SOAVE, Italy — A new study quantifying the hidden toll from coronavirus in the province of Bergamo, at the epicenter of Italy’s epidemic, has found that the number of deaths linked to the virus is double the official tally.

The study by the daily L’Eco di Bergamo with the InTwig data analysis agency puts the number of virus deaths last month at 4,500, compared with the official toll of 2,060, in the province of 1.1 million people.