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

Abstract

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.

“Like a pickle that’s been unpickled”: Emotional, identity and behavioural transformations throughout hepatitis C treatment

“…Since their inception, DAA therapies have been heralded and promoted as a ‘cure’ for hepatitis C. Whilst treatments are curative for the vast majority of people living with hepatitis C, the concept of cure has been entrenched in a biomedical discourse [ 29 , 39 ]. More broadly, the motif of cure has been critiqued for being predicated on returning an individual to their pre-illness state of health, which obscures the personal, social and emotional aspects of illness [ 40 ].…”

Futuring a world without disease: visualising the elimination of hepatitis C

“…This 'race to elimination' is not unique to the NOhep campaign. It is rhetoric increasingly invoked within the hepatitis C field, as nation states are positioned against each other as assessments are made about who might be 'on track' and who is 'lagging behind' in meeting strategic elimination targets (Rhodes & Lancaster, 2020;WHO, 2019).…”

“…Within this suite of practices, global targets do particularly significant work to give a sense of accuracy and control over diffuse and imagined disease elimination futures, by making the problem of disease elimination manageable, recognisable, enumerated and therefore able to be acted upon (Lancaster et al, 2019;Merry, 2016;Rhodes & Lancaster, 2020;Shore & Wright, 2015). As technologies of governing, global elimination targets are integral to how "the end" (Gane, 2014) of hepatitis C is performed, delimiting how hepatitis C futures might be imagined (Lancaster et al, 2019).…”

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

“…Enumerated projections are thus an important mode of evidence‐making in an anticipatory regime which orientates governance of the present in relation to the future (Adams et al, 2009 ; Arkut et al, 2019 ). Such is the pervasive presence of enumerated projections and numerical targets in the field of global health, that it is difficult to see how a science of viral elimination might be made otherwise (Rhodes & Lancaster, 2021 ).…”

“…Treatment‐as‐prevention then shifts again in its enactments to potentiate the elimination of hepatitis C at the population level. The transformation of treatment‐as‐prevention to treatment‐as‐elimination is enabled by assemblages of viral elimination promise which incorporate the models and their projections as actors alongside pharmaceuticals, clinical trials, implementation science, national policies, public health discourses, community advocacy and global strategies (Rhodes & Lancaster, 2021 ). Particularly significant are efforts to project the treatment scale‐up required to achieve global viral elimination targets (Fraser et al, 2018 ; Gountas et al, 2018 ; Hagan et al, 2013 ; Heffernan et al, 2019 ; Hellard et al, 2012 , 2014 ; Innes et al, 2015 ; Kwon et al, 2019 ; Martin et al, 2013b , 2016 , 2017 ; Razavi et al, 2017 ; Scott et al, 2017 , 2018 ; Ward et al, 2018 ).…”