Why lockdown? Simplified arithmetic tools for decision-makers, health professionals, journalists and the general public to explore containment options for the novel coronavirus

Gerry Killeen; Samson Kiware

For all but the most expert specialists, the silent early phase of an epidemic, when there is still time to contain it, is often imperceptible and difficult to grasp the significance of. This is especially true for pathogens like novel coronavirus-2019 (COVID-19) that largely exhibit only mild symptoms, if any, 1-23 that are non-specific and difficult to distinguish from other, more common illnesses. 24 Currently, half the world's population is already under lock-down of some kind, meaning vertically enforced and severe restrictions of movement, and the remainder will have to follow if the ongoing COVID-19 virus pandemic is to be contained. Faced with such brutally difficult decisions, it is essential for policy-makers, health professionals, journalists and the general public that as many people as possible understand (1) why lock-down interventions represent the only realistic way for individual countries to contain their national-level epidemics before they turn into public health catastrophes, (2) why these need to be implemented so early, so aggressively and for such extended periods, and (3) why international co-operation to conditionally re-open trade and travel between countries that have successfully eliminated local transmission represents the only way to contain the pandemic at global level.