Given What We’re Losing in GDP, We Should Be Spending Far More to Develop Tests

When it comes to crafting foreign policy, designing anti-poverty programs or implementing measures to combat climate change, economists have an understandable tendency to feel as though the economic aspects of the debate receive short shrift. The opposite is true when it comes to the pandemic. If anything, the United States is in danger of overemphasizing the impact of the crisis on the economy — and massively underinvesting in the health measures that are ultimately most important.

We are embarked on a policy path of opening things up without major complementary measures, an approach based more on wishful thinking than on logic or evidence. In guidance issued last month, the Trump administration stated this relaxation should only begin when the number of new cases daily had declined for 14 days. This criterion has not been met for the country as a whole or in many states, yet reopening has begun.

A simple calculation illustrates why this path is so dangerous. The most important parameter for understanding an epidemic is what epidemiologists label R0 (R-nought) — the number of people infected by a single individual with the virus. If R0 is greater than 1, an epidemic explodes; if it is less than 1, it diminishes and eventually ceases to be a problem. Experts estimate that before lockdown R0 was about 2.5, which is why lockdown was necessary. They now estimate, in part because case counts have been stable, that R0 is a bit below 1 — perhaps 0.9 or, on an optimistic view, 0.8.

Basic but grim arithmetic implies that if we move from lockdown even 20 percent of the way back to normal life, the epidemic will again be potentially explosive. (For example, if we are currently at an R0 of 0.9, and assuming that the R0 without any distancing is 2.5, then returning to 20 percent of normal would take the R0 to 1.22, clearly in the danger zone.) This is very worrying as the president and many other political leaders seem to be encouraging substantial reversals in lockdown policies.

It’s conceivable this will work out, at least in the short run. For a few months, summer heat and humidity may reduce transmissibility. The virus may mutate in benign ways. The population that has not yet been infected may be less susceptible on average to the virus and less contagious when they catch it.