There has not been a lot of good news lately. But with the discharge of Boris Johnson from hospital on Sunday, and statements that the “peak” strain on the National Health Service would be over the Easter period, you might be under the impression that the storm is passing, and the Covid-19 pandemic will soon be a memory.

Fueling this mood are reports from studies of communities already hit by the pandemic. At long last we are beginning to see the results of work looking for…