Global prevalence of hepatitis C virus in women of childbearing age in 2019: a modelling study.

BACKGROUND: Treatment for infection with hepatitis C virus (HCV) during pregnancy has not yet been approved; however, interventions specifically targeting women, especially those of childbearing age (15-49 years), could prevent vertical transmission and community spread. To assess the impact of such interventions, improved prevalence estimates in this group are needed. We aimed to estimate the global prevalence of viraemic HCV in 2019 among women of childbearing age. METHODS: In this modelling study, we used previously developed models for 110 countries inputted with country-specific demographic and HCV epidemiology data. We did a literature review, searching PubMed, Embase, and grey literature for studies published between Jan 1, 2000, and June 30, 2018, reporting HCV antibody or viraemic prevalence in women of childbearing age. Studies from the literature review and studies in models were compared by use of a data quality scoring system and models were updated, as appropriate, when a better study was identified. We used these HCV disease burden models to calculate the 2019 prevalence of viraemic HCV in women of childbearing age. In countries without a model, prevalence was extrapolated by Global Burden of Disease (GBD) region. FINDINGS: An estimated 14 860 000 (95% uncertainty interval [UI] 9 667 000-18 282 000) women aged 15-49 years had HCV infection worldwide in 2019, corresponding to a viraemic prevalence of 0·78% (95% UI 0·62-0·86). Globally, HCV prevalence increased with age, rising from 0·25% (95% UI 0·20-0·27) in women aged 15-19 years to 1·21% (0·97-1·34) in women aged 45-49 years. China (16% of total infections) and Pakistan (15%) had the greatest numbers of viraemic infections, but viraemic prevalence was highest in Mongolia (5·14%, 95% CI 3·46-6·28) and Burundi (4·91%, 3·80-18·75). Of the countries with 500 cases or more, viraemic prevalence was lowest in Chile (0·07%, 95% UI 0·04-0·12). Among the GBD regions, eastern Europe had the highest viraemic prevalence (3·39%, 95% UI 1·88-3·54). By WHO region, the Eastern Mediterranean region had the highest viraemic prevalence (1·75%, 95% UI 1·26- 1·90). INTERPRETATION: Most research on HCV disease burden among women aged 15-49 years focuses on pregnant women. Using modelling, this analysis provides global and national estimates of HCV prevalence in all women of childbearing age. These data can inform preconception test-and-treat strategies to reduce vertical transmission and total disease burden. FUNDING: Gilead Sciences, John C Martin Foundation, private donors.

Impact of COVID-19 on global HCV elimination efforts.

BACKGROUND & AIMS: Coronavirus disease 2019 (COVID-19) has placed a significant strain on national healthcare systems at a critical moment in the context of hepatitis elimination. Mathematical models can be used to evaluate the possible impact of programmatic delays on hepatitis disease burden. The objective of this analysis was to evaluate the incremental change in HCV liver-related deaths and liver cancer, following a 3-month, 6-month, or 1-year hiatus in hepatitis elimination programs. METHODS: Previously developed models were adapted for 110 countries to include a status quo or 'no delay' scenario and a '1-year delay' scenario assuming significant disruption in interventions (screening, diagnosis, and treatment) in the year 2020. Annual country-level model outcomes were extracted, and weighted averages were used to calculate regional (WHO and World Bank Income Group) and global estimates from 2020 to 2030. The incremental annual change in outcomes was calculated by subtracting the 'no-delay' estimates from the '1-year delay' estimates. RESULTS: The '1-year delay' scenario resulted in 44,800 (95% uncertainty interval [UI]: 43,800-49,300) excess hepatocellular carcinoma cases and 72,300 (95% UI: 70,600-79,400) excess liver-related deaths, relative to the 'no-delay' scenario globally, from 2020 to 2030. Most missed treatments would be in lower-middle income countries, whereas most excess hepatocellular carcinoma and liver-related deaths would be among high-income countries. CONCLUSIONS: The impact of COVID-19 extends beyond the direct morbidity and mortality associated with exposure and infection. To mitigate the impact on viral hepatitis programming and reduce excess mortality from delayed treatment, policy makers should prioritize hepatitis programs as soon as it becomes safe to do so. LAY SUMMARY: COVID-19 has resulted in many hepatitis elimination programs slowing or stopping altogether. A 1-year delay in hepatitis diagnosis and treatment could result in an additional 44,800 liver cancers and 72,300 deaths from HCV globally by 2030. Countries have committed to hepatitis elimination by 2030, so attention should shift back to hepatitis programming as soon as it becomes appropriate to do so.

A tool to measure the economic impact of Hepatitis B elimination: A case study in Saudi Arabia.

BACKGROUND: No virologic cure exists for hepatitis B virus (HBV) infection, and existing therapies are designed to control viral replication. We aimed to estimate the national prevalence of HBsAg in 2017 and study the impact of an enhanced diagnosis rate and universal treatment administration on HBV-related outcomes in Saudi Arabia. MATERIALS AND METHODS: A dynamic transmission and disease burden model was developed to estimate the future economic burden of HBV infection. The infected population was tracked by age and gender-defined cohorts; direct costs (healthcare, screening, diagnostics and treatment) and indirect costs (disability-adjusted life years and the value of a statistical life year) were calculated. The impact of two intervention scenarios (Achieve WHO Targets: diagnose 90% of infections and treat 80% of high viral load patients by 2030; and Diagnose and Treat All: diagnose and treat all infected patients by 2022) were compared against the Base Case scenario (no policy action), with near-universal vaccination coverage rates held constant. A sensitivity analysis of future treatment cost was also conducted. RESULTS: In 2017, HBsAg prevalence was estimated at 1.7%, corresponding to 574,000 infections. The same year, there was an estimated incidence of 490 cases of decompensated cirrhosis, 1500 cases of hepatocellular carcinoma (HCC) and 1740 liver-related deaths (LRD). HBsAg prevalence was 0.1% among 5-year-olds and <0.1% among infants. Disease burden outcomes by 2030, as compared with 2015, were as follows - Base Case: LRDs and HCC incidence were projected to increase by 70%. WHO Targets: A 30-35% decline in both HCC incidence and LRDs. Diagnose and Treat All: A 50-55% decline in HCC incidence and LRDs. In all scenarios, HBsAg prevalence among infants and 5-year-olds declined to <0.1% with the Diagnose and Treat all scenario resulting in a prevalence approaching zero in this age group. Annual direct costs are projected to increase and peak by 2022 in both intervention scenarios due to expansion of treatment and diagnostics. However, these are offset by the reduction of indirect economic costs, starting immediately in the WHO Targets scenario and by 2023 in the strategy to diagnose and treat all. Achieving WHO Targets is estimated to achieve a positive return on investment (ROI) by 2021 when examining direct costs and indirect economic losses at a treatment price of $2700 USD per patient yearly. Diagnosing and treating all patients, however, would require at least a 50% reduction in the unit cost of treatment to achieve a positive ROI by 2029. CONCLUSIONS: Increased diagnosis and treatment rates of HBV would lead to substantial declines in HCC and LRD. This effect would be dramatically enhanced by administering treatment to all HBV cases regardless of viral load and estimated to be highly cost-effective if treatment prices can be substantially reduced.

Novel PCR exclusion assay to detect spotted fever group rickettsiae in the lone star tick (Amblyomma americanum).

The lone star tick (Amblyomma americanum) is the most common and abundant human-biting tick in the southeastern United States where spotted fever rickettsioses frequently occur. However, the role of this tick in transmitting and maintaining pathogenic and non-pathogenic spotted fever group rickettsiae (SFGR) remains poorly defined. This is partially due to the high prevalence and abundance of Rickettsia amblyommatis in most populations of A. americanum. Many molecular assays commonly employed to detect rickettsiae use PCR primers that target highly conserved regions in the SFGR so low abundance rickettsia may not be detected when R. amblyommatis is present. It is costly and inefficient to test for low abundance rickettsial agents with multiple individual specific assays even when they are multiplexed, as most samples will be negative. Real time PCR assays may also be hampered by inadequate limits of detection (LODs) for low abundance agents. We exploited the absence of an otherwise relatively SFGR-conserved genome region in R. amblyommatis to design a hemi-nested PCR-assay which has a sensitivity of 10 copies in detecting the presence of most SFGR, but not R. amblyommatis in DNA of infected lone star ticks. This deletion is conserved in 21 isolates of R. amblyommatis obtained from multiple states. We demonstrated the assay's utility by detecting a pathogenic SFGR, Rickettsia parkeri, in 15/50 (30 %) of field collected A. americanum ticks that were previously screened with conventional assays and found to be positive for R. amblyommatis. These co-infected ticks included 1 questing female, 6 questing nymphs, and 8 attached males. The high prevalence of R. parkeri among host-attached ticks may be due to several variables and does not necessarily reflect the risk of disease transmission from attached ticks to vertebrate hosts. This novel assay can provide accurate estimates of the prevalence of less common SFGR in A. americanum and thus improve our understanding of the role of this tick in the maintenance and transmission of the SFGR commonly responsible for human rickettsioses.

A tool to measure the impact of inaction toward elimination of hepatitis C: A case study in Korea.

BACKGROUND AND AIMS: Hepatitis C virus (HCV) and its sequelae present a significant source of economic and societal burden. Introduction of highly effective curative therapies has made HCV elimination attainable. The study used a predictive model to assess the clinical and economic impact of implementing national screening and treatment policies toward HCV elimination in Korea. METHODS: A previously validated Markov disease progression model of HCV infection was employed to analyze the clinical and economic impact of various strategies for HCV diagnosis and treatment in Korea. In this analysis, the model compared the clinical and economic outcomes of current HCV-related interventions in Korea (7,000 patients treated and 4,200 patients newly diagnosed annually, starting in 2017) to four elimination scenarios: 1) initiating sufficient diagnosis and treatment interventions to meet the World Health Organization's GHSS elimination targets by 2030, 2) delaying initiation of interventions by one year, 3) delaying initiation of interventions by two years and 4) accelerating initiation of interventions to meet elimination targets by 2025. Modelled historical incidence of HCV was calibrated to match a viremic HCV prevalence of 0.44% in 2009. Elimination scenarios required 24,000 treatments and 34,000 newly diagnosed patients annually, starting in 2018, to reach the 2030 targets. RESULTS: Compared to current "status quo" interventions, elimination (or accelerated elimination by 2025) would avert 23,700 (27,000) incident cases of HCV, 1,300 (1,400) liver-related deaths (LRDs) and 2,900 (3,100) cases of end-stage liver disease (ESLD) over the 2017-2030 time period. Postponing interventions by one (or two) years would avert 21,100 (18,600) new HCV infections, 920 (660) LRDs and 2,000 (1,400) cases of ESLD by 2030. Following elimination or accelerated elimination strategies would save 860 million USD or 1.1 billion USD by 2030, respectively, compared to the status quo, requiring an up-front investment in prevention that decreases spending on liver-related complications and death. CONCLUSIONS: By projecting the impact of interventions and tracking progress toward GHSS elimination targets using modelling, we demonstrate that Korea can prevent significant morbidity, mortality and spending on HCV. Results should serve as the backbone for policy and decision-making, demonstrating how aggressive prevention measures are designed to reduce future costs and increase the health of the public.

Global prevalence of hepatitis C virus in children in 2018: a modelling study.

BACKGROUND: Hepatitis C virus (HCV) prevalence estimates for adults and high-risk groups have been widely published, but the disease burden in children is poorly understood. Direct-acting antiviral drugs, which are considered to be highly effective curative therapies for HCV, are now approved for paediatric patients as young as 3 years. Reliable prevalence estimates for this population are needed to inform scale-up of treatment and national strategies. This analysis combines past modelling and epidemiological work in 104 countries and territories to estimate global HCV prevalence in children in 2018. METHODS: In this modelling study, a comprehensive literature review for articles published between Jan 1, 2000, and March 31, 2019, was used to determine historical HCV prevalence estimates in children in all 249 countries and territories of the world. We identified published HCV prevalence estimates for children aged 0-18 years who are not at high risk of HCV infection in 39 countries and territories and inputted them into dynamic Markov disease-burden models to estimate viraemic HCV prevalence in 2018. For 25 of them, which had complete data, available information on HCV prevalence in children was used to build regression models to predict paediatric prevalence in an additional 65 countries and territories that had country-specific or territory-specific data about predictors only. Regression models were created for each 5-year paediatric age cohort from 0 to 19 years, considering several predictor variables. The data and forecasts from the 104 countries and territories for which data were available were used to calculate HCV prevalence by Global Burden of Disease region, which was then applied to the remaining 145 countries and territories to generate a global estimate. FINDINGS: The global estimate for viraemic prevalence in the paediatric population aged 0-18 years was 0·13% (95% uncertainty interval 0·08-0·16), corresponding to 3·26 million (2·07-3·90) children with HCV in 2018. HCV prevalence increased with age in all countries and territories. HCV prevalence in women of childbearing age was the strongest predictor of HCV prevalence in children aged 0-4 years (p<0·0001). Prevalence of HCV in adults was significantly associated with HCV prevalence in children aged 5-19 years (p<0·0001), and the proportion of HCV infections in people who inject drugs was significantly associated with HCV prevalence in children aged 15-19 years (p=0·036). INTERPRETATION: Most studies on HCV prevalence in children focus on high-risk groups and highly endemic geographic areas. Our analysis provides global prevalence estimates of HCV in the paediatric population. Treatment in paediatric patients requires different clinical and population health management optimisation than in adults. Because of this heterogeneity, country-specific or territory-specific and age-specific HCV prevalence estimates can help countries and territories to improve national HCV elimination strategies. FUNDING: Gilead Sciences, John C Martin Foundation, and private donors.

Cost analysis of different cervical cancer screening strategies in Mexico / Análisis de costos de distintas estrategias de tamizaje para cáncer cervical en México

Objective. To compare the costs and number of undetected cases of four cervical cancer screening strategies (CCSS) in Mexico. Materials and methods. We estimated the costs and outcomes of the following CCSS: a) conventional Papanicolaou smear (Pap) alone; b) high-risk human papilloma virus testing (HR-HPV) as primary screening with Pap as reflex triage; c) HR-HPV as primary screening with HPV-16/18 typing, liquid-based cytology (LBC) and immunostaining for p16/Ki67 testing as reflex triage, and d) co-testing with HR-HPV and LBC with HPV-16/18 typing and immunostaining for p16/Ki67 as reflex triage. The outcome of interest was high-grade cervical lesions or cervical cancer. Results. HR-HPV testing, HPV typing, LBC testing and immunostaining is the best alternative because it is the least expensive option with an acceptable number of missed cases. Conclusions. The opportunity costs of a poor quality CCSS is many false negatives. Combining multiple tests may be a more cost-effective way to screen for cervical cancer in Mexico.

Objetivo. Comparar los costos y los casos no detectados de cuatro estrategias de tamizaje de cáncer cervical (ETCC) en México. Material y métodos. Se estimaron los costos y resultados en salud de las siguientes ETCC: a) citología convencional como único procedimiento de tamizaje; b) detección de virus del papiloma humano de alto riesgo (VPH-AR) como tamizaje primario y citología convencional como procedimiento de triage; c) detección de VPH-AR como tamizaje primario y tipificación de VPH-16/18, citología en base líquida e inmunotinción para p16/Ki67 como procedimientos de triage, y d) evaluación conjunta con VPH-AR y citología en base líquida como tamizaje primario y tipificación de VPH-16/18 e inmunotinción para p16/Ki67 como procedimientos de triage. El resultado en salud analizado fueron los casos de neoplasia intraepitelial cervical (CIN 2/3) o cáncer cervical detectados. Resultados. La ETCC basada en la detección de VPH-AR como prueba primaria y seguida de la tipificación de VPH-16/18, la citología en base líquida y la inmunotinción para p16/Ki67 como procedimientos de triage es la mejor alternativa, ya que es la menos costosa y la que tuvo un nivel aceptable de casos perdidos. Conclusiones. El costo de oportunidad de una ETCC de mala calidad es un alto número de falsos negativos. La combinación seriada de varias pruebas de tamizaje y triage puede ser una alternativa costo-efectiva para la detección oportuna de cáncer cervical en México.

Cost analysis of different cervical cancer screening strategies in Mexico.

OBJECTIVE: To compare the costs and number of undetected cases of four cervical cancer screening strategies (CCSS) in Mexico. MATERIALS AND METHODS: We estimated the costs and outcomes of the following CCSS: a) conventional Papanicolaou smear (Pap) alone; b) high-risk human papilloma virus testing (HR-HPV) as primary screening with Pap as reflex triage; c) HR-HPV as primary screening with HPV-16/18 typing, liquid-based cytology (LBC) and immunostaining for p16/Ki67 testing as reflex triage, and d) co-testing with HR-HPV and LBC with HPV-16/18 typing and immunostaining for p16/Ki67 as reflex triage. The outcome of interest was high-grade cervical lesions or cervical cancer. RESULTS: HR-HPV testing, HPV typing, LBC testing and immunostaining is the best alternative because it is the least expensive option with an acceptable number of missed cases. CONCLUSIONS: The opportunity costs of a poor quality CCSS is many false negatives. Combining multiple tests may be a more cost-effective way to screen for cervical cancer in Mexico.