Rushing the booster jab roll out risks doing more harm than good, members of the Joint Committee on Vaccine and Immunisation (JCVI) have warned.
Last week Jeremy Hunt, the former Health Secretary, called for booster shots to be given five months after the second dose to increase uptake, rather than waiting for the six months recommended by the JCVI.
Ministers are considering moving the deadline and allowing all over-50s to book their boosters after five months, so they do not have to wait several weeks for an appointment after reaching the six month mark.
But members of the JCVI last night warned that it would be better to focus on increasing booster uptake in the older age groups, while encouraging those who have not had their first two doses to get vaccinated.
Latest figures from the UK Health Security Agency show that four in ten people admitted to hospital with Covid-19 are not fully-vaccinated, with under-30s four times more likely to be admitted than if they’ve not had a jab.
Professor Adam Finn said the value of the booster programme is ‘questionable’ the further it moves down the eligible groups to younger people, and urged the government to ‘stick to the science.’
“Just giving more people vaccines, including people who maybe don't actually need the vaccines yet, could actually run the risk of making things worse rather than better,” he told Trevor Phillips On Sunday on Sky News.
"If you boost people before they actually need the vaccine, it is in some senses a waste of vaccine, but also it means that you are immunising them earlier and they may make a smaller response to the vaccine and that response may wear off earlier.
"I think we do need to focus particularly on the most elderly people. So I think the idea of just getting more doses indiscriminately into people's arms is not really necessarily going to solve the problem.”
Speaking to The Telegraph, Prof Finn also cautioned against cutting the gap between second doses and boosters down from six months would be advisable to speed up the rollout he said: "Personally I think that is a really ill-conceived idea.
"That's like trying to say the way we can get our numbers up and meet our targets to make everyone happy by immunising the wrong people."
JCVI member Anthony Harnden also argued that immunity wanes slowed in younger people, so boosting too early may do little good in helping long term protection.
“The priority are the groups that had their second vaccine six months or more ago, which includes elderly and vulnerable,” he said.
“And as the programme is designed to reduce hospitalisation and deaths it makes sense to focus on these risk groups.
“Earlier vaccination runs the risk of reducing the peak protection attained after the boost which may in turn reduce the duration of protection. And we know from other vaccines that immunity wanes slower the younger you are.”
More than five million people have had a booster jab in England, and the NHS today confirmed that an extra two million people who are eligible for a booster will receive an invitation that week.
Sajid Javid the Health Secretary last week confirmed that people who do not get an invite within a week of reaching the six month mark can book a jab without the official notification.
The NHS estimates there around 10 million people in England are eligible for a booster, including health and care workers, those with underlying health conditions, and people aged 50 and over.
Nearly 60 per cent of over-80s have now had their booster and 46 per cent of the 75 to 79s. However, fewer than one third of the 70 to 74s have had a third jab, and just 12 per cent of the 65 to 69s.
However the Covid-19 Actuaries Response Group said that the gap between people becoming eligible and getting their booster was growing, with around 5.5 million now waiting.
The Government has repeatedly warned that high uptake of boosters is vital for avoiding Plan B this winter, and the NHS today urged people to come forward.
NHS medical director Professor Stephen Powis said: “Winter is coming and infection rates are rising and so it's now really important that everyone receiving their invite for a booster vaccine from the NHS this week books in at one of the convenient vaccinations sites around the country offering this crucial, additional protection.
“Thanks to NHS staff, nine in 10 people have had a first dose, saving tens of thousands of lives, and now more than five million boosters have been delivered in the first month of the rollout.
“I would urge anyone receiving an invite this week to book in as soon as possible - the booster dose is proven to significantly increase protection against Covid and will provide vital protection this winter.”