Between a third and a half of the UK population had not received the recommended number of COVID vaccinations and boosters by summer 2022, finds new research led by Health Data Research UK (HDR UK) and the University of Edinburgh. 

Published in The Lancet, the COALESCE study suggests that more than 7,000 hospitalisations and deaths might have been averted in summer 2022 if the UK had had better vaccine coverage. With COVID-19 cases on the rise and a new variant strain recently identified, this research provides a timely insight into vaccine uptake and hesitancy which could inform policy-makers.

Credit: Usher Institute, University of Edinburgh*

This study marks a significant milestone in HDR UK’s mission to unite the UK’s health data to enable discoveries that improve people’s lives and demonstrates the value and potential of population-wide health data studies.

Professor Cathie Sudlow, Chief Scientist at Health Data Research UK and Director of the British Heart Foundation (BHF) Data Science Centre, said:

“The infrastructure now exists to make full use of the potential of routinely collected data in the NHS across the four nations of the UK. We believe that we could and should extend these approaches to many other areas of medicine, such as cancer, heart disease and diabetes to search for better understanding, prevention and treatment of disease.”

Early COVID-19 vaccine rollout began strongly in the UK, with over 90% of the population over the age of 12 vaccinated with at least one dose by January 2022. However, rates of subsequent booster doses across the UK were not fully understood until now.

Credit: Usher Institute, University of Edinburgh*

Scientists from England, Scotland, Northern Ireland and Wales studied securely-held, routinely collected NHS data from everyone over 5 years of age during June 1 to September 30 2022. All data was de-identified and available only to approved researchers. 

Data from across the four countries was then pooled and harmonised – or made more uniform – a feat that was not possible until now. People were grouped by vaccine status, with under-vaccination defined as not having had all doses of a vaccine for which that a person was eligible.  

The findings reveal that the proportion of people who were under-vaccinated on June 1st 2022 ranged between one third and one half of the population – 45.7% for England, 49.8% for Northern Ireland, 34.2% for Scotland and 32.8% Wales.  

Mathematical modelling indicated that 7,180 hospitalisations and deaths out of around 40,400 severe COVID-19 outcomes during four months in summer 2022 might have been averted, if the UK population was fully vaccinated. 

Under-vaccination was related to significantly more hospitalisations and deaths across all age groups studied, with under-vaccinated people over 75 more than twice as likely to have a severe COVID-19 outcome than those who were fully protected. 

The highest rates of under-vaccination were found in younger people, men, people in areas of higher deprivation, and people of non-white ethnicity. 

Professor Sir Aziz Sheikh, Director of the Usher Institute at the University of Edinburgh, Co-Director of the HDR UK Inflammation and Immunity Research Driver Programme, and study co-lead, said:

“Large-scale data studies have been critical to pandemic management, allowing scientists to make policy-relevant findings at speed. COVID-19 vaccines save lives. As new variants emerge, this study will help to pinpoint groups of our society and areas of the country where public health campaigns should be focused and tailored for those communities.”

The HDR UK COALESCE study was set up to provide UK and devolved governments with data-driven insights into COVID-19 vaccination coverage and establish data pooling methods and infrastructure to pave the way for future UK-wide studies. Members of the public and patients were involved in the shaping of this work.

Alan Keys, a public contributor at the British Heart Foundation (BHF) Data Science Centre at HDR UK who sat on the steering group of the study and is a co-author on the paper, said:

“The research outcome is a powerful validation of the benefits of vaccination.”

The research relied on secure access to anonymised health data for the entire UK population across all four nations, which was only made possible by the ability to access and link datasets during the COVID-19 pandemic. Safe and secure research using whole population data could – and should – be extended to other diseases and help tackle some of the biggest health challenges, beyond COVID-19.

This work was supported by UK Research and Innovation through the National Core Studies: Data and Connectivity programme, with further support from HDR UK’s core funding and the British Heart Foundation, through work at the BHF Data Science Centre at HDR UK.

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*This image was created by the Usher Institute, The University of Edinburgh to accompany work done as part of the HDR UK COALESCE Consortium, led in partnership between the University of Edinburgh and Health Data Research UK. The study was supported by UK Research and Innovation National Core Studies: Data and Connectivity. © 2024 Usher Institute, The University of Edinburgh. All rights reserved.