Appearing in front of the Commons Science and Technology Committee, Professor Gilbert also warned that easing Covid restrictions too quickly could result in higher transmission and increase the risk of new variants emerging with more resistance to existing vaccines.
The University of Oxford professor’s comments come just weeks after the former head of the UK’s vaccine taskforce, Kate Bingham, suggested there needs to be a more efficient way of administering vaccines, including the use of pills and patches.
Professor Gilbert told MPs that “we are also thinking about second-generation formulations of vaccines” which could replace injections, but warned they would “take time to develop”.
“We have flu vaccines that are given by nasal spray – and this could be a very good approach in the future to use vaccines against coronaviruses,” she told MPs on Wednesday.
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“It is also possible to consider oral vaccination where you have to take a tablet that will give the immunisation, and that would have a lot of benefits for vaccine rollout – if you didn’t need to use the needles and syringes for people.”
Professor Gilbert added: “Both of those are approaches which we are beginning to assess. They will take time to develop.
“They will have to be tested for safety and then for efficacy as well because the immune responses that will be generated by both of those approaches will be a little bit different to what we get from an intramuscular injection.”
Speaking last month, Ms Bingham, who was tasked with procuring vaccines on behalf of the UK government last year, said that two injections delivered by health care professionals was “not a good way of delivering vaccines”.
In an interview with the BBC, the former vaccine taskforce chief insisted: “We need to get vaccine formats which are much more scalable and distributable, so whether they are pills or patches or nose sprays.”
Ms Bingham said the UK needed to be working together with international partners to “develop those tweaked vaccines that will address new variants, which will inevitably arise because that’s what viruses do they mutate, and we need to improve the vaccine format.”
Addressing the easing of restrictions, professor Gilbert also told the committee that in order to ensure the UK has the “lowest chance” of new variants emerging “we need to prevent the virus from transmitting between people” – something she said the vaccine was already doing effectively.
“We cannot allow only the vaccines to do all the work of protecting the population, while at the current time in the UK we still have relatively high levels of transmission,” she told MPs.
“And there is a danger that if measures are lifted too quickly that transmission could increase, and that puts us at a greater risk of selection of new variants that are not so well effectively neutralised by the virus.”
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