As the outbreak spread there, beginning 22 February 2020, a "cordon sanitaire" was imposed on a group of at least 10 different municipalities in Northern Italy, effectively quarantining more than 50,000 people. This followed a second day when the declared detected cases leapt enormously (the period from 21 to 23 February saw daily increases of 567%, 295% and 90% respectively). A week later the rate of increase of cases in Italy was significantly reduced (the period from 29 February to 4 March saw daily increases of 27%, 50%, 20%, 23%, and 23%).