The government’s flagship test-and-trace system is failing to contact thousands of people in areas with the highest infection rates in England, raising further questions about the £10bn programme described by Boris Johnson as “world-beating”. Local leaders and directors of public health are demanding more control over the tracing operation amid concerns that their ability to contain the virus is being put at risk. Data obtained by the Guardian shows that in areas with the highest infection rates in England, the proportion of close contacts of infected people being reached is far below 80%, the level the government’s scientific advisers say is required for test and trace to be effective. In Luton, which has the sixth highest infection rate in England, only 47% of at-risk people were contacted by test and trace. In Leicester, which remains under a partial lockdown, the rate was 65%, meaning more than 3,300 people were not reached by the programme. Directors of public health have expressed frustration that local expertise has been sidelined under the centralised test-and-trace system, which has been handed to private firms such as Serco and Sitel. More than 5,500 people in four areas with the highest infection rates in England were not contacted when they should have been told to self-isolate, the Guardian has learned. These included 3,340 people in Leicester, 984 in Kirklees, 759 in Rochdale and 448 in Blackburn with Darwen. The government’s Scientific Advisory Group for Emergencies (Sage) has said that 80% of an infected person’s close contacts must be contacted and told to self-isolate within 48 to 72 hours for the national programme to be effective. In Blackburn with Darwen the figure was 54%; in Leicester 65%, in Rochdale 66% and in Kirklees 77%. Bradford council, which has the fourth-highest infection rate in England, declined to provide a figure but said “a high number of contacts” in the city were not traced by the national system. A council spokeswoman said it was asking the government “to allow us to set up a local extension to the national test-and-trace system which would enable us to follow up uncontacted data with door-to-door visits, something which no national system can really do.” Gerry Taylor, Luton borough council’s director of public health, said she was “very concerned” at the low rate in the Bedfordshire town. She said the centralised system was “too remote” to be able to reach all of its communities. “Clearly 47% is too low. The bulk of the contact tracing feels somewhat distant from us and working more closely together with the national system I think would be a huge advantage,” she said. Local leaders say they have the community links and relationships to hunt down the virus at street level, thereby plugging holes in the centralised system. Factors including language barriers, distrust of unknown callers and missed emails could explain the low contact completion rate in the worst-affected towns, where in some cases the virus is disproportionately affecting people of south Asian heritage. Under the current system, contact tracers attempt to reach close contacts of an infected person by text, email or up to 10 times by phone call. Kate Hollern, the Labour MP for Blackburn, said the national test-and-trace system had failed. “People are out there spreading the virus unknowingly due to this government failure. The responsibility and resources for this should have been with local government, who have the local knowledge. It’s a complete shambles and we really need to get control of it.” Lisa McNally, the director of public health at Sandwell Council in the West Midlands, which has the ninth highest infection rate in the country, said that last week only 40% of positive coronavirus cases in her area had been contacted by the national system. She said she asked the government for more data so those people could be traced locally but was told it was not possible. A Department of Health and Social Care spokesperson said: “NHS test and trace has already helped test and isolate more than 180,000 cases – helping us control the spread of the virus, prevent a second wave and save lives. This represents 81% of close contacts identified by those who test positive. “The service is working closely with local authorities across England to help manage local outbreaks. High quality data is critical to providing good public services and we’ve been providing increasingly detailed data to local directors of public health, helping them tackle local outbreaks and control this virus.”