In its first week of operation, England’s coronavirus contact tracing scheme was unable to reach a third of the people who tested positive for the virus, official figures show.
The NHS Test and Trace system has been hailed as a vital way for the country to manage the epidemic as it relaxes lockdown and social distancing measures. It involves asking people who have been in close contact with someone who has the virus to self-isolate.
The first statistics for the scheme, released today, show it was able to contact 5407 of 8117 people who tested positive between 28 May and 3 June, and was unable to contact the remaining 33 per cent. The people who did respond disclosed an average of around six close contacts, or 31,794 in total, and the contact tracers managed to reach around 85 per cent of this number.
An earlier contact tracing initiative that was running in the first weeks of the UK epidemic managed to reach 95 per cent of close contacts, before it was shut down. Sustaining a high percentage of contacts being reached will be crucial in the coming months, as modelling has shown levels above 80 per cent are needed to keep the spread of covid-19 in check.
The new figures didn’t include any data on the time between tests being ordered and tracers reaching the onward contacts of positive cases. It is important to keep this time period as short as possible to reduce the spread of the virus. Speaking at a press conference today, Dido Harding, who leads Test and Trace, said the scheme needs to work faster, though she didn’t provide a date for when these statistics would be released.
Asked by New Scientist why the service was reaching fewer contacts than its predecessor, Harding said it is because the system is still very new. “I don’t think that comparison looks too shabby for a service that’s a week old,” she said.
The vast majority of people the contact tracers spoke to have taken swift action to self-isolate. The figures show that 85 per cent isolated themselves within a day, with another 10 per cent doing so within 24 and 48 hours, 3 per cent between 48 and 72 hours, and 1 per cent taking longer.
Harding said a larger proportion of people were using the service online than expected, rather than by phone, and said there is “significant overcapacity” in both testing and tracing. It has now been around three weeks since the UK government last released figures on the number of people tested each day.