Integrated Quantification of the Health and Economic Impacts of Differing Strategies to Control the COVID-19 Pandemic

Abstract

Background: Countries can decide between one of three COVID-19 control strategies: 1) elimination (e.g., some island countries); 2) suppression, to low infection rates; 3) or mitigation, as per pandemic influenza strategies with ensuing herd immunity. This paper quantifies the health (direct COVID-19 impact, and indirect through unemployment onto self-harm and road traffic crash) and cost (health system and societal) consequences for these strategies across Australia, New Zealand (NZ) and Sweden. Methods: We used proportional multistate lifetable (PMSLT) models for each country, with mortality and morbidity data from the Global Burden of Disease Study and health system expenditure from country-specific sources. Feeding into the PMSLT were monthly SARS-CoV-2 infection rates (0.1%/2.5%/60% for elimination/suppression/mitigation by 18 months), and anticipated changes in unemployment rates that generated changes in suicide/self-harm and RTC injury rates. For Australia and NZ, we also estimated fixed health system costs by strategy and GDP loss for societal costing. We used a 3% per annum discount rate, over a 20-year time horizon. FINDINGS Compared to the pre-pandemic baseline, health adjusted life year (HALY) losses were 15.0/ 11.0/ 23.0 per million population under elimination for Australia/ NZ/ Sweden, 1,540/ 1,500/ 1,820 per million for suppression, and 19,800/ 19,500/ 22,400 for mitigation. For Australia and NZ, the optimal policy from a health system perspective was mitigation up to a US$20,000 willingness-to-pay (WTP) per HALY gained. For higher WTP, elimination (or suppression if elimination is not feasible) was favoured. From a societal perspective (health system costs plus GDP losses), mitigation was optimal up to US$240,000 per HALY, then elimination (or suppression). Interpretation: This modelling analysis suggests that elimination or suppression is optimal across the usual range of WTP from a health system perspective in high-income countries (HICs). But from a societal perspective, mitigation is favoured unless a HALY is valued at over US$240,000. Funding Statement: Health Research Council of New Zealand (16/443) for core model development). Strategic and COVID-19 specific funding for this research was provided by the Melbourne School of Population and Global Health, University of Melbourne. Carvalho is supported by the University of Melbourne McKenzie Postdoctoral Fellowship. Declaration of Interest: None.