The UK has ordered a further 60m doses of the Pfizer/BioNTech Covid vaccine in an effort to ensure that booster jabs can be given from this autumn, the government has announced. The health secretary, Matt Hancock, made the announcement at a Downing Street press conference on Wednesday and said the extra doses would be used alongside other approved vaccines in “protecting the progress that we have made”. Hancock said: “We have a clear route out of this crisis but this is no time for complacency, it’s a time for caution – so we can keep the virus under control while we take steps back to normal life.” England’s deputy chief medical officer, Jonathan Van-Tam, said that cases had dropped to very low levels, on a par with the situation in September. On Wednesday 2,166 new coronavirus cases were reported in the UK and 29 deaths within 28 days of positive test. “My sense is that probably we are at, or close to, the bottom at the moment in terms of this level of disease in the UK,” he said. While Van-Tam said lockdown was the main reason behind the fall, he added that vaccines had helped in the later stages, especially in reducing the death rate in older people. “What is really important about these vaccines and about the vaccine rollout [is] that it really is the way out of getting into trouble of the same size and magnitude ever again,” he said. The UK has three Covid vaccines approved for use by the Medicines and Healthcare products Regulatory Agency: Pfizer/BioNTech, Oxford/AstraZeneca and Moderna, all of which require two doses for maximum protection. The MHRA is undertaking a rolling review to assess the Janssen and Novavax vaccines. Since the UK’s vaccination programme began on 8 December, a total of 33,959,908 people – about 64.5% of all adults – have received at least one dose of a Covid vaccine, and 13,581,076 people have had two jabs. The new announcement means the number of Pfizer doses ordered is the same as for the Oxford/AstraZeneca vaccine, with the UK expecting to receive 100m doses of each. The UK has bought 17m doses of the Moderna jab. Hancock said greater supplies of the Pfizer vaccine would help to safeguard the UK’s progress in tackling the coronavirus. “Our vaccination programme is bringing back our freedom, but the biggest risk to that progress is the risk posed by a new variant,” he said. “We’re working on our plans for booster shots, which are the best way to keep us safe and free while we get this disease under control across the whole world. These further 60m doses will be used, alongside others, as part of our booster programme from later this year, so we can protect the progress that we’ve all made.” The emergence of new coronavirus variants is of concern as some have shown signs of being able to at least partially evade the body’s immune responses, whether triggered by previous infection or certain Covid jabs. Such concerns have led scientists to call for the development of new formulations of Covid vaccines that are capable of offering better protection against such variants, and such work is already under way. The Department of Health and Social Care confirmed to the Guardian that the extra supply of Pfizer jabs would be of the same formulation as those currently offered – although Hancock emphasised the doses had not yet been manufactured. But boosters of current formulations could still be beneficial: the vaccines, including the Pfizer jab, still appear to offer some protection against new variants. A booster shot may also help to tackle the possibility of waning immunity among the most vulnerable people, who received their first Covid jabs months ago. Van-Tam added that a study would begin in June looking at whether the same or a different Covid jab to that given in previous vaccinations should be offered as a booster. He was asked at the Downing Street press briefing why the UK was not allowing adults who had received both jabs to meet up indoors, as in the US. Van-Tam said scientifically it would be “incredibly safe” for two fully vaccinated people to meet, but urged the public to wait a “teeny bit longer” for more normal social interactions to resume because of the importance of protecting younger, unvaccinated individuals. Dr Michael Head, senior research fellow in global health at the University of Southampton, also said that it was good to see the UK being proactive about booster doses. “We know the current vaccines are very effective at preventing infection and transmission, but the duration of immunity is unknown,” he said. However, Head said the global picture was of concern given many countries had barely begun their vaccine programmes. “India is currently an example of a country with an outbreak that is out of control. Across all the available vaccines, the UK has overall ordered far more doses than it actually needs,” he said. “New variants of concern will emerge, and these may have some level of impact upon the current vaccines. Therefore, it is important that any efforts are made to ensure surplus vaccines are made available for Covax and other lower-income countries. This will benefit both the UK and receiving countries.”