Post-lockdown abatement of COVID-19 by fast periodic switching

Abstract

COVID-19 abatement strategies have risks and uncertainties which could lead to repeating waves of infection. We show—as proof of concept grounded on rigorous mathematical evidence—that periodic, high-frequency alternation of into, and out-of, lockdown effectively mitigates second-wave effects, while allowing continued, albeit reduced, economic activity. Periodicity confers (i) predictability, which is essential for economic sustainability, and (ii) robustness, since lockdown periods are not activated by uncertain measurements over short time scales. In turn—while not eliminating the virus—this fast switching policy is sustainable over time, and it mitigates the infection until a vaccine or treatment becomes available, while alleviating the social costs associated with long lockdowns. Typically, the policy might be in the form of 1-day of work followed by 6-days of lockdown every week (or perhaps 2 days working, 5 days off) and it can be modified at a slow-rate based on measurements filtered over longer time scales. Our results highlight the potential efficacy of high frequency switching interventions in post lockdown mitigation. All code is available on Github at https://github.com/V4p1d/FPSP_Covid19. A software tool has also been developed so that interested parties can explore the proof-of-concept system.

Modeling COVID-19 Nonpharmaceutical Interventions: Exploring periodic NPI strategies

“…Figure 3 demonstrates that using a small set of alternative measures can support those decisions and reveal pareto-dominated strategies. Strategy F-3, our baseline strategy, is pareto-dominated by a wide range of strategies that oscillate between the NPI level of 5 and 1, using many periods, which is in line with prior research [5].…”

“…Fixed NPIs are not, however, the only way to control the pandemic. Alternatively, one could use periodic strategies to curb transmission [11]. A periodic NPI can represent a strategy wherein society goes into more severe periods of NPIs then relaxes to lower levels of stringency.…”

“…First, we provide only an overview of our model structure that is required for understanding our results. Then, we briefly analyze a set of illustrative scenarios including periodic and fixed strategies, seeking to find if periodic strategies found to be potentially useful by other modelers [11] also produce similar results in our model. Finally, we provide detailed information on our mathematical model and present sensitivity analyses.…”

“…In this paper, we consider periodic NPI strategies. Recent research has demonstrated that high-frequency periodic NPIs [5] have the potential to mitigate COVID-19 resurgences while providing more predictability and alleviating the damaging effects on economic activity and social well-being. We use our updated model to explore if a periodic strategy could have provided benefits compared to fixed strategies that would keep R t close to one.…”

How to coordinate vaccination and social distancing to mitigate SARS-CoV-2 outbreaks

“…Nonpharmaceutical measures were used to attain a stable equilibrium with low case numbers in [24]. In [25], the authors propose an on-off (also called bang-bang) social distancing policy for mitigating a second wave. The subject of optimal vaccination has also been considered [26, 27].…”