England’s test-and-trace system has been hit with fresh problems after there were delays in contacting nearly 2,000 people infected with coronavirus, and one in seven home tests failed to produce a result. An internet outage meant nearly 3,000 more people than usual were transferred to the contact-tracing system after testing positive for Covid-19 in the week ending 19 August. Two-thirds of these people had been tested days or weeks earlier, meaning there was a delay in reaching them and their close contacts when they should have been self-isolating. The Department of Health and Social Care said a “major internet outage” in the Southampton area was the cause of the problems but that it did not affect the delivery of test results and that people were transferred to the contact tracing system “as soon as this issue was resolved”. The proportion of home tests kits failing to produce a result that week rose sharply, from 4% to 15% of the total, equating to more than 18,000 tests. The DHSC figures also show that test and trace failed for a ninth week running to reach its target of contacting 80% of close contacts of people who test positive for Covid-19. Matt Hancock, the health secretary, acknowledged on Thursday that the programme was “not quite there” in reaching that target. He told LBC radio: “One of the challenges is we want to get NHS test and trace up to over 80% of contacts, getting them to self-isolate – we’re at just over 75%, so we’re nearly there but not quite there.” The outsourcing firms Serco and Sitel, who are paid about £200m between them to contact “non-complex” close contacts, only reached 62% of these people in the latest week. Delays in reaching these contacts are growing: one in four people were contacted by the outsourcing firms after 48 hours, the highest number in the three months since test and trace was launched. The number of people who tested positive for Covid-19 fell in the week to 19 August, for the first time since the start of July. This was despite a 2% increase in the number of tests carried out. It is too early to draw conclusions about whether this means community transmission of the virus is falling. As the number of tests has increased, so has the time taken for people to get their results. The proportion of test results received within 24 hours from Covid-19 testing centres dropped to just over 40% in the latest week, meaning most people were waiting longer than a day. Just over a third of tests taken at regional test sites produced results within 24 hours in the week to 19 August, down from 58% in the previous week. The Conservative peer Dido Harding, who is running test and trace and was appointed this month as interim executive chair of the new National Institute for Health Protection, said: “Every week we consistently reach the majority of people testing positive and their contacts, and [we] have now reached almost 300,000 people who may have unknowingly passed the virus on. “This country now has the capacity to test for coronavirus and trace contacts on an unprecedented scale to stop the spread of the virus. We will continue to build the service further to reach more and more people and to scale up our testing capacity by expanding our network of testing sites and investing in new technologies.” She added: “I urge everyone to use NHS test and trace to help everyone get back to a more normal way of life. If you have symptoms, book a test immediately, and if you are contacted by the service, follow the advice you receive.”