Covid-19 vaccination rollout has been linked to a substantial fall in the risk of admission to hospitals from the disease in Scotland, according to early data from a study on the effect of the Pfizer and Oxford-AstraZeneca shots in the community.
Researchers compared hospital admissions among those who have had their first dose and those who have not.
By the fourth week after receiving the initial dose, the Pfizer vaccine reduced the risk of hospital admission from Covid-19 by up to 85%. The Oxford-AstraZeneca vaccine reduced the risk of hospitalization by up to 94%.
The preliminary study, which has not yet been peer reviewed, is the first to look at the two vaccines’ effect on preventing severe illness resulting in hospitalization across an entire country, with previous efficacy results coming from clinical trials.
The EAVE II project, carried out by researchers from the Universities of Edinburgh, Strathclyde, Aberdeen, Glasgow and St Andrew’s and Public Health Scotland (PHS), analyzed a dataset covering almost the entire Scottish population of 5.4 million.
Researchers analyzed data for every week between December 8 and February 15. During this period 1.14 million vaccines were administered (some 650,000 people got the Pfizer shot and some 490,000 had Oxford-AstraZeneca) with 21% of the Scottish population receiving a first dose, according to a University of Edinburgh press release.
Among those aged 80 years and over -- one of the highest risk groups -- vaccination was associated with an 81% reduction in hospitalization risk from Covid-19 in the fourth week, when the results for both vaccines were combined, according to the press release.
“These results are very encouraging and have given us great reasons to be optimistic for the future. We now have national evidence -- across an entire country -- that vaccination provides protection against Covid-19 hospitalizations,” lead researcher Aziz Sheikh, director of the University of Edinburgh’s Usher Institute, said in the release.
Roll-out of the first vaccine dose now needs to be accelerated globally to help overcome this terrible disease.”
The researchers say the findings are applicable to other countries that are using the Pfizer and Oxford-AstraZeneca vaccines but caution that the data does not allow for comparisons between the two vaccines. “We haven't done a direct comparison between the two,” Sheikh said during a Monday news press conference.
Dr. Jim McMenamin, national Covid-19 incident director for PHS, stressed that the results are from a single dose, rather than a complete course of the vaccine. He said the bottom line is the team are “very encouraged” by the national data that shows the Pfizer and Oxford-AstraZeneca vaccines “are providing substantial protection against the risk of hospital admissions.
“No matter which of the two vaccines that any of our population are receiving, on the basis of the information that we're presenting ... there's encouragement, about the effect of both vaccines,” he added.