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

The 'missing' in the 'endgame' of hepatitis C elimination: A qualitative study in New South Wales, Australia

INTRODUCTION

After a promising start in Australia, elimination efforts for hepatitis C are not on track. Following the global campaign to 'find the missing' in hepatitis C response, this qualitative study explores stakeholder perspectives on the 'missing' in the 'endgame' of hepatitis elimination in the state of New South Wales, Australia.

METHOD

Twenty-eight key informants working in New South Wales, elsewhere in Australia and internationally in high income countries participated in a semi-structured qualitative interview. Analysis examined key informant accounts of the 'missing' in efforts to eliminate hepatitis C.

RESULTS

Participants' accounts framed the missing in relation to epidemiological knowledge, making-up four population categories 'missing' or 'missed' in hepatitis C response. In turn, accounts situated the missing in relation to where and how individuals were presumed to connect, or not, with existing health-care infrastructures. This gave rise to concerns about the capacity of health services to be made available for those at risk or in need, with systems said to create opportunities for people to 'miss out' on hepatitis C services.

DISCUSSION AND CONCLUSIONS

The 'missing' in the 'endgame' of hepatitis C elimination effort is not simply a function of who-populations missed-but of where and how, that is, situation and context. Our findings encourage a focus on how services, systems and contexts may create situations in which people become missed or are 'made missing' from care. We therefore advocate for a systemic, and not only population-based, approach in the final push towards hepatitis C's elimination.

The time of cure: hepatitis C treatment and the matter of reinfection among people who inject drugs

Australia has made considerable progress towards the public-health 'elimination' of the hepatitis C virus. Nonetheless, reinfection remains a key challenge, with little understanding regarding the lived complexities of post-cure life among people who inject drugs. Our analysis examines reinfection through the lens of 'time', a largely overlooked and under-utilised analytical concept within the field of hepatitis C. Drawing on qualitative data from a study examining treatment outcomes and reinfection, our analysis concentrates on three participant accounts or 'cases'. Working within a new materialist framework, we combine recent social science scholarship which, firstly, posits cure as a socio-material 'gathering', and secondly, proposes a 'futurology' of hepatitis C and its treatment. We found participant accounts troubled the neat binary of pre- and post-treatment life, instead detailing the challenges of remaining virologically safe while navigating complex, local life-worlds. Rather than a singular, post-treatment future instantiated by cure, participants described the fluid, emergent nature of what we might describe as 'lived' or 'embodied' time, including multiplicities of becoming in a perpetual present. We conclude that our understanding of reinfection needs to move beyond its current, narrow biomedical conception and organising temporal logic to honour and incorporate complexity in practice.

In search of a 'good number': knowledge controversy and population estimates in the endgame of hepatitis C elimination

We explore the contentious life of a metric used to assess a country's progress in relation to global disease elimination targets. Our topic is hepatitis C elimination, and our context is Australia. A fundamental metric in the calculation of progress toward hepatitis C elimination targets, as set by the WHO, is the population prevalence of people living with hepatitis C. In Australia, this modelled estimate has generated some controversy, largely through its repeated downsizing as an effect of calculus. The 2015 baseline population estimate in Australia, from which measures of current elimination progress are assessed, has reduced, over time, by around 30%. Informed by a social study of science approach, we used qualitative interviews with 32 experts to explore the knowledge controversy. The controversy is narrated through the core concerns of 'scale' and 'care', with narratives aligning differently to imaginaries of 'science' and 'community'. We trace how constitutions of 'estimate' and 'number' circulate in relation to 'population' and 'people', and as affective values. We show how enactments of estimates and numbers materialise hepatitis elimination in different ways, with policy implications. The event of the knowledge controversy opens up the social and political life of enumerations-for science and community-inviting deliberation on how to make 'good numbers' in the race to eliminate hepatitis C.

'There's too much power in this number. It's freaking the whole response out': The views of key informants on evidence and targets to achieve hepatitis C elimination goals in Australia

Enumeration of disease is a key management tool. Setting of targets, like for hepatitis C elimination, have deep meaning and effect. We use the case of elimination in New South Wales (NSW), Australia to examine key informants' understandings of the use of targets, and the evidence that informs them, to drive action in elimination. Twenty-eight key informants working in NSW, elsewhere in Australia and internationally in high-income countries participated in a semi-structured qualitative interview in 2022. Analysis was informed by scholarship calling for examination of the ways in which science constructs what is thought possible in action. Participants pointed to the power of quantified evidence and targets and their complex effects, and questioned the usefulness and certainty derived from these at the "pointy end" of elimination. Although a range of targets exist in global and local strategies, reaching testing targets was the assumed solution to achieving elimination. Achieving elimination was thought to require "off piste" and experimental approaches that went beyond available evidence. The different types of work that participants felt necessary for late-stage elimination may require additional metrics to explain return on investment ratios. What threshold would be used to reduce efforts in elimination was a major concern. These data indicate that understandings of the evidence underpinning elimination targets and how to achieve them are far from settled. At this point, elimination efforts may need to rely on locally produced and community-driven evidence and shift from evidence-based to evidence-making paradigm.

Evaluation of the use of modelling in resource allocation decisions for HIV and TB

INTRODUCTION

Globally, resources for health spending, including HIV and tuberculosis (TB), are constrained, and a substantial gap exists between spending and estimated needs. Optima is an allocative efficiency modelling tool that has been used since 2010 in over 50 settings to generate evidence for country-level HIV and TB resource allocation decisions. This evaluation assessed the utilisation of modelling to inform financing priorities from the perspective of country stakeholders and their international partners.

METHODS

In October to December 2021, the World Bank and Burnet Institute led 16 semi-structured small-group virtual interviews with 54 representatives from national governments and international health and funding organisations. Interviews probed participants' roles and satisfaction with Optima analyses and how model findings have had been used and impacted resource allocation. Interviewed stakeholders represented nine countries and 11 different disease programme-country contexts with prior Optima modelling analyses. Interview notes were thematically analysed to assess factors influencing the utilisation of modelling evidence in health policy and outcomes.

RESULTS

Common influences on utilisation of Optima findings encompassed the perceived validity of findings, health system financing mechanisms, the extent of stakeholder participation in the modelling process-including engagement of funding organisations, sociopolitical context and timeliness of the analysis. Using workshops can facilitate effective stakeholder engagement and collaboration. Model findings were often used conceptually to localise global evidence and facilitate discussion. Secondary outputs included informing strategic and financial planning, funding advocacy, grant proposals and influencing investment shifts.

CONCLUSION

Allocative efficiency modelling has supported evidence-informed decision-making in numerous contexts and enhanced the conceptual and practical understanding of allocative efficiency. Most immediately, greater involvement of country stakeholders in modelling studies and timing studies to key strategic and financial planning decisions may increase the impact on decision-making. Better consideration for integrated disease modelling, equity goals and financing constraints may improve relevance and utilisation of modelling findings.

'Ending AIDS' between comparison and commensuration and the role of global health indicators

The use of targets and indicators in global health has become ubiquitous within global health and disease elimination programmes. The drive to 'end AIDS' has become a global flagship endeavour, including nation-states, donor organisations, NGOs, pharmaceutical companies, medical researchers, and activists. Almost synonymous with the campaign of ending AIDS is UNAIDS' 90-90-90 targets. Beyond indicators' role in neoliberal global health, an essential aspect of indicators and quantitative metrics is their ability to provide a basis for measurements and comparability across time and between different actors and entities. These processes are based on what has been called, commensuration, visual simplification, and serialisation. This article seeks to provide an account of how we can think about indicators in the drive to end AIDS as doing work that is contingent upon commensuration, simplification, and serialisation. The argument is that by attending to issues of commensuration, visual simplification, and serialisation we are better able to see how we risk erasing and foreclosing other forms of conceptualising what the end of AIDS could be. Logics of quantification risks erasing and foreclosing other qualitative aspects of the HIV epidemic as well as obscuring various epistemological tensions inherent in counting towards the end of AIDS.

'I'm not hep C free': afterlives of hepatitis C in the era of cure

Since the advent of more effective, new-generation treatment for hepatitis C, immense resources have been devoted to delivering cure to as many people with the virus as possible. The scale-up of treatment aims to prevent liver disease, liver cancer and onward transmission of hepatitis C, but social research shows that people also approach treatment with its social promises in mind, including the hope that it might reduce or eradicate stigma from their lives. Such hopes reflect broader ideas about medical cure, which is seen as an end point to illness and its effects, and capable of restoring the self to a (previous) state of health and well-being. But what does cure mean among people for whom treatment does not produce an end to the social effects of a heavily stigmatised disease? While new treatments promise to eliminate hepatitis C, accounts of post-cure life suggest that hepatitis C can linger in various ways. This article draws on interviews with people who have undergone treatment with direct-acting antivirals (n=30) in Australia to explore the meanings they attach to cure and their experiences of post-cure life. We argue that dominant biomedical understandings of cure as an 'ending' and a 'restoration' can foreclose insight into the social and other effects of illness that linger after medical cure, and how individuals grapple with those afterlives. Drawing on recent conceptual re-framings of cure from medical anthropology and disability studies, we suggest that thinking at the limits of 'curative reason' helps to better address the afterlives of chronic illness. In the case of hepatitis C, reconceptualising cure could inform improved and less stigmatising ways of addressing people's post-cure needs. And in the era of hepatitis C elimination, such reconceptualisation is increasingly important as the cohort of people undergoing treatment and cure expands worldwide.

Modeling as Visioning: Exploring the Impact of Criminal Justice Reform on Health of Populations with Substance Use Disorders

In the context of historic reckoning with the role of the criminal-legal system as a structural driver of health harms, there is mounting evidence that punitive drug policies have failed to prevent problematic drug use while fueling societal harms. In this explainer article, we discuss how simulation modeling provides a methodological framework to explore the potential outcomes (beneficial and harmful) of various drug policy alternatives, from incremental to radical. We discuss potential simulation modeling opportunities while calling for a more active role of simulation modeling in visioning and operationalizing transformative change.

Highlights

This article discusses opportunities for simulation modeling in projecting health and economic impacts (beneficial and harmful) of drug-related criminal justice reforms.We call on modelers to explore radical interventions to reduce drug-related harm and model grand alternative futures in addition to more probable scenarios, with a goal of opening up policy discourse to these options.

Undoing elimination: Modelling Australia's way out of the COVID-19 pandemic

In the middle of 2020, with its borders tightly closed to the rest of the world, Australia almost achieved the local elimination of COVID-19 and subsequently maintained 'COVID-zero' in most parts of the country for the following year. Australia has since faced the relatively unique challenge of deliberately 'undoing' these achievements by progressively easing restrictions and reopening. Exploring the role of mathematical modelling in navigating a course through the pandemic through qualitative interviews with modellers and others working closely with modelling, we argue that each of these two significant phases of Australia's COVID-19 experience can be understood as distinct forms of 'model society'. This refers at once to the society enacted through the governance of risk, and to the visions of societal outcomes - whether to be sought or to be avoided - that are offered up by models. Each of the two model societies came about through a reflexive engagement with risk facilitated by models, and the iterative relationship between the representations of society enacted within models and the possibilities that these representations generate in the material world beyond them.

'Not just one box that you tick off' - Deconstructing the hepatitis C care cascade in the interferon-free direct acting antiviral era from the client perspective

BACKGROUND

To achieve hepatitis C viral (HCV) elimination targets set by the World Health Organisation, pillars of the HCV care cascade are often referenced to track progress. The aim of this qualitative study was to explore the limitations of the care cascade framework through the real-world accounts of 'HCV journeys' among people who inject drugs (PWID), with particular attention to the intersection of PWID agency and structural determinants in the healthcare system.

METHODS

An in-depth analysis was conducted on five case studies to better understand participant experiences 'behind the cascade pillars'. The five case studies were drawn from the ETHOS Engage cohort as exemplars of the real-world complexities of people's HCV cascade journeys. Inclusion criteria for the qualitative study were participant has voluntarily signed the informed consent form, aged ≥18 years, HCV antibody positive by self-report, clients of selected sites participating in the ETHOS Engage cohort, and sufficiently proficient in English to participate in an interview. Thirty-four semi-structured interviews were conducted with participants who had received or had not received HCV treatment to identify barriers and facilitators to HCV care.

RESULTS

Participants 'housed' at the 'HCV RNA diagnosed pillar' (n = 2; Will; Julie) reported withholding their HCV serostatus in certain healthcare settings for fear that disclosure would lead to discriminatory decision-making from their treating physician. among participants who had completed treatment (n = 3; Corey; John; Nora) two reported still being unsure of their HCV status >6 months post-treatment. Ongoing feelings of frustration and shame were expressed in this 'post-cure care pillar' due to a perceived lack of quality care from clinic services and continued uneasiness when discussing drug use and reinfection while receiving opioid agonist treatment (OAT). Both case 'categories' described often tenuous therapeutic relationships with their physicians and recommended task-shifting to nurses and trusted case workers for ongoing care.

CONCLUSION

The care cascade provides a linear, two dimensional snapshot of clinical targets. Our findings illuminate structural barriers not visible behind its 'static' pillars, presenting insights into experiences among PWID otherwise dismissed as 'disengaged' or 'lost to follow-up'.

New directions for participatory modelling in health: Redistributing expertise in relation to localised matters of concern

Participatory modelling seeks to foster stakeholder engagement to better attune models to their decision-making and policy contexts. Such approaches are increasingly advocated for use in the field of health. We review the instrumental and epistemological claims made in support of participatory modelling approaches. These accentuate participatory models as offering a better evidence-base for health policy decisions. By drawing attention to recent modelling experiments in a sector outside of health, that of water management, we outline a different way of thinking about participation and modelling. Here, the participatory model is configured in relation to matters of 'knowledge controversy', with modelling constituted as an 'evidence-making intervention' in relation to the making of science and expertise. Rather than presenting participatory models as an improved technical solution to addressing given policy problems within an evidence-based intervention approach, models are alternatively potentiated as sites for the redistribution of expertise among actor networks as they seek to engage politically in a matter of concern. This leads us to consider possible new directions for participatory modelling in the field of health.

Futures-oriented drugs policy research: Events, trends, and speculating on what might become

One concern in the field of drugs policy is how to make research more futures-oriented. Tracing trends and events with the potential to alter drug futures are seen as ways of becoming more prepared. This challenge is made complex in fast evolving drug markets which entangle with shifting social and material relations at global scale. In this analysis, we argue that drugs policy research orientates to detection and discovery based on the recent past. This narrows future-oriented analyses to the predictable and probable, imagined as extensions of the immediate and local present. We call for a more speculative approach; one which extends beyond the proximal, and one which orientates to possibilities rather than probabilities. Drawing on ideas on speculation from science and technology and futures studies, we argue that speculative research holds potential for more radical alterations in drugs policy. We encourage research approaches which not only valorise knowing in relation to what might happen but which conduct experiments on what could be. Accordingly, we trace how speculative research makes a difference by altering the present through making deliberative interventions on alternative policy options, including policy scenarios which make a radical break with the present. We look specifically at the 'Big Event' and 'Mega Trend' as devices of speculative intervention in futures-oriented drugs policy research. We illustrate how the device of Mega Trend helps to trace as well as to speculate on some of the entangling elements affecting drug futures, including in relation to climate, environment, development, population, drug production, digitalisation, biotechnology, policy and discourse.

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.

Modelling the pandemic: attuning models to their contexts

The evidence produced in mathematical models plays a key role in shaping policy decisions in pandemics. A key question is therefore how well pandemic models relate to their implementation contexts. Drawing on the cases of Ebola and influenza, we map how sociological and anthropological research contributes in the modelling of pandemics to consider lessons for COVID-19. We show how models detach from their implementation contexts through their connections with global narratives of pandemic response, and how sociological and anthropological research can help to locate models differently. This potentiates multiple models of pandemic response attuned to their emerging situations in an iterative and adaptive science. We propose a more open approach to the modelling of pandemics which envisages the model as an intervention of deliberation in situations of evolving uncertainty. This challenges the 'business-as-usual' of evidence-based approaches in global health by accentuating all science, within and beyond pandemics, as 'emergent' and 'adaptive'.