Here are the main points from the news conference. Boris Johnson was joined by Prof Chris Whitty, the government’s chief medical adviser, and Sir Patrick Vallance, the government’s chief scientific adviser. Johnson said that Britain was facing the “worst public health crisis for a generation” and that “many more” people would die. (See 5.52pm.) In a marked change of tone from his previous press conferences and interviews on this subject, he explained that Britons were going to face considerable disruption to ordinary life over the next few months as the government introduced measures to delay and limit the spread of Covid-19. Johnson said the true number of coronavirus cases in the population was probably “much higher” than official figures suggest. He said: The number of cases will rise sharply, indeed the true number of cases is higher - perhaps much higher - than the number of cases we have so far confirmed with tests. Vallance said he thought the actual number of people infected in the UK at the moment could be between 5,000 and 10,000. The official number of confirmed cases is 596. Johnson confirmed that the UK was now moving out of the “contain” phase and into the “delay” phase for dealing with the epidemic. He said: This is now not just to attempt to contain the disease as far as possible, but to delay its spread and thereby minimise the suffering. If we delay the peak even by a few weeks, then our NHS will be in a stronger state as the weather improves and fewer people suffer from normal respiratory diseases, more beds are available and we’ll have more time for medical research. We can also act to stretch the peak of the disease over a longer period so that our society is better able to cope. Johnson said that people with a fever or a new, persistent cough were now being asked to stay at home for seven days. He also said schools were being advised to cancel overseas trips, and the over-70s and the ill were being told to avoid cruises. He said: From tomorrow, if you have coronavirus symptoms, however mild -- either a new continuous cough or a high temperature -- then you should stay at home for at least 7 days to protect others and help slow the spread of the disease. We advise all those over 70 and those with serious medical conditions against going on cruises and we advise against international school trips. He said that at some point in the future the government would go further, and ask all family members to stay at home if someone was ill. He said: At some point in the next few weeks we are likely to go further and if someone in a household has those symptoms then we will be asking everyone in that household will stay at home. He also said that at some point in the future the elderly would be asked to stay away from places or people to avoid infection. He did not give details. He said at the moment he was not planning to ban sporting events, but he said this was being kept under review. He said: We are considering the question of banning major public events such as sporting fixtures. And the scientific advice, as we’ve said over the last couple of weeks, is that banning such events will have little effect on the spread but there’s also the issue of the burden that such events can place on public services. In a mild dig at Nicola Sturgeon, the Scottish first minister who is planning to cancel events with crowds of more than 500 people from next week and whose decision to announce the results of the Cobra meeting before Johnson angered some in No 10, Johnson said that Scotland might have a particular issue with the resilience of its emergency services. He implied that that was why the Scots needed a different policy. Vallance said cancelling sporting events could be counterproductive. He explained: On average, one person infects two or three others. You therefore have a very low probability of infecting a large number of people in a stadium and a rather higher probability of infecting people very close to you. And that means that most of the transmission actually tends to take place with friends and colleagues and those in close environments - and not in the big environments. Though it is true that any cancellation of things can have some effect, if you then get a displacement activity where you end up with everyone congregating somewhere else, you may actually perversely have an increased risk, particularly in an indoor environment. So it doesn’t mean you shouldn’t at some point make the decision from a resilience point but this is not a major way to tackle this epidemic. Johnson defended his decision not to introduce measures as draconian as those being introduced in some other other countries. He said: The measures that I have discussed today... staying at home if you think you have the symptoms, your whole household staying at home, looking after the elderly - making sure the elderly and vulnerable stay at home - these are the three most powerful defensive lines. We think it’s very important to maintain public trust and confidence in what we are doing, throughout this challenging time, always to be guided by the best possible scientific advice. He and his advisers also argued that, if self-isolation measures were introduced too early, they would be ineffective - because people would ignore them at the point where they were most necessary. Whitty said he thought the overall mortality rate from Covid-19 was around 1% or less. It was higher for older people, and people in the vulnerable group, and lower for others, he said. But he said he did not want to speculate on who many people might die from the illness because he said the scientists just did not know how many people are infected. He said, although an 80% infection rate was the government’s top reasonable worst case scenario, nowhere in the world was currently coming close to an infection level like that. Vallance said that the outbreak in the UK could be about four weeks behind the outbreak in Italy. Vallance said the peak of the epidemic in the UK was “something like 10 to 14 weeks away”. That’s all from me for today. Thanks for the comments.