Point-of-Care Testing for Sexually Transmitted Infections: A Review of Recent Developments

Maternal screening for sexually transmitted infections in pregnant patients in low-resource facilities: A call to action

ASSURED criteria for POC test evaluation and rapid test analysis for STIs are discussed for cost‐effective screening, especially in low‐resource settings. Universal antepartum screening is advocated, with rapid tests as a viable option in low‐resource settings.

Patterns of Use and Barriers to STI Point-of-care Tests for Military Obstetrician Gynecologists

INTRODUCTION

Sexually transmitted infections (STIs) are commonly reported in military populations. Point-of-care tests (POCTs) are commercially available, but their use is variable in the civilian sector. Their use among military providers has not been evaluated. We sought to identify the pattern of use and barriers to using STI POCTs for military obstetrician/gynecologists (OBGYNs).

MATERIALS AND METHODS

We adapted a survey of civilian OBGYNs on patterns of use and barriers to STI POCTs for military OBGYNs. We sent an online questionnaire to 479 military OBGYNs via Army, Air Force, and Navy specialty leaders in May 2023. The questionnaire included 14 demographic questions and up to 52 questions regarding availability, use, and barriers to STI POCTs. The USU Institutional Review Board deemed the study exempt from Institutional Review Board review.

RESULTS

Of the 479 solicited, 117 participated in the survey (24.4%). Of respondents, 64.1% were women and 79.5% non-Hispanic white. Sexually transmitted infections were detected once to twice weekly by 13.0% of respondents and once or twice monthly by 52.8%. The most available STI-related POCTs were wet mount prep (68.7%), rapid HIV (43.3%), and urine dipstick (38.6%). Gram stain was available for 30.3%, the Affirm VPIII (Becton, Dickinson and Company, Franklin Lakes, NJ) for 24.5%, and stat RPR for 16.3%. Economic barriers to using POCTs included cost of the test from manufacturer/distributor (57.9%) and military funding/stocking decisions (10.3%). The greatest barriers to use were the purchasing of an instrument (60.8%) and the interruption to workflow in clinic (57.8%).

CONCLUSIONS

Military OBGYNs rely on several STI-related POCTs. Economic factors and interruption to workflow were cited as the most significant barriers to using POCTs for military OBGYNs. Test cost and impact on workflow should be considered in future development and procurement of POCTs for the Military Health System.

Cost-effectiveness of point-of-care diagnostics for AMR: a systematic review

BACKGROUND

Antimicrobial resistance (AMR) is a major threat to global health. By 2050, it is forecast that AMR will cause 10 million deaths and cost 100 trillion USD annually. Point-of-care tests (POCTs) may represent a cost-effective approach to reduce AMR.

OBJECTIVES

We systematically reviewed which POCTs addressing AMR have undergone economic evaluation in primary and secondary healthcare globally, how these POCTs have been economically evaluated, and which are cost-effective in reducing antimicrobial prescribing or the burden of AMR. Clinical cost-effectiveness was additionally addressed.

METHODS

This systematic review, accordant with PRISMA guidelines, was pre-registered on PROSPERO (CRD42022315192). MEDLINE, PubMed, Embase, Cochrane Library, and Google Scholar were searched from 2000 to 2023 for relevant publications. Quality assessment was performed using the Consensus of Health Economic Criteria.

RESULTS

The search strategy identified 1421 studies, of which 20 met the inclusion criteria. The most common POCTs assessed were for respiratory infections (n = 10), STIs (n = 3), and febrile patients in low- and middle-income countries (n = 3). All studies assessed costs from a healthcare provider perspective; five additionally considered the societal cost of AMR.Eighteen studies identified POCT strategies that reduced antimicrobial prescribing. Of these, 10 identified POCTs that would be considered cost-effective at a willingness-to-pay (WTP) threshold of £33.80 per antibiotic prescription avoided. Most POCT strategies improved clinical outcomes (n = 14); the remainder were clinically neutral.

CONCLUSIONS

There is evidence that some POCTs are cost-effective in reducing antimicrobial prescribing, with potential concomitant clinical benefits. Such interventions-especially CRP POCTs in both high- and low-income settings-merit further, large-scale clinical evaluation.

Relative Cost and Infectious Days Averted Associated With Rapid Gonorrhea and Chlamydia Testing Among Men Who Have Sex With Men

BACKGROUND

Standard-of-care nucleic acid amplification tests (routine NAATs) for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) can take several days to result and therefore delay treatment. Rapid point-of-care GC/CT NAAT (rapid NAAT) could reduce the time to treatment and therefore onward transmission. This study evaluated the incremental cost per infectious day averted and overall cost of implementation associated with rapid compared with routine NAAT.

METHODS

Prospective sexually transmitted infection (STI) treatment data from men who have sex with men and transgender women in San Diego who received rapid NAAT between November 2018 and February 2021 were evaluated. Historical time from testing to treatment for routine NAAT was abstracted from the literature. Costs per test for rapid and routine NAAT were calculated using a micro-costing approach. The incremental cost per infectious day averted comparing rapid to routine NAAT and the costs of rapid GC/CT NAAT implementation in San Diego Public Health STI clinics were calculated.

RESULTS

Overall, 2333 individuals underwent rapid NAAT with a median time from sample collection to treatment of 2 days compared with 7 to 14 days for routine NAAT equating to a reduction of 5 to 12 days. The cost of rapid and routine GC/CT NAAT was $57.86 and $18.38 per test, respectively, with a cost-effectiveness of between $2.43 and $5.82 per infectious day averted. The incremental cost of rapid NAAT improved when at least 2000 tests were performed annually.

CONCLUSIONS

Although rapid GC/CT NAAT is more expensive than routine testing, the reduction of infectious days between testing and treatment may reduce transmission and provide improved STI treatment services to patients.

Asymptomatic infections with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis among women in low- and middle-income countries: A systematic review and meta-analysis

Syndromic management of sexually transmitted infections (STIs) is common in settings with limited access to diagnostic testing. However, this approach does not capture asymptomatic STIs. Untreated asymptomatic infections may result in serious complications and sequelae in women. We aimed to estimate the proportion and the prevalence of asymptomatic Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) infections among women in low- and middle-income countries. We searched Medline, Scopus, and Web of Science for articles published between 2000 and 2022. We used random effect models to compute the proportion and prevalence estimates and performed sub-group analysis. We evaluated the quality of each article using the Appraisal tool for Cross-Sectional Studies and performed sensitivity analyses. This study was registered with PROSPERO, CRD42022286673. Forty-eight eligible studies were included. The proportion of asymptomatic CT, NG, and TV infections were: 60.7% [95% Confidence Interval (CI): 50.4; 70.5], 53.3% [37.1; 69.1], and 56.9% [44.6; 68.9], respectively. The proportion of women with asymptomatic infections was the highest in Africa for the three pathogens. The pooled prevalence of asymptomatic CT, NG, and TV infection was 4.70 per 100 women [95%CI: 3.39; 6.20], 3.11 [1.34; 5.54], and 5.98 [3.46; 9.12], respectively. More than half of the women infected by CT, NG, or TV were asymptomatic. To avoid undiagnosed and untreated asymptomatic infections leading to complications, alternative approaches to syndromic management urgently need to be considered.

Development of a DNA-Based Lateral Flow Strip Membrane Assay for Rapid Screening and Genotyping of Six High-Incidence STD Pathogens

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.

Analysis and mapping of global research publications on point-of-care testing for infectious diseases

RATIONALE

This study presents the first comprehensive analysis and mapping of scientific research on point-of-care testing (POCT) in infectious diseases, filling a gap in understanding the evolving landscape of this field. The identification of research themes and global contributions offers valuable insights.

AIMS AND OBJECTIVES

This manuscript aims to analyse and map scientific research on POCT in the context of infectious diseases.

METHODS

The study employed a comprehensive search strategy using terms related to POCT and infectious diseases. The search was conducted on the Scopus database, refining results based on inclusion and exclusion criteria. The dataset of 1719 research articles was then subjected to descriptive analysis and mapping using VOSviewer.

RESULTS

The research findings indicate an exponential growth in POCT-related publications, with 46.8% published post the COVID-19 pandemic. Plos One journal led in publication frequency, and Biosensors and Bioelectronics received the highest citations per article. North America and Western Europe dominated contributions, with notable participation from China, South Africa, and India. The research landscape revealed the following research themes: detection technologies, human immunodeficiency virus (HIV)/sexually transmitted infection (STI) diagnosis, antibiotic optimisation, and schistosomiasis. Clinical trials focused on antibiotic prescribing, HIV, STIs, and specific infections. The findings suggest a shifting landscape towards POCT, emphasising the need for future planning and investment in healthcare systems. The research identifies areas for future exploration, such as the impact of POCT on antibiotic prescribing and its role in combating infectious diseases in low- and middle-income countries.

CONCLUSION

Implementation of POCT has the potential to revolutionise infectious disease management, improve patient outcomes, and reduce the global burden of diseases. Better public awareness, healthcare team management, and planning for POCT at entry points are crucial for societal benefit. Results demonstrated the evolving role of POCT in infectious disease management and prevention.

Novel point-of-care cytokine biomarker lateral flow test for the screening for sexually transmitted infections and bacterial vaginosis: study protocol of a multicentre multidisciplinary prospective observational clinical study to evaluate the performance and feasibility of the Genital InFlammation Test (GIFT)

INTRODUCTION

A prototype lateral flow device detecting cytokine biomarkers interleukin (IL)-1α and IL-1β has been developed as a point-of-care test-called the Genital InFlammation Test (GIFT)-for detecting genital inflammation associated with sexually transmitted infections (STIs) and/or bacterial vaginosis (BV) in women. In this paper, we describe the rationale and design for studies that will be conducted in South Africa, Zimbabwe and Madagascar to evaluate the performance of GIFT and how it could be integrated into routine care.

METHODS AND ANALYSIS

We will conduct a prospective, multidisciplinary, multicentre, cross-sectional and observational clinical study comprising two distinct components: a biomedical ('diagnostic study') and a qualitative, modelling and economic ('an integration into care study') part. The diagnostic study aims to evaluate GIFT's performance in identifying asymptomatic women with discharge-causing STIs (Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Trichomonas vaginalis (TV) and Mycoplasma genitalium (MG)) and BV. Study participants will be recruited from women attending research sites and family planning services. Several vaginal swabs will be collected for the evaluation of cytokine concentrations (ELISA), STIs (nucleic acid amplification tests), BV (Nugent score) and vaginal microbiome characteristics (16S rRNA gene sequencing). The first collected vaginal swab will be used for the GIFT assay which will be performed in parallel by a healthcare worker in the clinic near the participant, and by a technician in the laboratory. The integration into care study aims to explore how GIFT could be integrated into routine care. Four activities will be conducted: user experiences and/or perceptions of the GIFT device involving qualitative focus group discussions and in-depth interviews with key stakeholders; discrete choice experiments; development of a decision tree classification algorithm; and economic evaluation of defined management algorithms.

ETHICS AND DISSEMINATION

Findings will be reported to participants, collaborators and local government for the three sites, presented at national and international conferences, and disseminated in peer-reviewed publications.The protocol and all study documents such as informed consent forms were reviewed and approved by the University of Cape Town Human Research Ethics Committee (HREC reference 366/2022), Medical Research Council of Zimbabwe (MRCZ/A/2966), Comité d'Ethique pour la Recherche Biomédicale de Madagascar (N° 143 MNSAP/SG/AMM/CERBM) and the London School of Hygiene and Tropical Medicine ethics committee (LSHTM reference 28046).Before the start, this study was submitted to the Clinicaltrials.gov public registry (NCT05723484).

TRIAL REGISTRATION NUMBER

NCT05723484.

Sexually Transmitted Infections in the Emergency Department

As the United States faces a worsening epidemic of sexually transmitted infections (STIs), emergency departments (EDs) play a critical role in identifying and treating these infections. The growing health inequities in the distribution and disproportionate impact of STIs add to the urgency of providing high-quality sexual health care through the ED. Changes in population health are reflected in the new Centers for Disease Control recommendations on screening, diagnostic testing, and treatment of STIs. This review covers common, as well as and less common or emerging STIs, and discusses the state-of-the-art guidance on testing paradigms, extragenital sampling, and antimicrobial treatment and prevention of STIs.

Estimates of the incidence, prevalence, and factors associated with common sexually transmitted infections among Lebanese women

BACKGROUND

We analyzed the prevalence of active infection with common curable sexually transmitted infections (STIs) including N. gonorrhea, C. trachomatis, T. vaginalis, and T. pallidum, as well as active infection with HPV, herpes simplex virus types I (HSV-1) and II (HSV-2), M. hominis, M. genitalium, C. albicans, and Ureaplasma in 351 Lebanese women.

METHODS

A cross-sectional study, involving 351 sexually active women, 40 years or younger, who were recruited from outpatient Obstetrics and Gynecology clinic attendees between September 2016 and November 2017.

RESULTS

The prevalence of active infection was low at 0.3% for N. gonorrhea, 0.6% for HSV-2, 2.8% for C. trachomatis, and 2.9% for any curable STIs. Prevalence of active HPV infection was high assessed at 15.7% for high-risk and 12.2% for low-risk genotypes. Furthermore, the prevalence was 2.0% for M. genitalium, 6.8% for ureaplasma, 13.7% for Candida albicans, and 20.5% for M. hominis. No active infections with T. vaginalis, T. pallidum, or HSV-1 were observed. Significant age differences were noted in the prevalence of high-risk and low-risk HPV genotypes, but no such differences were noted in the prevalence of other infections. No appreciable variations were identified in the prevalence of key STIs based on smoking, marital status, or the number of sexual partners.

CONCLUSIONS

The study documented active infection with substantial prevalence for multiple STIs among women attending outpatient gynecology and obstetrics clinics in Lebanon. These findings underscore the importance of strengthening STI surveillance, linkage to care, and prevention interventions in reducing STI incidence among women.

Implementation of Point of Care Sexually Transmitted Infections Testing in a Community Clinic Setting

ABSTRACT

The rates of sexually transmitted infections (STIs) in the United States, including chlamydia and gonorrhea, are rising. Point-of-care (POC) testing could increase access to testing and treatment. This evaluation found POC STI testing to be concordant with the results of traditional laboratory testing for 100% of patients who were tested. Ninety-five percent of the patients reported being satisfied with the experience, and 66% preferred it to traditional laboratory testing. The most commonly reported reason for preferring the test was the short amount of time it took to receive results. However, insurance reimbursed less than 30% of what was billed for the POC tests. Low insurance reimbursement rates could be a barrier to implementation long-term financial sustainability of POC STI testing.

The cost-effectiveness of syphilis screening in pregnant women: a systematic literature review

Introduction

The cost-effectiveness study of syphilis screening in pregnant women has not been synthesized. This study aimed to synthesize the economic evidence on the cost-effectiveness of syphilis screening in pregnant women that might contribute to making recommendations on the future direction of syphilis screening approaches.

Methods

We systematically searched MEDLINE, PubMed, and Web of Science databases for relevant studies published before 19 January 2023 and identified the cost-effectiveness analyses for syphilis screening in pregnant women. The methodological design quality was appraised by the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 checklist.

Results

In total, 17 literature met the eligibility criteria for a full review. Of the 17 studies, four evaluated interventions using different screening methods, seven assessed a combination of syphilis testing and treatment interventions, three focused on repeat screening intervention, and four evaluated the interventions that integrated syphilis and HIV testing. The most cost-effective strategy appeared to be rapid syphilis testing with high treatment rates in pregnant women who were positive.

Discussion

The cost-effectiveness of syphilis screening for pregnancy has been widely demonstrated. It is very essential to improve the compliance with maternal screening and the treatment rates for positive pregnant women while implementing screening.

Clinical Performance of Cas13a-based Point-of-Care Lateral Flow Assay for Detecting Neisseria gonorrhoeae

Background

Diagnosis of Neisseria (N.) gonorrhoeae is dependent on nucleic acid amplification testing (NAAT), which is not available in resource-limited settings where the prevalence of infection is highest. Recent advances in molecular diagnostics leveraging the high specificity of CRISPR enzymes can permit field-deployable, point-of-care lateral flow assays. We previously reported on the development and in vitro performance of a lateral flow assay for detecting N. gonorrhoeae. Here we aimed to pair that assay with point-of-care DNA extraction techniques and assess the performance on clinical urine specimens.

Methods

We collected an additional urine specimen among individuals enrolling in an ongoing clinical trial at the Massachusetts General Hospital Sexual Health Clinic who presented with symptoms of urethritis or cervicitis (urethral or vaginal discharge, dysuria, or dyspareunia). We then assessed thermal, detergent, and combination DNA extraction conditions, varying the duration of heat at 95°C and concentration of Triton X. We assessed the efficacy of the various DNA extraction methods by quantitative polymerase chain reaction (qPCR). Once an extraction method was selected, we incubated samples for 90 minutes to permit isothermal recombinase polymerase amplification. We then assessed the performance of lateral flow Cas13a-based detection using our previously designed porA probe and primer system for N. gonorrhoeae detection, comparing lateral flow results with NAAT results from clinical care.

Results

We assessed DNA extraction conditions on 3 clinical urine specimens. There was no consistent significant difference in copies per microliter of DNA obtained using more or less heat. On average, we noted that 0.02% triton combined with 5 minutes of heating to 95°C resulted in the highest DNA yield, however, 0.02% triton alone resulted in a quantity of DNA that was above the previously determined analytic sensitivity of the assay. Given that detergent-based extraction is more easily deployable, we selected that as our method for extraction. We treated 23 clinical specimens with 0.02% triton, which we added to the Cas13a detection system. We ran all lateral flow detections in duplicate. The Cas13a-based assay detected 8 of 8 (100%) positive specimens, and 0 of 15 negative specimens.

Conclusion

Using point-of-care DNA extraction, isothermal amplification, and Cas13a-based detection, our point-of-care lateral flow N. gonorrhoeae assay correctly identified 23 clinical urine specimens as either positive or negative. Further evaluation of this assay among larger samples and more diverse sample types is warranted.

Self-reported uptake of STI testing services among adolescents and young people aged 15-24 years: Findings from the Yathu Yathu cluster randomized trial in Lusaka, Zambia

There is little evidence regarding community-based delivery of STI testing and treatment for youth aged 15-24 (AYP) in Zambia. In a cluster-randomised trial, we evaluated whether offering syndromic STI screening through community-based, peer-led sexual and reproductive health services (Yathu Yathu) with referral to a local health facility for testing, increased self-reported testing for STIs (other than HIV) among AYP. Two communities in Lusaka were divided into 10 zones each (20 zones in total); by community, zones were randomly allocated (1:1) to Yathu Yathu or control. Monitoring data were used to describe syndromic STI screening through Yathu Yathu and an endline cross-sectional survey used to evaluate the impact of Yathu Yathu on self-reported ever and recent (last 12 months) STI testing. 10,974 AYP accessed Yathu Yathu; 66.6% (females-67.7%; males-64.7%) were screened for STIs, 6.2% reported any STI symptoms. In the endline survey, 23.3% (n = 350/1501) of AYP who ever had sex ever STI tested; 13.5% (n = 174/1498) who had sex in the last 12 months recently STI tested. By trial arm, there was no difference in self-reported ever or recent STI testing among all AYP. Among men aged 20-24, there was evidence that ever STI testing was higher in the Yathu Yathu compared to control arm (24.1% vs 16.1%; adjPR = 1.67 95%CI = 1.02, 2.74; p = 0.04). Among AYP who ever STI tested, 6.6% (n = 23) reported ever being diagnosed with an STI. Syndromic STI management through community-based, peer-led services showed no impact on self-reported STI testing among AYP. Research on community-based delivery of (near) point-of-care diagnostics is needed. Trial registration number(s): NCT04060420 https://clinicaltrials.gov/ct2/show/NCT04060420; and ISRCTN75609016; https://doi.org/10.1186/ISRCTN75609016.

On The Horizon: Novel Approaches to Sexually Transmitted Infection Prevention

Rates of sexually transmitted infections (STIs), especially cases of infectious and congenital syphilis, are increasing in the United States. Novel strategies for STI prevention are being explored and include doxycycline post-exposure prophylaxis and the potential utility of vaccines against gonorrhea. Self-collection of samples and point of care testing for STI are increasingly being employed in a variety of settings. Both can improve uptake of screening and lead to earlier detection and treatment of incident STI in target populations. Overcoming existing regulatory issues and optimizing implementation of current evidence-based strategies will be key to maximizing future STI prevention efforts. Here we provide an update for primary care providers on selected new strategies for STI prevention either currently available or under development for possible future use.

Independent clinic-based evaluation of dual POCTs for screening for HIV and syphilis in men who have sex with men in Italy, Malta, Peru, and the United Kingdom

INTRODUCTION

Globally, the incidence of HIV and syphilis can be reduced by the use of validated point of care tests (POCTs). As part of the WHO PRoSPeRo Network, we aimed to evaluate the performance, acceptability, and operational characteristics of two dual HIV/syphilis POCTs (Bioline HIV/Syphilis Duo (Abbott) and DPP® HIV-Syphilis assay (Chembio) for the screening of HIV and syphilis amongst men who have sex with men (MSM).

METHOD AND ANALYSES

A cross sectional study of 2,577 MSM in Italy, Malta, Peru, and the United Kingdom (UK) presenting to seven clinic sites, were enrolled. Finger prick blood was collected to perform POCTs and results compared with standard laboratory investigations on venepuncture blood. Acceptability and operational characteristics were assessed using questionnaires. Diagnostic meta-analysis was used to combine data from the evaluation sites.

RESULTS

Based on laboratory tests, 23.46% (n = 598/2549) of participants were confirmed HIV positive, and 35.88% of participants (n = 901/2511) were positive on treponemal reference testing. Of all participants showing evidence of antibodies to Treponema pallidum, 50.56% (n = 455/900) were Rapid Plasma Reagin (RPR) test reactive. Of HIV positive individuals, 60.62% (n = 354/584) had evidence of antibodies to T. pallidum, and of these 60.45% (n = 214/354) exhibited reactive RPR tests indicating probable (co)infection. For Bioline POCT, pooled sensitivities and specificities for HIV were 98.95% and 99.89% respectively, and for syphilis were 73.79% and 99.57%. For Chembio pooled sensitivities and specificities for HIV were 98.66% and 99.55%, and for syphilis were 78.60% and 99.48%. Both tests can detect greater than 90% of probable active syphilis cases, as defined by reactive RPR and treponemal test results. These dual POCTs were preferred by 74.77% (n = 1,926) of participants, due to their convenience, and the operational characteristics made them acceptable to health care providers (HCPs).

CONCLUSIONS

Both the Bioline and the Chembio dual POCT for syphilis and HIV had acceptable performance, acceptability and operational characteristics amongst MSM in the PRoSPeRo network. These dual POCTs could serve as a strategic, more cost effective, patient and healthcare provider (HCP) friendly alternative to conventional testing; in clinical and other field settings, especially those in resource-limited settings.

Microfluidic systems for infectious disease diagnostics

Microorganisms, encompassing both uni- and multicellular entities, exhibit remarkable diversity as omnipresent life forms in nature. They play a pivotal role by supplying essential components for sustaining biological processes across diverse ecosystems, including higher host organisms. The complex interactions within the human gut microbiota are crucial for metabolic functions, immune responses, and biochemical signalling, particularly through the gut-brain axis. Viruses also play important roles in biological processes, for example by increasing genetic diversity through horizontal gene transfer when replicating inside living cells. On the other hand, infection of the human body by microbiological agents may lead to severe physiological disorders and diseases. Infectious diseases pose a significant burden on global healthcare systems, characterized by substantial variations in the epidemiological landscape. Fast spreading antibiotic resistance or uncontrolled outbreaks of communicable diseases are major challenges at present. Furthermore, delivering field-proven point-of-care diagnostic tools to the most severely affected populations in low-resource settings is particularly important and challenging. New paradigms and technological approaches enabling rapid and informed disease management need to be implemented. In this respect, infectious disease diagnostics taking advantage of microfluidic systems combined with integrated biosensor-based pathogen detection offers a host of innovative and promising solutions. In this review, we aim to outline recent activities and progress in the development of microfluidic diagnostic tools. Our literature research mainly covers the last 5 years. We will follow a classification scheme based on the human body systems primarily involved at the clinical level or on specific pathogen transmission modes. Important diseases, such as tuberculosis and malaria, will be addressed more extensively.

The Past, Present, and Future in the Diagnosis of a Neglected Sexually Transmitted Infection: Trichomoniasis

More than one million curable sexually transmitted infections occur every day. Trichomonas vaginalis is one of the main infections responsible for these epidemiological data; however, the diagnosis of this protozoan is still mainly based on microscopic and culture identification. The commercialization of immunological tests and the development of molecular techniques have improved the sensitivity of classical methods. Nevertheless, the fact that trichomoniasis is a neglected parasitic infection hinders the development of novel techniques and their implementation in routine diagnosis. This review article shows the different methods developed to identify T. vaginalis in population and the difficulties in diagnosing male and asymptomatic patients. The importance of including this parasite in routine gynecological screening, especially in pregnant women, and the importance of considering T. vaginalis as an indicator of high-risk sexual behavior are also discussed.

Access to HIV/STI testing among male and female Venezuelan migrants in Peru: evidence from a nationwide survey

BACKGROUND

Human immunodeficiency virus (HIV) infection and sexually transmitted infections (STIs) are major global public health issues. Migrants represent a vulnerable group that faces multiple barriers to access to healthcare services, including HIV/STI testing. This study aimed to assess the factors associated with access to HIV/STI testing in male and female Venezuelan migrants in Peru.

METHODS

This was a cross-sectional study involving secondary data analysis of the 2022 Venezuelan Population Residing in Peru Survey. The study was conducted in the eight most populated cities inhabited by Venezuelan migrants and refugees. For each city, the sampling design was probabilistic, stratified, and independent. The outcome variable was whether participants had access to HIV or other STI testing during their stay in Peru. Statistical analysis was stratified by sex owing to potential effect modification. Crude and adjusted prevalence ratios were calculated using generalized linear models Poisson family with log link function. Confidence intervals were calculated to 95%.

RESULTS

A total of 3,723 male and 3,984 female migrants were included. Access to HIV/STI testing among male and female migrants was 19.85% and 25.16%, respectively. Among male migrants, being LGBTI, health insured, and married or cohabiting were associated with increased access to HIV/STI testing. Among females, those aged 18-44 years, those who were married or cohabiting and were health insured, and those residing for more than 1 year in Peru were significantly more likely to have access to HIV/STI testing. Moreover, physical/mental disability and unemployed status were associated with a lower probability of HIV/STI testing in females.

CONCLUSIONS

Only two in ten Venezuelan migrants and refugees in Peru were screened for HIV/STI, with fewer males than females. Sex-specific sociodemographic, health-related, and migration-related variables were independently associated with access to HIV/STI testing.

Anorectal gonorrhoea and chlamydia among transgender women in Brazil: prevalence and assessment of performance and cost of anorectal infection detection and management approaches

OBJECTIVES

We aimed to determine the prevalence of anorectal Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) among transgender women in Brazil, and to assess the performance and costs of various approaches for the diagnosis and management of anorectal NG/CT.

METHODS

TransOdara was a multicentric, cross-sectional STI prevalence study among 1317 transgender women conducted in five capital cities representing all Brazilian regions. Participants aged >18 years were recruited using respondent-driven sampling (RDS), completed an interviewer-led questionnaire, offered an optional physical examination and given choice between self-collected or provider-collected samples for NG/CT testing. Performance and cost indicators of predetermined management algorithms based on the WHO recommendations for anorectal symptoms were calculated.

RESULTS

Screening uptake was high (94.3%) and the estimated prevalence of anorectal NG, CT and NG and/or CT was 9.1%, 8.9% and 15.2%, respectively. Most detected anorectal NG/CT infections were asymptomatic (NG: 87.6%, CT: 88.9%), with a limited number of participants reporting any anorectal symptoms (9.1%). Of those who permitted anal examination, few had clinical signs of infection (13.6%). Sensitivity of the tested algorithms ranged from 1.4% to 5.1% (highest for treatment based on the reported anorectal discharge or ulcer and receptive anal intercourse (RAI) in the past 6 months) and specificity from 98.0% to 99.3% (highest for treatment based on the reported anorectal discharge with clinical confirmation or report of RAI). The estimated cost-per-true case of anorectal NG/CT infection treated varied from lowest providing treatment for anorectal discharge syndrome based on the reported RAI ($2.70-4.28), with algorithms including clinical examinations decreasing cost-effectiveness.

CONCLUSIONS

High prevalence of mostly asymptomatic anorectal NG and CT was observed among Brazilian transgender women. Multi-site NG/CT screening should be offered to transgender women. Where diagnostic testing capacity is limited, syndromic management for those presenting with anorectal symptoms is recommended.

Cyr SB, Rönn MM, Salomon JA, Grad YH. The Impact of Rapid Drug Susceptibility Tests on Gonorrhea Burden and the Life Span of Antibiotic Treatments: A Modeling Study Among Men Who Have Sex With Men in the United States

Rapid point-of-care tests that diagnose gonococcal infections and identify susceptibility to antibiotics enable individualized treatment. This could improve patient outcomes and slow the emergence and spread of antibiotic resistance. However, little is known about the long-term impact of such diagnostics on the burden of gonorrhea and the effective life span of antibiotics. We used a mathematical model of gonorrhea transmission among men who have sex with men in the United States to project the annual rate of reported gonorrhea cases and the effective life span of ceftriaxone, the recommended antibiotic for first-line treatment of gonorrhea, as well as 2 previously recommended antibiotics, ciprofloxacin and tetracycline, when a rapid drug susceptibility test that estimates susceptibility to ciprofloxacin and tetracycline is available. The use of a rapid drug susceptibility test with ≥50% sensitivity and ≥95% specificity, defined in terms of correct ascertainment of drug susceptibility and nonsusceptibility status, could increase the combined effective life span of ciprofloxacin, tetracycline, and ceftriaxone by at least 2 years over 25 years of simulation. If test specificity is imperfect, however, the increase in the effective life span of antibiotics is accompanied by an increase in the rate of reported gonorrhea cases even under perfect sensitivity.

On-site testing and treatment of sexually transmitted infections among female sex workers using molecular point-of-care testing integrated into harm reduction services in Madrid, Spain

INTRODUCTION

This study aimed to evaluate the feasibility of molecular point-of-care testing for STIs, the prevalence of STIs and associated factors, and testing and treatment uptake among street-based female sex workers (FSWs) attending a mobile harm reduction unit in Madrid, Spain.

METHODS

This was a prospective, longitudinal study. From August 15th to December 6th, 2022, participants were screened for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis using molecular testing (Xpert) on self-collected urine samples at a mobile harm reduction unit. Additionally, rapid tests were used to screen participants for HIV, hepatitis C virus (HCV), and syphilis. On-site same-day results and treatment for those infected were offered.

RESULTS

Among 77 FSWs included the median age was 40 (range, 33-48), 64 % were homeless, and 84 % reported drug use in the past six months. Four participants self-reported having HIV, of whom all were on antiretroviral therapy, and 14 (18 %) had HCV antibodies, including three with current infection. The prevalence of at least one STI was 66 %. When categorized by type of STI, the prevalences were as follows: 15 % for CT, 15 % for NG, 51 % for TV, and 21 % for syphilis. Notably, the prevalence of STIs was higher among FSW with recent drug use, with no cases of CT or NG detected among FSWs who did not recently use drugs. In adjusted analysis, drug use was associated an increased odds of having an STI (adjusted odds ratio, 10.47; 95 % CI: 1.67-65.42). All participants consented to screening, and all but one received on-site result-based linkage to treatment.

CONCLUSIONS

This study demonstrates the feasibility, high STI prevalence, and high linkage to testing and treatment following point-of-care molecular testing among street-based FSWs who have recently used drugs in Madrid, Spain.

Evaluating the effect of the plan of national syphilis control in controlling the syphilis epidemic in Jiangsu, China 2010-2020

Background

Starting in 2010, the Chinese government initiated a 10-year syphilis control plan, called the national syphilis control plan (NSCP), to address the emerging threat of syphilis. We aimed to evaluate the effect of the NSCP plan on syphilis control in Jiangsu, China.

Methods

The temporal trends of syphilis incidence, prevalence and rate of condom use were estimated by Joinpoint regression with average annual percent change (APC) and average annual percentage (APPC). A Chi-square test was conducted to analyze the outcomes in different subgroups. ArcGIS was used to analyze the spatiotemporal distribution of syphilis incidence.

Results

Geographically, early and congenital syphilis incidence decreased significantly in all areas of the province during the period of NSCP. Early syphilis incidence decreased from 21.1 to 8.8 (APC: -7.5, 95%CI: -8.6, -6.5, p < 0.001) per 100,000 people, and congenital syphilis decreased from 63.6 to 4.1 (APC: -14.8, 95%CI: -20.8, -8.4, p < 0.01) per 100,000 newborns from 2010 to 2020. Also, syphilis prevalence reduced from 13.4 to 3.8% (APC: -8.7, 95%CI: -12.1, -5.0, p = 0.001) among men who have sex with men, from 5.3 to 1.7% (APC: -7.9, 95%CI: -11.7, -3.8, p = 0.002) among female sex workers and remained under 1.0% with slight variations among pregnant women (APC: 0.3, 95%CI: -4.3, 5.1, p = 0.877) from 2010 to 2020. 0.2% (2,436) of pregnant women who received free syphilis testing during pregnancy were diagnosed with current syphilis infection, and 97.0% (2,555) of newborns in the province were delivered to women diagnosed with syphilis. 91.8% (2,346) of live babies and about 90% of diagnosed patients received complete standard syphilis diagnosis and treatment services.

Conclusion

Trends of early syphilis incidence and syphilis prevalence show a considerable decreasing trend among almost all the key populations after implementing NSCP. Congenital syphilis has significantly decreased as well and hence, the NSCP program should be sustained and strengthened to control the syphilis epidemic in China further.

Highly-Specific Single-Stranded Oligonucleotides and Functional Nanoprobes for Clinical Determination of Chlamydia Trachomatis and Neisseria Gonorrhoeae Infections

Early detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) is the key to controlling the spread of these bacterial infections. An important step in developing biosensors involves identifying reliable sensing probes against specific genetic targets for CT and NG. Here, the authors have designed single-stranded oligonucleotides (ssDNAs) targeting mutually conserved genetic regions of cryptic plasmid and chromosomal DNA of both CT and NG. The 5'- and 3'- ends of these ssDNAs are differentially functionalized with thiol groups and coupled with gold nanoparticles (AuNP) to develop absorbance-based assay. The AuNPs agglomerate selectively in the presence of its target DNA sequence and demonstrate a change in their surface plasmon resonance. The optimized assay is then used to detect both CT and NG DNA extracted from 60 anonymized clinical samples with a clinical sensitivity of ∼100%. The limit of detection of the assays are found to be 7 and 5 copies/µL for CT and NG respectively. Furthermore, it can successfully detect the DNA levels of these two bacteria without the need for DNA extraction and via a lateral flow-based platform. These assays thus hold the potential to be employed in clinics for rapid and efficient monitoring of sexually transmitted infections.

Selection of DNA Aptamers Against Neisseria gonorrhoeae Causing Sexually Transmitted Infection (STI)

Neisseria gonorrhoeae (NG) is the second most common bacterial sexually transmitted infection (STI) worldwide. Gonorrhoea is a very serious infection because if untreated, it can lead to significant ramifications to reproductive, maternal, & newborn health and increase transmission of HIV. Infections are very often asymptomatic and symptoms when present manifest differently in men and women. The cornerstone of gonorrhoea control is to assure rapid diagnosis and prompt treatment of patients to prevent the onward spread of infection. The resource-rich settings are utilizing nucleic acid amplification tests (NAATs) for diagnosis, whereas resource-limited settings like ours where laboratory infrastructure is lacking, reliance is placed on syndromic approach. In view of the limitations of each, there is a compelling need for development of a point of care test (POCT). Aptamers offer such potential. These are short oligonucleotides that bind to its target with high affinity and specificity and therefore can be maneuvred for use in diagnostics. In this study, we performed live cell-SELEX (Systematic Evolution of Ligands by EXponential enrichment) to select 12 single-stranded DNA (ssDNA) aptamers that bind strongly to a cocktail of Neisseria gonorrhoeae strains, with Kd values ranging from 8.58 to 596 nM. Gold nanoparticle (GNP) assay revealed that one of the aptamers, E8 19 was highly specific for Neisseria gonorrhoeae (Kd = 24.5 nM). More importantly, it did not demonstrate any binding to Neisseria meningitidis and commensal Neisseria sp. The identified aptamer holds much promise for the development of a rapid test for diagnosis of gonorrhoea.

Molecular point-of-care devices for the diagnosis of infectious diseases in resource-limited settings - A review of the current landscape, technical challenges, and clinical impact

Molecular point-of-care (POC) tests offer high sensitivity, rapid turnaround times, relative ease of use, and the convenience of laboratory-grade testing in the absence of formal laboratory spaces and equipment, making them appealing options for infectious disease diagnosis in resource-limited settings. In this review, we discuss the role and potential of molecular POC tests in resource-limited settings and their associated logistical challenges. We discuss U.S. Food and Drug Administration approval, Clinical Laboratory Improvement Amendments complexity levels, and the REASSURED criteria as a starting point for assessing options currently available inside and outside of the United States. We then present POC tests currently in research and development phases that have potential for commercialization and implementation in limited-resource settings. Finally, we review published studies that have assessed the clinical impact of molecular POC testing in limited- and moderate-resource settings.

Awareness of Heightened Sexual and Behavioral Vulnerability as a Trigger for PrEP Resumption Among Adolescent Girls and Young Women in East and Southern Africa

PURPOSE OF REVIEW

East and Southern Africa are the epicenter of the HIV epidemic. High HIV incidence rates among adolescent girls and young women (AGYW) remain stable over the last decade despite access to daily oral PrEP. Some settings have experienced high PrEP uptake among AGYW; however, discontinuation has been high. This review sought to understand drivers of PrEP discontinuation in this population in order to identify potential mechanisms to facilitate PrEP restart and optimize PrEP use.

RECENT FINDINGS

Drivers of PrEP discontinuation included low perceived HIV acquisition risk, PrEP-associated side effects, pill burden, family/sexual partner disapproval, lack of/intermittent sexual activity, PrEP use stigma, fear of intimate partner violence, misinformation about long-term PrEP use, and limited/inconsistent access to PrEP. The most frequently reported driver of PrEP discontinuation was low perceived HIV acquisition risk. This indicates that innovative interventions to help AGYW recognize their HIV risk and make informed decisions about PrEP use are urgently needed.

Potential delayed and/or missed STI diagnoses among outpatients presenting with lower genitourinary tract symptoms: a real-world database study

OBJECTIVES

Sexually transmitted infection (STI) diagnosis is complicated as these infections can present with lower genitourinary tract symptoms (LGUTS) that overlap with other disorders, i.e. urinary tract infections (UTIs). The study's objective was to determine potential missed STI diagnoses from patients presenting with LGUTS in the US between January 2010 and December 2019.

METHODS

The de-identified insurance claims data from the IBM® MarketScan® Research Databases were collected from patients (14-64 years old) who presented with LGUTS, which could be caused by an STI. A 'GAP' cohort was created, consisting of episodes with potentially delayed STI (Chlamydia trachomatis [CT]/Neisseria gonorrhoeae [NG]) treatment. The intention was to capture episodes where an STI was not initially suspected. Four subgroups were defined depending on the treatment received (fluoroquinolone; azithromycin and/or doxycycline; cephalosporins; gentamicin and azithromycin).

RESULTS

The GAP cohort consisted of 833,574 LGUTS episodes from the original cohort (23,537,812 episodes). Post-index CT/NG testing was carried out for 4.6% and 5.4% of the episodes from men and women, respectively. There were ≥2 return visits for 16.1% and 15.8% of the episodes from men and women, respectively. A substantial percentage of episodes from men (52.1%) and women (68.3%) were diagnosed with a UTI and/or acute cystitis at the index prior to receiving post-index STI treatment. Other top conditions diagnosed at index for men were dysuria (25.8% of the episodes), orchitis/epididymitis (14.3% of the episodes), and acute prostatitis (10.1% of the episodes), and for women were dysuria (24.2% of the episodes), vaginitis/vulvitis/vulvovaginitis (11.7% of the episodes), and cervicitis (3.3% of the episodes).

CONCLUSION

These findings highlight delayed STI antibiotic treatment and low rates of CT/NG testing, suggesting late STI consideration and suboptimal diagnosis. Additionally, our study illustrates the importance of accurately diagnosing and treating STIs in patients with LGUTS and associated conditions, to avoid antibiotic misuse and complications from delayed administration of appropriate treatment.

Development of Cas13a-based assays for Neisseria gonorrhoeae detection and gyrase A determination

Neisseria gonorrhoeae is one of the most common bacterial sexually transmitted infections. The emergence of antimicrobial-resistant N. gonorrhoeae is an urgent public health threat. Currently, the diagnosis of N. gonorrhoeae infection requires expensive laboratory infrastructure, while antimicrobial susceptibility determination requires bacterial culture, both of which are infeasible in low-resource areas where the prevalence of infection is highest. Recent advances in molecular diagnostics, such as specific high-sensitivity enzymatic reporter unlocking (SHERLOCK) using CRISPR-Cas13a and isothermal amplification, have the potential to provide low-cost detection of pathogen and antimicrobial resistance. We designed and optimized RNA guides and primer sets for SHERLOCK assays capable of detecting N. gonorrhoeae via the porA gene and of predicting ciprofloxacin susceptibility via a single mutation in the gyrase A (gyrA) gene. We evaluated their performance using both synthetic DNA and purified N. gonorrhoeae isolates. For porA, we created both a fluorescence-based assay and lateral flow assay using a biotinylated fluorescein reporter. Both methods demonstrated sensitive detection of 14 N. gonorrhoeae isolates and no cross-reactivity with 3 non-gonococcal Neisseria isolates. For gyrA, we created a fluorescence-based assay that correctly distinguished between 20 purified N. gonorrhoeae isolates with phenotypic ciprofloxacin resistance and 3 with phenotypic susceptibility. We confirmed the gyrA genotype predictions from the fluorescence-based assay with DNA sequencing, which showed 100% concordance for the isolates studied. We report the development of Cas13a-based SHERLOCK assays that detect N. gonorrhoeae and differentiate ciprofloxacin-resistant isolates from ciprofloxacin-susceptible isolates. IMPORTANCE Neisseria gonorrhoeae, the cause of gonorrhea, disproportionately affects resource-limited settings. Such areas, however, lack the technical capabilities for diagnosing the infection. The consequences of poor or absent diagnostics include increased disease morbidity, which, for gonorrhea, includes an increased risk for HIV infection, infertility, and neonatal blindness, as well as an overuse of antibiotics that contributes to the emergence of antibiotic resistance. We used a novel CRISPR-based technology to develop a rapid test that does not require laboratory infrastructure for both diagnosing gonorrhea and predicting whether ciprofloxacin can be used in its treatment, a one-time oral pill. With further development, that diagnostic test may be of use in low-resource settings.

The Interventions and Challenges of Antimicrobial Stewardship in the Emergency Department

Over the last decades, we have witnessed a constant increase in infections caused by multi-drug-resistant strains in emergency departments. Despite the demonstrated effectiveness of antimicrobial stewardship programs in antibiotic consumption and minimizing multi-drug-resistant bacterium development, the characteristics of emergency departments pose a challenge to their implementation. The inclusion of rapid diagnostic tests, tracking microbiological results upon discharge, conducting audits with feedback, and implementing multimodal educational interventions have proven to be effective tools for optimizing antibiotic use in these units. Nevertheless, future multicenter studies are essential to determine the best way to proceed and measure outcomes in this scenario.

Sexually transmitted infections in Spain: Current status

Sexually Transmitted Infections (STI) are a major public health problem. The problems inherent to their diagnosis, treatment and prevention have to do not only with their nature, but also with organizational issues and overlapping competencies of the different health authorities in Spain. The real situation of STI in Spain, at present, is poorly known. For this reason, the Scientific Committee on COVID and Emerging Pathogens of the Illustrious Official College of Physicians of Madrid (ICOMEM) has formulated a series of questions on this subject which were distributed, not only among the members of the Committee, but also among experts outside it. The central health authorities provide very high and increasing figures for gonococcal infection, syphilis, Chlamydia trachomatis infection and lymphogranuloma venereum (LGV). Both HIV infection and Monkeypox are two important STI caused by viruses in our environment, to which it should be added, mainly, Herpes simplex virus (HSV) and Human papillomavirus (HPV) infections. Emerging microorganisms such as Mycoplasma genitalium pose not only pathogenic challenges but also therapeutic problems, as in the case of N. gonohrroeae. The pathways that patients with suspected STI follow until they are adequately diagnosed and treated are not well known in Spain. Experts understand that this problem is fundamentally managed in public health institutions, and that Primary Care and Hospital Emergency Services, together with some institutions that deal monographically with this problem, are the recipients of most of these patients. One of the most serious difficulties of STI lies in the availability of the microbiological tests necessary for their diagnosis, particularly in this era of outsourcing of microbiology services. Added to this is the increased cost of implementing the latest generation of molecular techniques and the difficulties of transporting samples. It is clear that STI are not diseases to which the entire population is equally exposed and it is necessary to have a better knowledge of the risk groups where to focus the necessary interventions adapted to their characteristics. It should not be forgotten that STI are also a problem in the pediatric age group and that their presence can be a marker of sexual abuse with all that this implies in terms of health care and medicolegal activity. Finally, STI are infections that are associated with a high cost of care for which we have very little information. The possibility of expanding the automatic performance of laboratory tests for STI surveillance through laboratory routines is encountering ethical and legal problems that are not always easy to solve. Spain has created a ministerial area of specific attention to STI and there are plans to improve the diagnosis, treatment and prevention of these problems, but we still lack the necessary evidence on their impact. We cannot forget that these are diseases that transcend the individual and constitute a Public Health problem.

Self-sampling strategies (with/without digital innovations) in populations at risk of Chlamydia trachomatis and Neisseria gonorrhoeae: a systematic review and meta-analyses

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) resulted in over 200 million new sexually transmitted infections last year. Self-sampling strategies alone or combined with digital innovations (ie, online, mobile or computing technologies supporting self-sampling) could improve screening methods. Evidence on all outcomes has not yet been synthesised, so we conducted a systematic review and meta-analysis to address this limitation.

METHODS

We searched three databases (period: 1 January 2000-6 January 2023) for reports on self-sampling for CT/GC testing. Outcomes considered for inclusion were: accuracy, feasibility, patient-centred and impact (ie, changes in linkage to care, first-time testers, uptake, turnaround time or referrals attributable to self-sampling).We used bivariate regression models to meta-analyse accuracy measures from self-sampled CT/GC tests and obtain pooled sensitivity/specificity estimates. We assessed quality with Cochrane Risk of Bias Tool-2, Newcastle-Ottawa Scale and Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

We summarised results from 45 studies reporting self-sampling alone (73.3%; 33 of 45) or combined with digital innovations (26.7%; 12 of 45) conducted in 10 high-income (HICs; n=34) and 8 low/middle-income countries (LMICs; n=11). 95.6% (43 of 45) were observational, while 4.4% (2 of 45) were randomised clinical trials.We noted that pooled sensitivity (n=13) for CT/GC was higher in extragenital self-sampling (>91.6% (86.0%-95.1%)) than in vaginal self-sampling (79.6% (62.1%-90.3%)), while pooled specificity remained high (>99.0% (98.2%-99.5%)).Participants found self-sampling highly acceptable (80.0%-100.0%; n=24), but preference varied (23.1%-83.0%; n=16).Self-sampling reached 51.0%-70.0% (n=3) of first-time testers and resulted in 89.0%-100.0% (n=3) linkages to care. Digital innovations led to 65.0%-92% engagement and 43.8%-57.1% kit return rates (n=3).Quality of studies varied.

DISCUSSION

Self-sampling had mixed sensitivity, reached first-time testers and was accepted with high linkages to care. We recommend self-sampling for CT/GC in HICs but additional evaluations in LMICs. Digital innovations impacted engagement and may reduce disease burden in hard-to-reach populations.

PROSPERO REGISTRATION NUMBER

CRD42021262950.

Inadequate performance of a risk score to predict asymptomatic Neisseria gonorrhoeae and Chlamydia trachomatis infection among cisgender men who have sex with men

OBJECTIVES

Epidemiological treatment of persons who are sexual contacts to partners with Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) often results in treatment of uninfected persons, which may increase the risk of antibiotic-resistant infections. We sought to identify the predictors of NG and/or CT infections to develop a risk score that could be used to limit epidemiological treatment to persons most likely to have these infections.

METHODS

We included visits to the Public Health - Seattle & King County Sexual Health Clinic by asymptomatic cisgender men who have sex with men (MSM) aged ≥18 who presented as a sexual contact to partner(s) with CT or NG infection between 2011 and 2019. We used logistic regression to estimate the odds of CT and/or NG infections associated with demographic and clinical predictors, selecting the final set of predictors using the Akaike information criteria and obtaining score weights from model coefficients. We used a cross-validation approach to obtain average model discrimination from each of 10 models, leaving out 10% of the data, and evaluated sensitivity and specificity at various score cut-offs.

RESULTS

The final model for predicting NG or CT infection included seven predictors (age <35 years, HIV status, receptive oral sex in the prior 2 months, CT diagnosis, condomless receptive anal intercourse, condomless insertive anal intercourse and methamphetamine use in the prior 12 months). Model discrimination, as measured by the receiver operating curve, was 0.60 (95% CI 0.54 to 0.66). Sensitivity for detection of infection was ≥90% for scores ≥3, ≥5 and ≥7; specificity for these cut-offs was <16%. At scores ≥9, ≥12 and ≥14, specificity increased but sensitivity decreased to ≤76%.

CONCLUSIONS

Our risk score did not sufficiently discriminate between asymptomatic MSM with and without NG/CT infection. Additional studies evaluating epidemiological treatment as a standard of care in diverse populations are needed to guide best practices in the management of contacts to NG/CT infection.

A comprehensive review for machine learning based human papillomavirus detection in forensic identification with multiple medical samples

Human papillomavirus (HPV) is a sexually transmitted virus. Cervical cancer is one of the highest incidences of cancer, almost all patients are accompanied by HPV infection. In addition, the occurrence of a variety of cancers is also associated with HPV infection. HPV vaccination has gained widespread popularity in recent years with the increase in public health awareness. In this context, HPV testing not only needs to be sensitive and specific but also needs to trace the source of HPV infection. Through machine learning and deep learning, information from medical examinations can be used more effectively. In this review, we discuss recent advances in HPV testing in combination with machine learning and deep learning.

Outpatient sexually transmitted infection testing and treatment patterns in the United States: a real-world database study

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are the most common notifiable sexually transmitted infections (STIs) in the United States. Because symptoms of these infections often overlap with other urogenital infections, misdiagnosis and incorrect treatment can occur unless appropriate STI diagnostic testing is performed in clinical settings. The objective of this study was to describe STI diagnostic testing and antimicrobial treatment patterns and trends among adolescent and adult men and women with lower genitourinary tract symptoms (LGUTS).

METHODS

We analyzed insurance claims data from the IBM® MarketScan® Research Databases. Patients included were between 14 and 64 years old with LGUTS as determined by selected International Classification of Diseases codes between January 2010 and December 2019. Testing of STIs and relevant drug claims were captured, and distribution of testing patterns and drug claims were described.

RESULTS

In total, 23,537,812 episodes with LGUTS (87.4% from women; 12.6% from men) were analyzed from 12,341,154 patients. CT/NG testing occurred in only 17.6% of all episodes. For episodes where patients received treatment within 2 weeks of the visit date, 89.3% received treatment within the first 3 days (likely indicating presumptive treatment), and 77.7% received it on the first day. For women with pelvic inflammatory disease and men with orchitis/epididymitis and acute prostatitis, ≤ 15% received CT/NG testing, and around one-half received antibiotic treatment within 3 days.

CONCLUSIONS

Our study revealed low CT/NG testing rates, even in patients diagnosed with complications commonly associated with these STIs, along with high levels of potentially inappropriate presumptive treatment. This highlights the need for timely and accurate STI diagnosis in patients with LGUTS to inform appropriate treatment recommendations.

Point-of-Care Testing for Sexually Transmitted Infections

Point-of-care testing for sexually transmitted infections is essential for controlling transmission and preventing sequelae in high-risk populations. Since the World Health Organization published the ASSURED criteria, point-of-care testing has improved for use in large population screening and rapid testing that prevents loss of clinical follow-up. Recent advancements have been advantageous for low-resource areas allowing testing at a minimal cost without reliable electricity or refrigeration. Point-of-care nucleic acid detection and amplification techniques are recommended, but are often inaccessible in low-resource areas. Future advancements in point-of-care diagnostic testing should focus on improving antibody-based assays, monitoring viral loads, and detecting antimicrobial resistance.

Development of Cas13a-based Assays for Neisseria gonorrhoeae Detection and Gyrase A Determination

Background

Neisseria gonorrhoeae is one of the most common bacterial sexually transmitted infections. The emergence of antimicrobial-resistant N. gonorrhoeae is an urgent public health threat. Currently, diagnosis of N. gonorrhoeae infection requires expensive laboratory infrastructure, while antimicrobial susceptibility determination requires bacterial culture, both of which are infeasible in low-resource areas where prevalence is highest. Recent advances in molecular diagnostics, such as Specific High-sensitivity Enzymatic Reporter unLOCKing (SHERLOCK) using CRISPR-Cas13a and isothermal amplification, have the potential to provide low-cost detection of pathogen and antimicrobial resistance.

Methods and Results

We designed and optimized RNA guides and primer-sets for SHERLOCK assays capable of detecting N. gonorrhoeae via the por A gene and of predicting ciprofloxacin susceptibility via a single mutation in the gyrase A ( gyr A) gene. We evaluated their performance using both synthetic DNA and purified N. gonorrhoeae isolates. For por A, we created both a fluorescence-based assay and lateral flow assay using a biotinylated FAM reporter. Both methods demonstrated sensitive detection of 14 N. gonorrhoeae isolates and no cross-reactivity with 3 non-gonococcal Neisseria isolates. For gyr A, we created a fluorescence-based assay that correctly distinguished between 20 purified N. gonorrhoeae isolates with phenotypic ciprofloxacin resistance and 3 with phenotypic susceptibility. We confirmed the gyr A genotype predictions from the fluorescence-based assay with DNA sequencing, which showed 100% concordance for the isolates studied.

Conclusion

We report the development of Cas13a-based SHERLOCK assays that detect N. gonorrhoeae and differentiate ciprofloxacin-resistant isolates from ciprofloxacin-susceptible isolates.

Facilitators and barriers of the implementation of point-of-care devices for cardiometabolic diseases: a scoping review

BACKGROUND

Point-of-care testing (POCT) devices may facilitate the delivery of rapid and timely results, providing a clinically important advantage in patient management. The challenges and constraints in the implementation process, considering different levels of actors have not been much explored. This scoping review aimed to assess literature pertaining to implementation facilitators and barriers of POCT devices for the diagnosis or monitoring of cardiometabolic diseases.

METHODS

A scoping review of the literature was conducted. The inclusion criteria were studies on the inception, planning, or implementation of interventions with POCT devices for the diagnosis or monitoring of cardiometabolic diseases defined as dyslipidemia, cardiovascular diseases, type 2 diabetes, and chronic kidney disease. We searched MEDLINE, Embase, and Global Health databases using the OVID searching engine until May 2022. The Consolidated Framework of Implementation Research (CFIR) was used to classify implementation barriers and facilitators in five constructs. Also, patient, healthcare professional (HCP), and organization level was used.

RESULTS

Twenty studies met the eligibility criteria for data extraction. All studies except two were conducted in high-income countries. Some findings are: 1) Intervention: the most widely recognized facilitator was the quick turnaround time with which results are obtained. 2) Outer setting: at the organizational level, the lack of clear regulatory and accreditation mechanisms has hindered the adoption and sustainability of the use of POCT. 3) Inner setting: for HCP, performing POCT during the consultation was both a facilitator and a barrier in terms of time, personnel, and service delivery. 4) Individuals: the implementation of POCT may generate stress and discomfort in some HCP in terms of training and new responsibilities. 5) Process: for patients, it is highly appreciated that obtaining the sample was simple and more comfortable if venipuncture was not used.

CONCLUSION

This scoping review has described the facilitators and barriers of implementing a POCT device for cardiometabolic conditions using the CFIR. The information can be used to design better strategies to implement these devices and benefit more populations that have low access to cardiometabolic tests.

Diagnostic performance of two rapid tests for syphilis screening in people living with HIV in Cali, Colombia

INTRODUCTION

There is insufficient evidence supporting the use of rapid diagnostic tests (RDTs) for syphilis in people living with HIV (PLWH). We evaluated the diagnostic performance of two commercially available RDTs (Bioline and Determine) in PLWH in Cali, Colombia.

METHODS

A cross-sectional field validation study on consecutive adults with confirmed HIV diagnosis attending three outpatient clinics. Both RDTs were performed on capillary blood (CB), obtained by finger prick, and sera, by venipuncture. A combination of treponemal enzyme linked immunosorbent assay (ELISA) and Treponema pallidum haemagglutination assay (TPHA) on serum samples was the reference standard. Rapid plasma reagin (RPR) and clinical criteria were added to define active syphilis. Sensitivity and specificity, predictive values and likelihood ratios (LR) of RDTs were estimated with their corresponding 95% confidence interval (95% CI). Stratified analyses by sample type, patient characteristics, non-treponemal titers, operator and re-training were performed.

RESULTS

244 PLWH were enrolled, of whom 112 (46%) had positive treponemal reference tests and 26/234 (11.1%) had active syphilis. The sensitivities of Bioline on CB and sera were similar (96.4% vs 94.6%, p = 0.6). In contrast, Determine had a lower sensitivity on CB than sera (87.5% vs 99.1%, p<0.001). Sensitivities were lower in PLWH not receiving ART (Bioline 87.1% and Determine 64.5%, p<0.001) and for one of the operators (Bioline 85% and Determine 60%, p<0.001). Specificities of the RDTs were > 95% in most analyses. Predictive values were 90% or higher. For active syphilis, the RDTs showed a similar performance pattern but with decreased specificities.

CONCLUSION

The studied RDTs have an excellent performance in PLWH to screen for syphilis and potentially for active syphilis, yet Determine performs better on sera than CB. Patient characteristics and potential difficulties operators may face in acquiring enough blood volume from finger pricks should be considered for the implementation and the interpretation of RDTs.

Rapid Antigen Tests during the COVID-19 Era in Korea and Their Implementation as a Detection Tool for Other Infectious Diseases

Rapid antigen tests (RATs) are diagnostic tools developed to specifically detect a certain protein of infectious agents (viruses, bacteria, or parasites). RATs are easily accessible due to their rapidity and simplicity. During the COVID-19 pandemic, RATs have been widely used in detecting the presence of the specific SARS-CoV-2 antigen in respiratory samples from suspected individuals. Here, the authors review the application of RATs as detection tools for COVID-19, particularly in Korea, as well as for several other infectious diseases. To address these issues, we present general knowledge on the design of RATs that adopt the lateral flow immunoassay for the detection of the analyte (antigen). The authors then discuss the clinical utilization of the authorized RATs amidst the battle against the COVID-19 pandemic in Korea and their role in comparison with other detection methods. We also discuss the implementation of RATs for other, non-COVID-19 infectious diseases, the challenges that may arise during the application, the limitations of RATs as clinical detection tools, as well as the possible problem solving for those challenges to maximize the performance of RATs and avoiding any misinterpretation of the test result.

Point-of-Care Testing for the Diagnosis of Fungal Infections

Invasive fungal infections are increasing worldwide due to factors such as climate change and immunomodulating therapies. Unfortunately, the detection of these infections is limited due to the low sensitivity and long periods required for laboratory testing. Point-of-care testing could lead to more rapid diagnosis of these often devasting infections. However, there are currently no true point-of-care tests on the market for the detection of fungi. In this article, the current state of fungal antigen and molecular testing is reviewed, with commentary on the potential for development and use in the point-of-care setting.

Management of Pelvic Inflammatory Disease in Clinical Practice

Pelvic inflammatory disease (PID) is a common reproductive health disorder among women of reproductive age. The treatment of PID has slowly evolved, reflecting changing antibiotic susceptibility and advancements in therapeutics and research; however, it has been largely unchanged over the last several decades. The most recent treatment recommendations consider the severity of infection, clinical presentation, and the polymicrobial nature of the disease. In addition, the role of novel organisms like Mycoplasma genitalium in PID is of emerging significance. PID treatment guidance offers oral and parenteral treatment options based on the patient's clinical status; however, deviations from the published guidelines are a general concern. Point of care (POC) testing for precision care, provision of adherence support, optimizing self-management and prevention strategies, and other alternative or synergistic approaches that maximize treatment outcomes will be instrumental for addressing the current challenges in PID diagnosis and management.

Shifting the power: scale-up of access to point-of-care and self-testing for sexually transmitted infections in low-income and middle-income settings

PURPOSE OF REVIEW

Point-of-care (POC) testing for sexually transmitted infections (STIs) can provide complementary coverage to existing HIV testing services in LMICs. This review summarizes current and emerging technologies for detecting STIs in LMICs, with an emphasis on women, discharge-causing infections (chlamydia, gonorrhoea, trichomoniasis, and syphilis), true POC, self-testing, ethics, and economic considerations related to equitable access.

RECENT FINDINGS

The WHO have recently adapted guidelines for treatment of STIs in women that advise the use of true-POC or near-POC tests to improve case finding. The number of rapid, sensitive, and specific POC diagnostics for STIs has increased significantly over the past 10 years, although adoption of these in low-income and middle-income countries (LMICs) remains limited. Barriers to POC adoption by patients include the cost of tests, the inconvenience of lengthy clinic visits, low perceived risk, stigma, lack of partner notification, and lack of trust in healthcare providers. Lowering the cost of true POC lateral flow devices, interfacing these with digital or eHealth technologies, and enabling self-testing/self-sampling will overcome some of these barriers in LMICs. Ensuring linkage of diagnostic tests to subsequent care remains one of the major concerns about self-testing, irrespective of geography, although available evidence from HIV self-testing suggests that linkage to care is similar to that for facility-based testing.

SUMMARY

Increasing access to sensitive STI true POC tests will strengthen reproductive healthcare in LMICs. Although HIV self-testing is demonstrably useful in LMICs, there is an urgent need for randomized trials evaluating the utility and cost-effectiveness of similar tests for other sexually transmitted infections.

Point-of-Care Diagnostic for Trichomonas vaginalis, the Most Prevalent, Non-Viral Sexually Transmitted Infection

A point-of-care (POC) diagnostic is needed for both women and men to establish universal screening and surveillance for the number one, non-viral sexually transmitted infection (STI) caused by Trichomonas vaginalis. We developed a POC diagnostic for this STI using the MedMira Rapid Vertical Flow (RVF^®) Technology test cartridge with a membrane that includes a Vertical procedural/reagent control line (referred to as CVL) and spotted with 1 µg of a 72.4-kDa truncated version of α-actinin called ACT::SOE3. This protein is a specific diagnostic target for antibody in sera of individuals with trichomoniasis. Serum antibody to ACT::SOE3 is a positive reaction with the test spot. Specificity of ACT::SOE3 was revealed with monoclonal antibodies (MAbs) generated to ACT::SOE3. Addition of negative control serum with MAb 67B reactive to ACT::SOE3 shows detection of both ACT::SOE3 and the CVL. Only positive sera of individuals had antibody reactive with ACT::SOE3 and detected the presence of the spot and the CVL. Negative control sera were unreactive with ACT::SOE3 and only showed the presence of the CVL. Importantly, to show proof-of-principle for POC application, ACT::SOE3 was detected with the positive patient sera spiked with whole blood. Finally, packaged cartridges stored with desiccant packs at 37 °C for one year gave identical results with the positive and negative human sera. Our results show the validity of this new POC serodiagnostic for this STI.

Syndromic Treatment of STIs in Low-income Countries is Inadequate: Current Threats and Future Directions

Sexually transmitted infections (STIs) pose a serious public health threat with more than 1 million curable infections diagnosed every day. While these infections are prevalent globally, the approach to evaluation and treatment varies greatly based on the capacity to make an accurate diagnosis. In low-resource settings, a syndromic approach is often used over an etiologic-based evaluation and management. Syndromic treatment of STIs recognizes groups of symptoms and recommends a multidrug empiric treatment that will cover the most likely causative organisms. By definition, syndromic treatment cannot be used as a screening tool, leaving a large portion of asymptomatic infections untreated. This will lead to the persistence of infection and associated sequelae including pelvic inflammatory disease and infertility. Syndromic treatment also leads to the overtreatment of many infections, which contributes to antimicrobial resistance. The rising threat of Neisseria gonorrhoeae resistance to last-line antibiotics is of global concern. Rapid, accurate, affordable, and easy-to-use point-of-care testing needs to be made readily available to all corners of the world to provide better care to patients and address the growing threat of multidrug resistant organisms. An urgent and collaborative global effort is needed to address the looming threat of a dangerous STI that is resistant to last-line antibiotics.

Therapeutic Options for Chlamydia trachomatis Infection: Present and Future

Sexually transmitted infections (STIs), such as Chlamydia trachomatis (Ct) infection, have serious consequences for sexual and reproductive health worldwide. Ct is one of the most common sexually transmitted bacterial infections in the world, with approximately 129 million new cases per year. C. trachomatis is an obligate intracellular Gram-negative bacterium. The infection is usually asymptomatic, notwithstanding, it could also be associated with severe sequels and complications, such as chronic pain, infertility, and gynecologic cancers, and thus there is an urgent need to adequately treat these cases in a timely manner. Consequently, beyond its individual effects, the infection also impacts the economy of the countries where it is prevalent, generating a need to consider the hypothesis of implementing Chlamydia Screening Programs, a decision that, although it is expensive to execute, is a necessary investment that unequivocally will bring financial and social long-term advantages worldwide. To detect Ct infection, there are different methodologies available. Nucleic acid amplification tests, with their high sensitivity and specificity, are currently the first-line tests for the detection of Ct. When replaced by other detection methods, there are more false negative tests, leading to underreported cases and a subsequent underestimation of Ct infection's prevalence. Ct treatment is based on antibiotic prescription, which is highly associated with drug resistance. Therefore, currently, there have been efforts in line with the development of alternative strategies to effectively treat this infection, using a drug repurposing method, as well as a natural treatment approach. In addition, researchers have also made some progress in the Ct vaccine development over the years, despite the fact that it also necessitates more studies in order to finally establish a vaccination plan. In this review, we have focused on the therapeutic options for treating Ct infection, expert recommendations, and major difficulties, while also exploring the possible avenues through which to face this issue, with novel approaches beyond those proposed by the guidelines of Health Organizations.

Chlamydia trachomatis as a Current Health Problem: Challenges and Opportunities

Chlamydia is one of the most common sexually transmitted bacterial infections (STIs) worldwide. It is caused by Chlamydia trachomatis (CT), which is an obligate intracellular bacterium. In some cases, it can occur in coinfection with other parasites, increasing the pathologic potential of the infection. The treatment is based on antibiotic prescription; notwithstanding, the infection is mostly asymptomatic, which increases the risk of transmission. Therefore, some countries have implemented Chlamydia Screening Programs in order to detect undiagnosed infections. However, in Portugal, there is no CT screening plan within the National Health Service. There is no awareness in the general healthcare about the true magnitude of this issue because most of the methods used are not Nucleic Acid Amplification Technology-based and, therefore, lack sensitivity, resulting in underreporting infection cases. CT infections are also associated with possible long-term severe injuries. In detail, persistent infection triggers an inflammatory milieu and can be related to severe sequels, such as infertility. This infection could also trigger gynecologic tumors in women, evidencing the urgent need for cost-effective screening programs worldwide in order to detect and treat these individuals adequately. In this review, we have focused on the success of an implemented screening program that has been reported in the literature, the efforts made concerning the vaccine discovery, and what is known regarding CT infection. This review supports the need for further fundamental studies in this area in order to eradicate this infection and we also suggest the implementation of a Chlamydia Screening Program in Portugal.

Sensitive and visual identification of Chlamydia trachomatis using multiple cross displacement amplification integrated with a gold nanoparticle-based lateral flow biosensor for point-of-care use

Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infection (STI) and remains a major public health challenge, especially in less-developed regions. Establishing a rapid, inexpensive, and easy-to-interpret point-of-care (POC) testing system for C. trachomatis could be critical for its treatment and limiting further transmission. Here, we devised a novel approach termed a multiple cross displacement amplification integrated with gold nanoparticle-based lateral flow biosensor (MCDA-AuNPs-LFB) for the highly specific, sensitive, user-friendly, and rapid identification of C. trachomatis in clinical samples. A suite of MCDA primers based on the C. trachomatis ompA gene from 14 serological variants (serovar A-K, L1, L2, and L3) were successfully designed and used to establish the assay. Optimal assay conditions were identified at 67°C, and the detection procedure, including nucleic acid preparation (approximately 5 min), MCDA amplification (30 min), and AuNPs-LFB visual readout (within 2 min), was completed within 40 min. The all-in cost for each test was approximately $5.5 USD. The limit of detection (LoD) was 10 copies/reaction, and no cross-reaction was observed with non-C. trachomatis microbes. A total of 135 suspected C. trachomatis-infection genital secretion samples were collected and simultaneously detected using real-time quantitative PCR (qPCR) in our assay. Compared with the qPCR technology, the MCDA-AuNPs-LFB sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 96.20%, 94.92%, and 100%, respectively. Hence, our MCDA-AuNP-LFB assay exhibited considerable potential for POC testing and could be used to identify C. trachomatis in clinical settings, particularly in low-income regions.

Forty Years of Molecular Diagnostics for Infectious Diseases

Nearly 40 years have elapsed since the invention of the PCR, with its extremely sensitive and specific ability to detect nucleic acids via in vitro enzyme-mediated amplification. In turn, more than 2 years have passed since the onset of the coronavirus disease 2019 (COVID-19) pandemic, during which time molecular diagnostics for infectious diseases have assumed a larger global role than ever before. In this context, we review broadly the progression of molecular techniques in clinical microbiology, to their current prominence. Notably, these methods now entail both the detection and quantification of microbial nucleic acids, along with their sequence-based characterization. Overall, we seek to provide a combined perspective on the techniques themselves, as well as how they have come to shape health care at the intersection of technologic innovation, pathophysiologic knowledge, clinical/laboratory logistics, and even financial/regulatory factors.