The most important single thing we have learnt from Covid-19 is how much damage may be done by a relatively mild pandemic by long-term historical standards. To call it mild is not to belittle the suffering it has caused, and will continue to cause, before an effective vaccination programme is rolled out and sustained globally. But Covid-19 has demonstrated a social and economic vulnerability far greater than experts imagined. It is important to understand why this is the case and learn how to manage the impact of such diseases better in future.
In a recent paper, David Cutler and Lawrence Summers of Harvard estimate the total cost of Covid-19 to the US alone at $16tn. This amounts to 75 per cent of a year’s US gross domestic product. Almost half of this is the cumulative value of lost GDP estimated by the non-partisan Congressional Budget Office. The rest is the cost of premature death and impairment of physical and mental health, according to values customarily used for the world’s richest big economy. The total cost is, they judge, four times that of the recession after the 2008 financial crisis. If the cost to the world were also to be 75 per cent of annual GDP, it would be around $96tn, at purchasing power parity exchange rates. That is almost certainly an overestimate. Nevertheless, the cost is huge.
So far, the global death toll of Covid-19 is estimated at 1.4m. Deaths are now running at a little under 10,000 a day or about 3.5m a year. If this were maintained, cumulative deaths over the first two years might reach close to 5m, or just over 0.06 per cent of the global population. To put this in context, the Spanish flu, which emerged in 1918, lasted 26 months and cost somewhere between 17m and 100m lives, or between 1 and 6 per cent of the then global population. A comparable death toll for Covid-19 today would be between 80m and more than 400m. Some pandemics, notably the Black Death in the 14th century, have been far more lethal even than Spanish flu.