Only one third of people involved in the UK's first contact tracing scheme agreed to self-isolate, the organisers have revealed.
A retired doctor who set up the scheme in Sheffield said the issues with the pilot programme posed a "major challenge" for the government's test and trace programme, launched on Friday.
The DIY contact tracing team, launched by retired doctors and public health officials in April as the Sheffield Community Contact Tracers, said they had struggled in particular to persuade health and care workers to self-isolate.
The team initially identified 58 contacts from 10 coronavirus cases. Some 19 were named, given advice, and followed for the recommended 14 day quarantine. One became ill.
However, the 10 initial cases were either unable or unwilling to provide the details of the remaining 39 contacts. Of these, 29 worked for the NHS or a care home provider. Their employers were contacted and given the self-isolation advice, but while some said they would pass on information to staff, they did not provide further details to allow for follow-up. Others refused to cooperate.
The scheme's Dr Bing Jones said the scheme showed some positives, including the fact that they managed to catch one case who could have gone on to infect many more. But for many of the NHS or care home workers in the scheme, there had been problems, he said.
"They generally said 'we'd like to help but I discussed it with my manager and my manager says no'."
He added that "this is a major challenge for the government".
Dr Tom Wingfield, senior lecturer at Liverpool School of Tropical Medicine, said: “The preliminary data...confirms what tuberculosis (TB) contact tracing teams around the UK already know: contact tracing is not easy."
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