Advancing prevention of sexually transmitted infections through point-of-care testing: target product profiles and landscape analysis

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.

Near-to-patient-testing to inform targeted antibiotic use for sexually transmitted infections in a public sexual health clinic: the NEPTUNE cohort study

Background

Empiric treatment of sexually transmitted infections can cause unnecessary antibiotic use. We determined if near-to-patient-testing (NPT) for Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium (MG) improved antibiotic-use for a range of clinical presentations.

Methods

Clients attending with non-gonococcal urethritis (NGU), proctitis, as STI-contacts, or for an MG-test-of-cure (MG-TOC) between March and December 2021 were recruited. Participants received near-to-patient-testing (NPT-group) for the three STIs using the GeneXpert® System (Cepheid), and concurrent routine-testing by transcription-mediated-amplification (TMA; Aptima, Hologic). Antibiotic-use among NGU or proctitis cases in the NPT-group was compared to clinic-controls undergoing routine-testing only. The proportion in the NPT-group who notified partners <24 hrs of their STI-specific result was calculated.

Findings

Among 904 consults by 808 NPT-participants, ≥1 STI was detected in 63/252 (25.0%) with NGU, 22/51 (43.1%) with proctitis, and 167/527 (31.7%) STI-contacts. MG was detected among 35/157 (22.3%) MG-TOC consults. Among NGU and proctitis cases, fewer in the NPT-group received empiric treatment compared to clinic-controls (29.4% [95% CI: 24.3-34.9%] vs 83.8% [95% CI: 79.2-87.8%], p < 0.001), resulting in more NPT-group cases appropriately treated (STI-specific drug/no drug appropriately; 80.9% [95% CI: 76.0-85.1%] vs 33.0% [95% CI: 27.7-38.6%], p < 0.001) and fewer mistreated (incorrect drug/treated but pathogen-negative; 17.8% [13.7-22.6%] vs 61.4% [55.6-66.9%], p < 0.001). Of 167/264 in the NPT-group with an STI who responded regarding partner-notification, 95.2% notified all/some partners; 85.9% notified them <24 hrs of the STI-specific result.

Interpretation

Near-to-patient-testing significantly improved antibiotic use and a high proportion of individuals rapidly notified partners of STI-specific results, highlighting the broad benefits of timely diagnostic strategies for STIs in clinical decision making and partner notification.

Funding

ARC ITRP Hub-grant; NHMRC.

Clinic-based evaluation of the dual Xpert CT/NG assay on the GeneXpert System for screening for extragenital chlamydial and gonococcal infections amongst men who have sex with men

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections have increased globally. Asymptomatic infections represent a significant risk of long-term complications. Men who have sex with men (MSM) are disproportionally affected, underscoring the need to offer screening programmes to this population. CT/NG Point of Care Testing (POCT) constitutes a strategic tool to improve the continuum of STI care, however extensive real-life evaluations amongst at risk populations are lacking. The aim of this study is to estimate the GeneXpert CT/NG assay performance and usability for CT and NG at genital and extragenital sites for screening amongst MSM.

METHODS

This study was a multi-site sexual health clinic-based evaluation (Italy, Malta and Peru) with consecutive enrolment. A first void urine sample (divided in two aliquots), two oropharyngeal and two anorectal swabs were collected for each study participant. One specimen set (one for each anatomical site) was tested with the dual index test (Cepheid) at the clinics by the healthcare staff, the other set with FDA/CE approved Nucleic Acid Amplification Tests (NAATs) at the laboratory. Clinical sites and reference laboratories participated in an internal and external quality control programme. Sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values for each anatomical site were estimated using a meta-analytic approach.

RESULTS

One thousand seven hundred two MSM were recruited across all clinical sites for a total of 5049 biological specimens. NG and CT were respectively detected in 274 and 287 of samples. Overall, the NG POCT sensitivity and specificity was 91.43% and 99.75% in urine (LR + 372.80, LR- 0.09), 89.68% and 99.55% in rectal specimens (LR + 197.30, LR- 0.10) and 75.87% and 98.77% at the pharynx respectively (LR + 61.94, LR- 0.24). The CT component of the POCT sensitivity was 84.82% and specificity 99.63% in urine (LR + 228.68, LR- 0.15), 78.07% and 99.19% respectively on rectal site (LR + 96.23, LR-0.22), 67.79% and 99.88% respectively at pharyngeal site (LR + 554.89, LR- 0.32). 95.95% of MSM reported to be willing to wait for POCT results and no provider reported difficulties in terms of performance or interpretation of the results of the Xpert CT/NG.

CONCLUSION

Rapid turnaround time, ease of use and high acceptability make the Xpert CT/NG testing system a strategic tool for increasing testing frequency, reaching those not yet tested and offering the possibility of immediate treatment if needed. The assay showed good negative likelihood ratios and confirms its use to rule out CT/NG infections. Sensitivity varied across sites and pathogens. Periodic staff training at the testing sites should be mandatory.

Novel lateral flow assay for point-of-care detection of Neisseria gonorrhoeae infection in syndromic management settings: a cross-sectional performance evaluation

BACKGROUND

A rapid and affordable point-of-care test is a priority for Neisseria gonorrhoeae control. WHO and Foundation for Innovative New Diagnostics (FIND) have a target product profile for a non-molecular N gonorrhoeae rapid point-of-care test that requires a clinical sensitivity of greater than 80% and a specificity over 95% to be considered useful in syndromic management; test turnaround time should be 30 min or under, and the test should cost less than US$3. A novel lateral flow assay (LFA) was developed to achieve that profile.

METHODS

In this cross-sectional study we evaluated the performance of the novel N gonorrhoeae lateral flow assay (NG-LFA) at the primary health-care level in South Africa. Male patients with urethral discharge syndrome and female patients with vaginal discharge syndrome were recruited from five primary health-care facilities in the Buffalo City Metropolitan Municipality health district of South Africa. First-void urine specimens and nurse-collected vaginal swabs were tested in-facility with the NG-LFA and Xpert CT/NG PCR assay. N gonorrhoeae multi-antigen sequence typing (NG-MAST) was performed on all LFA positive specimens.

FINDINGS

Between March 7, and Sept 19, 2022, we enrolled 200 male patients with urethral discharge and 200 female patients with vaginal discharge. The median age of male patients was 24 years (IQR 21-31 years), and the median age of female patients was 25 years (IQR 21-32 years). In addition, 23 male patients and 12 female patients who presented at the facility with a partner notification slip were enrolled of whom one (4%) and five (42%) were symptomatic, respectively. NG-LFA and Xpert results were available for all participants. In urine specimens, NG-LFA sensitivity was 96·1% (Wilson 95% CI 91·2-98·3; 123 LFA-positive among 128 PCR-positive specimens) and 91·7% in vaginal swab specimens (78·2-97·1; 33 LFA-positive among 36 PCR-positive). The specificity was 97·2% in urine specimens (90·4-99·2; 70 LFA-negative among 72 PCR-negative) and 96·3% in vaginal specimens (92·2-98·3; 158 LFA-negative among 164 PCR-negative). In 156 LFA-positive specimens, NG-MAST showed 93 different sequence types.

INTERPRETATION

The novel NG-LFA had excellent clinical sensitivity and specificity in symptomatic male and female patients. The test met the optimal requirement for sensitivity and the minimal requirement for specificity specified in the target product profile. NG-LFA could provide an important tool to optimise clinical management and reduce excess antibiotic use in settings without direct access to laboratory testing.

FUNDING

Global Antimicrobial Resistance Innovation Fund (GAMRIF) via FIND and National Institutes of Health.

Expert guidance on target product profile development for AMR diagnostic tests

Diagnostics are widely considered crucial in the fight against antimicrobial resistance (AMR), which is expected to kill 10 million people annually by 2030. Nevertheless, there remains a substantial gap between the need for AMR diagnostics versus their development and implementation. To help address this problem, target product profiles (TPP) have been developed to focus developers' attention on the key aspects of AMR diagnostic tests. However, during discussion between a multisectoral working group of 51 international experts from industry, academia and healthcare, it was noted that specific AMR-related TPPs could be extended by incorporating the interdependencies between the key characteristics associated with the development of such TPPs. Subsequently, the working group identified 46 characteristics associated with six main categories (ie, Intended Use, Diagnostic Question, Test Description, Assay Protocol, Performance and Commercial). The interdependencies of these characteristics were then identified and mapped against each other to generate new insights for use by stakeholders. Specifically, it may not be possible for diagnostics developers to achieve all of the recommendations in every category of a TPP and this publication indicates how prioritising specific TPP characteristics during diagnostics development may influence (or not) a range of other TPP characteristics associated with the diagnostic. The use of such guidance, in conjunction with specific TPPs, could lead to more efficient AMR diagnostics development.

Leveraging COVID-era innovation for cervical cancer screening: Clinician awareness and attitudes toward self-sampling and rapid testing for HPV detection

Cervical cancer screening rates are declining in the US, with persistent disparities among vulnerable populations. Strategies to better reach under-screened communities are needed. The COVID pandemic sparked major shifts in healthcare delivery, including the accelerated development and adoption of rapid diagnostic testing, broadened access to remote care, and growing consumer demand for self-testing, which could be leveraged for cervical cancer. Rapid tests for the detection of Human Papillomavirus (HPV) have the potential to improve cervical cancer screening coverage, and if coupled with patient-collected cervicovaginal samples, create an opportunity for self-testing. The objectives of this study were: 1) to examine whether COVID influenced clinician perspectives of rapid testing as a screening modality; and 2) to assess clinician awareness, perceived benefits and limitations, and willingness to adopt point-of-care HPV testing, patient self-sampling, and rapid HPV self-testing with self-collected samples. The methodology adopted consisted of an online cross-sectional survey (n = 224) and in-depth interviews (n = 20) were conducted with clinicians who perform cervical cancer screening in Indiana, ranked in the top ten states for cervical cancer mortality and with marked disparities across socio-demographic groups. The main findings show that about half the clinicians reported that the COVID pandemic had influenced their views on rapid testing as a screening modality both positively (greater public acceptability of rapid testing and impact on patient care) and negatively (concerns regarding accuracy of rapid tests). The majority of clinicians (82%) were willing to adopt rapid HPV testing at the point-of-care, while only 48% were willing to adopt rapid HPV self-testing with self-collected samples. In-depth interviews revealed provider concerns around patients' ability to collect their own sample, report results correctly, and return to the clinic for follow-up and other preventive care. Addressing clinician concerns about self-sampling and rapid HPV testing, such as ensuring that rapid tests include sample adequacy controls, is necessary to mitigate barriers to adoption for cervical cancer screening.

Sexually transmitted infections on the border between Brazil and French Guiana

Purpose

The border between the State of Amapa, Brazil, and French Guiana is mostly primary forest. In the Oyapock basin, socioeconomic circumstances have fueled sex work, gold mining and the circulation of sexually transmitted infections. Given the lack of comprehensive data on this border area, we describe the different sexually transmitted infections along the Brazil/French Guiana border and the testing and care activity.

Methods

We conducted a review of the available scientific and technical literature on sexually transmitted infections in this complex border area. Temporal trends were graphed and for Human Immunodeficiency Virus (HIV) we estimated incidence using the European Center for prevention and Disease Control modeling tool.

Results

Until 2019, 26 of the 46 HIV-infected patients followed and treated in Saint Georges de l'Oyapock were residing on the Brazilian side in Oiapoque. Virological suppression was only achieved for 75% of treated patients; but dropped to 62% during the COVID-19 epidemic. In 2019, cooperation efforts allowed HIV care in Oiapoque, resulting in the transfer of Brazilian patients previously followed on the French side and a substantial increase in the number of patients followed in Oiapoque. The average yearly HIV serological testing activity at the health center in Saint Georges was 16 tests per 100 inhabitants per year; in Camopi it was 12.2 per 100 inhabitants. Modeling estimated the number of persons living with HIV around 170 persons, corresponding to a prevalence of 0.54% and about 40 undiagnosed infections. The model also suggested that there were about 12 new infections per year in Saint Georges and Oiapoque, representing an HIV incidence rate of 3.8 cases per 10,000 per year. HPV prevalence in Saint Georges ranges between 25 and 30% and between 35 and 40% in Camopi. Testing activity for other sexually transmitted infections markedly increased in the past 5 years; the introduction of PCR for chlamydiasis and gonorrhea also had a substantial impact on the number of diagnoses.

Conclusions

The ongoing cooperation between multiple partners on both sides of the border has led to remarkable progress in primary prevention, in testing efforts, in treatment and retention on both sides of the border. In a region with intense health professional turnover, nurturing cooperation and providing accurate assessments of the burden of sexually transmitted infections is essential to tackle a problem that is shared on both sides of the border.

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.

Sexually transmitted infections on the border between Suriname and French Guiana: A scoping review

Purpose

The Maroni basin –delineating the border between Suriname and French Guiana— presents sociocultural, geographical and economic circumstances that have been conducive to the circulation of sexually transmitted infections and to delays in diagnosis and care. Given the scarcity of published data, we aimed to describe different sexually transmitted infections along the Maroni and to gain a broader understanding of the epidemiologic situation.

Methods

We conducted a scoping review of the efforts to approach the problem of sexually transmitted infections in this complex border area. Temporal trends were plotted and crude numbers were divided by local population numbers.

Results

For HIV, despite increasing testing efforts, most patients still present at the advanced HIV stage (median CD4 count at diagnosis is < 20 per mm³), and 25% of patients in Saint Laurent du Maroni were lost to follow-up within 6 years. However, progress on both sides has led to a decline in AIDS cases and mortality. Despite a rapid increase in the 1990’s along the Maroni, the current HIV prevalence seemed lower (0.52%) in the rural villages than in coastal urban centers (> 1%). High risk HPV infection prevalence among women reaches 23.3%. The incidence of gonorrhea was 4.2 per 1,000 population aged 15-59. For chlamydiasis it was 3.4 per 1,000 population aged 15-59. For syphilis, the incidence was 2.5 per 1,000 population aged 15-59. Gonorrhea, chlamydiasis, hepatitis B detection increased over time with greater testing efforts and new diagnostic tests. Since the COVID-19 epidemic, congenital syphilis has dramatically increased in Saint Laurent du Maroni reaching 808 per 100,000 live births.

Conclusion

Sexually transmitted infections seemed more prevalent in Saint Laurent du Maroni –the sole urban center—than in the remote villages along the Maroni. The syndromic approach and the heterogeneity of diagnostic platforms presumably overlook most infections in the region. Therefore, a concerted approach and a shared diagnostic upgrade with molecular diagnosis and rapid diagnostic tests seem necessary to reduce the burden of sexually transmitted infections on both sides of the Maroni. Congenital syphilis resulting from COVID-19 disruption of health services requires urgent attention.

The potential of digital molecular diagnostics for infectious diseases in sub-Saharan Africa

There is a large gap between diagnostic needs and diagnostic access across much of sub-Saharan Africa (SSA), particularly for infectious diseases that inflict a substantial burden of morbidity and mortality. Accurate diagnostics are essential for the correct treatment of individuals and provide vital information underpinning disease surveillance, prevention, and control strategies. Digital molecular diagnostics combine the high sensitivity and specificity of molecular detection with point-of-care format and mobile connectivity. Recent developments in these technologies create an opportunity for a radical transformation of the diagnostic ecosystem. Rather than trying to emulate diagnostic laboratory models in resource-rich settings, African countries have the potential to pioneer new models of healthcare designed around digital diagnostics. This article describes the need for new diagnostic approaches, highlights advances in digital molecular diagnostic technology, and outlines their potential for tackling infectious diseases in SSA. It then addresses the steps that will be necessary for the development and implementation of digital molecular diagnostics. Although the focus is on infectious diseases in SSA, many of the principles apply to other resource-limited settings and to noncommunicable diseases.

Bridging the gap between development of point-of-care nucleic acid testing and patient care for sexually transmitted infections

The incidence rates of sexually transmitted infections (STIs), including the four major curable STIs - chlamydia, gonorrhea, trichomoniasis and, syphilis - continue to increase globally, causing medical cost burden and morbidity especially in low and middle-income countries (LMIC). There have seen significant advances in diagnostic testing, but commercial antigen-based point-of-care tests (POCTs) are often insufficiently sensitive and specific, while near-point-of-care (POC) instruments that can perform sensitive and specific nucleic acid amplification tests (NAATs) are technically complex and expensive, especially for LMIC. Thus, there remains a critical need for NAAT-based STI POCTs that can improve diagnosis and curb the ongoing epidemic. Unfortunately, the development of such POCTs has been challenging due to the gap between researchers developing new technologies and healthcare providers using these technologies. This review aims to bridge this gap. We first present a short introduction of the four major STIs, followed by a discussion on the current landscape of commercial near-POC instruments for the detection of these STIs. We present relevant research toward addressing the gaps in developing NAAT-based STI POCT technologies and supplement this discussion with technologies for HIV and other infectious diseases, which may be adapted for STIs. Additionally, as case studies, we highlight the developmental trajectory of two different POCT technologies, including one approved by the United States Food and Drug Administration (FDA). Finally, we offer our perspectives on future development of NAAT-based STI POCT technologies.

Prevalence of curable STIs and bacterial vaginosis during pregnancy in sub-Saharan Africa: a systematic review and meta-analysis

OBJECTIVE

STIs remain a global public health problem with a high burden among pregnant women. STIs in pregnant women may lead to various adverse pregnancy outcomes. In most sub-Saharan African countries, syndromic management is used for screening and treatment of STIs. We aimed to update and summarise pooled prevalence of curable STIs and bacterial vaginosis (BV) among pregnant women in sub-Saharan Africa.

METHODS

Electronic databases and reference lists of relevant published and unpublished studies were searched from March 2015 to October 2020. Studies were included if they estimated prevalence of Chlamydia trachomatis (CT), Trichomonas vaginalis (TV), Neisseria gonorrhoeae (NG), Treponema pallidum (syphilis), Mycoplasma genitalium (MG) and BV among pregnant women in sub-Saharan Africa. Meta-analyses were performed with observed prevalences corrected for diagnostic errors to estimate the pooled prevalence of diagnosed infections by region.

RESULTS

A total of 48 studies met the inclusion criteria, providing 85-point prevalence estimates for curable STIs and BV. Pooled prevalence estimates (with 95% CI and number of women tested) were as follows: MG: 13.5% (4.0-27.2, n=1076); CT: 10.8% (6.9-15.5, n=6700); TV: 13.8% (10.0-18.0, n=9264); NG: 3.3% (2.1-4.7, n=6019); syphilis: 2.9% (2.0-4.0, n=95 308) and BV: 36.6% (27.1-46.6, n=5042). By region, BV was the most prevalent and ranged from 28.5% (24.5-32.8, n=1030) in Eastern Africa to 52.4% (33.5-70.9, n=2305) in Southern Africa; NG had the lowest prevalence, ranging from 1.4% (95% CI 0.1 to 3.1, n=367) in Central Africa to 4.4% (95% CI 2.6 to 6.4, n=4042) in Southern Africa.

CONCLUSION

The prevalence of curable STIs and BV in sub-Saharan Africa is substantial in pregnant women but most prevalent in Southern Africa where HIV prevalence is highest. It is crucial to integrate screening of curable STIs into antenatal care programmes that have previously focused on diagnosis and treatment of syphilis and HIV.

Molecular chlamydia and gonorrhoea point of care tests implemented into routine practice: Systematic review and value proposition development

BACKGROUND

Sexually Transmitted Infections, including Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT), continue to be a global health problem. Increased access to point-of-care-tests (POCTs) could help detect infection and lead to appropriate management of cases and contacts, reducing transmission and development of reproductive health sequelae. Yet diagnostics with good clinical effectiveness evidence can fail to be implemented into routine care. Here we assess values beyond clinical effectiveness for molecular CT/NG POCTs implemented across diverse routine practice settings.

METHODS

We conducted a systematic review of peer-reviewed primary research and conference abstract publications in Medline and Embase reporting on molecular CT/NG POCT implementation in routine clinical practice until 16th February 2021. Results were extracted into EndNote software and initially screened by title and abstract by one author according to the inclusion and exclusion criteria. Articles that met the criteria, or were unclear, were included for full-text assessment by all authors. Results were synthesised to assess the tests against guidance criteria and develop a CT/NG POCT value proposition for multiple stakeholders and settings.

FINDINGS

The systematic review search returned 440 articles; 28 were included overall. The Cepheid CT/NG GeneXpert was the only molecular CT/NG POCT implemented and evaluated in routine practice. It did not fulfil all test guidance criteria, however, studies of test implementation showed multiple values for test use across various healthcare settings and locations. Our value proposition highlights that the majority of values are setting-specific. Sexual health services and outreach services have the least overlap, with General Practice and other non-sexual health specialist services serving as a "bridge" between the two.

CONCLUSIONS

Those wishing to improve CT/NG diagnosis should be supported to identify the values most relevant to their settings and context, and prioritise implementation of tests that are most closely aligned with those values.

The relevance of target product profiles for manufacturers, experiences from the World Health Organization initiative for point-of-care testing for sexually transmitted infections

Background

Sexually transmitted infections (STIs) are a significant global public health issue that cause a high burden of disease, especially in low- and middle-income countries. Screening of key populations and early and accurate diagnosis of infection are critical. Testing for syphilis, Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, curable STIs, as well as the human papillomavirus (HPV), is frequently unavailable in low-resource settings. Tests for these STIs that can be used at the point of patient care (POCTs) are needed.

In recent years, there has been increased attention for STI POCTs, but technical guidance, financial resources and advocacy for additional platforms/tests are required in order to foster the development of STI POCTs. The WHO Department of Sexual and Reproductive Health and Research (SRH) has developed target product profiles (TPPs), a form of technical guidance, for these STI diagnostics.

Methods

SRH conducted a survey of selected companies that are developing POCTs for one or more of the STIs mentioned above to better understand how these TPPs influence the diagnostic development process – to assess their impact.

Results

Survey respondents indicated that the STI POCT TPPs provided good guidance with respect to performance expectations and operational characteristics for the tests/platforms. In particular, optimal metrics for sensitivity, specificity, sample types, and time to result were considered to be very useful.

Respondents also suggested ways to improve the relevance of the STI POCT TPPs. For example, since it is often not possible for developers to achieve every desired standard, it would be useful to prioritize each performance/operational characteristic of the test and to provide a rationale as to why certain characteristics are considered important.

Respondents also emphasized the need to encourage industry participation in the TPP development process and to find creative ways, including via targeted emails, a WHO webpage directed at industry, or a coordinated communications plan to increase awareness of the TPPs.

Conclusions

Companies value the STI POCT TPPs and want them to continue. In order to maximize impact, WHO should consider the proposals from the manufacturers in the interest of increasing and accelerating access to STI diagnostics and treatment in low-resource settings.

A Narrative Review of Where We Are With Point-of-Care Sexually Transmitted Infection Testing in the United States

BACKGROUND

Point-of-care (POC) tests enable immediate diagnosis and targeted treatment of sexually transmitted infections (STIs), which could accelerate control of ongoing epidemics. Although older nucleic acid amplification tests have improved the accuracy of laboratory-based tests for STIs, newer POC tests can facilitate control efforts. We sought to review the performance and time to result of POC assays for STIs in the last 10 years.

METHODS

The authors performed a PubMed, US National Library of Medicine, National Center for Biotechnology Information search for POC tests for STIs or sexually transmitted diseases.

RESULTS

Diagnostic technology for POC assays for STIs has achieved high sensitivity and specificity (>90%) using recent molecular advances in the last 10 years. Three POC tests for chlamydia and gonorrhea and 2 for trichomonas have been cleared by the Food and Drug Administration and can provide rapid results during the clinical encounter. Two POC assays for syphilis are now cleared by the Food and Drug Administration. Other similar POC assays are in development. These "fast followers" have faster time to result and will extend the diagnostic armamentarium at POC.

CONCLUSIONS

New technology has improved the performance accuracy of STI POC diagnostics. Innovation in device format has resulted in accurate POC assays, which can decrease the time to result and accelerate the detection and treatment of STIs during the clinical encounter. The full implementation potential of these newer tests will depend on the ability of these tests to achieve Clinical Laboratory Improvement Amendments-waived status so they can be performed by nonlaboratorians with no previous training.

Performance of point-of-care tests for the detection of chlamydia trachomatis infections: A systematic review and meta-analysis

BACKGROUND

Chlamydia trachomatis (CT) is one of the most prevalent bacterial sexually transmitted infections (STIs) globally but has been inadequately detected for intervention. Introduction of point-of-care tests (POCTs) for CT is critical for filling the intervention gaps. We conducted a systematical review and meta-analysis on diagnostic performance of POCTs for CT to assist in guiding the application of these assays in CT screening and detection.

METHODS

We searched PubMed/Medline and Embase databases, from January 2004 to May 2021, for studies reporting the performance of POCTs for identifying CT using specimens collected from urethral, vaginal, cervical, anorectal, or pharyngeal site or of urine. Two investigators independently screened and extracted data for controlling the quality of data extraction. Any discrepancies in study selection and data extraction were resolved through consensus. We only included studies with sufficient data to estimate sensitivity and specificity, and used laboratory-based nucleic acid amplification test (NAAT) as the reference standard. The main outcomes were pooled sensitivity, specificity, and diagnostic odds ratio (DOR) and their corresponding 95% confidence intervals (CIs). Summary estimates were calculated using a random-effects model and summary receiver operator curves (SROCs) were generated using the Moses-Littenberg method. STATA 14.0 and Meta-DiSc 1.4 were used for statistical analysis. The study protocol is registered with PROSPERO, number CRD42019140544.

FINDINGS

Of 3,038 records identified, 39 studies (42,336 specimens) were included in the study, including 14 studies on evaluation of antigen detection (AD)-based and 25 on NAAT-based POCTs. The overall pooled sensitivity, specificity and DOR were 56% (95% CI 45%-67%), 99% (95% CI 98%-99%) and 86 (95% CI 46-163), respectively, for AD-based POCTs and corresponding values for NAAT-based POCTs were 94% (95% CI 91%-96%), 99% (95% CI 99%-99%) and 1,933(95% CI 1,018-3,669), respectively. The pooled sensitivity of AD-based POCTs varied across the types of specimens, indicating 46% for cervical swabs (95% CI 37%-56%; range 22.7%-71.4%), 52% for vaginal swabs (95% CI 34%-70%; range 17.1%-86.8%) and 57% for male urine (95% CI 36%-75%; range 20.0%-82.6%). For NAAT-based POCTs, the pooled sensitivity was 94% (95% CI 90%-96%) for cervical swabs, 94% (95% CI 86%-98%) for vaginal swabs, 95% (95% CI 91%-97%) for urine specimens and 93% (95% CI 87%-96%) for anorectal swabs.

INTERPRETATION

NAAT-based POCTs for CT have a significantly better performance particularly in sensitivity for diagnosing the infection with CT than the AD-based POCTs. Screening strategy with AD-based POCTs may potentially result in a substantial under-detection of the infections.

Point-of-care testing for sexually transmitted infections in low-resource settings

BACKGROUND

Both the global incidence and prevalence of sexually transmitted infections continue to increase, affecting hundreds of millions of individuals, particularly in low-to middle-income countries. While a definitive diagnosis is desirable to inform STI treatment, syndromic management is the most widely used strategy in resource-limited settings. With the development of point-of-care (POC) tests, it is important to discuss how laboratories will need to adapt to new training and supervisory roles in support of testing which will largely be performed by peripheral clinical staff.

OBJECTIVES

To discuss potential applications of STI POC tests, how they could improve existing STI control strategies and the role of clinical and reference laboratories in support of initiatives to improve STI management and control activities.

SOURCES

Narrative literature review and expert opinion.

CONTENT

The paper outlines the current status of the STI epidemic worldwide and discusses the problems associated with current approaches to control these infections, particularly in low resource settings. The roles of clinical and reference laboratories will need to change in order to provide support for POC and near-patient STI testing as these technologies are introduced into clinical as well as laboratory settings.

IMPLICATIONS

Laboratories will be expected to play a leading role in the introduction and implementation of POC and near-patient STI testing. They will be required to facilitate training and provide technical and supervisory support to clinical staff on the use of these technologies to augment existing STI management and surveillance programs. In order to provide quality service, they will need to develop, introduce and maintain sustainable local QC and EQA systems. Evidence from implementation research for introduction and scale up of STI POCTs in different STI epidemic and laboratory infrastructure settings is required.

Analytical validation of GMEX rapid point-of-care CYP2C19 genotyping system for the CHANCE-2 trial

Background and purpose

Rapid genotyping is useful for guiding early antiplatelet therapy in patients with high-risk nondisabling ischaemic cerebrovascular events (HR-NICE). Conventional genetic testing methods used in CYP2C19 genotype-guided antiplatelet therapy for patients with HR-NICE did not satisfy the needs of the Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE)-2 trial. Therefore, we developed the rapid-genotyping GMEX (point-of-care) system to meet the needs of the CHANCE-2 trial.

Methods

Healthy individuals and patients with history of cardiovascular diseases (n=408) were enrolled from six centres of the CHANCE-2 trial. We compared the laboratory-based genomic test results with Sanger sequencing test results for accuracy verification. Next, we demonstrated the accuracy, timeliness and clinical operability of the GMEX system compared with laboratory-based technology (YZY Kit) to verify whether the GMEX system satisfies the needs of the CHANCE-2 trial.

Results

Genotypes reported by the GMEX system showed 100% agreement with those determined by using the YZY Kit and Sanger sequencing for all three CYP2C19 alleles (*2, *3 and *17) tested. The average result’s turnaround times for the GMEX and YZY Kit methods were 85.0 (IQR: 85.0–86.0) and 1630.0 (IQR: 354.0–7594.0) min (p<0.001), respectively.

Conclusions

Our data suggest that the GMEX system is a reliable and feasible point-of-care system for rapid CYP2C19 genotyping for the CHANCE-2 trial or related clinical and research applications.

Missed opportunities for sexually transmitted infections testing for HIV pre-exposure prophylaxis users: a systematic review

INTRODUCTION

Given the synergistic relationship between HIV and sexually transmitted infections (STI), the integration of services has the potential to reduce the incidence of both HIV and STIs. We explored the extent to which STI testing has been offered within HIV pre-exposure prophylaxis (PrEP) programmes worldwide.

METHODS

We conducted a systematic review of PrEP programmes implementing STI testing services in nine databases. We approached PrEP implementers for additional unpublished data and implementation details. Descriptive statistics were used to present the characteristics of STI testing within PrEP programmes. Content analysis of the input from PrEP implementers was conducted to summarize the barriers to and facilitators of STI testing.

RESULTS

Of 9,161 citations, 91 studies conducted in 32 countries were included: 69% from high-income countries (HICs) and 64% from programmes targeting men who have sex with men (MSM) and transgender women (TGW) only. The majority of programmes (70%, 64/91) conducted STI testing before the initiation of PrEP. The most common STIs tested were gonorrhoea (86%, 78/91), chlamydia (84%, 76/91) and syphilis (84%, 76/91). The majority provided STI testing at three-month intervals (70%, 53/76, for syphilis; 70% 53/78, for chlamydia; 68%, 53/78, for gonorrhoea). Relative to low- and middle-income countries (LMICs), a higher proportion of PrEP programmes in HICs offered testing for gonorrhoea (92% vs. 71%, p < 0.05), chlamydia (92% vs. 64%, p < 0.01), syphilis (87% vs. 75%, p < 0.05), hepatitis A (18% vs. 4%, p < 0.05) and hepatitis C (43% vs. 21%, p < 0.05); offered testing for a higher number of STIs (mean 3.75 vs. 3.04, p < 0.05); and offered triple (throat, genital/urine and anorectal) anatomical site screening (54% vs. 18%, p < 0.001). Common implementation challenges included costs, access to STI diagnostics, programme logistics of integrating STI testing into PrEP delivery models and lack of capacity building for staff involved in PrEP provision.

CONCLUSIONS

Significant gaps and challenges remain in the provision of STI testing services within HIV PrEP programmes. We recommend more active integration of STI testing and management into PrEP programmes, supported by standardized practice guidelines, staff capacity building training and adequate funding. This could lead to improved sexual health and HIV outcomes in key populations.

Current and Future Trends in the Laboratory Diagnosis of Sexually Transmitted Infections

Sexually transmitted infections (STIs) continue to exert a considerable public health and social burden globally, particularly for developing countries. Due to the high prevalence of asymptomatic infections and the limitations of symptom-based (syndromic) diagnosis, confirmation of infection using laboratory tools is essential to choose the most appropriate course of treatment and to screen at-risk groups. Numerous laboratory tests and platforms have been developed for gonorrhea, chlamydia, syphilis, trichomoniasis, genital mycoplasmas, herpesviruses, and human papillomavirus. Point-of-care testing is now a possibility, and microfluidic and high-throughput omics technologies promise to revolutionize the diagnosis of STIs. The scope of this paper is to provide an updated overview of the current laboratory diagnostic tools for these infections, highlighting their advantages, limitations, and point-of-care adaptability. The diagnostic applicability of the latest molecular and biochemical approaches is also discussed.

[Rapid diagnosis of sexually transmitted infections : Joint statement of DSTIG, RKI, and PEI, as well as the reference centers for HIV, HBV, and HCV and consulting laboratories for Chlamydia, gonococci, and Treponema pallidum]

In February 2019, the fourth expert meeting on rapid diagnostic tests (RDTs) for sexually transmitted infections (STI) was held at the Robert Koch Institute (RKI) in Berlin. Novel technical developments and new aspects of RDT applications were discussed by representatives from the German STI Society (DSTIG); RKI; the Paul Ehrlich Institute; national reference centers for HIV, HBV, and HCV; and reference laboratories for Chlamydia, gonococci, and Treponema pallidum.As a result of this meeting, we present a revision of the joint statement on STI diagnostics with RDTs from 2017. The Regulation (EU) 2017/746 of the European Parliament and of the Council on in vitro diagnostic medical devices became effective in May 2017 and includes more stringent regulatory requirements for RDTs, mainly concerning conformity of manufacturing processes and performance characteristics of class D in vitro diagnostics (detection of HIV, HBV, HCV, and T. pallidum). Some RDTs for HIV, HCV, and T. pallidum have been evaluated in clinical studies and/or were WHO prequalified and may be used in low-threshold services. Among them are some HIV RDTs available and approved for self-testing. In addition, some HBV RDTs based on detection of HBs antigen (HBsAg) received WHO prequalification. However, false negative results may occur in samples with low HBsAg levels, as for instance in HIV-coinfected patients receiving antiretroviral therapy. For Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), antigen-based RDTs still do not allow reliable detection of infection. Only PCR-based CT/NG RDTs possess sufficient diagnostic accuracy to be used as point-of-care tests. Rapid PCR tests for NG, however, do not provide any information about antimicrobial resistance.

Point of Care Diagnostics in Resource-Limited Settings: A Review of the Present and Future of PoC in Its Most Needed Environment

Point of care (PoC) diagnostics are at the focus of government initiatives, NGOs and fundamental research alike. In high-income countries, the hope is to streamline the diagnostic procedure, minimize costs and make healthcare processes more efficient and faster, which, in some cases, can be more a matter of convenience than necessity. However, in resource-limited settings such as low-income countries, PoC-diagnostics might be the only viable route, when the next laboratory is hours away. Therefore, it is especially important to focus research into novel diagnostics for these countries in order to alleviate suffering due to infectious disease. In this review, the current research describing the use of PoC diagnostics in resource-limited settings and the potential bottlenecks along the value chain that prevent their widespread application is summarized. To this end, we will look at literature that investigates different parts of the value chain, such as fundamental research and market economics, as well as actual use at healthcare providers. We aim to create an integrated picture of potential PoC barriers, from the first start of research at universities to patient treatment in the field. Results from the literature will be discussed with the aim to bring all important steps and aspects together in order to illustrate how effectively PoC is being used in low-income countries. In addition, we discuss what is needed to improve the situation further, in order to use this technology to its fullest advantage and avoid “leaks in the pipeline”, when a promising device fails to take the next step of the valorization pathway and is abandoned.

Developing target product profiles for Neisseria gonorrhoeae diagnostics in the context of antimicrobial resistance: An expert consensus

BACKGROUND

There is a need for a rapid diagnostic point of care test to detect Neisseria gonorrhoeae (NG) infection to prevent incorrect, lack or excess of treatment resulting from current syndromic management in low-resource settings. An assay to identify NG antimicrobial resistance (AMR) is also highly desirable to facilitate antibiotic stewardship. Here we describe the development of two target product profiles (TPPs): one for a test for etiological diagnosis of NG and Chlamydia trachomatis (CT) (TPP1) and one for the detection of NG AMR/susceptibility (TPP2).

METHODS

Draft TPPs were initially developed based on a landscape analysis of existing diagnostics and expert input. TPPs were refined via an online Delphi survey with two rounds of input from 68 respondents. TPP characteristics on which <75% of non-industry respondents agreed were further discussed and revised by an expert working group.

RESULTS

The need for a test to identify NG in patients with urethral or vaginal discharge was identified as a minimal requirement of TPP1, with a test that can diagnose NG in asymptomatic patients as the optimal requirement. A sensitivity of 80% was considered acceptable, either in context of syndromic management or screening high-risk populations. For TPP2, the agreed minimal requirement was for a test to be used at level 2 healthcare facilities and above, with an optimal requirement of level 1 or above. A lateral flow format was preferred for TPP1, while it was considered likely that TPP2 would require a molecular format. A total of 31 test characteristics were included in TPP1 and 27 in TPP2.

CONCLUSIONS

Following the working group revisions, TPPs were posted online for public feedback for two months, and are now finalized. The final TPPs are currently guiding the development of new diagnostics that meet the defined characteristics to reach the market within two years.

Overcoming Challenges with the Adoption of Point-of-Care Testing: From Technology Push and Clinical Needs to Value Propositions

Major technical challenges often prevent developers from producing new point-of-care technologies that deliver the required clinical performance in the intended settings of use. But even when devices meet clinical requirements, they can fail to be adopted and successfully implemented. Adoption barriers occur when decision makers do not understand the "value proposition" of new technologies. Current discussions of value in the context of point-of-care testing focus predominantly on the intended use and performance of the device from the manufacturer's point-of-view. However, the perspective of potential adopters in determining whether new devices provide value is also important, as is the opinion of all stakeholders who will be impacted. Incorporating value concepts into decisions made across the full development-to-adoption continuum can increase the likelihood that point-of-care testing will have the desired impact on health care delivery and patient outcomes. This article discusses how various approaches to technology development impact adoption and compares the characteristics of these approaches to emerging value concepts. It also provides an overview of value initiatives and tools that are being developed to support the evaluation of value propositions. These are presented for a range of technology adoption decision contexts, with particular applicability to point-of-care testing. Expanding the focus of research to address gaps in both the creation and evaluation of value propositions is imperative in order for value concepts to positively influence the adoption of point-of-care testing.

Advancing Prevention of STIs by Developing Specific Serodiagnostic Targets: Trichomonas vginalis as a Model

Point-of-Care (POC) serum antibody screening of large cohorts of women and men at risk for the sexually transmitted infection (STI) caused by Trichomonas vaginalis requires the availability of targets with high specificity. Such targets should comprise epitopes unique to T. vaginalis immunogenic proteins detected by sera of women and men patients with trichomonosis but not uninfected controls. Three enzymes to which patients make serum IgG antibody were identified as fructose-1,6-bisphosphate aldolase (A), α-enolase (E), and glyceraldehyde-3-phosphate dehydrogenase (G). Epitopes within these proteins were identified that had no sequence identity to enzymes of humans and other pathogens. Therefore, I constructed a chimeric recombinant String-Of-Epitopes (SOE) protein consisting of 15-mer peptides, within which are the epitopes of A, E, and G. This novel protein of ~36-kD is comprised of two epitopes of A, ten epitopes of E, and seven epitopes of G (AEG::SOE2). The AEG::SOE2 protein was detected both by immunoblot and by enzyme-linked immunosorbent assay (ELISA) using highly reactive sera of women and men but not negative serum unreactive to T. vaginalis proteins. Finally, AEG::SOE2 was found to be immunogenic, as evidenced by serum IgG from immunized mice. I discuss how this approach is important in relation to infectious disease diagnostic targets for detection of serum IgG antibody in exposed and/or infected individuals and how such novel targets may have potential as subunit vaccine candidates against microbial pathogens.

Point-by-Point Progress: Gonorrhea Point of Care Tests

INTRODUCTION

Point-of-care (POC) tests for Neisseria gonorrhoeae (Ng) are urgently needed to control the gonorrhea epidemic, so patients can receive immediate diagnoses and treatment. While the advent of nucleic acid amplification tests (NAATs) has improved the accuracy of Ng identification, very few POC assays are able to provide results of such tests at the clinical visit. Additionally, antimicrobial resistance (AMR) presents a unique treatment challenge for Ng.

AREAS COVERED

This review notes that older POC tests have lower sensitivity for Ng, compared to the currently-available NAATs, and are not adequate for the current demand for high sensitivity. Promising newer assays, which can be used at the POC are covered. This review also includes data about clinicians' and patients' acceptability and expectations of POC tests for Ng, testing of extragenital specimens, pooling studies, as well as their impact clinically, and use in low-resource settings.

EXPERT OPINION

The ability to use POC tests to identify and immediately treat Ng infections at the patient encounter offers many benefits and opportunities. POC tests for Ng are currently available, but not widely used especially in low-resource settings. Further development of POC tests with AMR testing capacity is needed to help guide antimicrobial stewardship.

Gonococcal vaccines: Public health value and preferred product characteristics; report of a WHO global stakeholder consultation, January 2019

Renewed interest in developing vaccines against Neisseria gonorrhoeae has been sparked by the increasing threat of gonococcal antimicrobial resistance (AMR) and growing optimism that gonococcal vaccines are biologically feasible. Evidence suggests serogroup B Neisseria meningitidis vaccines might provide some cross-protection against N. gonorrhoeae, and new gonococcal vaccine candidates based on several approaches are currently in preclinical development. To further stimulate investment and accelerate development of gonococcal vaccines, greater understanding is needed regarding the overall value that gonococcal vaccines might have in addressing public health and societal goals in low-, middle-, and high-income country contexts and how future gonococcal vaccines might be accepted and used, if available. In January 2019, the World Health Organization (WHO) convened a multidisciplinary international group of experts to lay the groundwork for understanding the potential health, economic, and societal value of gonococcal vaccines and their likely acceptance and use, and for developing gonococcal vaccine preferred product characteristics (PPCs). WHO PPCs describe preferences for vaccine attributes that would help optimize vaccine value and use in meeting the global public health need. This paper describes the main discussion points and conclusions from the January 2019 meeting of experts. Participants emphasized the need for vaccines to control N. gonorrhoeae infections with the ultimate goals of preventing adverse sexual and reproductive health outcomes (e.g., infertility) and reducing the impact of gonococcal AMR. Meeting participants also discussed important PPC considerations (e.g., vaccine indications, target populations, and potential immunization strategies) and highlighted crucial research and data needs for guiding the value assessment and PPCs for gonococcal vaccines and advancing gonococcal vaccine development.

Target Product Profiles for medical tests: a systematic review of current methods

BACKGROUND

A Target Product Profile (TPP) outlines the necessary characteristics of an innovative product to address an unmet clinical need. TPPs could be used to better guide manufacturers in the development of 'fit for purpose' tests, thus increasing the likelihood that novel tests will progress from bench to bedside. However, there is currently no guidance on how to produce a TPP specifically for medical tests.

METHODS

A systematic review was conducted to summarise the methods currently used to develop TPPs for medical tests, the sources used to inform these recommendations and the test characteristics for which targets are made. Database and website searches were conducted in November 2018. TPPs written in English for any medical test were included. Based on an existing framework, test characteristics were clustered into commonly recognised themes.

RESULTS

Forty-four TPPs were identified, all of which focused on diagnostic tests for infectious diseases. Three core decision-making phases for developing TPPs were identified: scoping, drafting and consensus-building. Consultations with experts and the literature mostly informed the scoping and drafting of TPPs. All TPPs provided information on unmet clinical need and desirable analytical performance, and the majority specified clinical validity characteristics. Few TPPs described specifications for clinical utility, and none included cost-effectiveness.

CONCLUSIONS

We have identified a commonly used framework that could be beneficial for anyone interested in drafting a TPP for a medical test. Currently, key outcomes such as utility and cost-effectiveness are largely overlooked within TPPs though and we foresee this as an area for further improvement.

Call to action for health systems integration of point-of-care testing to mitigate the transmission and burden of sexually transmitted infections

Objectives

In 2016, WHO estimated 376 million new cases of the four main curable STIs: gonorrhoea, chlamydia, trichomoniasis and syphilis. Further, an estimated 290 million women are infected with human papillomavirus. STIs may lead to severe reproductive health sequelae. Low-income and middle-income countries carry the highest global burden of STIs. A large proportion of urogenital and the vast majority of extragenital non-viral STI cases are asymptomatic. Screening key populations and early and accurate diagnosis are important to provide correct treatment and to control the spread of STIs. This article paints a picture of the state of technology of STI point-of-care testing (POCT) and its implications for health system integration.

Methods

The material for the STI POCT landscape was gathered from publicly available information, published and unpublished reports and prospectuses, and interviews with developers and manufacturers.

Results

The development of STI POCT is moving rapidly, and there are much more tests in the pipeline than in 2014, when the first STI POCT landscape analysis was published on the website of WHO. Several of the available tests need to be evaluated independently both in the laboratory and, of particular importance, in different points of care.

Conclusion

This article reiterates the importance of accurate, rapid and affordable POCT to reach universal health coverage. While highlighting the rapid technical advances in this area, we argue that insufficient attention is being paid to health systems capacity and conditions to ensure the swift and rapid integration of current and future STI POCT. Unless the complexity of health systems, including context, institutions, adoption systems and problem perception, are recognised and mapped, simplistic approaches to policy design and programme implementation will result in poor realisation of intended outcomes and impact.

Laboratory Diagnosis of Sexually Transmitted Infections in Cases of Suspected Child Sexual Abuse

Laboratory diagnosis of microbial agents associated with sexually transmitted infections plays an important role in both the care of victims of child sexual abuse (CSA) and the investigation of suspected CSA incidents, with law enforcement implications. Rapid and sensitive test results prompt immediate actions to treat and protect the victimized children. The development and maturation of automated nucleic acid amplification tests (NAATs) has greatly improved the assay sensitivity and specificity, with only a 1- to 2-h turnaround time. Unfortunately, the performance characteristics of NAATs have been determined largely with a few limited specimen types and evaluated in adults only. This minireview attempts to cover the scope of infectious agents potentially implicated in CSA, specimen collection, laboratory test modalities, and laboratory report constraints, further complicated by infrequently collected specimen types from prepubertal children <13 years of age.

Evaluation of Rapid Syphilis Testing Using the Syphilis Health Check in Florida, 2015-2016

The Syphilis Health Check (SHC) had low estimated specificity (91.5%) in one Florida county. We investigated use of SHC by a range of Florida publicly-funded programs between 2015 and 2016 to estimate specificity, positive predictive value (PPV), field staff acceptance, and impacts on programmatic outcomes. All reported SHC results were extracted from routinely collected program data. Field staff were surveyed about SHC's utility. Analyses investigated differences between SHC and traditional syphilis testing outcomes. Of 3,630 SHC results reported, 442 were reactive; 92 (20.8%) had prior diagnoses of syphilis; 7 (1.6%) had no further testing. Of the remaining 343; 158 (46.0%) were confirmed cases, 168 (49.0%) were considered false-positive, and 17 (5.0%) were not cases but not clearly false-positive. Estimated specificity of SHC was 95.0%. Overall, 48.5% of positives became confirmed cases (PPV). PPV varied according to prevalence of syphilis in populations tested. Staff (90%) thought SHC helped identify new cases but expressed concern regarding discordance between reactive SHC and lab-based testing. Programmatic outcomes assessment showed shorter time to treatment and increased numbers of partners tested for the SHC group; these enhanced outcomes may better mitigate the spread of syphilis compared to traditional syphilis testing alone, but more research is needed.

A paperfluidic platform to detect Neisseria gonorrhoeae in clinical samples

Globally, the microbe Neisseria gonorrhoeae (NG) causes 106 million newly documented sexually transmitted infections each year. Once appropriately diagnosed, NG infections can be readily treated with antibiotics, but high-risk patients often do not return to the clinic for treatment if results are not provided at the point of care. A rapid, sensitive molecular diagnostic would help increase NG treatment and reduce the prevalence of this sexually transmitted disease. Here, we report on the design and development of a rapid, highly sensitive, paperfluidic device for point-of-care diagnosis of NG. The device integrates patient swab sample lysis, nucleic acid extraction, thermophilic helicase-dependent amplification (tHDA), an internal amplification control (NGIC), and visual lateral flow detection within an 80 min run time. Limits of NG detection for the NG/NGIC multiplex tHDA assay were determined within the device, and clinical performance was validated retroactively against qPCR-quantified patient samples in a proof-of-concept study. This paperfluidic diagnostic has a clinically relevant limit of detection of 500 NG cells per device with analytical sensitivity down to 10 NG cells per device. In triplicate testing of 40 total urethral and vaginal swab samples, the device had 95% overall sensitivity and 100% specificity, approaching current laboratory-based molecular NG diagnostics. This diagnostic platform could increase access to accurate NG diagnoses to those most in need.