Ignored and undervalued in public health: a systematic review of health state utility values associated with syphilis infection.

BACKGROUND: Syphilis is a sexually transmitted infection causing significant global morbidity and mortality. To inform policymaking and economic evaluation studies for syphilis, we summarised utility and disability weights for health states associated with syphilis. METHODS: We conducted a systematic review, searching six databases for economic evaluations and primary valuation studies related to syphilis from January 2000 to February 2022. We extracted health state utility values or disability weights, including identification of how these were derived. The study was registered in the international prospective register of systematic reviews (PROSPERO, CRD42021230035). FINDINGS: Of 3401 studies screened, 22 economic evaluations, two primary studies providing condition-specific measures, and 13 burden of disease studies were included. Fifteen economic evaluations reported outcomes as disability-adjusted life years (DALYs) and seven reported quality-adjusted life years (QALYs). Fourteen of 15 economic evaluations that used DALYS based their values on the original Global Burden of Disease (GBD) study from 1990 (published in 1996). For the seven QALY-related economic evaluations, the methodology varied between studies, with some studies using assumptions and others creating utility weights or converting them from disability weights. INTERPRETATION: We found a limited evidence base for the valuation of health states for syphilis, a lack of transparency for the development of existing health state utility values, and inconsistencies in the application of these values to estimate DALYs and QALYs. Further research is required to expand the evidence base so that policymakers can access accurate and well-informed economic evaluations to allocate resources to address syphilis and implement syphilis programs that are cost-effective.

New HIV Infections Among Key Populations and Their Partners in 2010 and 2022, by World Region: A Multisources Estimation.

BACKGROUND: Previously, The Joint United Nations Programme on HIV/AIDS estimated proportions of adult new HIV infections among key populations (KPs) in the last calendar year, globally and in 8 regions. We refined and updated these, for 2010 and 2022, using country-level trend models informed by national data. METHODS: Infections among 15-49 year olds were estimated for sex workers (SWs), male clients of female SW, men who have sex with men (MSM), people who inject drugs (PWID), transgender women (TGW), and non-KP sex partners of these groups. Transmission models used were Goals (71 countries), AIDS Epidemic Model (13 Asian countries), Optima (9 European and Central Asian countries), and Thembisa (South Africa). Statistical Estimation and Projection Package fits were used for 15 countries. For 40 countries, new infections in 1 or more KPs were approximated from first-time diagnoses by the mode of transmission. Infection proportions among nonclient partners came from Goals, Optima, AIDS Epidemic Model, and Thembisa. For remaining countries and groups not represented in models, median proportions by KP were extrapolated from countries modeled within the same region. RESULTS: Across 172 countries, estimated proportions of new adult infections in 2010 and 2022 were both 7.7% for SW, 11% and 20% for MSM, 0.72% and 1.1% for TGW, 6.8% and 8.0% for PWID, 12% and 10% for clients, and 5.3% and 8.2% for nonclient partners. In sub-Saharan Africa, proportions of new HIV infections decreased among SW, clients, and non-KP partners but increased for PWID; elsewhere these groups' 2010-to-2022 differences were opposite. For MSM and TGW, the proportions increased across all regions. CONCLUSIONS: KPs continue to have disproportionately high HIV incidence.

Prevalence of syphilis among men who have sex with men: a global systematic review and meta-analysis from 2000-20.

BACKGROUND: The WHO Global Health Sector Strategy aims to reduce worldwide syphilis incidence by 90% between 2018 and 2030. If this goal is to be achieved, interventions that target high-burden groups, including men who have sex with men (MSM), will be required. However, there are no global prevalence estimates of syphilis among MSM to serve as a baseline for monitoring or modelling disease burden. We aimed to assess the global prevalence of syphilis among MSM using the available literature. METHODS: In this global systematic review and meta-analysis, we searched MEDLINE, Embase, LILACS, and AIM databases, and Integrated Bio-Behavioral Surveillance (IBBS) reports between April 23, 2019, and Feb 1, 2020, to identify studies done between Jan 1, 2000, and Feb 1, 2020, with syphilis point prevalence data measured by biological assay among MSM (defined as people who were assigned as male at birth and had oral or anal sex with at least one other man in their lifetime). Studies were excluded if participants were exclusively HIV-infected MSM, injection-drug users, only seeking care for sexually transmitted infections (STIs) or genital symptoms, or routine STI clinic attendees. Data were extracted onto standardised forms and cross-checked for accuracy and validity. We used random-effects models to generate pooled prevalence estimates across the eight regions of the Sustainable Development Goals. We calculated risk of study bias based on the Appraisal tool for Cross-Sectional Studies, and stratified results based on low versus high risk of bias. This systematic review and meta-analysis was registered with PROSPERO, CRD42019144594. FINDINGS: We reviewed 4339 records, 228 IBBS reports, and ten articles from other sources. Of these, 1301 duplicate records were excluded, 2467 records were excluded after title and abstract screening, and 534 articles were excluded after full-text analysis. We identified 345 prevalence data points from 275 studies across 77 countries, with a total of 606 232 participants. Global pooled prevalence from 2000-20 was 7·5% (95% CI 7·0-8·0%), ranging from 1·9% (1·0-3·1%) in Australia and New Zealand to 10·6% (8·5-12·9%) in Latin America and the Caribbean. INTERPRETATION: Unacceptably high syphilis prevalence among MSM warrants urgent action. FUNDING: Wellcome Trust.

The impact of the program for medical male circumcision on HIV in South Africa: analysis using three epidemiological models.

Background: South Africa began offering medical male circumcision (MMC) in 2010. We evaluated the current and future impact of this program to see if it is effective in preventing new HIV infections. Methods: The Thembisa, Goals and Epidemiological Modeling Software (EMOD) HIV transmission models were calibrated to South Africa's HIV epidemic, fitting to household survey data on HIV prevalence, risk behaviors, and proportions of men circumcised, and to programmatic data on intervention roll-out including program-reported MMCs over 2009-2017. We compared the actual program accomplishments through 2017 and program targets through 2021 with a counterfactual scenario of no MMC program. Results: The MMC program averted 71,000-83,000 new HIV infections from 2010 to 2017. The future benefit of the circumcision already conducted will grow to 496,000-518,000 infections (6-7% of all new infections) by 2030. If program targets are met by 2021 the benefits will increase to 723,000-760,000 infections averted by 2030. The cost would be $1,070-1,220 per infection averted relative to no MMC. The savings from averted treatment needs would become larger than the costs of the MMC program around 2034-2039. In the Thembisa model, when modelling South Africa's 9 provinces individually, the 9-provinces-aggregate results were similar to those of the single national model. Across provinces, projected long-term impacts were largest in Free State, KwaZulu-Natal and Mpumalanga (23-27% reduction over 2017-2030), reflecting these provinces' greater MMC scale-up. Conclusions: MMC has already had a modest impact on HIV incidence in South Africa and can substantially impact South Africa's HIV epidemic in the coming years.

Prevalence of syphilis, gonorrhoea and chlamydia in women in Fiji, the Federated States of Micronesia, Papua New Guinea and Samoa, 1995-2017: Spectrum-STI model estimates.

OBJECTIVE: To estimate prevalence levels of and time trends for active syphilis, gonorrhoea and chlamydia in women aged 15-49 years in four countries in the Pacific (Fiji, the Federated States of Micronesia [FSM], Papua New Guinea [PNG] and Samoa) to inform surveillance and control strategies for sexually transmitted infections (STIs). METHODS: The Spectrum-STI model was fitted to data from prevalence surveys and screenings of adult female populations collected during 1995-2017 and adjusted for diagnostic test performance and to account for undersampled high-risk populations. For chlamydia and gonorrhoea, data were further adjusted for age and differences between urban and rural areas. RESULTS: Prevalence levels were estimated as a percentage (95% confidence interval). In 2017, active syphilis prevalence was estimated in Fiji at 3.89% (2.82 to 5.06), in FSM at 1.48% (0.93 to 2.16), in PNG at 3.91% (1.67 to 7.24) and in Samoa at 0.16% (0.07 to 0.37). For gonorrhoea, the prevalence in Fiji was 1.63% (0.50 to 3.87); in FSM it was 1.59% (0.49 to 3.58); in PNG it was 11.0% (7.25 to 16.1); and in Samoa it was 1.61% (1.17 to 2.19). The prevalence of chlamydia in Fiji was 24.1% (16.5 to 32.7); in FSM it was 23.9% (18.5 to 30.6); in PNG it was 14.8% (7.39 to 24.7); and in Samoa it was 30.6% (26.8 to 35.0). For each specific disease within each country, the 95% confidence intervals overlapped for 2000 and 2017, although in PNG the 2017 estimates for all three STIs were below the 2000 estimates. These patterns were robust in the sensitivity analyses. DISCUSSION: This study demonstrated a persistently high prevalence of three major bacterial STIs across four countries in WHO's Western Pacific Region during nearly two decades. Further strengthening of strategies to control and prevent STIs is warranted.

The Spectrum-STI Groups model: syphilis prevalence trends across high-risk and lower-risk populations in Yunnan, China.

The Spectrum-STI model, structured by sub-groups within a population, was used in a workshop in Yunnan, China, to estimate provincial trends in active syphilis in 15 to 49-year-old adults. Syphilis prevalence data from female sex workers (FSW), men who have sex with men (MSM), and lower-risk women and men in Yunnan were identified through literature searches and local experts. Sources included antenatal care clinic screening, blood donor screening, HIV/STI bio-behavioural surveys, sentinel surveillance, and epidemiology studies. The 2017 provincial syphilis prevalence estimates were 0.26% (95% confidence interval 0.17-0.34%) in women and 0.28% (0.20-0.36%) in men. Estimated prevalence was 6.8-fold higher in FSW (1.69% (0.68-3.97%) than in lower-risk women (0.25% (0.18-0.35%)), and 22.7-fold higher in MSM (5.35% (2.74-12.47%) than in lower-risk men (0.24% (0.17-0.31%). For all populations, the 2017 estimates were below the 2005 estimates, but differences were not significant. In 2017 FSW and MSM together accounted for 9.3% of prevalent cases. These estimates suggest Yunnan's STI programs have kept the overall prevalence of syphilis low, but prevalence remains high in FSW and MSM. Strengthening efforts targeting FSW and MSM, and identification of other risk populations e.g. among heterosexual men, are critical to reduce syphilis.

Correction: Global burden of maternal and congenital syphilis and associated adverse birth outcomes-Estimates for 2016 and progress since 2012.

[This corrects the article DOI: 10.1371/journal.pone.0211720.].

Global burden of maternal and congenital syphilis and associated adverse birth outcomes-Estimates for 2016 and progress since 2012.

BACKGROUND: In 2007 the World Health Organization (WHO) launched the global initiative to eliminate mother-to-child transmission of syphilis (congenital syphilis, or CS). To assess progress towards the goal of <50 CS cases per 100,000 live births, we generated regional and global estimates of maternal and congenital syphilis for 2016 and updated the 2012 estimates. METHODS: Maternal syphilis estimates were generated using the Spectrum-STI model, fitted to sentinel surveys and routine testing of pregnant women during antenatal care (ANC) and other representative population data. Global and regional estimates of CS used the same approach as previous WHO estimates. RESULTS: The estimated global maternal syphilis prevalence in 2016 was 0.69% (95% confidence interval: 0.57-0.81%) resulting in a global CS rate of 473 (385-561) per 100,000 live births and 661,000 (538,000-784,000) total CS cases, including 355,000 (290,000-419,000) adverse birth outcomes (ABO) and 306,000 (249,000-363,000) non-clinical CS cases (infants without clinical signs born to un-treated mothers). The ABOs included 143,000 early fetal deaths and stillbirths, 61,000 neonatal deaths, 41,000 preterm or low-birth weight births, and 109,000 infants with clinical CS. Of these ABOs- 203,000 (57%) occurred in pregnant women attending ANC but not screened for syphilis; 74,000 (21%) in mothers not enrolled in ANC, 55,000 (16%) in mothers screened but not treated, and 23,000 (6%) in mothers enrolled, screened and treated. The revised 2012 estimates were 0.70% (95% CI: 0.63-0.77%) maternal prevalence, and 748,000 CS cases (539 per 100,000 live births) including 397,000 (361,000-432,000) ABOs. The estimated decrease in CS case rates between 2012 and 2016 reflected increased access to ANC and to syphilis screening and treatment. CONCLUSIONS: Congenital syphilis decreased worldwide between 2012 and 2016, although maternal prevalence was stable. Achieving global CS elimination, however, will require improving access to early syphilis screening and treatment in ANC, clinically monitoring all women diagnosed with syphilis and their infants, improving partner management, and reducing syphilis prevalence in the general population by expanding testing, treatment and partner referral beyond ANC.

Adult gonorrhea, chlamydia and syphilis prevalence, incidence, treatment and syndromic case reporting in South Africa: Estimates using the Spectrum-STI model, 1990-2017.

OBJECTIVES: To estimate trends in prevalence and incidence of syphilis, gonorrhea and chlamydia in adult men and women in South Africa. METHODS: The Spectrum-STI tool estimated trends in prevalence and incidence of active syphilis, gonorrhea and chlamydia, fitting South African prevalence data. Results were used, alongside programmatic surveillance data, to estimate trends in incident gonorrhea cases resistant to first-line treatment, and the reporting gap of symptomatic male gonorrhea and chlamydia cases treated but not reported as cases of urethritis syndrome. RESULTS: In 2017 adult (15-49 years) the estimated female and male prevalences for syphilis were 0.50% (95% CI: 0.32-0.80%) and 0.97% (0.19-2.28%), for gonorrhea 6.6% (3.8-10.8%) and 3.5% (1.7-6.1%), and for chlamydia 14.7% (9.9-21%) and 6.0% (3.8-10.4%), respectively. Between 1990 and 2017 the estimated prevalence of syphilis declined steadily in women and men, probably in part reflecting improved treatment coverage. For gonorrhea and chlamydia, estimated prevalence and incidence showed no consistent time trend in either women or men. Despite growing annual numbers of gonorrhea cases - reflecting population growth - the estimated number of first line treatment-resistant gonorrhea cases did not increase between 2008 and 2017, owing to changes in first-line antimicrobial treatment regimens for gonorrhea in 2008 and 2014/5. Case reporting completeness among treated male urethritis syndrome episodes was estimated at 10-28% in 2017. CONCLUSION: South Africa continues to suffer a high STI burden. Improvements in access and quality of maternal, STI and HIV health care services likely contributed to the decline in syphilis prevalence. The lack of any decline in gonorrhea and chlamydia prevalence highlights the need to enhance STI services beyond clinic-based syndromic case management, to reinvigorate primary STI and HIV prevention and, especially for women, to screen for asymptomatic infections.

Prevalence and incidence estimates for syphilis, chlamydia, gonorrhea, and congenital syphilis in Colombia, 1995–2016

[ABSTRACT]. Objectives. To estimate adult (15–49 years old) prevalence and incidence of active syphilis, gonorrhea, and chlamydia, and incidence of congenital syphilis (CS) and adverse birth outcomes (ABOs) in Colombia, over 1995–2016. Methods. The Spectrum-STI epidemiological model tool estimated gonorrhea and chlamydia prevalences as moving averages across prevalences observed in representative general population surveys. For adult syphilis, Spectrum-STI applied segmented polynomial regression through prevalence data from antenatal care (ANC) surveys, routine ANC-based screening, and general population surveys. CS cases and ABOs were estimated from Spectrum’s maternal syphilis estimates and proportions of women screened and treated for syphilis, applying World Health Organization case definitions and risk probabilities. Results. The Spectrum model estimated prevalences in 2016 of 0.70% (95% confidence interval (CI): 0.15%-1.9%) in women and 0.60% (0.1%-1.9%) in men for gonorrhea and of 9.2% (4.4%-15.4%) in women and 7.4% (3.5%-14.7%) in men for chlamydia, without evidence for trends over 1995–2016. The prevalence of active syphilis in 2016 was 1.25% (1.22–1.29%) in women and 1.25% (1.1%-1.4%) in men, decreasing from 2.6% (2.1%-3.2%) in women in 1995. Corresponding CS cases in 2016 (including cases without clinical symptoms) totaled 3 851, of which 2 245 were ABOs. Annual CS and ABO estimates decreased over 2008–2016, reflecting decreasing maternal prevalence and increasing cases averted through ANC-based screening and treatment. Conclusions. The available surveillance and monitoring data synthesized in Spectrum-STI—and the resulting first-ever national STI estimates for Colombia—highlighted Colombia’s persistently high STI burden. Adult syphilis and congenital syphilis are estimated to be falling, reflecting improving screening efforts. Strengthened surveillance, including with periodic screening in low-risk populations and future refined Spectrum estimations, should support planning and implementation of STI prevention and control, including CS elimination.

[RESUMEN]. Objetivos. Estimar la prevalencia e incidencia en los adultos (de 15 a 49 años de edad) de sífilis activa, gonorrea y clamidiasis, así como la incidencia de sífilis congénita y resultados adversos del embarazo en Colombia durante el período de 1995 al 2016. Métodos. Usando las herramientas del modelo epidemiológico Spectrum-STI se estimó la prevalencia de gonorrea y clamidiasis como promedios móviles entre las distintas prevalencias observadas en encuestas representativas de la población general. En cuanto a la sífilis en los adultos, Spectrum-STI aplicó la regresión polinomial segmentada a los datos sobre prevalencia recopilados en encuestas de atención prenatal, el tamizaje sistemático en la atención prenatal y encuestas a la población general. Los casos de sífilis congénita y de resultados adversos del embarazo se estimaron a partir de las cifras de Spectrum sobre sífilis materna y proporciones de mujeres examinadas y tratadas por sífilis, aplicando las definiciones de casos y probabilidades de riesgo de la Organización Mundial de la Salud. Resultados. El modelo Spectrum estimó que en el 2016 la prevalencia de la gonorrea fue de 0,70% (intervalo de confianza de 95% [IC]: 0,15%-1,9%) en las mujeres y de 0,60% (0,1%-1,9%) en los hombres, y que la prevalencia de la clamidiasis fue de 9,2% (4,4%-15,4%) en las mujeres y de 7,4% (3,5%-14,7%) en los hombres, sin datos científicos acerca de las tendencias durante el período 1995-2016. La prevalencia de la sífilis activa en el 2016 fue de 1,25% (1,22-1,29%) en las mujeres y de 1,25% (1,1%-1,4%) en los hombres, con una reducción de 2,6% (2,1%-3,2%) en las mujeres con respecto a 1995. Los casos correspondientes de sífilis congénita en el 2016 (incluidos los asintomáticos) sumaron en total 3 851, de los cuales 2 245 fueron resultados adversos del embarazo. Las cifras anuales estimadas de sífilis congénita y resultados adversos del embarazo disminuyeron entre el 2008 y el 2016, lo que reflejó un descenso en la prevalencia materna y un aumento de casos evitados mediante el tamizaje y el tratamiento durante la atención prenatal. Conclusiones. Los datos disponibles sobre vigilancia y seguimiento sintetizados en Spectrum‑STI, así como los consiguientes estimados nacionales de infecciones de transmisión sexual (ITS) hechos por primera vez en Colombia, pusieron de relieve la carga de morbilidad por ITS persistentemente alta en ese país. Se estima que la sífilis en los adultos y la sífilis congénita van en descenso, lo que refleja mejoras en las actividades de tamizaje. Un fortalecimiento de la vigilancia, incluso con tamizaje periódico en las poblaciones de bajo riesgo, y estimaciones más refinadas con Spectrum en el futuro deberían brindar apoyo a la planificación y la ejecución de medidas para la prevención y el control de las infecciones de transmisión sexual, incluida la eliminación de la sífilis congénita.

[RESUMO]. Objetivos. Estimar a incidência e a prevalência na população adulta (com idade de 15–49 anos) de sífilis ativa, gonorreia e clamídia e a incidência de sífilis congênita (SC) e desfechos adversos congênitos na Colômbia no período de 1995 a 2016. Métodos. O modelo epidemiológico Spectrum-STI foi o instrumento usado para estimar a prevalência de gonorreia e clamídia como médias móveis nas prevalências observadas em pesquisas representativas da população geral. A sífilis em adultos foi estimada com a regressão polinomial segmentada aplicada ao modelo Spectrum-STI com dados de prevalência obtidos de pesquisas da atenção pré-natal, exames pré-natais de rotina de detecção precoce e pesquisas da população geral. Casos de SC e desfechos adversos congênitos foram estimados a partir das estimativas de sífilis materna do modelo Spectrum e percentuais de mulheres que fizeram testes de detecção e foram tratadas para sífilis, segundo as definições de casos da Organização Mundial da Saúde (OMS) e probabilidades de risco. Resultados. O modelo Spectrum estimou, para 2016, uma prevalência de gonorreia de 0,70% (intervalo de confiança de 95% [IC 95%] 0,15%–1,9%) no sexo feminino e 0,60% (0,1%–1,9%) no sexo masculino e uma prevalência de clamídia de 9,2% (4,4%–15,4%) no sexo feminino e 7,4% (3,5%–14.7%) no sexo masculino, sem evidência de tendências no período 1995–2016. A prevalência de sífilis ativa em 2016 foi de 1,25% (1,22–1,29%) no sexo feminino e 1,25% (1,1%–1,4%) no sexo masculino, demonstrando um declínio da prevalência de 2,6% (2,1%–3,2%) observada em 1995 para o sexo feminino. Houve, ao todo, 3.851 casos correspondentes de SC em 2016 (incluindo casos assintomáticos), dos quais 2.245 foram desfechos adversos congênitos. Observou-se uma redução nas estimativas anuais de SC e desfechos adversos congênitos em 2008–2016, refletindo a diminuição da prevalência materna e o número crescente de casos evitados com exames pré-natais de detecção e tratamento. Conclusões. Os dados disponíveis de vigilância e monitoramento condensados no modelo Spectrum-STI, e as resultantes estimativas nacionais de infeções sexualmente transmissíveis (IST) obtidas pela primeira vez na Colômbia, evidenciam a alta carga persistente de IST no país. Estima-se que a ocorrência de sífilis do adulto e sífilis congénita esteja diminuindo em decorrência da melhoria nos esforços de detecção precoce. A vigilância reforçada, consistindo também de exames periódicos de detecção precoce nas populações de baixo risco e estimavas futuras aprimoradas do instrumento Spectrum, deve sustentar o planejamento e a implementação de controle e prevenção de IST e a eliminação da SC.

Syphilis prevalence trends in adult women in 132 countries - estimations using the Spectrum Sexually Transmitted Infections model.

We estimated national-level trends in the prevalence of probable active syphilis in adult women using the Spectrum Sexually Transmitted Infections (STI) model to inform program planning, target-setting, and progress evaluation in STI control. The model fitted smoothed-splines polynomial regressions to data from antenatal clinic surveys and screening and representative household surveys, adjusted for diagnostic test performance and weighted by national coverage. Eligible countries had ≥1 data point from 2010 or later and ≥3 from 2000 or later from adult populations considered representative of the general female population (pregnant women or community-based studies). Between 2012 and 2016, the prevalence of probable active syphilis in women decreased in 54 (41%) of 132 eligible countries; this decrease was substantive (≥10% proportionally, ≥0.10% percentage-point absolute difference and non-overlapping 95% confidence intervals in 2012 and 2016) in 5 countries. Restricting eligible data to prevalence measurements of dual treponemal and non-treponemal testing limited estimates to 85 countries; of these, 45 countries (53%) showed a decrease. These standardized trend estimates highlight the need for increased investment in national syphilis surveillance and control efforts if the World Health Organization target of a 90% reduction in the incidence of syphilis between 2018 and 2030 is to be met.

The emerging health impact of voluntary medical male circumcision in Zimbabwe: An evaluation using three epidemiological models.

BACKGROUND: Zimbabwe adopted voluntary medical male circumcision (VMMC) as a priority HIV prevention strategy in 2007 and began implementation in 2009. We evaluated the costs and impact of this VMMC program to date and in future. METHODS: Three mathematical models describing Zimbabwe's HIV epidemic and program evolution were calibrated to household survey data on prevalence and risk behaviors, with circumcision coverage calibrated to program-reported VMMCs. We compared trends in new infections and costs to a counterfactual without VMMC. Input assumptions were agreed in workshops with national stakeholders in 2015 and 2017. RESULTS: The VMMC program averted 2,600-12,200 infections (among men and women combined) by the end of 2016. This impact will grow as circumcised men are protected lifelong, and onward dynamic transmission effects, which protect women via reduced incidence and prevalence in their male partners, increase over time. If other prevention interventions remain at 2016 coverages, the VMMCs already performed will avert 24,400-69,800 infections (2.3-5% of all new infections) through 2030. If coverage targets are achieved by 2021 and maintained, the program will avert 108,000-171,000 infections (10-13% of all new infections) by 2030, costing $2,100-3,250 per infection averted relative to no VMMC. Annual savings from averted treatment needs will outweigh VMMC maintenance costs once coverage targets are reached. If Zimbabwe also achieves ambitious UNAIDS targets for scaling up treatment and prevention efforts, VMMC will reduce the HIV incidence remaining at 2030 by one-third, critically contributing to the UNAIDS goal of 90% incidence reduction. CONCLUSIONS: VMMC can substantially impact Zimbabwe's HIV epidemic in the coming years; this investment will save costs in the longer term.

Prevalence and incidence estimates for syphilis, chlamydia, gonorrhea, and congenital syphilis in Colombia, 1995-2016.

OBJECTIVES: To estimate adult (15-49 years old) prevalence and incidence of active syphilis, gonorrhea, and chlamydia, and incidence of congenital syphilis (CS) and adverse birth outcomes (ABOs) in Colombia, over 1995-2016. METHODS: The Spectrum-STI epidemiological model tool estimated gonorrhea and chlamydia prevalences as moving averages across prevalences observed in representative general population surveys. For adult syphilis, Spectrum-STI applied segmented polynomial regression through prevalence data from antenatal care (ANC) surveys, routine ANC-based screening, and general population surveys. CS cases and ABOs were estimated from Spectrum's maternal syphilis estimates and proportions of women screened and treated for syphilis, applying World Health Organization case definitions and risk probabilities. RESULTS: The Spectrum model estimated prevalences in 2016 of 0.70% (95% confidence interval (CI): 0.15%-1.9%) in women and 0.60% (0.1%-1.9%) in men for gonorrhea and of 9.2% (4.4%-15.4%) in women and 7.4% (3.5%-14.7%) in men for chlamydia, without evidence for trends over 1995-2016. The prevalence of active syphilis in 2016 was 1.25% (1.22-1.29%) in women and 1.25% (1.1%-1.4%) in men, decreasing from 2.6% (2.1%-3.2%) in women in 1995. Corresponding CS cases in 2016 (including cases without clinical symptoms) totaled 3 851, of which 2 245 were ABOs. Annual CS and ABO estimates decreased over 2008-2016, reflecting decreasing maternal prevalence and increasing cases averted through ANC-based screening and treatment. CONCLUSIONS: The available surveillance and monitoring data synthesized in Spectrum-STI- and the resulting first-ever national STI estimates for Colombia-highlighted Colombia's persistently high STI burden. Adult syphilis and congenital syphilis are estimated to be falling, reflecting improving screening efforts. Strengthened surveillance, including with periodic screening in low-risk populations and future refined Spectrum estimations, should support planning and implementation of STI prevention and control, including CS elimination.

Adult female syphilis prevalence, congenital syphilis case incidence and adverse birth outcomes, Mongolia 2000-2016: Estimates using the Spectrum STI tool.

INTRODUCTION: Mongolia's health ministry prioritizes control of Sexually Transmitted Infections, including syphilis screening and treatment in antenatal care (ANC). METHODS: Adult syphilis prevalence trends were fitted using the Spectrum-STI estimation tool, using data from ANC surveys and routine screening over 1997-2016. Estimates were combined with programmatic data to estimate numbers of treated and untreated pregnant women with syphilis and associated incidence congenital syphilis (CS) and CS-attributable adverse birth outcomes (ABO), which we compared with CS case reports. RESULTS: Syphilis prevalence in pregnant women was estimated at 1.7% in 2000 and 3.0% in 2016. We estimated 652 CS cases, of which 410 ABO, in 2016. Far larger, annually increasing numbers of CS cases and ABO were estimated to have been prevented: 1654 cases, of which 789 ABO in 2016 - thanks to increasing coverages of ANC (99% in 2016), ANC-based screening (97% in 2016) and treatment of women diagnosed (81% in 2016). The 42 CS cases reported nationally over 2016 (liveborn infants only) represented 27% of liveborn infants with clinical CS, but only 7% of estimated CS cases among women found syphilis-infected in ANC, and 6% of all estimated CS cases including those born to women with undiagnosed syphilis. DISCUSSION/CONCLUSION: Mongolia's ANC-based syphilis screening program is reducing CS, but maternal prevalence remains high. To eliminate CS (target: <50 cases per 100,000 live births), Mongolia should strengthen ANC services, limiting losses during referral for treatment, and under-diagnosis of CS including still-births and neonatal deaths, and expand syphilis screening and prevention programs.

Trends and Predictors of Syphilis Prevalence in the General Population: Global Pooled Analyses of 1103 Prevalence Measures Including 136 Million Syphilis Tests.

Background: This study assessed levels, trends, and associations of observed syphilis prevalence in the general adult population using global pooled analyses. Methods: A standardized database of syphilis prevalence was compiled by pooling systematically gathered data. Random-effects meta-analyses and meta-regressions were conducted using data from the period 1990-2016 to estimate pooled measures and assess predictors and trends. Countries were classified by World Health Organization region. Sensitivity analyses were conducted. Results: The database included 1103 prevalence measures from 136 million syphilis tests across 154 countries (85% from women in antenatal care). Global pooled mean prevalence (weighted by region population size) was 1.11% (95% confidence interval [CI], .99-1.22). Prevalence predictors were region, diagnostic assay, sample size, and calendar year interacting with region. Compared to the African Region, the adjusted odds ratio (AOR) was 0.42 (95% CI, .33-.54) for the Region of the Americas, 0.13 (95% CI, .09-.19) for the Eastern Mediterranean Region, 0.05 (95% CI, .03-.07) for the European Region, 0.21 (95% CI, .16-.28) for the South-East Asia Region, and 0.41 (95% CI, .32-.53) for the Western Pacific Region. Treponema pallidum hemagglutination assay (TPHA) only or rapid plasma reagin (RPR) only, compared with dual RPR/TPHA diagnosis, produced higher prevalence (AOR >1.26), as did smaller sample-size studies (<500 persons) (AOR >2.16). Prevalence declined in all regions; the annual AORs ranged from 0.84 (95% CI, .79-.90) in the Eastern Mediterranean to 0.97 (95% CI, .97-1.01) in the Western Pacific. The pooled mean male-to-female prevalence ratio was 1.00 (95% CI, .89-1.13). Sensitivity analyses confirmed robustness of results. Conclusions: Syphilis prevalence has declined globally over the past 3 decades. Large differences in prevalence persist among regions, with the African Region consistently the most affected.

Prevalence and incidence estimates for syphilis, chlamydia, gonorrhea, and congenital syphilis in Colombia, 1995-2016 / Estimaciones sobre la prevalencia y la incidencia de sífilis, clamidiasis, gonorrea y sífilis congénita en Colombia, 1995-2016 / Estimativas da incidência e prevalência de sífilis, clamídia, gonorreia e sífilis congênita na Colômbia, 1995-2016

ABSTRACT Objectives To estimate adult (15-49 years old) prevalence and incidence of active syphilis, gonorrhea, and chlamydia, and incidence of congenital syphilis (CS) and adverse birth outcomes (ABOs) in Colombia, over 1995-2016. Methods The Spectrum-STI epidemiological model tool estimated gonorrhea and chlamydia prevalences as moving averages across prevalences observed in representative general population surveys. For adult syphilis, Spectrum-STI applied segmented polynomial regression through prevalence data from antenatal care (ANC) surveys, routine ANC-based screening, and general population surveys. CS cases and ABOs were estimated from Spectrum's maternal syphilis estimates and proportions of women screened and treated for syphilis, applying World Health Organization case definitions and risk probabilities. Results The Spectrum model estimated prevalences in 2016 of 0.70% (95% confidence interval (CI): 0.15%-1.9%) in women and 0.60% (0.1%-1.9%) in men for gonorrhea and of 9.2% (4.4%-15.4%) in women and 7.4% (3.5%-14.7%) in men for chlamydia, without evidence for trends over 1995-2016. The prevalence of active syphilis in 2016 was 1.25% (1.22-1.29%) in women and 1.25% (1.1%-1.4%) in men, decreasing from 2.6% (2.1%-3.2%) in women in 1995. Corresponding CS cases in 2016 (including cases without clinical symptoms) totaled 3 851, of which 2 245 were ABOs. Annual CS and ABO estimates decreased over 2008-2016, reflecting decreasing maternal prevalence and increasing cases averted through ANC-based screening and treatment. Conclusions The available surveillance and monitoring data synthesized in Spectrum-STI— and the resulting first-ever national STI estimates for Colombia—highlighted Colombia's persistently high STI burden. Adult syphilis and congenital syphilis are estimated to be falling, reflecting improving screening efforts. Strengthened surveillance, including with periodic screening in low-risk populations and future refined Spectrum estimations, should support planning and implementation of STI prevention and control, including CS elimination.

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RESUMO Objetivos Estimar a incidência e a prevalência na população adulta (com idade de 15-49 anos) de sífilis ativa, gonorreia e clamídia e a incidência de sífilis congênita (SC) e desfechos adversos congênitos na Colômbia no período de 1995 a 2016. Métodos O modelo epidemiológico Spectrum-STI foi o instrumento usado para estimar a prevalência de gonorreia e clamídia como médias móveis nas prevalências observadas em pesquisas representativas da população geral. A sífilis em adultos foi estimada com a regressão polinomial segmentada aplicada ao modelo Spectrum-STI com dados de prevalência obtidos de pesquisas da atenção pré-natal, exames pré-natais de rotina de detecção precoce e pesquisas da população geral. Casos de SC e desfechos adversos congênitos foram estimados a partir das estimativas de sífilis materna do modelo Spectrum e percentuais de mulheres que fizeram testes de detecção e foram tratadas para sífilis, segundo as definições de casos da Organização Mundial da Saúde (OMS) e probabilidades de risco. Resultados O modelo Spectrum estimou, para 2016, uma prevalência de gonorreia de 0,70% (intervalo de confiança de 95% [IC 95%] 0,15%-1,9%) no sexo feminino e 0,60% (0,1%-1,9%) no sexo masculino e uma prevalência de clamídia de 9,2% (4,4%-15,4%) no sexo feminino e 7,4% (3,5%-14.7%) no sexo masculino, sem evidência de tendências no período 1995-2016. A prevalência de sífilis ativa em 2016 foi de 1,25% (1,22-1,29%) no sexo feminino e 1,25% (1,1%-1,4%) no sexo masculino, demonstrando um declínio da prevalência de 2,6% (2,1%-3,2%) observada em 1995 para o sexo feminino. Houve, ao todo, 3.851 casos correspondentes de SC em 2016 (incluindo casos assintomáticos), dos quais 2.245 foram desfechos adversos congênitos. Observou-se uma redução nas estimativas anuais de SC e desfechos adversos congênitos em 2008-2016, refletindo a diminuição da prevalência materna e o número crescente de casos evitados com exames pré-natais de detecção e tratamento. Conclusões Os dados disponíveis de vigilância e monitoramento condensados no modelo Spectrum-STI, e as resultantes estimativas nacionais de infeções sexualmente transmissíveis (IST) obtidas pela primeira vez na Colômbia, evidenciam a alta carga persistente de IST no país. Estima-se que a ocorrência de sífilis do adulto e sífilis congênita esteja diminuindo em decorrência da melhoria nos esforços de detecção precoce. A vigilância reforçada, consistindo também de exames periódicos de detecção precoce nas populações de baixo risco e estimavas futuras aprimoradas do instrumento Spectrum, deve sustentar o planejamento e a implementação de controle e prevenção de IST e a eliminação da SC.

The prevalence and incidence of active syphilis in women in Morocco, 1995-2016: Model-based estimation and implications for STI surveillance.

BACKGROUND: Evolving health priorities and resource constraints mean that countries require data on trends in sexually transmitted infections (STI) burden, to inform program planning and resource allocation. We applied the Spectrum STI estimation tool to estimate the prevalence and incidence of active syphilis in adult women in Morocco over 1995 to 2016. The results from the analysis are being used to inform Morocco's national HIV/STI strategy, target setting and program evaluation. METHODS: Syphilis prevalence levels and trends were fitted through logistic regression to data from surveys in antenatal clinics, women attending family planning clinics and other general adult populations, as available post-1995. Prevalence data were adjusted for diagnostic test performance, and for the contribution of higher-risk populations not sampled in surveys. Incidence was inferred from prevalence by adjusting for the average duration of infection with active syphilis. RESULTS: In 2016, active syphilis prevalence was estimated to be 0.56% in women 15 to 49 years of age (95% confidence interval, CI: 0.3%-1.0%), and around 21,675 (10,612-37,198) new syphilis infections have occurred. The analysis shows a steady decline in prevalence from 1995, when the prevalence was estimated to be 1.8% (1.0-3.5%). The decline was consistent with decreasing prevalences observed in TB patients, fishermen and prisoners followed over 2000-2012 through sentinel surveillance, and with a decline since 2003 in national HIV incidence estimated earlier through independent modelling. CONCLUSIONS: Periodic population-based surveys allowed Morocco to estimate syphilis prevalence and incidence trends. This first-ever undertaking engaged and focused national stakeholders, and confirmed the still considerable syphilis burden. The latest survey was done in 2012 and so the trends are relatively uncertain after 2012. From 2017 Morocco plans to implement a system to record data from routine antenatal programmatic screening, which should help update and re-calibrate next trend estimations.

The case for investing in the male condom.

When used correctly and consistently, the male condom offers triple protection from unintended pregnancy and the transmission of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV). However, with health funding levels stagnant or falling, it is important to understand the cost and health impact associated with prevention technologies. This study is one of the first to attempt to quantify the cost and combined health impact of condom use, as a means to prevent unwanted pregnancy and to prevent transmission of STIs including HIV. This paper describes the analysis to make the case for investment in the male condom, including the cost, impact and cost-effectiveness by three scenarios (low in which 2015 condom use levels are maintained; medium in which condom use trends are used to predict condom use from 2016-2030; and high in which condom use is scaled up, as part of a package of contraceptives, to meet all unmet need for family planning by 2030 and to 90% for HIV and STI prevention by 2016) for 81 countries from 2015-2030. An annual gap between current and desired use of 10.9 billion condoms was identified (4.6 billion for family planning and 6.3 billion for HIV and STIs). Under a high scenario that completely reduces that gap between current and desired use of 10.9 billion condoms, we found that by 2030 countries could avert 240 million DALYs. The additional cost in the 81 countries through 2030 under the medium scenario is $1.9 billion, and $27.5 billion under the high scenario. Through 2030, the cost-effectiveness ratios are $304 per DALY averted for the medium and $115 per DALY averted for the high scenario. Under the three scenarios described above, our analysis demonstrates the cost-effectiveness of the male condom in preventing unintended pregnancy and HIV and STI new infections. Policy makers should increase budgets for condom programming to increase the health return on investment of scarce resources.

Estimating prevalence trends in adult gonorrhoea and syphilis in low- and middle-income countries with the Spectrum-STI model: results for Zimbabwe and Morocco from 1995 to 2016.

OBJECTIVE: To develop a tool for estimating national trends in adult prevalence of sexually transmitted infections by low- and middle-income countries, using standardised, routinely collected programme indicator data. METHODS: The Spectrum-STI model fits time trends in the prevalence of active syphilis through logistic regression on prevalence data from antenatal clinic-based surveys, routine antenatal screening and general population surveys where available, weighting data by their national coverage and representativeness. Gonorrhoea prevalence was fitted as a moving average on population surveys (from the country, neighbouring countries and historic regional estimates), with trends informed additionally by urethral discharge case reports, where these were considered to have reasonably stable completeness. Prevalence data were adjusted for diagnostic test performance, high-risk populations not sampled, urban/rural and male/female prevalence ratios, using WHO's assumptions from latest global and regional-level estimations. Uncertainty intervals were obtained by bootstrap resampling. RESULTS: Estimated syphilis prevalence (in men and women) declined from 1.9% (95% CI 1.1% to 3.4%) in 2000 to 1.5% (1.3% to 1.8%) in 2016 in Zimbabwe, and from 1.5% (0.76% to 1.9%) to 0.55% (0.30% to 0.93%) in Morocco. At these time points, gonorrhoea estimates for women aged 15-49 years were 2.5% (95% CI 1.1% to 4.6%) and 3.8% (1.8% to 6.7%) in Zimbabwe; and 0.6% (0.3% to 1.1%) and 0.36% (0.1% to 1.0%) in Morocco, with male gonorrhoea prevalences 14% lower than female prevalence. CONCLUSIONS: This epidemiological framework facilitates data review, validation and strategic analysis, prioritisation of data collection needs and surveillance strengthening by national experts. We estimated ongoing syphilis declines in both Zimbabwe and Morocco. For gonorrhoea, time trends were less certain, lacking recent population-based surveys.