Update on the Epidemiology, Screening, and Management of Chlamydia trachomatis Infection

Sexually transmitted infections in the middle east and North Africa: comprehensive systematic review and meta-analysis

BACKGROUND

Globally, sexually transmitted infections (STIs) collectively cause 2.3 million deaths and 1.2 million cases of cancer annually. However, the epidemiology of STIs in the Middle East and North Africa (MENA) is not well assessed because of various social and cultural factors.

METHODS

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and covering 23 MENA countries, 19 STIs, and data from 20,435,971 participants. PubMed, Embase, regional and international databases, and country-level reports were searched up to May 2024.

RESULTS

The analysis revealed significant regional variations in the prevalence of STIs within the MENA region. In North Africa, the most common STIs were bacterial vaginosis (31%), human papillomavirus (HPV, 23%), and Candida spp. (15%). In the Gulf Cooperation Council region and Yemen, Ureaplasma (25%), nongonococcal urethritis (NGU, 16%), and Mycoplasma spp. (12%) were the predominant infections. In the Levant region, the top STIs were HPV (20%), hepatitis B virus (HBV, 9%), and Candida spp. (9%). In Iran, Ureaplasma spp. (18%), HPV (17%), and cytomegalovirus (8%) were the most prevalent infections, whereas Ureaplasma spp. (20%), Candida spp. (18%), and HPV (16%) were most frequently detected in Türkiye. Gender-based disparities were observed, with a higher prevalence of Ureaplasma spp., Neisseria gonorrhoeae, and herpes in men and higher rates of Mycoplasma spp., HPV, HBV, and Candida spp. in women. Overall, high rates of nongonococcal urethritis (16.3%), Ureaplasma spp. (13.7%), HPV (12.7%), and Candida spp. (9.4%) were recorded in the MENA region.

CONCLUSIONS

Most MENA countries lack national STI screening programs, and the reported data are primarily from symptomatic individuals. Establishing robust surveillance systems, addressing stigma and barriers to healthcare access, and expanding STIs screening and vaccination programs are crucial for accurately capturing the true burden of STIs in MENA countries.

Association Between Self-Reported Infections and Seropositivity Among Pregnant Women With Gastroschisis: A Case Control Study, With Emphasis on Chlamydia trachomatis

BACKGROUND

Gastroschisis is a birth defect with the greatest risk among women <20 years of age.

METHODS

Pregnant women attending the University of Utah's Maternal-Fetal Medicine Diagnostic Center between 2011 and 2017 for either their routine diagnostic ultrasound or referral were recruited (cases: pregnant women with fetal gastroschisis, n = 53 participated/57, 93%; controls: pregnant women without fetal abnormalities, n = 102 participated/120, 85%). A clinic coordinator consented and interviewed women and obtained a blood sample and prenatal medical records. We evaluated self-reported maternal characteristics, risk factors, and infections. To assess pathogen seropositivity we used Serimmune's Serum Epitope Repertoire Analysis validated 35 pathogen panels and Chlamydia trachomatis and compared seropositivity to self-report and prenatal medical record screening to assess sensitivity.

RESULTS

Cases were more likely to report a younger age at sexual debut (p = <0.01), more sexual partners (p = 0.02), being unmarried (p < 0.01), changing partners between pregnancies (p = <0.01), smoking cigarettes (<0.01), and a recent sexually transmitted infection (STI) (p = 0.02). No differences were observed for self-report of illicit drug use or periconceptional urinary tract infections. Cases had a higher seropositivity for cytomegalovirus (p = 0.01). No differences were observed for herpes simplex I, II, or Epstein-Barr. Though based on small numbers, C. trachomatis seropositivity was highest in cases (17%) compared to controls (8.8%) with the highest proportion observed in case women <20 years of age (cases 33%; controls 0%). Any STI (self-report or seropositivity) was also highest among cases <20 years of age (cases 47%; controls 0%). Among C. trachomatis seropositive women, self-report and prenatal medical record sensitivity was 27.8% and 3%, respectively.

CONCLUSIONS

Cases were more likely to engage in behaviors that can increase their risk of exposure to sexually transmitted pathogens. Case women <20 years of age had the highest proportion of C. trachomatis seropositivity and any STI. Prenatal medical records and self-report were inadequate to identify a recent chlamydial infection whereas, the SERA assay is a novel approach for evaluating subclinical infections that may impact the developing embryo.

The Chlamydia effector IncE employs two short linear motifs to reprogram host vesicle trafficking

Chlamydia trachomatis, a leading cause of bacterial sexually transmitted infections, creates a specialized intracellular replicative niche by translocation and insertion of a diverse array of effectors (Incs [inclusion membrane proteins]) into the inclusion membrane. Here, we characterize IncE, a multifunctional Inc that encodes two non-overlapping short linear motifs (SLiMs) within its short cytosolic C terminus. The proximal SLiM, by mimicking just a small portion of an R-N-ethylmaleimide-sensitive factor adaptor protein receptor (SNARE) motif, binds and recruits syntaxin (STX)7- and STX12-containing vesicles to the inclusion. The distal SLiM mimics the sorting nexin (SNX)5 and SNX6 cargo binding site to recruit SNX6-containing vesicles to the inclusion. By simultaneously binding two distinct vesicle classes, IncE brings these vesicles in close apposition with each other at the inclusion to facilitate C. trachomatis intracellular development. Our work suggests that Incs may have evolved SLiMs to enable rapid evolution in a limited protein space to disrupt host cell processes.

Chlamydia in pigs: intriguing bacteria associated with sub-clinical carriage and clinical disease, and with zoonotic potential

Chlamydiae are bacteria that are intriguing and important at the same time. The genus Chlamydia encompasses many species of obligate intracellular organisms: they can multiply only inside the cells of their host organism. Many, perhaps most animals have their own specifically adapted chlamydial species. In humans, the clinically most relevant species is Chlamydia trachomatis, which has particular importance as an agent of sexually transmitted disease. Pigs are the natural host of Chlamydia suis but may also carry Chlamydia abortus and Chlamydia pecorum. C. abortus and possibly C. suis have anthropozoonotic potential, which makes them interesting to human medicine, but all three species bring a substantial burden of disease to pigs. The recent availability of genomic sequence comparisons suggests adaptation of chlamydial species to their respective hosts. In cell biological terms, many aspects of all the species seem similar but non-identical: the bacteria mostly replicate within epithelial cells; they are taken up by the host cell in an endosome that they customize to generate a cytosolic vacuole; they have to evade cellular defences and have to organize nutrient transport to the vacuole; finally, they have to organize their release to be able to infect the next cell or the next host. What appears to be very difficult and challenging to achieve, is in fact a greatly successful style of parasitism. I will here attempt to cover some of the aspects of the infection biology of Chlamydia, from cell biology to immune defence, epidemiology and possibilities of prevention. I will discuss the pig as a host species and the species known to infect pigs but will in particular draw on the more detailed knowledge that we have on species that infect especially humans.

Addressing Challenges in Chlamydia trachomatis Detection: A Comparative Review of Diagnostic Methods

Chlamydial infections are one of the most common sexually transmitted bacterial infections worldwide, which is related to serious consequences for the mental, sexual, and reproductive health of women and men. The infection is commonly asymptomatic; consequently, screening programs for infection control have been introduced in some countries. The detection methods of Chlamydia trachomatis infections have evolved since the establishment of the first gold-standard detection method in the 1970s, the culture assay. Over the decades, many efforts were made to find methods with a higher sensitivity, until the 1990s, when, as a result of advances in molecular biology, nucleic acid amplification tests came into use with more sensitivity, and, currently, there are several available with which to detect infection. Therefore, herein, we will review the main methods used for CT detection and the differences between them, in terms of targets, infections that can be detected, sensitivity, and specificity. We will focus on some of the FDA-approved CT detection tests and highlight the major advantages and superiority of using molecular biology techniques. In addition, we will examine the larger challenges and limitations of the methods currently in use and discuss how they might be surpassed. Moreover, in this review, we will describe the next step to carry out after testing positive for CT infection.

Antimicrobial treatment and resistance in sexually transmitted bacterial infections

Sexually transmitted infections (STIs) have been part of human life since ancient times, and their symptoms affect quality of life, and sequelae are common. Socioeconomic and behavioural trends affect the prevalence of STIs, but the discovery of antimicrobials gave hope for treatment, control of the spread of infection and lower rates of sequelae. This has to some extent been achieved, but increasing antimicrobial resistance and increasing transmission in high-risk sexual networks threaten this progress. For Neisseria gonorrhoeae, the only remaining first-line treatment (with ceftriaxone) is at risk of becoming ineffective, and for Mycoplasma genitalium, for which fewer alternative antimicrobial classes are available, incurable infections have already been reported. For Chlamydia trachomatis, in vitro resistance to first-line tetracyclines and macrolides has never been confirmed despite decades of treatment of this highly prevalent STI. Similarly, Treponema pallidum, the cause of syphilis, has remained susceptible to first-line penicillin.

Codesign and Launch of 'On the Ball': An Inclusive Community-Based 'Testicular Awareness' Campaign

INTRODUCTION

Increased awareness of testicular diseases can lead to early diagnosis. Evidence suggests that men's awareness of testicular diseases is low, with many expressing their willingness to delay help-seeking for symptoms of concern. The risk of testicular diseases is higher in gender and sexual minority groups. In this study, we discuss the codesign, refinement and launch of 'On the Ball', an inclusive community-based 'testicular awareness' campaign.

METHODS

The World Café participatory research methodology was used. Individuals from Lesbian, Gay, Bisexual, Transgender and Queer+ friendly organisations, testicular cancer survivors, policymakers, media/marketing experts and graphic designers were recruited. Participants were handed a brief for 'On the Ball', which was designed based on feedback from a previous World Café workshop. They were assigned to three tables. Participants rotated tables at random for three 20-min rounds of conversations. Each table had a facilitator who focussed on one element of the campaign brief. Data were collected using audio recorders and in writing and were analysed thematically.

RESULTS

Thirteen individuals participated in the workshop. The following themes emerged from the data: (i) campaign identity, (ii) campaign delivery and (iii) campaign impact. Participants recommended enhancements to the campaign logo, slogan, social media posts and poster. They suggested delivering the campaign online via social media and offline using various print and broadcast media. Participants recommended targeting areas with a large number of men such as workplaces. To help measure the impact of the campaign, participants proposed capturing social media analytics and tracking statistics relating to testicular diseases. Recommendations were used to refine the 'On the Ball' campaign and launch it in a university. In total, 411 students engaged with the various elements of the campaign during the soft launch.

CONCLUSIONS

'On the Ball' campaign visuals ought to be inclusive. Online and offline campaign delivery is warranted to reach out to a wider cohort. Campaign impact can be captured using social media analytics as well as measuring clinical outcomes relating to testicular diseases. Future research is needed to implement the campaign online and offline, explore its impact and evaluate its feasibility, acceptability, cost and effect on promoting testicular awareness.

PATIENT OR PUBLIC CONTRIBUTION

The 'On the Ball' campaign was codesigned and refined with members of Lesbian, Gay, Bisexual, Transgender and Queer+ friendly organisations, testicular cancer survivors, health policymakers, media and marketing experts and graphic designers using the World Café participatory research methodology.

The Chlamydia effector IncE employs two short linear motifs to reprogram host vesicle trafficking

Chlamydia trachomatis, a leading cause of bacteria sexually transmitted infections, creates a specialized intracellular replicative niche by translocation and insertion of a diverse array of effectors (Incs) into the inclusion membrane. Here, we characterize IncE, a multi-functional Inc that encodes two non-overlapping short linear motifs (SLiMs) within its short cytosolic C-terminus. The proximal SLiM mimics an R-SNARE motif to recruit syntaxin (STX) 7 and 12-containing vesicles to the inclusion. The distal SLiM mimics the Sorting Nexin (SNX) 5 and 6 cargo binding site to recruit SNX6-containing vesicles to the inclusion. By simultaneously binding to two distinct vesicle classes, IncE reprograms host cell trafficking to promote the formation of a class of hybrid vesicles at the inclusion that are required for C. trachomatis intracellular development. Our work suggests that Incs may have evolved SLiMs to facilitate rapid evolution in a limited protein space to disrupt host cell processes.

Characteristics of reproductive tract infections caused by common pathogens among the outpatients of reproductive medicine center in Putian: retrospective study

BACKGROUND

This study aims to explore the infection and age distribution of Ureaplasma urealyticum (UU), Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Herpes simplex virus type II (HSV II) among the outpatients of Reproductive Medicine Center in Putian, Fujian Province to provide a clinical basis for the early diagnosis and treatment of various reproductive tract diseases and infertility in this region.

METHODS

A total of 1736 samples of secretions and exfoliated cervical cells were collected from the outpatients of the Reproductive Medicine Center of the Affiliated Hospital of Putian University from December 2021 to April 2023. The infections of UU, CT, NG and HSVII were detected by real-time fluorescence polymerase chain reaction (PCR), and the infection statuses of the patients with different genders, ages and diagnoses were analysed.

RESULTS

Among the 1736 patients, 611 were male and 1125 were female. The male patients had higher UU infection rate but lower HSV II infection rate than the female patients. No significant difference in CT and NG infection rates was observed between the genders. The CT infection rate gradually decreased with the increase in the age. The difference in UU, NG and HSV II infection rates among the different age groups was not statistically significant. For UU infection, the male infertile patients had the highest rate of 37.72% (172/456). Meanwhile, the differences in CT, NG and HSV II infection rates among the different diagnosis groups were not statistically significant. Among the male and female infertile patients, the CT infection rate was the highest in the 21-25 years of age group at 11.11% (2/18) and 9.47% (9/95), respectively. No statistically significant difference in UU, CT, NG and HSV II infection rates was observed among the different age groups of patients diagnosed in relation to the family planning guidance and between the male and female patients with other diagnoses results.

CONCLUSIONS

This study showed that UU was the most frequently identified pathogen in infertile men in Putian, Fujian Province. The CT infection rate was the highest in people under 20 years old, and the infection showed a tendency toward young individuals. Therefore, the publicity of sexual health knowledge must be strengthened, and the prevention and treatment of venereal diseases among young and middle-aged people must be improved. Moreover, the pathogen infection is related to infertility to a certain extent, which is conducive to clinical diagnosis and treatment.

STI pathogens in the oropharynx: update on screening and treatment

PURPOSE OF REVIEW

The rise in antimicrobial resistance in several STI pathogens such as Neisseria gonorrhoeae has become a public health threat as only one first-line treatment remains. Reducing screening interval for gonorrhoea and chlamydia in high-prevalence populations has been proposed to address antimicrobial stewardship, but this remains controversial. This review aimed to revisit the epidemiology of infections at the oropharynx and review the current screening recommendations and treatment guidelines in different populations.

RECENT FINDINGS

Emerging evidence suggests that the oropharynx is the primary anatomical site for gonorrhoea transmission but maybe not for chlamydia transmission. Most international guidelines recommend 3-monthly oropharyngeal gonorrhoea and chlamydia screening for high-prevalence populations (e.g. men who have sex with men) but not low-prevalence populations (e.g. heterosexuals) given the clinical and public health benefits of screening in low-prevalence populations are still unclear. Doxycycline remains the first-line treatment for oropharyngeal chlamydia in most guidelines. However, some countries have moved from dual therapy (ceftriaxone and azithromycin) to monotherapy (ceftriaxone) for oropharyngeal gonorrhoea treatment to address antimicrobial stewardship.

SUMMARY

The transmission of gonorrhoea and chlamydia is still not fully understood. Further work will be required to evaluate the benefits and harms of reducing screening in high-prevalence populations.

Promoting 'testicular awareness': Co-design of an inclusive campaign using the World Café Methodology

INTRODUCTION

Testicular cancer is the most common cancer in men aged 15-44 years in many countries. Most men with testicular cancer present with a lump. Testicular symptoms are more likely to occur secondary to benign diseases like epididymo-orchitis, a common sexually transmitted infection. Gender and sexual minorities are at an increased risk of testicular diseases and health disparities. The aim of this study was to co-design an inclusive community-based campaign to promote testicular awareness.

METHODS

This study uses the World Café methodology. Participation was sought from Lesbian, Gay, Bisexual, Transgender and Queer+ friendly organisations, testicular cancer survivors, health policy makers, media and marketing experts and graphic designers. Participants engaged in three rounds of conversations to co-design the campaign. Data were collected using drawing sheets, artefact cards, sticky notes, coloured markers and a voice recorder. Deductive thematic analysis was conducted.

RESULTS

Seventeen individuals participated in the study. Six themes emerged from the analysis as follows: (i) online communication; (ii) offline communication; (iii) behavioural targeting and education; (iv) campaign frequency and reach; (v) demographic segmentation; and (vi) campaign identity. The use of social media for campaign delivery featured strongly in all conversations. Participants also recommended offline communication using posters and radio/television advertisements to scale up the campaign and achieve wider reach. Advertisements to overcome embarrassment surrounding testicular health were particularly recommended. Participants emphasised that campaign delivery must be dynamic whilst ensuring that the health-promoting messages are not diluted or lost. They stressed the importance of being inclusive and tailoring the campaign to different age groups, gender identities and sexual orientations.

CONCLUSIONS

Study recommendations will be used to design and deliver the campaign. Future research will be needed to evaluate the feasibility, acceptability, cost and effect of the campaign on promoting testicular awareness and early detection of testicular diseases.

PATIENT OR PUBLIC CONTRIBUTION

A participatory research approach was used to co-design the campaign with members of Lesbian, Gay, Bisexual, Transgender and Queer+ (LGBTQ+) friendly organisations, LGBTQ+ student bodies, LGBTQ+ staff networks, LGBTQ+ sports clubs, men's health organisations, testicular cancer survivors, health policy makers, media and marketing experts and graphic designers.

User experiences of an AI application for predicting risk of sexually transmitted infections

Objective

Awareness of one's individual risk of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) is a necessary precursor to engagement with prevention strategies and sexual health care. Web-based sexual health applications may improve engagement in sexual health prevention and care by providing individualised and evidence-based sexual health information. The STARTOnline (Supporting Timely and Appropriate Review and Treatment Online) study sought the views of sexual health service users on three web-based sexual health applications to better understand their usefulness, acceptability and accessibility. This paper reports the views and experiences of users of one of the applications called MySTIRisk. MySTIRisk estimates the risk of three common STIs and HIV using data from attendees of a metropolitan sexual health service.

Methods

This study used a bespoke qualitative design, informed by a developmental evaluation approach. Melbourne Sexual Health Centre clinic attendees' views were sought using semi-structured interviews conducted between October 2023 and January 2024 via videoconferencing, telephone and on site at the clinic. Data was analysed using qualitative data analysis methods.

Results

A diverse group of 14 participants described an ideal pathway to better sexual health outcomes that might be facilitated by use of the MySTIRisk application, particularly for individuals with limited sexual health knowledge, or affected by stigma and geographical barriers. This pathway was described as: 1) being concerned about my sexual health; 2) checking my STI risk easily and privately; 3) understanding and trusting the result; and 4) deciding how to look after my health. Factors that might influence this pathway were also described, including areas for improvement in accessibility and acceptability.

Conclusion

These findings support the role of web-based sexual health applications in facilitating access to sexual health education and behavioural change and underscore the importance of codesign approaches in improving their uptake and impact.

Clinical analysis of severe Chlamydia psittaci pneumonia: Case series study

The clinical characteristics and diagnosis of ten cases with severe Chlamydia psittaci pneumonia were analyzed. Ten patients had high fever, cough, or diarrhea, and all had a history of contact with birds or poultry. The white blood cell count of the patients was normal or slightly increased. The percentage of neutrophils (N%) and C reactive protein of the patients were significantly increased. Chest computer tomography showed patchy consolidation of both lungs, with one-sided lung lobes prominent, and bronchial inflation signs. All the patients were admitted to the intensive care unit due to respiratory failure. Nine patients needed ventilator-assisted ventilation therapy, and one patient needed high-flow oxygen therapy. All patients had sepsis, and five patients developed septic shock. The patients were diagnosed with severe C. psittaci pneumonia by clinical manifestations and contact history. After timely adjustment of tetracycline-based treatment, eight patients recovered and were discharged, and two patients died of septic shock and respiratory failure. Patients with poultry contact should be cautious toward C. psittaci pneumonia. A better method for the detection of C. psittaci is metagenomic next-generation sequencing. Its examination can shorten the diagnosis time. In a later stage, large-sample research is needed to guide clinical diagnosis and treatment.

Crosstalk between the Resident Microbiota and the Immune Cells Regulates Female Genital Tract Health

The female genital tract (FGT) performs several functions related to reproduction, but due to its direct exposure to the external environment, it may suffer microbial infections. Both the upper (uterus and cervix) and lower (vagina) FGT are covered by an epithelium, and contain immune cells (macrophages, dendritic cells, T and B lymphocytes) that afford a robust protection to the host. Its upper and the lower part differ in terms of Lactobacillus spp., which are dominant in the vagina. An alteration of the physiological equilibrium between the local microbiota and immune cells leads to a condition of dysbiosis which, in turn, may account for the outcome of FGT infection. Aerobic vaginitis, bacterial vaginosis, and Chlamydia trachomatis are the most frequent infections, and can lead to severe complications in reproduction and pregnancy. The use of natural products, such as probiotics, polyphenols, and lactoferrin in the course of FGT infections is an issue of current investigation. In spite of positive results, more research is needed to define the most appropriate administration, according to the type of patient.

Histopathological Findings of Ectopic Pregnancy in Contraceptive-Wearing Woman

In normal pregnancy, the egg is fertilized in the fallopian tube. It later moves into the uterus, where it implants into the uterine endometrium. Therefore, implantation of the fertilized egg into the endometrium is not observed in many women using contraceptives. However, if the fallopian tubes are diseased or abnormal, the fertilized egg cannot travel to the endometrium. Thus, the fertilized egg is implanted in tissues other than the uterus, resulting in an ectopic pregnancy. In most cases of ectopic pregnancy, the fertilized egg is implanted into the left or right fallopian tube or in tissues other than the fallopian tubes such as the ovary. With laparoscopic surgery, the scars are small, and the pain and physical burden are also much lesser than those with open surgery; thus, the patient can be rehabilitated immediately. Laparoscopic surgery is preferred for the termination of ectopic pregnancies because the patients recovered quickly physically after surgery and can be discharged in a short period. This paper presents our experience in treating a 37-year-old woman who had a tubal pregnancy despite using a contraceptive. Contrast-enhanced magnetic resonance imaging showed a gestational sac within the right fallopian tube. Laparoscopic surgery was performed to resect the right fallopian tube. Pathological examination suggested that the ectopic pregnancy occurred at the organogenesis stage 9 weeks after fertilization. The pathological findings revealed subpopulations of cells from the ectoderm that were separated from other cells and more specifically formed spinal and ovarian structures. The implantation of the fertilized egg into the endometrium is not observed in many women using contraceptives. However, in rare cases, ectopic pregnancy occurs in women using contraceptives; thus, caution is necessary in diagnosis and treatment. This report presents valuable surgical pathological findings from such a rare case of ectopic pregnancy to understand the differentiation into each tissue during organogenesis.