Modelling the elimination of hepatitis C as a public health threat in Iceland: A goal attainable by 2020

Epidemiological Modeling of the Impact of Public Health Policies on Hepatitis C: Protocol for a Gamification Tool Targeting Microelimination

BACKGROUND

Hepatitis C is a disease with a strong social component, as its main transmission route is via blood, making it associated with lifestyle. Therefore, it is suitable to be worked on from the perspective of public health policy, which still has a lot of room to explore and improve, contrary to diagnoses and treatments, which are already very refined and effective.

OBJECTIVE

An interactive gamified policy tool, designated as Let's End HepC (LEHC), was created to understand the impact of policies related to hepatitis C on the disease's epidemiology on a yearly basis until 2030.

METHODS

To this end, an innovative epidemiological model was developed, integrating Markov chains to model the natural history of the disease and adaptive conjoint analysis to reflect the degree of application of each of the 24 public health policies included in the model. This double imputation model makes it possible to assess a set of indicators such as liver transplant, incidence, and deaths year by year until 2030 in different risk groups. Populations at a higher risk were integrated into the model to understand the specific epidemiological dynamics within the total population of each country and within segments that comprise people who have received blood products, prisoners, people who inject drugs, people infected through vertical transmission, and the remaining population.

RESULTS

The model has already been applied to a group of countries, and studies in 5 of these countries have already been concluded, showing results very close to those obtained through other forms of evaluation.

CONCLUSIONS

The LEHC model allows the simulation of different degrees of implementation of each policy and thus the verification of its epidemiological impact on each studied population. The gamification feature allows assessing the adequate fulfillment of the World Health Organization goals for the elimination of hepatitis C by 2030. LEHC supports health decision makers and people who practice patient advocacy in making decisions based on science, and because LEHC is democratically shared, it ends up contributing to the increase of citizenship in health.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/38521.

Application of machine learning to predict hospital visits for respiratory diseases using meteorological and air pollution factors in Linyi, China

Urbanization and industrial development have resulted in increased air pollution, which is concerning for public health. This study evaluates the effect of meteorological factors and air pollution on hospital visits for respiratory diseases (pneumonia, acute upper respiratory infections, and chronic lower respiratory diseases). The test dataset comprises meteorological parameters, air pollutant concentrations, and outpatient hospital visits for respiratory diseases in Linyi, China, from January 1, 2016 to August 20, 2022. We use support vector regression (SVR) to build models that enable analysis of the effect of meteorological factors and air pollutants on the number of outpatient visits for respiratory diseases. Spearman correlation analysis and SVR model results indicate that NO2, PM2.5, and PM10 are correlated with the occurrence of respiratory diseases, with the strongest correlation relating to pneumonia. An increase in the daily average temperature and daily relative humidity decreases the number of patients with pneumonia and chronic lower respiratory diseases but increases the number of patients with acute upper respiratory infections. The SVR modeling has the potential to predict the number of respiratory-related hospital visits. This work demonstrates that machine learning can be combined with meteorological and air pollution data for disease prediction, providing a useful tool whereby policymakers can take preventive measures.

Identifying barriers and facilitators of the inclusion of pregnant individuals in hepatitis C treatment programs in the United States

BACKGROUND

The rising prevalence of hepatitis C virus (HCV) infection and the availability of direct acting antivirals for HCV treatment has prompted a public health goal of HCV eradication. Despite the availability of treatment for HCV, treatment programs have generally excluded pregnant individuals. Our objective was to query patients and clinicians to identify barriers to including pregnant individuals in HCV treatment programs.

METHODS AND FINDINGS

This qualitative investigation included obstetricians and previously/currently pregnant individuals with HCV. Participants completed interviews regarding knowledge of and attitudes towards HCV treatment and perceived barriers to treatment during pregnancy. Data were analyzed using the constant comparative method. Obstetricians (N = 18) and patients (N = 21) described concerns about equity, access, and cost. Both expressed uncertainty about safety and confirmed a need for clinician education. Obstetricians emphasized the lack of professional guidelines. Although some clinicians expressed concern about patient adherence and engagement, patients were largely desirous of treatment; both groups identified potential benefits of antenatal treatment.

CONCLUSIONS

Both patients and obstetricians were generally receptive to HCV treatment in pregnancy and recognized pregnancy as an important window of opportunity for treatment. Our findings suggest the need for further research on maternal-fetal safety of HCV treatment as well as on interventions to ensure fair and appropriate access to HCV treatment for pregnant individuals.

HIGH RATE OF HCV REINFECTION AMONG RECENTLY INJECTING DRUG USERS: RESULTS FROM THE TRAP HEP C PROGRAM - A PROSPECTIVE NATIONWIDE, POPULATION-BASED STUDY

BACKGROUND

The Treatment as Prevention for Hepatitis C program started in 2016 in Iceland, offering treatment with direct-acting antivirals to hepatitis C virus (HCV)-infected individuals. Reinfections through injection drug use (IDU) can hamper elimination efforts. We determined reinfection rates (RIR) of HCV among patients in the program.

METHODS

Clinical data were gathered prospectively. The study cohort consisted of HCV-cured patients with an estimated sustained virologic response between February 1st 2016 and November 20th 2018, with follow-up until November 20th 2019. The observation period and time until reinfection was estimated using a single random point imputation method coupled with Monte Carlo simulation. The RIR was expressed as reinfections/100 person-years (PYs).

RESULTS

640 treatments of 614 patients (417 males, mean age 44.3 years) resulted in cure, with 52 reinfections subsequently confirmed in 50 patients (37 males). Follow-up was 672.1 PYs with median time to reinfection of 231.7 days. History of IDU was reported by 523 patients (84.8%) and recent IDU with 220 (34.4%) treatments. Stimulants were the preferred injected drug in 85.5% of patients with history of IDU. The RIR was 7.7/100 PYs. Using multivariate Cox proportional hazards models for interval-censored data, age (HR 0.96, 95% CI 0.94-0.99) and recent IDU (HR 2.91, 95% CI 1.48-5.76) were significantly associated with reinfection risk.

CONCLUSIONS

The RIR is high in a setting of widespread stimulant use, particularly in young people with recent IDU. Regular follow up is important among high-risk populations to diagnose reinfections early and reduce transmission.

A multi-level intervention to eliminate hepatitis C from the Region of Southern Denmark: the C-Free-South project

Denmark has signed the WHO strategy to eliminate hepatitis C virus (HCV). In the absence of a national strategy for elimination, a local action plan was developed in the Region of Southern Denmark (RSD). The aim of the strategy is to diagnose 90% of HCV-infected persons and treat 80% of those diagnosed by 2025. The strategy was developed by reviewing Danish data on HCV epidemiology and drug use to identify key populations for screening, linkage to care, and treatment. Based on available published data from 2016, an estimated 3028 persons in the RSD were HCV-RNA positive (population prevalence 0.21%). Of these, 1002 were attending clinical care, 1299 were diagnosed but not in clinical care, and 727 were undiagnosed. Three different interventions targeting the HCV-infected population and two interventions for HCV surveillance are planned to achieve elimination. The “C-Free-South” strategy aims to eliminate HCV in our region by identifying (90%) and treating (80%) of infected persons by the end of 2025, 5 years earlier than the WHO elimination target date.

Breakthroughs in hepatitis C research: from discovery to cure

In the 1970s, an unknown virus was suspected for documented cases of transfusion-associated hepatitis, a phenomenon called non-A, non-B hepatitis. In 1989, the infectious transmissible agent was identified and named hepatitis C virus (HCV) and, soon enough, the first diagnostic HCV antibody test was developed, which led to a dramatic decrease in new infections. Today, HCV infection remains a global health burden and a major cause of liver cirrhosis, hepatocellular carcinoma and liver transplantation. However, tremendous advances have been made over the decades, and HCV became the first curable, chronic viral infection. The introduction of direct antiviral agents revolutionized antiviral treatment, leading to viral eradication in more than 98% of all patients infected with HCV. This Perspective discusses the history of HCV research, which reads like a role model for successful translational research: starting from a clinical observation, specific therapeutic agents were developed, which finally were implemented in national and global elimination programmes.

Planning the hepatitis C virus elimination in Cyprus: A modeling study

BACKGROUND

Hepatitis C virus (HCV) infection is a major global public health problem. In the Republic of Cyprus, the estimated prevalence of chronic hepatitis C (CHC) among the general population is 0.6%, while the CHC prevalence among people who inject drugs (PWID) is estimated at 46%. Direct-acting antivirals that can eliminate HCV are not yet widely available in the Republic of Cyprus. However, when direct-acting antivirals become available, a long-term strategic plan to guide elimination efforts will be needed to maximize the effect of treatment.

AIM

To determine the programmatic targets to eliminate HCV in the Republic of Cyprus.

METHODS

A dynamic, stochastic, individual-based model of HCV transmission, disease progression, and cascade of care was calibrated to data from Cyprus. The model stratifies the population into the infected general population and the PWID population. A variety of test, prevention, and treatment strategies concerning the general population, PWID, or both were examined. The time horizon of the analysis was until 2034.

RESULTS

Under the status quo scenario, the model predicted that 75 (95% confidence interval (CI): 60, 91) and 575 (95%CI: 535, 615) liver-related deaths and new infections would occur by 2034, respectively. Launching an expanded treatment program, without screening interventions, would cause modest outcomes regarding CHC prevalence (16.6% reduction in 2034 compared to 2020) and liver-related deaths (10 deaths would be prevented compared to the status quo scenario by 2034). Implementing a test and treat strategy among the general population but without any intervention in the PWID population would suffice to meet the mortality target but not the incidence target. To achieve HCV elimination in Cyprus, 3080 (95%CI: 3000, 3200) HCV patients need to be diagnosed and treated by 2034 (2680 from the general population and 400 from PWID), and harm reduction coverage among PWID should be increased by 3% per year (from 25% in 2020 to 67% in 2034).

CONCLUSION

Elimination of HCV is a demanding public health strategy, which requires significant interventions both among the general population and high-risk groups.

Can hepatitis C elimination targets be sustained among people who inject drugs post-2030?

BACKGROUND

In high-income countries, people who inject drugs (PWID) are a priority population for eliminating hepatitis C virus (HCV) by 2030. Despite evidence informing micro-elimination strategies, little is known regarding efforts needed to maintain elimination targets in populations with ongoing acquisition risks. This model-based study investigates post-elimination transmission dynamics of HCV and HIV among PWID under different scenarios where harm reduction interventions and HCV testing and treatment are scaled-down.

METHODS

We calibrated a dynamic compartmental model of concurrent HCV and HIV transmission among PWID in Montréal (Canada) to epidemiological data (2003-2018). We then simulated achieving the World Health Organization elimination targets by 2030. Finally, we assessed the impact of four post-elimination scenarios (2030-2050): 1) scaling-down testing, treatment, opioid agonist therapy (OAT), and needle and syringe programs (NSP) to pre-2020 levels; 2) only scaling-down testing and treatment; 3) suspending testing and treatment, while scaling down OAT and NSP to pre-2020 levels; 4) suspending testing and treatment and maintaining OAT and NSP coverage required for elimination.

RESULTS

Scaling down interventions to pre-2020 levels (scenario 1) leads to a modest rebound in chronic HCV incidence from 2.4 to 3.6 per 100 person-years by 2050 (95% credible interval - CrI: 0.8-7.2). When only scaling down testing and treatment (scenario 2), chronic HCV incidence continues to decrease. In scenario 3 (suspending treatment and scaling down OAT and NSP), HCV incidence and mortality rapidly increase to 11.4 per 100 person-years (95%CrI: 7.4-15.5) and 3.2 per 1000 person-years (95%CrI: 2.4-4.0), respectively. HCV resurgence was mitigated in scenario 4 (maintaining OAT and NSP) as compared to scenario 3. All scenarios lead to decreases in the proportion of reinfections among incident cases and have little impact on HIV incidence and HIV-HCV coinfection prevalence.

CONCLUSION

Despite ongoing transmission risks, HCV incidence rebounds slowly after 2030 under pre-2020 testing and treatment levels. This is heightened by maintaining high-coverage harm reduction interventions. Overall, sustaining elimination would require considerably less effort than achieving it.

Cascade of care during the first 36 months of the treatment as prevention for hepatitis C (TraP HepC) programme in Iceland: a population-based study

BACKGROUND

WHO has set targets to eliminate hepatitis C virus (HCV) infection as a global health threat by 2030 through a 65% reduction in HCV-related deaths and 80% reduction in HCV incidence. To achieve these goals, WHO set service coverage targets of 90% of the infected population being diagnosed and 80% of eligible patients being treated. In February, 2016, Iceland initiated a nationwide HCV elimination programme known as treatment as prevention for hepatitis C (TraP HepC), which aimed to maximise diagnosis and treatment access. This analysis reports on the HCV cascade of care in the first 3 years of the programme.

METHODS

This population-based study was done between Feb 10, 2016, and Feb 10, 2019. Participants aged 18 years or older with permanent residence in Iceland and PCR-confirmed HCV were offered direct-acting antiviral (DAA) therapy. The programme used a multidisciplinary team approach in which people who inject drugs were prioritised. Nationwide awareness campaigns, improved access to testing, and harm reduction services were scaled up simultaneously. The number of infected people in the national HCV registry was used in combination with multiple other data sources, including screening of low-risk groups and high-risk groups, to estimate the total number of HCV infections. The number of people diagnosed, linked to care, initiated on treatment, and cured were recorded during the study. This study is registered with ClinicalTrials.gov, NCT02647879.

FINDINGS

In February, 2016, at the onset of the programme, 760 (95% CI 690-851) individuals were estimated to have HCV infection, with 75 (95% CI 6-166) individuals undiagnosed. 682 individuals were confirmed to be HCV PCR positive. Over the next 3 years, 183 new infections (including 42 reinfections) were diagnosed, for a total of 865 infections in 823 individuals. It was estimated that more than 90% of all domestic HCV infections had been diagnosed as early as January, 2017. During the 3 years, 824 (95·3%) of diagnosed infections were linked to care, and treatment was initiated for 795 (96·5%) of infections linked to care. Cure was achieved for 717 (90·2%) of 795 infections.

INTERPRETATION

By using a multidisciplinary public health approach, involving tight integration with addiction treatment services, the core service coverage targets for 2030 set by WHO have been reached. These achievements position Iceland to be among the first nations to subsequently achieve the WHO goal of eliminating HCV as a public health threat.

FUNDING

The Icelandic Government and Gilead Sciences.

Excitable models: Projections, targets, and the making of futures without disease

In efforts to control disease, mathematical models and numerical targets play a key role. We take the elimination of a viral infection as a case for exploring mathematical models as 'evidence-making interventions'. Using interviews with mathematical modellers and implementation scientists, and focusing on the emergence of models of 'treatment-as-prevention' in hepatitis C control, we trace how projections detach from their calculative origins as social and policy practices. Drawing on the work of Michel Callon and others, we show that modelled projections of viral elimination circulate as 'qualculations', taking flight via their affects, including as anticipation. Modelled numerical targets do not need 'actual numbers' or precise measurements to perform their authority as evidence of viral elimination or as situated matters-of-concern. Modellers grapple with the ways that their models transform in policy and social practices, apparently beyond reasonable calculus. We highlight how practices of 'holding-on' to projections in relation to imaginaries of 'evidence-based' science entangle with the 'letting-go' of models beyond calculus. We conclude that the 'virtual precision' of models affords them fluid evidence-making potential. We imagine a different mode of modelling science in health, one more attuned to treating projections as qualculative, affective and relational, as excitable matter.

We Must Do Better: Addressing HCV Treatment Barriers in Persons Who Inject Drugs in the United States

The opioid epidemic in the United States, along with a lack of adequate harm reduction services, has contributed to a sharp rise in hepatitis C virus (HCV) infections. Despite considerable evidence of the effectiveness of HCV treatment in people who inject drugs (PWID), and recommendations from clinical guidelines to prioritize treatment in PWID, there are multiple barriers to broad uptake of HCV treatment. These barriers exist at the systems level, as well as at the level of medical providers and patients. Interventions to remove treatment barriers in the United States include harm reduction services, simplifying HCV testing algorithms, improved linkage to HCV care services, and application of new treatment models including colocating services at substance use disorder treatment programs. By following the lead of other countries who have addressed the barriers to HCV treatment, the United States has opportunities to do better in addressing the consequences of the opioid epidemic, including chronic HCV infection.

Current and future strategies for the treatment of chronic hepatitis C

Chronic hepatitis C infection is a major cause of liver disease and hepatocellular carcinoma worldwide. While hepatitis C has been treated for decades with some success, the introduction of direct acting antiviral agents has revolutionized the treatment of hepatitis C with finite, highly effective, well-tolerated therapy and there are few populations that cannot be successfully treated now or are complicated to manage. The World Health Organization has released elimination targets in an effort to eliminate viral hepatitis and reduce dramatically the morbidity and mortality caused by both viral hepatitis. While hepatitis C is straightforward to treat, it remains problematic to eliminate on a global scale. Diagnosis of hepatitis C remains the major gap in the cascade of care and numerous screening strategies will be required to reduce this gap. While historically, treatment of hepatitis C has been centralized, decentralized approaches will be required to diagnose, evaluate, and link to care the large population of individuals worldwide with hepatitis C across low-, middle-, and high-income countries. With the introduction of multiple pangenotypic treatment options and reduced cost for these therapies, assessment and treatment for those with hepatitis C has been simplified and made more accessible worldwide. There are multiple populations for whom care models are being developed and refined, including those when inject drugs, those who are incarcerated, those who present with sexually transmitted disease including the men who have sex with men population, amongst many others. While a vaccine for hepatitis C remains elusive these efforts continue. Multiple successful elimination efforts have been reported.

The transmissibility of hepatitis C virus: a modelling study in Xiamen City, China

This study aimed at estimating the transmissibility of hepatitis C. The data for hepatitis C cases were collected in six districts in Xiamen City, China from 2004 to 2018. A population-mixed susceptible-infectious-chronic-recovered (SICR) model was used to fit the data and the parameters of the model were calculated. The basic reproduction number (R₀) and the number of newly transmitted cases by a primary case per month (MNI) were adopted to quantitatively assess the transmissibility of hepatitis C virus (HCV). Eleven curve estimation models were employed to predict the trends of R₀ and MNI in the city. The SICR model fits the reported HCV data well (P < 0.01). The median R₀ of each district in Xiamen is 0.4059. R₀ follows the cubic model curve, the compound curve and the power function curve. The median MNI of each district in Xiamen is 0.0020. MNI follows the cubic model curve, the compound curve and the power function curve. The transmissibility of HCV follows a decreasing trend, which reveals that under the current policy for prevention and control, there would be a high feasibility to eliminate the transmission of HCV in the city.

Hepatitis C virus infection in EU/EEA and United Kingdom prisons: opportunities and challenges for action

BACKGROUND

Hepatitis C virus (HCV) transmission in the European Union, European Economic Area and United Kingdom is driven by injecting drug use (IDU), which contributes to the high burden of chronic infection among people in prisons. This study aimed to describe the context, epidemiology and response targeting HCV in prisons across the region.

METHODS

We retrieved and collated HCV-related data from the World Health Organization's Health in Prisons European Database and the European Centre for Disease Prevention and Control's hepatitis C prevalence database. Prisons population data were obtained from the Council of Europe Annual Penal Statistics on prison populations (SPACE I).

RESULTS

There were 12 to 93,266 people in prisons, with rates of 31·5 to 234·9 per 100,000 population. Median age was between 31 and 40 years, with up to 72% foreign nationals. Average detention time ranged from one to 31 months. Ministries of Health had sole authority over prisons health, budget administration and funding in 27, 31 and 8% of 26 reporting countries, respectively. Seroprevalence of HCV antibodies ranged from 2·3% to 82·6% while viraemic infections ranged from 5·7% to 8·2%, where reported. Up to 25·8 and 44% reported current and ever IDU, respectively. Eight countries routinely offered HCV screening on an opt-out basis. Needle and syringe programmes were available in three countries. Among the nine countries with data, the annual number of those who had completed HCV treatment ranged between one and 1215 people in prisons.

CONCLUSIONS

HCV burden in prisons remains high, amidst suboptimal levels of interventions. Systematic monitoring at both local and regional levels is warranted, to advance progress towards the elimination of HCV in the region.

Contemporary Epidemiology of Chronic Liver Disease and Cirrhosis

BACKGROUND & AIMS

Accurate estimates for the contemporary burden of chronic liver disease (CLD) are vital for setting clinical, research, and policy priorities. We aimed to review the incidence, prevalence, and mortality of CLD and its resulting complications, including cirrhosis and hepatocellular carcinoma (HCC).

METHODS

We reviewed the published literature on the incidence, prevalence, trends of various etiologies of CLD and its resulting complications. In addition, we provided updated data from the Centers for Disease Control and Global Burden of Disease Study on the morbidity and mortality of CLD, cirrhosis, and hepatocellular carcinoma (HCC). Lastly, we assessed the strengths and weaknesses of available sources of data in hopes of providing important context to these national estimates of cirrhosis burden.

RESULTS

An estimated 1.5 billion persons have CLD worldwide and the age-standardized incidence of CLD and cirrhosis is 20.7/100,000, a 13% increase since 2000. Similarly, cirrhosis prevalence and mortality has increased in recent years in the United States. The epidemiology of CLD is shifting, reflecting implementation of large-scale hepatitis B vaccination and hepatitis C treatment programs, the increasing prevalence of the metabolic syndrome, and increasing alcohol misuse.

CONCLUSIONS

The global burden of CLD and cirrhosis is substantial. Although vaccination, screening, and antiviral treatment campaigns for hepatitis B and C have reduced the CLD burden in some parts of the world, concomitant increases in injection drug use, alcohol misuse, and metabolic syndrome threaten these trends. Ongoing efforts to address CLD-related morbidity and mortality require accurate contemporary estimates of epidemiology and outcomes.

Accelerating the elimination of hepatitis C in Kuwait: An expert opinion

The hepatitis C virus (HCV) is estimated to affect 71 million people worldwide. In 2016, the World Health Organization adopted the first global health sector strategy to eliminate viral hepatitis as a public health threat by 2030. In December 2018, the European Association for the Study of the Liver, International Liver Foundation convened an expert panel to address the elimination of HCV in Kuwait. Several steps have already been taken to eliminate HCV in Kuwait, including free HCV treatment for Kuwait’s citizens, high blood safety standards, and the implementation of screening and awareness programs. The expert panel made several recommendations aimed at accelerating the elimination of HCV in Kuwait: The development of a national strategy and action plan to guide all HCV elimination activities; the formation of a coordination mechanism to support collaboration between hepatitis working committees; the prioritization of micro-elimination at primary, secondary or tertiary facilities, in prisons and rehabilitation centers; and ensuring the involvement of multiple stakeholders – including relevant civil society groups – in all activities. Enhanced screening and linkage to care should be prioritized in Kuwait, with the expansion of the prescriber base to primary healthcare providers and nurse practitioners to be considered. Raising awareness and educating people about HCV infection also remain essential to achieve the goal of HCV elimination. Lastly, a national HCV registry should be developed to help monitor the implementation of viral hepatitis plans and progress towards achieving national and international targets.

A model of the economic benefits of global hepatitis C elimination: an investment case

Major gains in reducing the burden of hepatitis C are now possible because of the discovery of a cure. The prevention of premature deaths and increased workforce participation among people who are cured are likely to provide substantial indirect economic benefits. We developed an investment case for hepatitis C for the six WHO world regions, which, to our knowledge, is the first to consider both indirect and direct economic benefits in this context. Scaling up of testing and treatment to reach the 2030 WHO hepatitis C elimination targets was estimated to prevent 2·1 million (95% credible interval 1·3-3·2 million) hepatitis C-related deaths and 10 million (4-14 million) new hepatitis C virus infections globally between 2018 and 2030. This elimination strategy was estimated to cost US$41·5 billion (33·1-48·7 billion) in testing, treatment, and health care between 2018 and 2030 ($23·4 billion more than the status quo scenario of no testing or treatment scale up), with a global average of $885 (654-1189) per disability-adjusted life-year averted at 2030. Compared with the status quo scenario, the elimination scenario generated $46·1 billion (35·9-53·8 billion) in cumulative productivity gains by 2030. These indirect costs made elimination cost-saving by 2027, with a net economic benefit of $22·7 billion (17·1-27·9 billion) by 2030. This model shows that countries might be underestimating the true burden of hepatitis C and will benefit from investing in elimination.

Progress Toward Hepatitis C Virus Elimination: Therapy and Implementation

The World Health Organization has called for the elimination of hepatitis C virus (HCV) as a public health threat by 2030. Highly effective direct-acting antiviral agents provide the therapeutic tools required for elimination. In the absence of a vaccine, HCV elimination will require enhanced primary prevention and an increase in the proportions of people diagnosed and treated. Given that globally only 20% of people with chronic HCV are diagnosed, and around 5% have initiated HCV treatment, the task ahead is enormous. But, global public health needs optimism, and countries currently on track for HCV elimination provide a pathway forward.

Assessment of Treatment Strategies to Achieve Hepatitis C Elimination in Canada Using a Validated Model

Importance

Achievement of the World Health Organization (WHO) target of eliminating hepatitis C virus (HCV) by 2030 will require an increase in key services, including harm reduction, HCV screening, and HCV treatment initiatives in member countries. These data are not available for Canada but are important for informing a national HCV elimination strategy.

Objective

To use a decision analytical model to explore the association of different treatment strategies with HCV epidemiology and HCV-associated mortality in Canada and to assess the levels of service increase needed to meet the WHO elimination targets by 2030.

Design, Setting, and Participants

Study participants in this decision analytical model included individuals with hepatitis C virus infection in Canada. Five HCV treatment scenarios (optimistic, very aggressive, aggressive, gradual decrease, and rapid decrease) were applied using a previously validated Markov-type mathematical model. The optimistic and very aggressive treatment scenarios modeled a sustained annual treatment of 10 200 persons and 14 000 persons, respectively, from 2018 to 2030. The aggressive, gradual decrease, and rapid decrease scenarios assessed decreases in treatment uptake from 14 000 persons to 10 000 persons per year, 12 000 persons to 8500 persons per year, and 12 000 persons to 4500 persons per year, respectively, between 2018 and 2030.

Main Outcomes and Measures

Hepatitis C virus prevalence and HCV-associated health outcomes were assessed for each of the 5 treatment scenarios with the goal of identifying strategies to achieve HCV elimination by 2030.

Results

An estimated mean 180 142 persons (95% CI, 122 786-196 862 persons) in Canada had chronic HCV infection at the end of 2017. The optimistic and gradual decrease scenarios estimated a decrease in HCV prevalence from 180 142 persons to 37 246 persons and 37 721 persons, respectively, by 2030. Relative to 2015, this decrease in HCV prevalence was associated with 74%, 69%, and 69% reductions in the prevalence of decompensated cirrhosis, hepatocellular carcinoma, and liver-associated mortality, respectively, leading to HCV elimination by 2030. More aggressive treatment uptake (very aggressive scenario) could result in goal achievement up to 3 years earlier than 2030, although a rapid decrease in the initiation of treatment (rapid decrease scenario) would preclude Canada from reaching the HCV elimination goal by 2030.

Conclusions and Relevance

The study findings suggest that Canada could meet the WHO goals for HCV elimination by 2030 by sustaining the current national HCV treatment rate during the next decade. This target will not be achieved if treatment uptake is allowed to decrease rapidly.

The Elimination of Hepatitis C as a Public Health Threat

Hepatitis C virus is a global public health threat, affecting 71 million people worldwide. Increasing recognition of the impact of this epidemic and recent advances in biomedical and technical approaches to hepatitis C prevention and cure have provided impetus for the World Health Organization (WHO) to call for global elimination of hepatitis C as a public health threat by 2030. This work reviews the feasibility of hepatitis C elimination and pathways to overcome existing and potential future barriers to elimination. Drawing on cost-effectiveness modeling and providing examples of successful implementation efforts across the globe, we highlight the resources and strategies needed to achieve hepatitis C elimination. A timely, multipronged response is required if the 2030 WHO elimination targets are to be achieved. Importantly, achieving hepatitis C elimination will also benefit the community well beyond 2030.

How to think with models and targets: Hepatitis C elimination as a numbering performance

The field of public health is replete with mathematical models and numerical targets. In the case of disease eliminations, modelled projections and targets play a key role in evidencing elimination futures and in shaping actions in relation to these. Drawing on ideas within science and technology studies, we take hepatitis C elimination as a case for reflecting on how to think with mathematical models and numerical targets as 'performative actors' in evidence-making. We focus specifically on the emergence of 'treatment-as-prevention' as a means to trace the social and material effects that models and targets make, including beyond science. We also focus on how enumerations are made locally in their methods and events of production. We trace the work that models and targets do in relation to three analytical themes: governing; affecting; and enacting. This allows us to situate models and targets as technologies of governance in the constitution of health, which affect and are affected by their material relations, including in relation to matters-of-concern which extend beyond calculus. By emphasising models and targets as enactments, we draw attention to how these devices give life to new enumerated entities, which detach from their calculative origins and take flight in new ways. We make this analysis for two reasons: first, as a call to bring the social and enumeration sciences closer together to speculate on how we might think with models and targets differently and more carefully; and second, to encourage an approach to science which treats evidencing-making interventions, such as models and targets, as performative and political.

Interim effect evaluation of the hepatitis C elimination programme in Georgia: a modelling study

BACKGROUND

Georgia has a high prevalence of hepatitis C, with 5·4% of adults chronically infected. On April 28, 2015, Georgia launched a national programme to eliminate hepatitis C by 2020 (90% reduction in prevalence) through scaled-up treatment and prevention interventions. We evaluated the interim effect of the programme and feasibility of achieving the elimination goal.

METHODS

We developed a transmission model to capture the hepatitis C epidemic in Georgia, calibrated to data from biobehavioural surveys of people who inject drugs (PWID; 1998-2015) and a national survey (2015). We projected the effect of the administration of direct-acting antiviral treatments until Feb 28, 2019, and the effect of continuing current treatment rates until the end of 2020. Effect was estimated in terms of the relative decrease in hepatitis C incidence, prevalence, and mortality relative to 2015 and of the deaths and infections averted compared with a counterfactual of no treatment over the study period. We also estimated treatment rates needed to reach Georgia's elimination target.

FINDINGS

From May 1, 2015, to Feb 28, 2019, 54 313 patients were treated, with approximately 1000 patients treated per month since mid 2017. Compared with 2015, our model projects that these treatments have reduced the prevalence of adult chronic hepatitis C by a median 37% (95% credible interval 30-44), the incidence of chronic hepatitis C by 37% (29-44), and chronic hepatitis C mortality by 14% (3-30) and have prevented 3516 (1842-6250) new infections and averted 252 (134-389) deaths related to chronic hepatitis C. Continuing treatment of 1000 patients per month is predicted to reduce prevalence by 51% (42-61) and incidence by 51% (40-62), by the end of 2020. To reach a 90% reduction by 2020, treatment rates must increase to 4144 (2963-5322) patients initiating treatment per month.

INTERPRETATION

Georgia's hepatitis C elimination programme has achieved substantial treatment scale-up, which has reduced the burden of chronic hepatitis C. However, the country is unlikely to meet its 2020 elimination target unless treatment scales up considerably.

FUNDING

CDC Foundation, National Institute for Health Research, National Institutes of Health.

Elimination of hepatitis C in Europe: can WHO targets be achieved?

BACKGROUND

Chronic hepatitis C virus (HCV) infection affects 71 million people worldwide. The availability of highly efficient direct-acting antivirals has revolutionized the treatment landscape with over 95% cure rates. The WHO has launched a global programme to achieve rather ambitious HCV elimination targets for 2030.

OBJECTIVES

This article aims to provide a critical overview of the current HCV elimination programmes in Europe highlighting the elements that should be implemented to achieve elimination and those that are already in place to promote this process.

SOURCES

Review of the recently published literature and opinion of experts in the field.

CONTENT

Elimination of hepatitis C as a public health threat appears to be a difficult task, which should be subdivided into smaller targets, the so-called micro-elimination goals, to increase chances of success. Macro-elimination strategies based on mass-screening are difficult to implement. Evidence supporting the efficacy of micro-elimination comes from key populations, such as people who inject drugs. HCV elimination is proceeding at different speeds in Europe. Some countries are on target with the WHO's objectives whereas others lack economic support and political advocacy, and have insufficient infrastructures to achieve this. The absence of an effective prophylactic vaccine is hampering the process and should be overcome.

IMPLICATIONS

Elimination of hepatitis C worldwide appears plausible, but in several countries probably not within the time frame suggested by the WHO. In the absence of vaccination, universal access to HCV treatment would act as a 'therapeutic' option to reduce transmission, especially in high-risk populations.

Upscaling prevention, testing and treatment to control hepatitis C as a public health threat in Dar es Salaam, Tanzania: A cost-effectiveness model

BACKGROUND

Hepatitis C (HCV) elimination strategies are required for low and middle-income countries (LMICs), because although treatment access is currently limited, this is unlikely to remain the case forever. We estimate and compare the impact, cost and cost-effectiveness of a variety of prevent, test and treat strategies for HCV in Dar es Salaam, Tanzania.

METHODS

A mathematical model.

RESULTS

Without intervention, the HCV epidemic in Dar es Salaam was estimated to result in US$29.1 million in disease costs between 2018 and 2030. Maintaining existing harm reduction coverage (4% needle and syringe program, 42% opioid substitution therapy) over this period was estimated to prevent 22% of injecting drug use-acquired HCV infections compared to a zero coverage scenario. Implementing antibody/RNA, serum-based HCV core antigen (HCVcAg) and dry blood spot (DBS) HCVcAg test/treat programs among PWID increased the total cost by US$0.7 million, US$3.1 million and US$6.5 million respectively by 2030; however this expenditure led to 57%, 61% and 73% reductions in annual incidence among PWID, 25%, 27% and 33% reductions overall annual incidence (PWID+non-PWID), and reduced HCV prevalence among PWID from 27% to 9%, 8% and 5%, respectively. The Ab/RNA, serum-based and DBS HCVcAg test/treat programs cost US$689, US$2857 and US$5400 per disability-adjusted life year averted, respectively, compared to no test/treat program.

CONCLUSION

Primary prevention among PWID can provide important reductions in HCV transmission in the absence of treatment availability. HCV Ab/RNA or serum-based HCVcAg test/treat programs among PWID are likely to be cost-effective in Dar es Salaam, with serum-based HCVcAg test/treat achieving greater impact due to a simpler diagnostic process and better retention in care. If used for regular testing of PWID, the additional coverage benefits of non-laboratory-based DBS HCVcAg tests in LMICs would outweigh their reduced sensitivity.

Dynamic modeling of hepatitis C transmission among people who inject drugs

To reach the WHO goal of hepatitis C elimination, it is essential to identify the number of people unaware of their hepatitis C virus (HCV) infection and to investigate the effect of interventions on the disease transmission dynamics. In many high-income countries, one of the primary routes of HCV transmission is via contaminated needles shared by people who inject drugs (PWIDs). However, substantial underreporting combined with high uncertainty regarding the size of this difficult to reach population, makes it challenging to estimate the core indicators recommended by the WHO. To support progress toward the elimination goal, we present a novel multi-layered dynamic transmission model for HCV transmission within a PWID population. The model explicitly accounts for disease stage (acute and chronic), injection drug use status (active and former PWIDs), status of diagnosis (diagnosed and undiagnosed) and country of disease acquisition (domestic or abroad). First, based on this model, and using routine surveillance data, we estimate the number of undiagnosed PWIDs, the true incidence, the average time until diagnosis, the reproduction numbers and associated uncertainties. Second, we examine the impact of two interventions on disease dynamics: (1) direct-acting antiviral drug treatment, and (2) needle exchange programs. As a proof of concept, we illustrate our results for a specific data set. In addition, we develop a web application to allow our model to be explored interactively and with different parameter values.

Mathematical modeling of hepatitis c virus (HCV) prevention among people who inject drugs: A review of the literature and insights for elimination strategies

In 2016, the World Health Organization issued global elimination targets for hepatitis C virus (HCV), including an 80% reduction in HCV incidence by 2030. The vast majority of new HCV infections occur among people who inject drugs (PWID), and as such elimination strategies require particular focus on this population. As governments urgently require guidance on how to achieve elimination among PWID, mathematical modeling can provide critical information on the level and targeting of intervention are required. In this paper we review the epidemic modeling literature on HCV transmission and prevention among PWID, highlight main differences in mathematical formulation, and discuss key insights provided by these models in terms of achieving WHO elimination targets among PWID. Overall, the vast majority of modeling studies utilized a deterministic compartmental susceptible-infected-susceptible structure, with select studies utilizing individual-based network transmission models. In general, these studies found that harm reduction alone is unlikely to achieve elimination targets among PWID. However, modeling indicates elimination is achievable in a wide variety of epidemic settings with harm reduction scale-up combined with modest levels of HCV treatment for PWID. Unfortunately, current levels of testing and treatment are generally insufficient to achieve elimination in most settings, and require further scale-up. Additionally, network-based treatment strategies as well as prison-based treatment and harm reduction provision could provide important additional population benefits. Overall, epidemic modeling has and continues to play a critical role in informing HCV elimination strategies worldwide.

Elimination of hepatitis C. Positioning document of the Spanish Association for the Study of the Liver (AEEH)

The Spanish Association for the Study of the Liver (AEEH) is convinced that the elimination of hepatitisC virus (HCV) in Spain is possible as long as we are able to use the resources and tools necessary for it. This document reflects the position of the AEEH regarding the elimination of HCV, establishing a wide range of recommendations that can be grouped into five categories: 1)Screening of HCV according to age, of the existence of classic acquisition risk factors of infection, active search of previously diagnosed patients and development of micro-elimination strategies in vulnerable populations; 2)Simplification of HCV diagnosis (one-step diagnosis and diagnosis at the point of patient care); 3)Simplification of patient treatment and improvement of care circuits; 4)Health policy measures, and, finally, 5)Establishment of HCV elimination indicators.

The case for a universal hepatitis C vaccine to achieve hepatitis C elimination

BACKGROUND

The introduction of highly effective direct-acting antiviral (DAA) therapy for hepatitis C has led to calls to eliminate it as a public health threat through treatment-as-prevention. Recent studies suggest it is possible to develop a vaccine to prevent hepatitis C. Using a mathematical model, we examined the potential impact of a hepatitis C vaccine on the feasibility and cost of achieving the global WHO elimination target of an 80% reduction in incidence by 2030 in the era of DAA treatment.

METHODS

The model was calibrated to 167 countries and included two population groups (people who inject drugs (PWID) and the general community), features of the care cascade, and the coverage of health systems to deliver services. Projections were made for 2018-2030.

RESULTS

The optimal incidence reduction strategy was to implement test and treat programmes among PWID, and in settings with high levels of community transmission undertake screening and treatment of the general population. With a vaccine available, the optimal strategy was to include vaccination within test and treat programmes, in addition to vaccinating adolescents in settings with high levels of community transmission. Of the 167 countries modelled, between 0 and 48 could achieve an 80% reduction in incidence without a vaccine. This increased to 15-113 countries if a 75% efficacious vaccine with a 10-year duration of protection were available. If a vaccination course cost US$200, vaccine use reduced the cost of elimination for 66 countries (40%) by an aggregate of US$7.4 (US$6.6-8.2) billion. For a US$50 per course vaccine, this increased to a US$9.8 (US$8.7-10.8) billion cost reduction across 78 countries (47%).

CONCLUSIONS

These findings strongly support the case for hepatitis C vaccine development as an urgent public health need, to ensure hepatitis C elimination is achievable and at substantially reduced costs for a majority of countries.

Scaling Up Hepatitis C Prevention and Treatment Interventions for Achieving Elimination in the United States: A Rural and Urban Comparison

In the United States, hepatitis C virus (HCV) transmission is rising among people who inject drugs (PWID). Many regions have insufficient prevention intervention coverage. Using modeling, we investigated the impact of scaling up prevention and treatment interventions on HCV transmission among PWID in Perry County, Kentucky, and San Francisco, California, where HCV seroprevalence among PWID is >50%. A greater proportion of PWID access medication-assisted treatment (MAT) or syringe service programs (SSP) in urban San Francisco (established community) than in rural Perry County (young, expanding community). We modeled the proportion of HCV-infected PWID needing HCV treatment annually to reduce HCV incidence by 90% by 2030, with and without MAT scale-up (50% coverage, both settings) and SSP scale-up (Perry County only) from 2017. With current MAT and SSP coverage during 2017-2030, HCV incidence would increase in Perry County (from 21.3 to 22.6 per 100 person-years) and decrease in San Francisco (from 12.9 to 11.9 per 100 person-years). With concurrent MAT and SSP scale-up, 5% per year of HCV-infected PWID would need HCV treatment in Perry County to achieve incidence targets-13% per year without MAT and SSP scale-up. In San Francisco, a similar proportion would need HCV treatment (10% per year) irrespective of MAT scale-up. Reaching the same impact by 2025 would require increases in treatment rates of 45%-82%. Achievable provision of HCV treatment, alongside MAT and SSP scale-up (Perry County) and MAT scale-up (San Francisco), could reduce HCV incidence.

Lower HCV treatment uptake in women who have received opioid agonist therapy before and during the DAA era: The ANRS FANTASIO project

BACKGROUND

In the era of direct-acting antivirals (DAA) for the treatment of hepatitis C virus (HCV) infection, HCV treatment uptake remains insufficiently documented in key populations such as people with opioid dependence. Access to opioid agonist therapy (OAT) is facilitated in France through delivery in primary care, and individuals with opioid dependence can be identified as those receiving OAT. Women with opioid dependence are especially vulnerable because of associated sex-related stigma, discrimination, and marginalization, all of which negatively interfere with access to HCV prevention and care. This study, based on data collected between 2012 and 2016 in France, aimed to assess whether (i) chronically HCV-infected women with opioid dependence had lower rates of HCV treatment uptake than their male counterparts during the same period (i.e., study period), and (ii) the advent of DAA resulted in increased treatment uptake rates in these women.

METHODS

Individuals with opioid dependence were identified as those receiving OAT at least once during the study period. Analyses were based on exhaustive anonymous care delivery data from the French national healthcare reimbursement database. We used multinomial logistic regression to estimate sex-based disparities in HCV treatment uptake (DAA or pegylated-interferon (Peg-IFN)-based treatment versus no treatment) while accounting for potential confounders.

RESULTS

The study sample comprised 27,127 individuals, including 5640 (20.8%) women. Median [interquartile range] age was 45 [40-49] years. Between 2012 and 2016, 70.9 (women: 77.2; men: 69.3), 17.3 (14.2; 18.2) and 11.7% (8.6%; 12.5%) of the study sample received, respectively, no HCV treatment, DAA and Peg-IFN-based treatment only. After multiple adjustment for potential confounders, women were 41% (adjusted odds-ratio (AOR) [95% confidence interval (CI]): 0.59[0.53-0.65]) and 28% (0.72[0.66-0.78]) less likely than men to have had Peg-IFN-based and DAA treatment, respectively.

CONCLUSION

Despite increased HCV treatment uptake in women with opioid dependence in the DAA era, rates remain lower than for men. In the coming years, access to DAA treatment will continue to increase in France thanks to a forthcoming simplified model of HCV care which includes primary care as an entry point. Nevertheless, a greater understanding of sex-specific barriers to HCV care and the implementation of appropriate sex-specific measures remain a priority.

Hepatitis C: Is eradication possible?

Hepatitis C has a relevant global impact in terms of morbidity, mortality and economic costs, with more than 70 million people infected worldwide. In the resolution, "Transforming our world: the 2030 Agenda for Sustainable Development" was included as a focus area in the health-related goal with world leaders pledging to "combat" it by 2030. In response, WHO drafted the Global Viral Hepatitis Strategy carrying the ambitious targets to reduce the number of deaths by two-thirds and to increase treatment rates up to 80%. Despite the availability of highly effective therapeutic regimens based on direct-acting antivirals many barriers to HCV eradication still remain. They are related to awareness of the infection, linkage to care, availability of the therapeutic drug regimens and reinfection. Overall, if an effective prophylactic vaccine will not be available, HCV eradication appears difficult to achieve in the future.

Australia on track to achieve WHO HCV elimination targets following rapid initial DAA treatment uptake: A modelling study

Subsidized direct-acting antiviral (DAA) treatment recently became available to all adults living with chronic hepatitis C virus (HCV) in Australia. Based on rapid uptake (32 600 people initiated DAA in 2016), we estimated the impact on HCV epidemiology and mortality in Australia and determined if Australia can meet the WHO HCV elimination targets by 2030. Using a mathematical model, we simulated pessimistic, intermediate and optimistic DAA treatment scenarios in Australia over 2016-2030. We assumed treatment and testing rates were initially higher for advanced fibrosis and the same across HCV transmission risk level sub-populations. We also assumed constant testing rates after 2016. We compared the results to the 2015 level and a counterfactual (IFN-based) scenario. During 2016-2030, we estimated an intermediate DAA treatment scenario (2016, 32 600 treated; 2017, 21 370 treated; 2018 17 100 treated; 2019 and beyond, 13 680 treated each year) would avert 40 420 new HCV infections, 13 260 liver-related deaths (15 320 in viraemic; -2060 in cured) and 10 730 HCC cases, equating to a 53%, 63% and 75% reduction, respectively, compared to the IFN-based scenario. The model also estimated that Australia will meet the WHO targets of incidence and treatment by 2028. Time to a 65% reduction in liver-related mortality varied considerably between HCV viraemic only cases (2026) and all cases (2047). Based on a feasible DAA treatment scenario incorporating declining uptake, Australia should meet key WHO HCV elimination targets in 10 to15 years. The pre-DAA escalation in those with advanced liver disease makes the achievement of the liver-related mortality target difficult.

Epidemiology and Elimination of HCV-Related Liver Disease

Hepatitis C virus (HCV) infection, defined by active carriage of HCV RNA, affects nearly 1.0% of the worldwide population. The main risk factors include unsafe injection drug use and iatrogenic infections. Chronic HCV infection can promote liver damage, cirrhosis and hepatocellular carcinoma (HCC) in affected individuals. The advent of new second-generation, direct-acting antiviral (DAA) agents allow a virological cure in more than 90% of treated patients, and therefore prevent HCV-related complications. Recently, concerns have been raised regarding the safety of DAA-regimens in cirrhotic patients with respect to the occurrence and the recurrence of HCC. Here, we review the current available data on HCV epidemiology, the beneficial effects of therapy, and discuss the recent controversy with respect to the potential link with liver cancer. We also highlight the challenges that have to be overcome to achieve the ambitious World Health Organization objective of HCV eradication by 2030.