字幕表 動画を再生する 英語字幕をプリント Britain is not alone in the fight against Covid-19, but it is an interesting case study for those looking to escape lockdown. On the one hand, one of the most advanced vaccine programmes in the world. On the other, a new variant of coronavirus that's infecting the population in record numbers. Hopes now lie with the UK government's pledge to offer a vaccine to 15m of the most vulnerable Britons by the middle of February. 88 per cent of people currently dying from the virus come from these groups. With them protected it's thought that the rest of the population should be able to enjoy more freedom without putting the health services under too much strain. That moment may come after the February half-term, although we should remain extremely cautious about the timetable ahead. But whether the vaccination target will be met and whether it will be enough to end lockdown are two very different questions. And a lot could happen between now and mid-February that would change the outcome of both. Here's what to look out for. If the UK wants to vaccinate 15m people by mid-February it will have to administer 2.5m doses per week for the next five weeks. At the moment, that figure is closer to 2.1m per week. And Britain's health secretary has suggested delays in scaling that up are down to the limited supply of vaccines. The rate limiting step is the supply of vaccine. And we're working with the companies to increase the supply. It's true that manufacturing is still getting up to speed. And there are even shortages of the glass vials that batches are transported in. But bringing enough vaccination sites on stream and hiring enough people to man them is also presenting challenges. The government has set up plans for 2,700 vaccination centres, including hospitals, doctor surgeries, pharmacies, and up to 15 mass vaccination sites. At the same time the NHS has hired 80,000 professionals to run the campaign. But frustrations have mounted about how quickly the programme is being set up, and policymakers are already looking at other ways to accelerate uptake. Right now, Israel is head and shoulders above other countries when it comes to vaccinations per capita, thanks in part to a highly centralised, digital health system that makes it easy to reach out to members of the public and sign them up for a jab. Britain has started to follow this lead by sending out vaccination letters from central government. And in another attempt to speed things along, Westminster has extended the gap between first and second doses, although that strategy has its critics. When Pfizer and BioNTech and Oxford AstraZeneca completed their clinical trials they recommended a three-week gap between first and second doses. But now a growing number of scientists, including the UK'S Joint Committee on Vaccination and Immunisation and researchers at Oxford and AstraZeneca, are recommending that the gap gets pushed much further out to up to 12 weeks. By extending the gap, we are going to, over the next three months be able to essentially double the number of people who can be vaccinated. Hospitalisations and deaths from Covid-19 are currently at the highest they've ever been. With more people receiving the limited protection offered by the first dose quicker, the logic is this strategy could take pressure off Britain's overstretched health service. And that, in turn, could offer a quicker path to easing restrictions. Even though some scientists are confident that extending the gap between doses won't make the vaccine any less effective, others aren't sure there's enough evidence about how much immunity a single dose confers. They've also warned that partially boosting the immune system could create an opportunity for the virus to mutate and become more resistant. If that happens, all hopes of a swift exit from the crisis will be dashed. Thankfully, at the moment, there isn't evidence that this is likely to happen. The current UK lockdown is in large part due to a new variant that emerged in London and Kent called B117. Early research suggests that neither this variant, nor one originating in South Africa, are likely to be more resistant to the current crop of vaccines. But experts have warned that we should be prepared for many more variants to emerge this year than last as the virus adapts to its new human host. If new variants evade both natural and vaccine-induced immune responses the vaccines can be tweaked to catch up. But analysts say this could take anywhere between one and nine months, depending on what regulators demand. The race between vaccines and the virus has a long way to go. But the new variants that popped up last year have given Covid-19 a head start. Whether the UK hits its vaccination target of 15m people by mid-February is hugely important but not just for the sake of easing the lockdown here. If vaccines don't catch up with the virus soon, we could all find ourselves back on square one with a new variant pulling far ahead.