Vaccination has been linked to a substantial reduction in the risk of Covid-19 admissions to Scotland’s hospitals, landmark research suggests.
The study is the first to describe across an entire country the effect of the Pfizer and Oxford-AstraZeneca jabs in the community on preventing severe illness resulting in hospitalisation.
Previous results about vaccine efficacy have come from clinical trials.
Hospitalisation drop
By the fourth week after receiving the initial dose, the Pfizer and Oxford-AstraZeneca vaccines were shown to reduce the risk of hospitalisation from Covid-19 by up to 85 per cent and 94 per cent, respectively.
Among those aged 80 years and over - one of the highest risk groups - vaccination was associated with an 81 per cent reduction in hospitalisation risk in the fourth week, when the results for both vaccines were combined.
Entire population
As part of the EAVE II project, which uses patient data to track the pandemic and the vaccine roll out in real time, researchers from the Universities of Edinburgh, Strathclyde, Aberdeen, Glasgow and St Andrew’s and Public Health Scotland (PHS) analysed a dataset covering the entire Scottish population of 5.4 million.
Data on vaccine effect was gathered between 8 December and 15 February.
During this period, 1.14 million vaccines were administered and 21 per cent of the Scottish population had received a first dose based on Scottish Government prioritisation.
First jab
The Pfizer vaccine has been received by some 650,000 people and 490,000 have had the Oxford-AstraZeneca vaccine.
Researchers analysed data for every week during this period – including GP records on vaccination, hospital admissions, death registrations and laboratory test results – and compared the outcomes of those who had received their first jab with those who had not.
The preliminary results have been posted on the SSRN preprint server and submitted to a journal to undergo peer review.
The study team says the findings are applicable to other countries that are using the Pfizer and Oxford-AstraZeneca vaccines. They caution that the data does not allow for comparisons between the two.
The work was funded by the Medical Research Council, the National Institute for Health Research and Health Data Research UK, and supported by the Scottish Government.
Additional support has been provided through Public Health Scotland and Scottish Government Director-General Health and Social Care, and the UKRI COVID-19 National Core Studies Data and Connectivity programme led by HDR UK.