According to the first research study examining the COVID-19 vaccination of the entire UK population, between one-third and half of the population of the four British nations had not received the recommended number of COVID vaccinations and booster shots by the summer of 2022.
The results published today in The Lancet suggest that more than 7,000 hospital admissions and deaths could have been prevented by the summer of 2022 if the United Kingdom had better vaccination coverage.
Given the increasing number of COVID-19 cases and the recently identified new variant strain, this study provides timely insight into vaccine willingness and hesitancy, and could inform policymakers.
The research relied on secure access to anonymized health data for all individuals across all four nations of the United Kingdom, an advancement made possible only during the pandemic.
Co-author Angela Wood, Professor of Health Data Science at the Victor Phillip Dahdaleh Heart & Lung Research Institute, University of Cambridge and Deputy Director of the Data Science Centre, British Heart Foundation, said, „This is the first epidemiological study conducted at an individual level, using anonymized health data covering the entire UK population. We’ve created a detailed nationwide picture of who is under-vaccinated against COVID-19 and what risks under-vaccination poses.“
„These findings can be used to develop health policies and public health interventions to improve vaccine uptake. This approach could be extended to many other areas of medicine that offer great potential for new discoveries in understanding and treating diseases.“
Early introduction of the COVID-19 vaccine in the UK started strong, with over 90% of the population over 12 years old vaccinated with at least one dose by January 2022. However, the frequency of subsequent booster doses across the UK had not been fully understood.
Scientists from England, Scotland, Northern Ireland, and Wales – under the leadership of Health Data Research UK (HDR UK) and the University of Edinburgh – analyzed securely stored, routinely collected NHS data of individuals over five years between June 1 and September 30, 2022. All data was anonymized and only accessible to authorized researchers.
Subsequently, the data from all four nations was merged and harmonized, which was previously not possible. Individuals were grouped according to their vaccination status, with under-vaccination defined as not receiving all doses of a vaccine for which an individual was eligible.
The results show that the proportion of individuals who were under-vaccinated as of June 1, 2022, ranged from one-third to half of the population – 45.7% for England, 49.8% for Northern Ireland, 34.2% for Scotland, and 32.8% for Wales.
Mathematical modeling revealed that 7,180 hospital admissions and deaths out of approximately 40,400 severe COVID-19 cases during the four months of summer 2022 could have been prevented if the UK population had been fully vaccinated.
Under-vaccination was associated with significantly more hospital admissions and deaths across all age groups, with the likelihood of severe COVID-19 among under-vaccinated individuals over 75 being more than twice that of fully protected individuals.
The highest rates of under-vaccination were observed among younger individuals, males, individuals in more disadvantaged areas, and non-white ethnicities.
Researchers argue that the study, the largest ever conducted in the UK, also heralds a new era for British science by overcoming challenges in merging NHS data collected and stored differently across decentralized countries.
„The infrastructure is now in place to fully harness the potential of routinely collected NHS data in all four nations of the UK. We believe that we could and should extend these approaches to many other areas of medicine such as cancer, cardiovascular disease, and diabetes to seek a better understanding, prevention, and treatment of diseases.“
Professor Cathie Sudlow, Chief Scientist at Health Data Research UK and Director of the Data Science Center, British Heart Foundation (BHF).
Professor Sir Aziz Sheikh, Director of the Usher Institute at the University of Edinburgh, Research Director of HDR UK, and Co-Lead of the study, said, „Large-scale data studies have been crucial for pandemic response, allowing scientists to gain policy-relevant insights at speed. COVID-19 vaccines save lives. When new variants emerge, this study will help identify groups of our society and areas of the country where public health campaigns should be targeted and tailored.“
Das HDR UK COALESCE-Konsortium., (2024) Unterimpfung und schwere COVID-19-Ergebnisse: Metaanalyse nationaler Kohortenstudien in England, Nordirland, Schottland und Wales. Die Lanzette. doi.org/10.1016/S0140-6736(23)02467-4.