Data suggests people are reluctant to pass on the details of possible contacts outside their own household, Prof Fraser said, adding: “About two thirds of the contacts are reported in the household, and we don’t know exactly why that is.”
Last month, the Government introduced a new self-isolation coronavirus grant for people in work on low incomes, a £500 lump sum payment if they cannot work from home and are required to self-isolate.
But Prof Fraser suggested that, for many people, the financial cost of self-isolating was still too high, saying: “The majority of people getting infected are quite young. There is a degree of being fed up with the situation. There are also a lot of people who maybe don’t isolate because the cost for their livelihoods is very difficult.
“However, I think it,s important to note that the infection this time around is concentrated in certain areas and among certain groups, rather than across the country. That suggests most people are still doing their bit.”
This week, Prof Fraser and his team published a study showing that a trial version of the NHS app on the Isle of Wight appeared to have led to a substantial reduction in the ‘R’ rate, even though that version of the app was later abandoned.
“There was very clear community engagement between the local council, the local MP, the local radio, the NHS. People bought into it,” he said. “What we’ve learned from previous epidemics is that you need a clear repetition of messages for people to take action. However, the public debate is quite erratic at the moment.
“To get people to respond, you need clarity of message and clarity of strategy.”
A Department of Health spokesman said: “The target has always been to expand capacity to 500,000 tests a day by the end of October, and we remain on track to deliver this.
“NHS Test and Trace is the biggest testing system per head of population of all the major countries in Europe, and we are processing tests at an unprecedented rate – 265,000 a day on average over the last week. It is working to break chains of transmission, with over 900,000 people who may otherwise have unknowingly spread coronavirus contacted and told to isolate.”