The data, released by the University of Edinburgh, was gathered using a Scotland-wide Covid surveillance tool.
Figures show the Pfizer-BioNTech vaccine is 90 per cent effective and the Oxford-AstraZeneca jab 91 per cent effective in preventing deaths in people who have been double vaccinated but who have tested positive for coronavirus in the community.
The study is the first to show across an entire country how effective vaccines are at preventing death from the Delta variant, which is the most dominant form of Covid-19 in the UK.
Researchers defined death from Covid-19 as anyone who died within 28 days of a positive PCR test, or with Covid-19 recorded as a cause of death on their death certificate.
The study analysed data from 5.4 million people in Scotland between April 1 and September 27 this year.
During this period, 115,000 people tested positive for Covid-19 using a PCR test in the community, rather than in hospital, and there were 201 Covid-related deaths recorded.
No deaths have been recorded in those who have been double vaccinated with the Moderna vaccine in Scotland, according to the data.
Researchers said it is therefore not possible to estimate this particular vaccine’s effectiveness in preventing Covid-related deaths.
The research team from the University of Edinburgh, University of Strathclyde and Public Health Scotland analysed the dataset as part of the “EAVE II project” – Early Pandemic Evaluation and Enhanced Surveillance of Covid-19 – which uses anonymised linked patient data to track the pandemic and the vaccine rollout in real time.
Professor Aziz Sheikh, director of the University of Edinburgh’s Usher Institute and EAVE II study lead, said: “With the Delta variant now the dominant strain in many places worldwide and posing a higher risk of hospitalisation than previous variants seen in the UK, it is reassuring to see that vaccination offers such high protection from death very shortly after the second dose.
“If you still have not taken up your offer to be vaccinated, I would encourage you to do so based on the clear benefits it offers.”
Professor Chris Robertson, of the University of Strathclyde and Public Health Scotland, said: “This study shows the value of carrying out analyses of routine healthcare data available in near real-time.
“Our findings are encouraging in showing that the vaccine remains an effective measure in protecting both ourselves and others from death from the most dominant variant of Covid-19. It is very important to validate these early results in other settings and with a longer follow-up study.”
To increase confidence in these early findings, researchers said data gathering needs to be repeated in other countries and settings, and with longer follow-up time after full vaccination.
The team behind the study said due to the observational nature of the figures, data about vaccine effectiveness should be interpreted with caution and it is not possible to make a direct comparison between both vaccines.