Data is due in the coming weeks on whether mixing Covid-19 vaccines could offer the template for an autumn booster vaccine campaign, the Health Secretary has said.

Matt Hancock said that while second doses of the current vaccines offered very strong protection, “there is more protection still that we think that you can get from a booster jab”.

He said there was a need to “get the logistics right” for any future vaccine campaign after GPs and NHS leaders expressed concern about how it would be staffed.

Seven vaccines are currently being tested in the Cov-Boost trial to see which could be used in any forthcoming autumn vaccination programme.

Experts believe that all seven vaccines will boost immunity, and lab studies are checking their response to variants circulating in the UK, including those first identified in India, Kent and South Africa.

The £19.3 million UK clinical trial is testing the Pfizer jab alongside those from AstraZeneca, Moderna, Novavax, Janssen from Johnson & Johnson, Valneva and CureVac.

The study will examine key questions such as whether people who have had two doses of AstraZeneca may get more benefit from a third dose of Pfizer.

“When we know the results of that (trial), then we will set out the full plans for the booster programme over the autumn,” Mr Hancock told BBC Breakfast on Monday.

“We’ve got to make sure we get the logistics right; for instance, GPs have been so heavily involved in this vaccination effort, but GPs have also got to do their day job, so that’s something we’re working hard on now and, in the next few weeks, when we get the clinical data through on what’s the most effective combinations to have… then we’ll set out all the details of the booster programme for the autumn.”

Last week, Professor Sir Andrew Pollard, head of the Oxford Vaccine Group, told MPs “we have absolutely no evidence that there is a need for a third dose” at the moment.

He said the UK was seeing “very high levels of protection against hospitalisation with two doses” using current vaccines and it was too early to say when protection would wane.

Professor Martin Marshall, chair of Royal College of GPs, told BBC Radio 4’s Today programme on Monday that any booster programme needed to be properly resourced.

He said: “I do believe that general practice has a very important role to play because we were part of the successes of the current programme because general practice knows how to do it.

“But it needs to be adequately resourced to allow us to do it well.

“We can’t have GPs and practice nurses and pharmacists diverted away from normal business, because we can’t afford to let our patients down on all the many other things that we do in general practice.”

He suggested booster campaigns might be conducted by non-clinical, trained staff to free up time for doctors and nurses.

“We do need to (look) into what the programme looks like for an endemic condition, when we’re outside the crisis mode that we’ve been in the last six months,” he said.

“We do need to know, first of all, whether a booster vaccination programme is needed. Who will need it? We need to know where it will be given and by whom.

“In general practice, for example, where three-quarters of the vaccines have been given, our GPs and nurses are exceptionally busy. Is it possible that a booster campaign can be given by non-clinical trained vaccination staff?”

He added that general practices administer large flu campaigns in the winter and asked whether it would be possible to give a Covid-19 jab at the same time as “clearly that would be a very efficient process”.

Chris Hopson, chief executive of NHS Providers, said the health service needs time to plan for potential Covid-19 vaccine booster campaigns to make them “business as usual” instead of “emergency response”.

He told Times Radio: “Flu jabs start in September, so if we’re going to do one jab in one arm, one jab in the other, we really do need to know quite quickly.”

He said Covid-19 vaccines were “probably” going to be needed on “an annual basis for, I don’t know, at least five, six, seven, eight, nine, 10 years.”

Meanwhile, Professor Anthony Harnden, deputy chairman of the Joint Committee on Vaccination and Immunisation, said decisions about future Covid-19 vaccine booster campaigns would be data-driven but would consider the need for planning within the NHS.

He told BBC Radio 4’s Today programme: “One of the key things is that these vaccines have been incredibly successful and I think that if we can get two doses into the majority of the adult population, then we’ll be in a really good place, but we may not be so with flu, and flu is going to be really important this winter to get vaccinated against.

“In terms of any booster campaign, we need to think about who this will target.

“Those that received the vaccine furthest away – when we started in December last year and January – were the very elderly and vulnerable, and, of course, it will be many months since they’d have their vaccine, so we do need to think about whether we need to boost those particular age groups.”

Prof Harnden said he thought flu could be a “bigger problem” than Covid-19 this winter.

He added: “I will emphasise that actually flu could be potentially a bigger problem this winter than Covid-19.

“We’ve had a very, very low prevalence of flu for the last few years, particularly virtually nil during lockdown, and we do know that when flu has been circulating in very low numbers immunity drops in the population, and it comes back to bite us. So, flu can be really, really important this winter.”

Elsewhere, Calum Semple, a member of the Scientific Advisory Group for Emergencies (Sage) and professor of child health and outbreak medicine at the University of Liverpool, told Sky News “it’s a really close call” on whether children should be vaccinated, given their low risk of serious illness from Covid-19.

He added: “The knowledge around safety in children is growing, but I would say it’s not as robust as it needs to be if there was to be blanket vaccination of children who themselves are not at risk of very severe disease.

“That’s the crux of the matter. If you are going to vaccinate children to protect society, that is a fair decision that can be made, but you want to do that with full knowledge of the safety data.”