Next week Parliament will debate what should happen when the second Covid-19 lockdown comes to an end on 2 December. Yesterday’s blog showed that even with rapid rollout of a highly effective Covid-19 vaccine, a return to September-style restrictions after 2 December, with no other mitigation, may well trigger a third wave of the virus and many thousands more deaths. Parliamentarians, and ministers, therefore need to consider alternative options for managing the pandemic until well into 2021.
Using our downloadable interactive Covid cost model, here we model three policy options, all based on a pace of vaccine rollout that sees almost 7 million people vaccinated by the end of March. You can download the model here and develop your own variants (for full functionality you need to be signed in to Microsoft and open the model in the desktop app).
Scenario 1 involves extending the lockdown for three weeks, from 3 December until Christmas Eve, and then reverting to light, September-style restrictions.
Scenario 2 models a slight easing of restrictions on 3 December, but then retaining those relatively stringent rules well into 2021. This might involve keeping hospitality settings closed while opening retail, for example.
Scenario 3 represents a version of the strategy TBI recently called for in our publication ‘Light at the end of the tunnel’: expanding mass testing to raise the rate of detection of asymptomatic carriers, improving tracing and isolation rates, and rolling out therapeutics that reduce the infection fatality rate (see below for further detail on the assumptions).
The chart shows the total cost of each option broken down by Covid and non-Covid health costs, and economic costs in terms of lost GDP from November to May, relative to there being no Covid at all. The first bar shows the baseline option of reverting to September-style restrictions on 3 December. In this case a third wave causes many new fatalities and the resulting fear factor creates a damaging drag on economic activity.
All three of the scenarios are less costly than this baseline option, not only in the number of lives lost but also in terms of the economic impact. Extending the lockdown, Scenario 1, saves lives and jobs compared to not doing so. But a more limited easing, with restrictions in place for longer - Scenario 2 - looks to be a better bet.
The best option, if it can be achieved, would be to combine substantial easing with a significantly improved testing and tracing regime, and the deployment of effective therapeutics (Scenario 3). If ambitious goals for these aspects of the strategy can be achieved from the start of 2021, then we could return to September-style restrictions from December 3 and minimise both economic and health costs.
The chart below provides estimates of the total number of additional Covid deaths that might occur under each scenario. The pattern mirrors the total cost chart, showing that the baseline option could result in three times the loss of life of Scenarios 2 or 3.
All of these results depend, of course, upon the assumptions made. The purpose of our model is not to provide definitive answers so much as to elucidate the trade-offs between different courses of action and clarify the assumptions made by their proponents.
Despite the recent good news then, we’re nowhere near out of the woods yet. For those taking difficult decisions on the suppressions strategy next week, what we can say is that unless there is a step change in testing, tracing and treatment soon, we may either have to live with continued restrictions for some time yet or see a third costly wave of Covid-19 before the vaccine cavalry arrives.
Assumptions for Scenario 3 apply from 1 January 2021:
Detection rate of cases rises to 70% through mass testing
Proportion of cases providing details of contacts rises to 80% (from 64% in late October)
Tracing success rate rises to 80% (from 58% in late October)
Compliance rises to 50% (from less than 20% in July and August)
The infection fatality rate is assumed to halve from 0.65% to 0.325%