Boris Johnson has labelled people opposed to vaccinations “nuts” as he urged the public to use an expanded flu jab programme to ease pressure on the NHS if there is a second wave of coronavirus this winter. Visiting a doctor’s surgery in east London to promote the extension of free flu jabs to more people, Johnson told staff: “There’s all these anti-vaxxers now. They are nuts, they are nuts.” The prime minister’s comments highlight the worries in government and among NHS leaders that a potential rise in Covid-19 infections in the coming months, coupled with a bad winter flu season, could overwhelm health services. In response, the usual winter programme of free flu vaccinations is being expanded this year to everyone over 50. Johnson said the plans would immunise “a very, very significant proportion of the population”, and urged people to take part. “We want everybody to get a flu jab in the run-up to this winter,” he told Sky News at the surgery. “And that’s why we’re rolling out the biggest ever programme of flu immunisation. “We’re aiming first of all for school children up to year seven, for pregnant women, for people over 65, people who have been shielded. But then we’ll be extending it to people from 50 to 65. “The reason for doing this is to protect the NHS in the winter months because, obviously, we’ve still got Covid – we’ve still got the threat of a second spike of Covid, and it’s vital therefore to keep that pressure off the NHS by everybody getting a flu jab, and I really hope everybody will.” The government has so far shied away from the idea of making any vaccinations compulsory, despite a fall in childhood inoculation levels, something partly put down to social media misinformation and scare stories about vaccines. Last year, the UK health secretary, Matt Hancock, said the government was “looking very seriously” at making vaccinations compulsory for state school pupils and had taken advice on how such a law could work, but the idea was played down by No 10. Johnson said that while he was worried about a second wave of Covid-19, he believed the UK would be over the crisis by mid-2021. “Whether it came from … a bat, a pangolin or however it emerged, it was a very, very nasty thing for the human race,” he said. “And I think by the middle of next year we will be well on the way past it.” He added: “But, I must be clear with people, I do still think that we have tough times ahead in keeping this virus under control.” Asked how long he thought distancing and other protective measures would be needed, Johnson said: “The use of face masks, the use of all the social distancing measures really does depend on our ability collectively to get the pandemic right down and to keep it down. “I’m not going to make a prediction about when these various social distancing measures will come off. Obviously we have been able to reduce some of them. We no longer ask people to stay at home, we’re trying to get back much closer to normal, but our ability to dispense with the social distancing measures will depend on our continued ability to drive down the virus.” On the day masks became compulsory for almost all adults in England in shops, banks and takeaway food shops, Johnson was asked if the public should be “shaming” those not wearing them. He said: “I think we should rely on the massive common sense of the British people that have so far delivered the results that we’ve seen, and that’s going to work.”