Speaker
Description
Strategies to mitigate an infectious disease outbreak can be focused or unfocused. Focused interventions (FI) aim to limit transmission from known or likely infectious individuals (e.g., quarantining contacts). Unfocused interventions (UI) affect all individuals irrespective of infection status by lowering the effective contact rate (e.g., lockdowns or universal masking). The costs of FI typically scale with disease prevalence, whereas the costs of UI are largely independent of prevalence but increase rapidly with intervention severity.
We investigate the optimal allocation of resources when both intervention types are available. Using compartmental epidemic models, we analyze optimality for (i) the final epidemic size and (ii) the peak epidemic height, considering cases where isolated infected individuals do or do not contribute to the peak. We consider both a fixed per-period budget and a fixed total budget for the epidemic.
For final size minimization, minimizing the reproduction number is optimal for a fixed per-period budget. With a fixed total budget, interventions should be applied when they yield the largest reduction in infectious output. If FI costs scale linearly with prevalence, timing is irrelevant as long as the budget is used. UI should be applied around the peak. To minimize peak height, FI should start early, while UI should be applied around the peak. Qualitative results are robust to disease characteristics and intervention effectiveness.
