Boris Johnson has announced plans for people across the UK to be able to spend Christmas with their extended families, while conceding that the government’s test-and-trace system “hasn’t had as much impact as we would have wanted” in reducing the spread of coronavirus. The prime minister used a Downing Street press conference alongside Sir Simon Stevens, the chief executive of NHS England, to try to push the message that people should abide by the four-week lockdown in England. Johnson and Stevens noted that 11,000-plus people were in hospital with coronavirus, and said that without public compliance over the lockdown, the NHS could struggle badly. “This second wave of coronavirus is real and it’s serious,” Stevens said, comparing the current number of Covid patients with the 3,000 that would be seen during a bad winter flu season. “This is not speculation, this is fact,” he said, a reference to scepticism among some Conservative MPs and others about projections of the potential impact of a new surge in Covid without the lockdown. Official figures released on Thursday showed that another 378 people had died within 28 days of testing positive for Covid-19, bringing the UK total to 48,120. There were also a further 24,141 lab-confirmed cases, bringing the UK total to 1,123,197. Separate figures for deaths where the virus has been mentioned on the death certificate show there have now been around 63,000 deaths involving Covid-19 in the UK. The UK Statistics Authority criticised ministers earlier in the day for the use of data and predictions during pre-lockdown briefings at the weekend, saying there needed to be more transparency about how they were used. Stevens showed only one chart at Thursday’s press conference, which plotted actual hospital admissions caused by Covid over recent months. “Sometimes the charts can be a bit hard to keep up with,” he said. Johnson said the government and the administrations in Scotland, Wales and Northern Ireland were “working together on a joint approach to the Christmas period, because all of us want to ensure families can come together wherever they live”. “I know many of you are anxious, weary and quite frankly fed up with the very mention of this virus,” he said. “But I want to assure you this is not a repeat of the spring. Schools, universities and nurseries are all staying open. And these measures, though they are tough, are time-limited. “The advice I have received suggests that four weeks is enough for these measures to make a real impact. So these rules will expire, and on 2 December we plan to move back to a tiered approach. There is light at the end of the tunnel.” Johnson set out what he said were the three strands to being able to “put the coronavirus back in its box”: better treatments for the illness, testing and the prospect of a vaccine. Questioned about figures showing that only 59.9% of close contacts of people who test positive for coronavirus are being reached and asked to self-isolate, Johnson said he accepted that the test-and-trace system could be better. “It has come in for a lot of criticism, and clearly it has taken too long for people to get their results sometimes. But they are improving,” he said. “It hasn’t had as much impact as we would have wanted. But there’s no doubt that by identifying people who have the disease, and identifying the localities where people have the disease, being able to get the R down in a way I don’t think we would have otherwise done, it’s had an effect.” Highlighting plans to roll out mass, near-instant tests, with a pilot under way in Liverpool, Johnson said he hoped that such technology would “offer a real way forward through this crisis”. Asked about vaccines, Johnson and Stevens expressed optimism that at least one of the many in development would prove effective, with the PM likening this to the “number of shots raining down on the goal”. Stevens declined to criticise the timing of the new lockdown. Government scientists had first advised a “circuit breaker” shutdown to stem infection rates in September. He said the NHS had spent the summer catching up with cancelled routine operations. “When the facts change you’ve got to act in accordance with those new facts, and quickly,” Stevens said.