The statistics and arguments behind vaccine roll out priorities

Two analyses of the numbers and arguments behind the prioritisation for vaccine roll out. The second puts these in the context of the pressures to include a wider range of “key workers”.

Behind the numbers: how the recipients of the Covid vaccine are prioritised 

David Spiegelhalter and Anthony Masters 

The Joint Committee on Vaccination and Immunisation (JCVI) makes recommendations about priorities for vaccination rollout and its primary aim in the first phase has been to minimise death and severe illness from Covid-19. Its analysis found that this was best achieved by protecting the vulnerable rather than reducing the spread of the virus, particularly as it remains uncertain how much current vaccines prevent transmission.

The question then becomes statistical: who is most at risk of catching and then dying from Covid? Two major independent studies, QCovid and OpenSafely, have analysed millions of general practice records and concluded that someone’s age is the key risk factor, with the risk of death from Covid roughly doubling for each six-seven years of additional age. For registrations in England and Wales to 15 January, 74% of Covid deaths were in people aged 75 and over. Even if the aim were to save the most years of life, JCVI found that it would be best to focus on the elderly first: older people’s increased risk is sufficient to dominate their shorter life expectancy.

The JCVI has defined nine priority groups down to people aged 50, which together comprise 99% of Covid deaths. These start with vaccinating older ages and those with serious health conditions, such as kidney disease, who had been advised to shield. People who provide health and social care are both at extra risk themselves and key in transmission and have been put among urgent groups. Although male sex, ethnicity and deprivation are independent risk factors even after allowing for age and medical conditions, OpenSafely found that each at most doubles the risk, so age is still the dominant factor in the prioritisation.

The UK’s vaccine development, procurement and rollout have been extremely effective. YouGov surveys estimate about 80% of UK adults are willing to get a Covid-19 vaccine, but early data shows some groups are more reluctant: take-up in black people over 80 may be around half that of white people over 80. It is unknown whether targeted campaigns can counter such hesitancy.

• David Spiegelhalter is chair of the Winton Centre for Risk and Evidence Communication at Cambridge. Anthony Masters is statistical ambassador for the Royal Statistical Society

Older age groups in UK ‘will die’ if Covid vaccine priority goes to younger key workers

Michael Savage

Prioritising vaccinations for key workers such as teachers and police over the next few weeks would inevitably lead to more deaths among older people, government vaccination advisers have warned.

There have been various demands for certain groups to be given greater priority in the vaccine programme. Labour has called for key workers such as teachers and police to be vaccinated alongside older groups when extra capacity becomes available and after the over 70s have received a jab, while some doctors have called for healthcare workers to be given their second dose sooner than planned.

However, figures from the expert committee warned that lives would be lost unnecessarily if current plans to prioritise people by age and underlying health conditions were altered.

Adam Finn, a professor of paediatrics who sits on the Joint Committee on Vaccination and Immunisation (JCVI), which advises ministers on vaccine distribution, said it would be “politically, socially and ethically unacceptable” to prioritise younger groups over older ones at greater risk.

“We worked out that if you give 20 people in a care home a dose of vaccine, you’ll save a life,” he said. “If you give 160 people in their 80s a dose of vaccine, you’ll save a life. But once you get down to people in their 60s, you’re up to more than 1,000. If you go down to teachers or policemen, you’re approaching one in 50,000. It’s an extraordinarily inefficient way in the crisis to use vaccines – to start going out to these other lobbying groups who are perceiving themselves to be at enhanced risk of exposure, but who are not actually and demonstrably at enhanced risk of getting sick and dying.

“If in the next month you immunised 200,000 teachers, there will be 200,000 people in their 70s who won’t get that vaccine. You’ll save a few teachers’ lives, and you’ll waste the lives of a lot of people in their 70s. It is politically, socially and ethically unacceptable that we turn our back on older people and say, ‘It’s too bad, just stay home and die.’”

He said that there will come a time when ministers may want to switch away from the JCVI’s focus on hospitalisation and deaths, and target certain key workers in the next phase of the vaccine programme.

All those aged 50 and over have been placed in groups 1 to 9 of the first phase of the distribution effort, as well as those most vulnerable to the disease. Maggie Wearmouth, another member of the JCVI, said: “Our duty is to protect the most vulnerable members of society as quickly and efficiently as possible. Every time you vaccinate one person, you are denying that opportunity to someone else. The vaccine rollout for priority groups 1-4 is going really well at the moment. Proceeding swiftly with groups 5-9 is the best way to ensure the protection of most of the groups asking for priority consideration.”

The latest Opinium poll for the Observer found that almost 94% of the public think there must be some workers that qualify for vaccine priority, either alongside or above some older age groups. More than half (54%) backed prioritisation for teachers, and a similar proportion (53%) backed the move for police.