Summer chaos predicted as up to 1.6m in England told to isolate in a week

Government says its Covid app is unlikely to be adjusted to make it less sensitive for weeks

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Up to 1.6 million people in England have been told to isolate in a single week, Guardian analysis has found as the government said the Covid app is unlikely to be changed for weeks.

The number of new UK coronavirus cases climbed to 48,553 on Thursday - the highest since mid-January and the start of the third lockdown - with the upward curve showing no signs of abating, raising fears of a summer of chaos as businesses and households are hit by self-isolation. Sixty-three people were reported on Thursday to have died from the virus.