Time-variant strategies for optimizing the performance of non-pharmaceutical interventions (NPIs) in protecting lives and livelihoods during the COVID-19 pandemic

Wei Aun Yap; Dhesi Baha Raja

At time of writing there is no proven vaccine or other medical breakthrough in the prevention or treatment of COVID-19. Societies are hence faced with a difficult choice between two broad paths. The first path is to strongly suppress the outbreak and eliminate local transmission, leaving the population relatively unravaged by COVID-19 and its associated morbidity and mortality, but fully susceptible to SARS-CoV-2. NPI measures required to attain and preserve this paradigm are substantive and are not short term. They will have major implications on society, the economy, and other aspects of health such as mental health and emergency management of noncommunicable diseases. If a proven and accessible vaccine then becomes available, population herd immunity can be developed through immunization rather than infection. This first path is not the focus of this paper as an exit from NPI is antithetical. The second path leads to a population which is no longer susceptible to SARS-CoV2 through the attainment of herd immunity by infection, implying that a large proportion of the population will be exposed to COVID-19 morbidity and mortality on-route to this destination. The goal of NPIs in this context is to keep the burden of COVID-19 cases within the capacity of the health system. However, not all NPIs are created equal in terms of performance against epidemiological outcomes measures and non-epidemiological outcomes, as explored through simulations in this paper.