Cost and cost-effectiveness of point-of-care testing and treatment for sexually transmitted and genital infections in pregnancy in low-income and middle-income countries: a systematic review protocol

Overview of point-of-care diagnostic options for detection of chlamydia trachomatis: current technology and implementation considerations

INTRODUCTION

Chlamydia trachomatis continues to be the most common bacterial infection worldwide and rates continue to increase despite long-standing control efforts. Point of care (POC) testing options may offer improvements in case finding that lead to improved control of this sexually transmitted infection (STI).

AREAS COVERED

This review will provide information on the three tests that have US Food and Drug Administration (FDA) clearance and describe assays in the developmental pipeline. The review will also provide implementation evaluations of the existing tests and offer suggestions about factors to consider prior to adoption of these or newer tests as they become available.

EXPERT OPINION

Technology is developing rapidly and may soon offer many choices of rapid diagnostic tools which can be used in clinical settings to detect chlamydial infections, particularly in underserved populations. The key to successful deployment of new tests will rest on data generated by implementation research to identify the features that create barriers or facilitate adoption of a new clinical paradigm.

Advantages of Syndromic Diagnostics: Detection of the Pathogens Causing Urethritis/Cervicitis with the STI CNM Real-Time PCR Kit from Vitro S.A

The STI CNM Real-Time PCR Kit from Vitro S.A. (Spain) demonstrates high sensitivity and specificity, is cost-effective, and can detect the three main etiological agents of urethritis/cervicitis in a single multiplex PCR. Sexually transmitted infections (STIs) are a significant public health problem and a significant burden of morbidity and mortality in hospitals. The World Health Organization (WHO) estimates the number of daily infections to be 1 million. Currently, the number of infections and antimicrobial-resistant strains is rising. A rapid and accurate etiologic diagnosis is critical to solving this problem. In this study, we compared the STI CNM Real-Time PCR Kit using the Xpert® CT/NG technique (Cepheid®, USA) as Gold Standard for the diagnosis of Chlamydia trachomatis and Neisseria gonorrhoeae and EasyNAT® MG (Ustar Biotechnologies (Hangzhou) Ltd., China) as Gold Standard for the diagnosis of Mycoplasma genitalium infection. Regarding C. trachomatis and N. gonorrhoeae, out of 200 samples, there was a match in 199 cases, with only one positive sample not being detected by the STI CNM Real-Time PCR Kit. This results in a sensitivity of 96% and a specificity of 100% for this kit. Diagnosing M. genitalium infection, out of 200 samples, the STI CNM Real-Time PCR Kit correctly detected all negative and positive samples, with 100% agreement compared to the reference technique. In summary, the STI assay has a very high sensitivity and specificity, comparable to other commercial diagnostic kits. Furthermore, it has the advantage of bundling the detection of the three main bacterial agents of urethritis/cervicitis, resulting in better cost efficiency.

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.

The association between non-viral sexually transmitted infections and pregnancy outcome in Latin America and the Caribbean: A systematic review

Introduction

Non-viral sexually transmitted infections are known to be associated with adverse pregnancy outcomes. For these pathogens, standard antenatal screening is not broadly performed in Latin America and the Caribbean. The aim of this study was to comprehensively review the association of non-viral sexually transmitted infections and neonatal outcomes among pregnant women in the region.

Methods

Four databases (PubMed, Embase, SciELO and LILACS) were examined to identify eligible studies published up to September 2022. English or Spanish cross-sectional, case-control and cohort studies assessing the association of non-viral sexually transmitted infections and adverse pregnancy outcomes were evaluated. Articles were firstly screened by means of title and abstract. Potential articles were fully read and assessed for inclusion according to the eligibility criteria. Snowballing search was performed by screening of bibliographies of the chosen potentially relevant papers. Risk of bias within studies was assessed using the Joanna Briggs Institute reviewer's manual.

Results

A selection of 10 out of 9772 search records from five Latin America and the Caribbean countries were included. Six studies associated Treponema pallidum infection with preterm birth (1/6), history of previous spontaneous abortion (2/6), fetal and infant death (1/6), low birth weight (1/6) and funisitis of the umbilical cord (1/6). Three studies associated Chlamydia trachomatis infection with preterm birth (2/3), ectopic pregnancy (1/3) and respiratory symptoms on the newborn (1/3). One study associated Mycoplasma genitalium infection with preterm birth.

Conclusion

This review provides evidence on the association of non-viral sexually transmitted infections with adverse pregnancy outcomes. Further investigation is needed to establish more associations between non-viral sexually transmitted infections and pregnancy outcome, especially for Mycoplasma genitalium, Trichomonas vaginalis and Neisseria gonorrhoeae. Overall, this review calls for more research for public health interventions to promote screening of non-viral sexually transmitted infections during pregnancy, among high-risk population groups of pregnant women living in the region.

Cost-effectiveness analysis of different screening and diagnostic strategies for sexually transmitted infections and bacterial vaginosis in women attending primary health care facilities in Cape Town

Background

Genital inflammation associated with sexually transmitted infections (STIs) and bacterial vaginosis (BV) is considered a key driver in the HIV epidemic. A new rapid point-of-care test (POC) that detects genital inflammation in women-Genital InFlammation Test (GIFT)-was recently developed by researchers at the University of Cape Town. The objective of this study was to establish the cost-effectiveness of this novel intervention relative to other relevant screening and diagnostic strategies for the management of STIs and BV in women seeking care in the public health sector in South Africa.

Methods

A decision analysis model was developed for five different screening and diagnostic strategies for women incorporating syndromic management, screening with GIFT and using etiological diagnosis. A decision tree was constructed using Microsoft Excel Office 365, and cost and effectiveness parameters were obtained from published literature and market prices. The model incorporated all clinic-level and treatment costs associated with diagnosing and treating a single episode of disease. The effectiveness of each approach was proxied by its sensitivity. One-way and threshold sensitivity analyses were conducted to test key uncertainties and assumptions in the model.

Results

Screening with GIFT, and following with antibiotic treatment according to syndromic management guidelines for GIFT-positive cases, was the most cost-effective strategy with an incremental cost-effectiveness ratio (ICER) of USD 11.08 per women diagnosed with an STI(s) and/or BV and provided treatment. This strategy resulted in lower rates of overtreatment compared to syndromic management, but higher rates compared to etiological diagnosis using nucleic acid amplification tests and microscopy. However, following a GIFT positive test with etiological diagnosis prior to treatment did not increase the effectiveness, but dramatically increased the cost.

Conclusion

Screening with GIFT and treating positive cases according to syndromic management guidelines is the most cost-effective strategy for the management of STIs and BV. GIFT has a potential to significantly improve the management of STIs and BV in women by identifying asymptomatic women and reducing their risk of HIV infection. This analysis presents a first step in establishing the cost-effectiveness of these interventions and paves the way for further research to develop optimal context-specific implementation strategies.

Associations of toluidine red unheated serum test response to the treatment of syphilis in pregnancy and congenital syphilis: a 10-year real-world study

BACKGROUND

So far, there is a paucity of real-world data on the syphilis serological responses to the first-line treatment during pregnancy, and there is no relevant study on the necessity of anti-syphilis treatment during pregnancy for those patients who have been treated for syphilis before pregnancy for the prevention of mother-to-child transmission, which might provide valuable insight into treatment effectiveness and optimal management of pregnant women with syphilis.

METHODS

A retrospective study on 10 years of real-world data was performed for accumulative 410 Chinese pregnant women with syphilis. The descriptive statistics were conducted in the study, and toluidine red unheated serum test (TRUST) titer responses to penicillin treatment in syphilis-infected pregnant women, and the associations with congenital syphilis were investigated. We divided the patients into two groups according to the history of anti-syphilis treatment before pregnancy (patients diagnosed with syphilis who had received anti-syphilis treatment before pregnancy, and patients screened and diagnosed with syphilis during pregnancy who had no previous history of anti-syphilis treatment).

RESULTS

The rate of congenital syphilis in this study was 6.2% (25/406). There was no significant difference in the rate of congenital syphilis between patients who received anti-syphilis treatment before pregnancy and those who did not. Secondary syphilis and high baseline serum TRUST titer (≥1:8) in pregnant women were independent risk factors for congenital syphilis.

CONCLUSIONS

For the prevention of congenital syphilis, anti-syphilis treatment during pregnancy for syphilis seropositive pregnant women is needed, regardless of whether the patient has received anti-syphilis treatment before pregnancy, especially for those patients with secondary syphilis or high baseline serum TRUST titer, thus, timely surveillance, early diagnosis to timely treatment, and close syphilis reexamination during posttreatment follow-up, may help to reduce the above-mentioned risk factors for congenital syphilis.

Towards the elimination of cervical cancer in low-income and lower-middle-income countries: modelled evaluation of the effectiveness and cost-effectiveness of point-of-care HPV self-collected screening and treatment in Papua New Guinea

Introduction

WHO has launched updated cervical screening guidelines, including provisions for primary HPV screen-and-treat. Papua New Guinea (PNG) has a high burden of cervical cancer, but no national cervical screening programme. We recently completed the first field trials of a screen-and-treat algorithm using point-of-care self-collected HPV and same-day treatment (hereafter self-collected HPV S&T) and showed this had superior clinical performance and acceptability to visual inspection of the cervix with acetic acid (VIA). We, therefore, evaluated the effectiveness, cost-effectiveness and resource implications of a national cervical screening programme using self-collected HPV S&T compared with VIA in PNG.

Methods

An extensively validated platform (‘Policy1-Cervix’) was calibrated to PNG. A total of 38 strategies were selected for investigation, and these incorporated variations in age ranges and screening frequencies and allowed for the identification of the optimal strategy across a wide range of possibilities. A selection of strategies that were identified as being the most effective and cost-effective were then selected for further investigation for longer-term outcomes and budget impact estimation. In the base case, we assumed primary HPV testing has a sensitivity to cervical intraepithelial neoplasia 2 (CIN2+) + of 91.8% and primary VIA of 51.5% based on our earlier field evaluation combined with evidence from the literature. We conservatively assumed HPV sampling and testing would cost US$18. Costs were estimated from a service provider perspective based on data from local field trials and local consultation.

Results

Self-collected HPV S&T was more effective and more cost-effective than VIA. Either twice or thrice lifetime self-collected HPV S&T would be cost-effective at 0.5× gross domestic product (GDP) per capita (incremental cost-effectiveness ratio: US$460–US$656/life-years saved; 1GDPper-capita: US$2829 or PGK9446 (year 2019)) and could prevent 33 000–42 000 cases and 23 000–29 000 deaths in PNG over the next 50 years, if scale-up reached 70% coverage from 2023.

Conclusion

Self-collected HPV S&T was effective and cost-effective in the high-burden, low-resource setting of PNG, and, if scaled-up rapidly, could prevent over 20 000 deaths over the next 50 years. VIA screening was not effective or cost-effective. These findings support, at a country level, WHO updated cervical screening guidelines and indicate that similar approaches could be appropriate for other low-resource settings.

Point-of-care testing and treatment of sexually transmitted and genital infections during pregnancy in Papua New Guinea (WANTAIM trial): protocol for an economic evaluation alongside a cluster-randomised trial

INTRODUCTION

Left untreated, sexually transmitted and genital infections (henceforth STIs) in pregnancy can lead to serious adverse outcomes for mother and child. Papua New Guinea (PNG) has among the highest prevalence of curable STIs including syphilis, chlamydia, gonorrhoea, trichomoniasis and bacterial vaginosis, and high neonatal mortality rates. Diagnosis and treatment of these STIs in PNG rely on syndromic management. Advances in STI diagnostics through point-of-care (PoC) testing using GeneXpert technology hold promise for resource-constrained countries such as PNG. This paper describes the planned economic evaluation of a cluster-randomised cross-over trial comparing antenatal PoC testing and immediate treatment of curable STIs with standard antenatal care in two provinces in PNG.

METHODS AND ANALYSIS

Cost-effectiveness of the PoC intervention compared with standard antenatal care will be assessed prospectively over the trial period (2017-2021) from societal and provider perspectives. Incremental cost-effectiveness ratios will be calculated for the primary health outcome, a composite measure of the proportion of either preterm birth and/or low birth weight; for life years saved; for disability-adjusted life years averted; and for non-health benefits (financial risk protection and improved health equity). Scenario analyses will be conducted to identify scale-up options, and budget impact analysis will be undertaken to understand short-term financial impacts of intervention adoption on the national budget. Deterministic and probabilistic sensitivity analysis will be conducted to account for uncertainty in key model inputs.

ETHICS AND DISSEMINATION

This study has ethical approval from the Institutional Review Board of the PNG Institute of Medical Research; the Medical Research Advisory Committee of the PNG National Department of Health; the Human Research Ethics Committee of the University of New South Wales; and the Research Ethics Committee of the London School of Hygiene and Tropical Medicine. Findings will be disseminated through national stakeholder meetings, conferences, peer-reviewed publications and policy briefs.

TRIAL REGISTRATION NUMBER

ISRCTN37134032.

Economic evaluation of point-of-care testing and treatment for sexually transmitted and genital infections in pregnancy in low- and middle-income countries: A systematic review

BACKGROUND

Sexually transmitted and genital infections in pregnancy are associated with adverse pregnancy and birth outcomes. Point-of-care tests for these infections facilitate testing and treatment in a single antenatal clinic visit and may reduce the risk of adverse outcomes. Successful implementation and scale-up depends on understanding comparative effectiveness of such programmes and their comparative costs and cost effectiveness. This systematic review synthesises and appraises evidence from economic evaluations of point-of-care testing and treatment for sexually transmitted and genital infections among pregnant women in low- and middle-income countries.

METHODS

Medline, Embase and Web of Science databases were comprehensively searched using pre-determined criteria. Additional literature was identified by searching Google Scholar and the bibliographies of all included studies. Economic evaluations were eligible if they were set in low- and middle-income countries and assessed antenatal point-of-care testing and treatment for syphilis, chlamydia, gonorrhoea, trichomoniasis, and/or bacterial vaginosis. Studies were analysed using narrative synthesis. Methodological and reporting standards were assessed using two published checklists.

RESULTS

Sixteen economic evaluations were included in this review; ten based in Africa, three in Latin and South America and three were cross-continent comparisons. Fifteen studies assessed point-of-care testing and treatment for syphilis, while one evaluated chlamydia. Key drivers of cost and cost-effectiveness included disease prevalence; test, treatment, and staff costs; test sensitivity and specificity; and screening and treatment coverage. All studies met 75% or more of the criteria of the Drummond Checklist and 60% of the Consolidated Health Economics Evaluation Reporting Standards.

CONCLUSIONS

Generally, point-of-care testing and treatment was cost-effective compared to no screening, syndromic management, and laboratory-based testing. Future economic evaluations should consider other common infections, and their lifetime impact on mothers and babies. Complementary affordability and equity analyses would strengthen the case for greater investment in antenatal point-of-care testing and treatment for sexually transmitted and genital infections.

Lactobacillus rhamnosus and Lactobacillus casei Affect Various Stages of Gardnerella Species Biofilm Formation

Bacterial vaginosis (BV) and its recurrence are most commonly associated with the formation of Gardnerella species biofilm. Probiotics are typically used to treat BV; however, the optimal period of Lactobacillus probiotic application in BV treatment remains uncertain. The present study aimed to explore the effects of Lactobacillus rhamnosus and Lactobacillus casei on various stages of biofilm formation in Gardnerella species. The biofilm-forming ability of seven strains, including one Gardnerella vaginalis ATCC 14018 and six clinically isolated Gardnerella species, was determined via gentian violet staining assay. Moreover, the sensitivity of the planktonic and biofilm forms toward metronidazole and clindamycin was assessed via microdilution broth method. L. rhamnosus Xbb-LR-1 and L. casei Xbb-LC-1 were added during various stages of biofilm formation in Gardnerella species and were cocultured for 24 h. The biofilm thickness of each sample was determined via confocal laser scanning microscopy (CLSM). The absolute quantities of Gardnerella species in each sample was obtained via real time polymerase chain reaction method, and the pH value was obtained using a pH indicator paper. Biofilm formation by Gardnerella species in a medium with distinct pH values was observed via gentian violet staining, CLSM, and scanning electron microscopy (SEM). The biofilm increased the resistance of Gardnerella species toward metronidazole and clindamycin. L. rhamnosus added at the initial biofilm formation stage in Gardnerella species exhibited highest inhibitory effect, with a percentage inhibition of 38.17% ± 1.35%. When the pH value of the culture medium was <4.5 or >6.5, ATCC 14018 could hardly form a biofilm; however, at pH ≥4.5 and ≤6.5, it was able to form a stronger biofilm. The amount of biofilm attained maximum value at optical density of 3.29 ± 0.28 (595 nm), pH 5.5, and at 36 h. Biofilm formation increases the resistance of Gardnerella species toward antibiotics. Maintaining an acidic vaginal environment with pH <4.5 and a vaginal microbiota dominated by Lactobacillus remarkably prevents the formation of Gardnerella species biofilm at the initial stage, which further has a significant impact on the treatment and prevention of biofilm-related infections.

Treatment evaluation to improve preventing mother to child transmission among women with syphilis

The aim of this study was to evaluate the effectiveness of preventing mother to child syphilis transmission to improve pregnancy outcomes. We performed a retrospective analysis of municipal databases of mother-to-child syphilis transmission. Pregnant women with syphilis were included. Group specific pregnancy outcomes were analyzed according to treatment. A total of 28 pregnant women were diagnosed with syphilis in 2012; 321 were diagnosed with syphilis in 2018. A prevalence of 0.14% was observed amongst pregnant women in Suzhou city from 2012–2018. Primary treatments included benzathine penicillin, ceftriaxone sodium or erythromycin when patients were allergic to Benzathine penicillin. The treatment coverage was 81.57%, and only 52.86% of pregnant women were adequately treated. Adverse pregnant outcomes were higher amongst untreated women. Expanding early screening coverage and promoting treatment were key to improving pregnancy outcomes amongst women with syphilis.