NHS figures show 850 people were alerted by the app in the seven days to June 30. For the following seven days, to July 7, the figure was 1,443.
At Prime Minister’s Questions on July 7, Labour leader Keir Starmer warned that large numbers of people could soon be asked to self-isolate, with major consequences for businesses.
He said: “How many people will be asked to self-isolate if there are 100,000 cases a day?”
Adur and Worthing also saw increases in the number of people receiving alerts from the Covid app.
There was a 90.7 per cent increase in Adur, with 845 people ‘pinged’ in the seven days to July 7, compared to 443 the week before.
Worthing saw a jump of more than 128 per cent – 1,238 people were ‘pinged’ in the seven days to July 7. The number was 541 the previous week.
Other nearby local-authority areas also saw increases in the number of people alerted.
Horsham saw the number of ‘pings’ rise from 737 to 1,385 – an 87.9 per cent increase – while Chichester’s went up by 40 per cent, from 625 to 875.