Bergamo and the enigma of Covid-19

There seems to be only one certainty with Covid-19: that every day we will be bombarded with fresh evidence and scientific opinion that is contradictory and leaves us a long, long way from understanding this disease. Just when it seemed that antibody tests were indicating infection rates of no more than 10 per cent in the worst-affected countries and no greater than 20 per cent in the worst-affected cities, along comes a study which points to vast numbers of infections. This morning, the public health agency in the Northern Italian city of Bergamo – the epicentre of the Italian outbreak in March – reports that a random sample of 9,965