to 11 PHUs in 2017. Sexual histories were used to identify gender of sex partners and exposed sites. Because of billing restrictions, up to 2 anatomical sites were tested for CT/NG.ResultsFrom February 2016 to June 2019, 70,895 urogenital and extragenital specimens (56,086 urogenital, 13,797 pharyngeal, and 1,012 rectal) were collected from 56,086 patients. Pharyngeal CT positivity was 160 of 7,868 (2.0%) among women, 54 of 4,838 (1.1%) among men who have sex with women (MSW) and 33 of 1,091 (3.0%) among MSM. Rectal CT positivity was 51 of 439 (11.6%) among women and 95 of 573 (16.6%) among MSM. Pharyngeal NG positivity was 299 of 7,868 (3.8%) among women, 222 of 4,838 (4.6%) among MSW, and 97 of 1,091 (8.9%) among MSM. Rectal NG positivity was 20 of 439 (4.6%) among women and 134 of 573 (23.4%) among MSM.Urogenital-only screening would have missed: among women, 173 of 3,923 (4.4%) CT and 227 of 1,480 (15.3%) NG infections; among MSW, 26 of 2,667 (1%) CT and 149 of 1,709 (8.7%) NG infections; and among MSM, 116 of 336 (34.5%) CT and 127 of 413 (42.1%) NG infections.ConclusionsMany CT/NG infections would have been missed with urogenital-only screening. Men who have sex with men had much higher extragenital infection rates than women and MSW.

BackgroundContinued high incidence of HIV and other STIs, paired with rising antibiotic resistance to a number of existing treatments, warrants the development of new pharmaceutical approaches for STI prevention. Multipurpose prevention technologies (MPTs) offer an innovative approach for expanding HIV/STI prevention. The majority of MPT product candidates currently in development include HIV prevention, while only half include compounds active against non-HIV STIs.MethodsThis narrative review focuses on compounds in preclinical development (in vitro and in vivo) through phase 3 clinical trials with activity against one or more of the following infections: HIV, HSV-1, HSV-2, Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, and Trichomonas vaginalis. Bacterial vaginosis is included due to its association with increased risk of STIs. The focus is on compounds with novel mechanisms of action and prophylactic and/or therapeutic potential. Articles published in PubMed between 2011 and 2021, NIH RePorter and conference abstracts and proceedings between 2020 and 2021 were searched. Excluded from the review are compounds that are already being used in MPT product candidates.Main resultsThere is a growing pipeline of compounds targeting viral STIs, many of which have successfully transitioned from preclinical to clinical stages of development. However, the product development pipeline remains limited for compounds that target bacterial STIs.ConclusionsThe paucity of new pharmaceutical approaches for STI prevention, particularly non-HIV STIs, remains a public health gap. Future funding priorities should include STI prevention research. Despite limited attention to STI prevention in the development of MPTs, many research institutions worldwide are working on discoveries of new compounds, exploring new indications for existing drugs or on innovative drug delivery mechanisms. Our findings can be used to connect researchers across the globe to advance the development of compounds that have potential as active pharmaceutical ingredients in future MPTs.

BackgroundMethamphetamine (MA) use is associated with sexual risk behavior as well as systemic and mucosal inflammation, suggesting parallel biological and behavioral mechanisms of HIV transmission among men who have sex with men (MSM) who use MA. Data evaluating the combined biological effects of MA use with concomitant rectal gonococcal and/or chlamydial (GC/CT) infection on inflammation are limited.SettingSecondary analysis of stored rectal and plasma specimens from 100 MSM participating in an NIDA-funded longitudinal cohort in Los Angeles, CA.MethodsThis cross-sectional analysis evaluated systemic and rectal inflammatory markers under 2 conditions: (1) recent MA use (by urine drug screen) and (2) rectal GC/CT infection. We evaluated 50 participants with recent MA use (25 with and 25 without rectal GC/CT) and 50 MSM without MA use (25 with and 25 without rectal GC/CT). Log-transformed plasma and rectal immune markers were regressed on MA exposure and rectal GC/CT, controlling for HIV status and age.ResultsMedian age was 32 (range 19-45) years, and 58% of participants were living with HIV. Plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-8, IL-1ß, and rectal IL-6 were associated with rectal GC/CT and MA use, independent of HIV status. Higher levels of rectal TNF-α, IL-1ß, and IL-17a were associated with rectal GC/CT.ConclusionsSystemic and rectal inflammation was positively associated with rectal GC/CT and MA use. Condomless sex in the setting of GC/CT- and MA-induced immune activation may provide a basis for synergistic biobehavioral mechanisms that promote HIV/STI transmission among MSM who use MA.

Chlamydia are Gram-negative, obligate intracellular bacterial pathogens that infect eukaryotic cells and reside within a host-derived vacuole known as the inclusion. To facilitate intracellular replication, these bacteria must engage in host-pathogen interactions to obtain nutrients and membranes required for the growth of the inclusion, thereby sustaining prolonged bacterial colonization. Autophagy is a highly conserved process that delivers cytoplasmic substrates to the lysosome for degradation. Pathogens have developed strategies to manipulate and/or exploit autophagy to promote their replication and persistence. This review delineates recent advances in elucidating the interplay between Chlamydia trachomatis infection and autophagy in recent years, emphasizing the intricate strategies employed by both the Chlamydia pathogens and host cells. Gaining a deeper understanding of these interactions could unveil novel strategies for the prevention and treatment of Chlamydia infection.

Resumo: O objetivo deste estudo foi conhecer a opinião dos profissionais participantes da implantação-piloto de testes moleculares para detecção de Chlamydia trachomatis e Neisseria gonorrhoeae no Sistema Único de Saúde (SUS). Determinou-se a taxa de detecção de C. trachomatis e/ou N. gonorrhoeae e os fatores associados à infecção. A estratégia contou com laboratórios pertencentes à rede de carga viral de HIV e hepatites virais. A testagem teve como público-alvo pessoas mais vulnerabilizadas às infecções sexualmente transmissíveis, com coleta de amostras de urina e/ou swabs vaginal, endocervical e/ou uretral masculino. Questionários foram enviados aos gestores estaduais e profissionais de laboratório sobre a implantação-piloto. De maneira geral, as avaliações foram positivas. Entre as fraquezas, citou-se dificuldades na mudança do processo de trabalho, carência de recursos humanos, pouca sensibilidade de profissionais da assistência e ausência de tubo primário de urina, único insumo não fornecido. Como fortaleza, destaca-se aquisição centralizada de testes, compartilhamento de equipamentos e armazenamento de amostras à temperatura ambiente. Das 16.177 pessoas testadas, 1.004 (6,21%) foram positivas para C. trachomatis, 1.036 (6,4%) para N. gonorrhoeae e 239 (1,48%) para C. trachomatis/N. gonorrhoeae. A detecção de infecção ocorreu mais em pessoas jovens (≤ 24 vs. > 24 anos) (aOR = 2,65; IC95%: 2,38-2,96), do sexo masculino (aOR = 1,95; IC95%: 1,72-2,21), pardas/pretas (aOR = 1,06; IC95%: 1,05-1,11), na Região Sudeste (aOR = 1,08; IC95%: 1,02-1,13) e em amostras de secreção uretral (aOR = 1,46; IC95%: 1,41-1,52). Os resultados deste estudo demonstraram a importância da disponibilização da testagem em âmbito nacional, os quais subsidiaram a implantação da rede definitiva para detecção de C. trachomatis/N. gonorrhoeae no SUS.

ABSTRACT Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infections in the USA and of preventable blindness worldwide. This obligate intracellular pathogen replicates within a membrane-bound inclusion, but how it acquires nutrients from the host while avoiding detection by the innate immune system is incompletely understood. C. trachomatis accomplishes this in part through the translocation of a unique set of effectors into the inclusion membrane, the inclusion membrane proteins (Incs). Incs are ideally positioned at the host-pathogen interface to reprogram host signaling by redirecting proteins or organelles to the inclusion. Using a combination of co-affinity purification, immunofluorescence confocal imaging, and proteomics, we characterize the interaction between an early-expressed Inc of unknown function, Tri1, and tumor necrosis factor receptor-associated factor 7 (TRAF7). TRAF7 is a multi-domain protein with a RING finger ubiquitin ligase domain and a C-terminal WD40 domain. TRAF7 regulates several innate immune signaling pathways associated with C. trachomatis infection and is mutated in a subset of tumors. We demonstrate that Tri1 and TRAF7 specifically interact during infection and that TRAF7 is recruited to the inclusion. We further show that the predicted coiled-coil domain of Tri1 is necessary to interact with the TRAF7 WD40 domain. Finally, we demonstrate that Tri1 displaces the native TRAF7 binding partners, mitogen-activated protein kinase kinase kinase 2 (MEKK2), and MEKK3. Together, our results suggest that by displacing TRAF7 native binding partners, Tri1 has the capacity to alter TRAF7 signaling during C. trachomatis infection.IMPORTANCEChlamydia trachomatis is the leading cause of bacterial sexually transmitted infections in the USA and preventable blindness worldwide. Although easily treated with antibiotics, the vast majority of infections are asymptomatic and therefore go untreated, leading to infertility and blindness. This obligate intracellular pathogen evades the immune response, which contributes to these outcomes. Here, we characterize the interaction between a C. trachomatis-secreted effector, Tri1, and a host protein involved in innate immune signaling, TRAF7. We identified host proteins that bind to TRAF7 and demonstrated that Tri1 can displace these proteins upon binding to TRAF7. Remarkably, the region of TRAF7 to which these host proteins bind is often mutated in a subset of human tumors. Our work suggests a mechanism by which Tri1 may alter TRAF7 signaling and has implications not only in the pathogenesis of C. trachomatis infections but also in understanding the role of TRAF7 in cancer.

Background: Current clinical care for common bacterial STIs (Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Mycoplasma genitalium (MG)) involves empiric antimicrobial therapy when clients are symptomatic, or if asymptomatic, waiting for laboratory testing and recall if indicated. Near-to-patient testing (NPT) can improve pathogen-specific prescribing and reduce unnecessary or inappropriate antibiotic use in treating sexually transmitted infections (STI) by providing same-day delivery of results and treatment. Methods: We compared the economic cost of NPT to current clinic practice for managing clients with suspected proctitis, non-gonococcal urethritis (NGU), or as an STI contact, from a health provider’s perspective. With a microsimulation of 1000 clients, we calculated the cost per client tested and per STI- and pathogen- detected for each testing strategy. Sensitivity analyses were conducted to assess the robustness of the main outcomes. Costs are reported as Australian dollars (2023). Results: In the standard care arm, cost per client tested for proctitis, NGU in men who have sex with men (MSM) and heterosexual men were the highest at $247.96 (95% Prediction Interval (PI): 246.77–249.15), $204.23 (95% PI: 202.70–205.75) and $195.01 (95% PI: 193.81–196.21) respectively. Comparatively, in the NPT arm, it costs $162.36 (95% PI: 161.43–163.28), $158.39 (95% PI: 157.62–159.15) and $149.17 (95% PI: 148.62–149.73), respectively. Using NPT resulted in cost savings of 34.52%, 22.45% and 23.51%, respectively. Among all the testing strategies, substantial difference in cost per client tested between the standard care arm and the NPT arm was observed for contacts of CT or NG, varying from 27.37% to 35.28%. Conclusion: We found that NPT is cost-saving compared with standard clinical care for individuals with STI symptoms and sexual contacts of CT, NG, and MG.

Background: Rapid tests for diagnosing Chlamydia trachomatis infection can facilitate patient treatment and reduce transmission, as patients can receive treatment during the same visit. This study aims to evaluate the performance of the rapid test compared to the PCR test for diagnosing C. trachomatis infection to assess its clinical applicability. Methods: A cross-sectional study was conducted on participants aged >18 years with symptoms of genital discharge. The performance of the rapid test was evaluated using the PCR test as the gold-standard. Results: A total of 196 eligible patients were selected for the study. Females accounted for 68.4%, and those aged over 25 years represented 73.0% of the total. The prevalence of C. trachomatis infection was 14.3%. The overall return rate was 41.8%. The Chlamydia rapid test demonstrated a sensitivity of 53.6% (95% CI: 46.6–60.5%), specificity of 86.3% (95% CI: 81.5–91.1%), positive-predictive value of 39.5% (95% CI: 32.6–46.3%), and negative-predictive value of 91.8% (95% CI: 87.9–95.6%). The sensitivity of the rapid test was significantly higher in females, ≥25 years, those with past STIs, and symptoms including pruritus, dysuria, and purulent discharge than their counterparts (p

Among 98 participants with penile discharge symptoms of Chlamydia trachomatis or Neisseria gonorrhoeae at a walk-in sexual health clinic, 11 were diagnosed with Mycoplasma genitalium , 10 had antibiotic resistance, and 6 were incorrectly presumptively treated. Our findings highlight the importance of public health strategies and research to curb M genitalium. [ABSTRACT FROM AUTHOR]

BackgroundMass administration of azithromycin is an established strategy for decreasing the prevalence of trachoma in endemic areas. However, nearby untreated communities could serve as a reservoir that may increase the chances of chlamydia reinfection in treated communities.MethodsAs part of a cluster-randomized trial in Ethiopia, 60 communities were randomized to receive mass azithromycin distributions and 12 communities were randomized to no treatments until after the first year. Ocular chlamydia was assessed from a random sample of children per community at baseline and month 12. Distances between treated and untreated communities were assessed from global positioning system coordinates collected for the study.ResultsThe pretreatment prevalence of ocular chlamydia among 0 to 9 year olds was 43% (95% confidence interval [CI], 39%-47%), which decreased to 11% (95% CI, 9%-14%) at the 12-month visit. The posttreatment prevalence of chlamydia was significantly higher in communities that were closer to an untreated community after adjusting for baseline prevalence and the number of mass treatments during the year (odds ratio, 1.12 [95% CI, 1.03-1.22] for each 1 km closer to an untreated community).ConclusionsMass azithromycin distributions to wide, contiguous geographic areas may reduce the likelihood of continued ocular chlamydia infection in the setting of mass antibiotic treatments.

IntroductionChlamydia trachomatis, a gram-negative obligate intracellular bacterium, commonly causes sexually transmitted infections (STIs). Little is known about C. trachomatis transmission within the host, which is important for understanding disease epidemiology and progression.MethodsWe used RNA-bait enrichment and whole-genome sequencing to compare rectal, vaginal and endocervical samples collected at the same time from 26 study participants who attended Fijian Ministry of Health and Medical Services clinics and tested positive for C. trachomatis at each anatomic site.ResultsThe 78 C. trachomatis genomes from participants resolved into two major clades of the C. trachomatis phylogeny (the "prevalent urogenital and anorectal" clade and "non-prevalent urogenital and anorectal" clade). For 21 participants, genome sequences were almost identical in each anatomic site. For the other five participants, two distinct C. trachomatis strains were present in different sites; in two cases, the vaginal sample was a mixture of strains.DiscussionThe absence of large numbers of fixed SNPs between C. trachomatis genomes within many of the participants could indicate recent acquisition of infection prior to the clinic visit without sufficient time to accumulate significant genetic variation in different body sites. This model suggests that many C. trachomatis infections may be resolved relatively quickly in the Fijian population, possibly reflecting common prescription or over-the-counter antibiotics usage.