PProfessor Christophe Fraser, an infectious disease epidemiologist at the University of Oxford, said the NHS Test and Trace app only tells recipients to self-isolate if they are at risk of becoming infected, as a result of criticism that he is interviewing too wide a range of people.
The expert who advised the Department of Health on testing and traceability told BBC Radio 4’s Today program: “If you check in at a location where there has been an outbreak, you basically get a warning. which tells you that you have been there and informs you you should either be careful or, if it is a major outbreak, advise you to take a test – so there is no need to isolate .
“The obligation to isolate comes if you have come into close contact, and we have shown in our analysis that this is really close contact – it is not six to eight meters, it is the kind of contact that gives a reasonable probability that you may have been infected and become a case – so if people use the app in that way, we slow down infections. “
Asked whether those who have been doubly stung should be exempt from self-isolation after being boned by the app, Professor Fraser said: “I think one of the halfway proposals which would be a good way forward – I agree with the policy needs to be reviewed in light of the data on vaccine effectiveness – is for daily contact testing.
“When you get a close contact notification, the one that says you’ve been close to someone for an extended period of time, the envisaged possibility is that you will be tested for seven days after being pinged by the app.
“There is a pilot, there is a test, people will be looking at the data very closely, but I think it would be a very promising way to reduce the number of disruptions for people.”