Health 24 March 2021 The UK’s vaccine roll-out will slow down, but the hardest work has been done As long as a variant does not undo Britain's vaccine progress, we should still expect the country to unlock on time. Charles McQuillan - Pool / Getty Images Boris Johnson talks to people waiting to be vaccinated at the Lakeland Forum vaccination centre on 12 March 2021 in Enniskillen, Northern Ireland Sign UpGet the New Statesman\'s Morning Call email. Sign-up Last week (15-21 March) was easily the UK’s most successful yet for its vaccine programme. Across the country, 3.5 million people were given a first dose of the vaccine – that’s one million people every 48 hours. The UK also rolled out an average of nearly 100,000 second doses a day. This was a week to cherish, as the UK’s first dose vaccine roll-out will soon slow considerably. Vaccine delivery is unpredictable, but if we take Boris Johnson at his word (and I will leave you to decide if that is wise) and put aside for one moment the threat of the EU blocking supplies, then the Prime Minister has given us a decent idea of how much vaccine the UK will receive in the next five weeks or so. On 18 March Johnson said, in the manner of a verbal reasoning test, “we will receive slightly fewer vaccines in April than in March, but that is still more than we received in February”. While we don’t know how much vaccine the UK received in February, we do know that it administered 11.3 million doses during that time. To compare that to where we are now, just over two thirds of the way through March, a best guess would suggest the UK delivers around 14.5 million total doses this month. Next month we could, therefore, given the assumptions made, estimate that the UK delivers between 11.3 million and 14.5 million total doses. That seems like a high number – so why will the roll-out slow down? The issue is that the majority of those doses will be absorbed by the need to deliver second jabs to those who have already had the first. An under-reported fact of the vaccine roll-out is that the UK is delivering second doses more quickly than it needs to in theory. The UK has already delivered 2.3 million second doses. That is around the number of first doses that had been delivered by 11 January, ten weeks ago. In theory, the gap between doses can be up to, and should ideally be as long as, 12 weeks. If we assume the UK continues to roll out second doses on a ten-week timeline, that implies 1.8 million second doses this week (the final full week in March), and 2.5, 2.7, 3 and 3 million doses in the four weeks after that. This fits with what Matt Hancock said on 20 March: that around 12 million people will receive second doses in April. In other words, if the UK is unlikely to deliver more than 14.5 million total doses in April, as Johnson has implied, and we know 12 million will be accounted for by second doses, that leaves a maximum of just 2.5 million doses for any further first vaccinations in April. This matters, because the UK – despite its rapid roll-out this week – will likely fall short of offering all priority groups their first dose by Easter as once seemed possible. The government’s official target for these groups – which is everyone over 50 or classed as vulnerable – is slightly later: 15 April. Is this target going to be met? The UK had 4.6 million people left to vaccinate in these groups on 22 March, in just over three weeks. If we assume that the number of total doses delivered this week is as strong as last week, as the NHS has been advised, but also account for an expected surge in second doses from 0.7 million to 1.8 million, then we can expect a further 2.4 million first doses this week (although data released so far this week implies first doses this week may be as high as 2.8 million, based on a New Statesman estimate). That will leave 2.2 million “priority” people to vaccinate (or 1.8 million if 3 million are in fact reached this week.) Remember, the UK is projected to deliver a total of 2.5 million first doses in the whole of April, yet the government will likely need to vaccinate around 2.2 million people in just the first half of the month. There is a scenario, as shown in the graph above, where the government falls just short of its target. But by pushing second doses back slightly – which, as I say, appear to be being delivered more quickly than necessary – the target will be probably met; the government continues to say it will be. As April continues, however, the first dose roll-out is likely to be significantly slower. The heady speed at which the UK is currently expanding vaccine coverage will be replaced by a different form of success: full vaccination for the groups most at-risk. By the end of April, everyone over 70, as well as all front-line NHS staff and anyone extremely vulnerable, should have received their second doses. These are the most crucial 15 million people to vaccinate in full, as these groups have accounted for 88 per cent of Covid deaths thus far. That will make April a very effective month for the UK’s roll-out, even though expansion will likely almost entirely stop. By early May, therefore, the most at-risk groups in the UK should be fully vaccinated, and all other priority groups should have received their first dose. Together these groups have accounted for 99 per cent of those who have died from Covid so far. So is the UK’s plan to further unlock on 12 April, 17 May and 21 June in jeopardy? As long as the UK receives the doses the Prime Minister has announced, there is no reason to think that it is, despite the expected slowdown in first doses. Indeed, it is useful to remember that the UK once planned to vaccinate only the over-50s, health and care workers and those classed as vulnerable (this may be of little reassurance today to many people in their forties). As Kate Bingham, the then head of the UK’s vaccine task force, put it in October: “We just need to vaccinate everyone at risk.” That plan has changed, but the key fact is that the most important parts of the UK’s vaccine programme are being achieved. This would, of course, change if the vaccine supply were disrupted, and the recent furore over threats from the EU may yet jeopardise the forecasts offered above. But that is a separate question from whether the slowdown we can be certain is coming is cause for alarm. So long as a variant that undoes vaccine progress is not found in the UK, the data suggests that we should still expect the UK to unlock on time. › Joe Biden's $1.9trn Covid stimulus isn't transformative – yet Harry Lambert is special correspondent at the New Statesman and writes long reads. He tweets at @harrytlambert. Subscribe To stay on top of global affairs and enjoy even more international coverage subscribe for just £1 per month!