Men, obese people, high-risk workers and ethnic minorities should be targeted in the next phase of the vaccine rollout, government scientific advisors said on Tuesday.
The Joint Committee on Vaccination and Immunisation (JCVI) has told the NHS to proactively encourage take-up of the jab in these groups, due to their heightened risk from Covid.
Despite the increased danger, the committee confirmed it would not prioritise individual groups, but rather continue with an age-based rollout, with people aged 45 to 49 now being invited to come forward.
They said this simple approach would ensure the overall speed of distribution is maintained, meaning jabs should reach vulnerable people more rapidly anyway.
“JCVI strongly advises that individuals in these groups promptly take up the offer of vaccination when they are offered, and that deployment teams should utilise their understanding of local health systems and demographics, combined with clear communications and outreach activity, to promote vaccination in these groups,” the guidance says.
“Unvaccinated individuals who are at increased risk of severe outcomes from Covid-19 on account of their occupation, male sex, obesity or ethnic background are likely to be vaccinated most rapidly by an operationally simple vaccine strategy.”
Research collated by the committee suggests that warehouse workers, construction and manufacturing employees, and those in “contact” industries such as hairdressing are the workers most at risk.
The NHS vaccine website crashed on Tuesday morning as people in their late forties began to book appointments.
Meanwhile the first doses of the Moderna vaccine - the third to achieve regulatory approval in the UK - were administered in England.
Matt Hancock told the House of Commons that England was on track to vaccinate all adults by the end of July, and Nadhim Zahawi, the rollout minister, assured Muslims that it was permissible to take the vaccine during Ramadan.
It came as Oxford University announced a new trial to assess the effect of mixing vaccines, as experts warned shortages may prevent people getting a third “booster” jab from the same manufacturer as they obtained the first two.
The existing Com-Cov study, which is investigating alternating doses of the Oxford-AstraZeneca and Prizer vaccines, is extending to include the Moderna and Novavax jabs as well.
Professor Jeremy Brown, a JCVI committee member, said: “It’s practically going to have to be that way, because once you’ve completed a course of say the Moderna or Pfizer or AstraZeneca with two doses, in the future it’s going to be quite difficult to guarantee that you get the same type of vaccine again.”
A further 1,050 over-50s will join the study, which will examine blood samples to assess immune response.
Professor Matthew Snape, who is leading the research, said mixing vaccine types could yield a better immune response than using a single type, adding that he would be “surprised” if doing so produced a suboptimal response.
“We don’t know, and that’s why it’s important to do the study,” he said.
"If we can show that these mixed schedules generate an immune response that is as good as the standard schedules, and without a significant increase in the vaccine reactions, this will potentially allow more people to complete their Covid-19 immunisation course more rapidly.
"This would also create resilience within the system in the event of a shortfall in availability of any of the vaccines in use."